Multi-objective Optimisation of Bamboo Tensegrity Structure for Post-disaster Immediate Relief

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It addresses concerns such as time-consuming tent delivery as the first response during emergencies and cost-effectiveness and exploits the self-erecting affordances of tensegrity structures. The research adopts a multi-phase methodology, an iterative multicriteria simulation and prototyping optimisation. The three stages are: (1) computational simulation followed by multi-objective optimisation, (2) full-scale prototyping, and (3) a second round of multi-objective optimisation informed by prototype evaluations. The discussions around the self-build bamboo tensegrity sleeping structures are focused only on the compression and tensional elements (without skin or façade, which will be the focus of a subsequent study). Five design parameters are investigated: the number of bamboo struts, overall height, degree of rotation, and radius of the top and bottom sections. By optimising these parameters, three performance criteria are considered to evaluate spatial needs and portability: the possible number of occupants, the total weight, and the length of each bamboo strut. The study finds that after optimisation, these shelters are best suited to occupancy rates of one to five people, however, three people are required to erect the structures and carry longer bamboo culms so this must be factored into any potential deployment scenario. Bamboo Structures Tensegrity Disaster Relief Shelters Computational Simulation and Multi-objective Optimisation Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 INTRODUCTION The number of natural disasters around the world is increasing, with in excess of 268 million people affected in the first decade of the millennium by 394 events, as reported in 2011 (Guha-Sapir et al., 2012 ). Globally, in the year of 2019, 398 natural disasters were recorded, with the Asia region suffering the most (40%), with floods and storms being the two deadliest types of disaster (CRED, 2020 ). In the year of 2023, 399 disasters related to natural hazards were recorded by the Emergency Events Database (EM-DAT), with the earthquakes in Turkey and Syrian Arab Republic in February 2023 as the most catastrophic event in 2023 based on mortality and economic damage (CRED, 2024 ). There is thus a growing need for emergency accommodation to provide shelter for those temporarily displaced by these events. In light of the current global situation in terms of both economic and climate-related factors, it is necessary that this provision be sustainable in both regards. While there are numerous existing solutions to this issue- emergency shelters are usually simply tents such as would be used for camping, and temporary shelters can be structures such as shipping containers, these historic solutions bring their unique problems. For instance, the logistical arrangements of transporting and situating shipping containers can be difficult in disaster-stricken areas and care must be taken to ensure their suitability, for example with regard to contaminants (Fariña et al., 2024 ). The economic and environmental costs associated with shipping bulky, heavy structural materials to affected areas can be exorbitant and this budget could be better spent on other aspects of disaster management such as establishing temporary infrastructure for food supply and medical care. While tents are a cheap and simple solution, their use-case scenarios are limited in terms of climate, temperature, substrate, local hazards, etc. The significance of the solution which is aimed to be developed during this research endeavour is that the bamboo tensegrity design is flexible and scalable to cater to spatial needs and therefore applicable to a wider range of contexts than the aforementioned solutions. The proposed shelter could potentially transcend the categorization which details only the emergency use classification, with the objective being that the rapid assembly process has become familiar prior to emergency use. The use of tensegrity structure is designed to minimize the number of elements in compression, thus simplifying both the design and the building process. The elements in tension in a tensegrity structure are straight, which simplifies the building process as there is no requirement for bending or forming joints. The structure can also be adaptable, depending on the number of compression elements and scalable depending on requirements or available materials. The application is also suggested in places where bamboo is abundant, hence structural elements are locally sourced, and it is easily transportable since only the tensile elements and skin might be imported to site. However, it should be noted that in areas where bamboo is not abundant, other materials can be substituted for the compression elements provided they are sufficiently lightweight and their compression strength equals or exceeds that of bamboo. In brief, this research aims to optimise a system of flexible shelter design for one to six people utilizing tensegrity structures which is quick to deploy, easily assembled by unskilled workers, and utilizes locally sourced, sustainable materials for the structural members, for instance, bamboo in the Asia Pacific region, an area historically hard-hit by extreme weather events such as typhoons and tsunamis. The research question is, “What are the trade-offs in terms of structural and spatial arrangements to achieve an optimum habitable space?” LITERATURE REVIEW The previous section has outlined the severity of the situation regarding to the global disasters and this relevant literature section elaborates on four main ideas, with an aim to position this research: the post-disaster relief shelters, tensegrity structure, bamboo tensegrity structure, and multi-objective optimisation. Post-disaster relief shelters According to the United Nations Human Rights Council (UNHRC, henceforth), there are three stages to consider in the post-disaster scenario: the immediate relief period, the rehabilitation period and the reconstruction period (UNHRC, 2016 ). This tensegrity study looks at anticipation for the immediate relief period, the temporary shelters as first response. In the guidelines, ‘Shelter After Disaster’ published by the Office for the Coordination of Humanitarian Affair of United Nations (IFRC, 2015 ), it is stated that there are disadvantages to tents which are usually distributed immediately following a disaster. The drawbacks include issues such as sanitation and amenities supply but also focuses on aspects such as lack of security and privacy. In the more recent UNHRC report (UNHRC, 2019 ), shelter design criteria encompasses: hazard risks and safety, timeliness and construction speed, lifespan, size and shape, privacy, security and cultural appropriateness, ventilation and thermal comfort, environmental considerations, cost effectiveness and standards and building codes. In addition, a local construction and the possibility for modification to suit individual needs are highlighted. Tensegrity structure is proposed to be able to meet some of the above-mentioned design criteria, particularly in terms of timeliness and construction speed. Tensegrity structure Tensegrity is a portmanteau word and stands for “tensional integrity”. The definition of tensegrity according to Pugh ( 1976 ), is that “a tensegrity system is established when a set of discontinuous compressive components interacts with a set of continuous tensile components to define a stable volume in space”. Three pioneers are often mentioned in relation to tensegrity, namely Buckminster Fuller, David Emmerich and lastly Kenneth Snelson who experimented with this system in the 1960s. Micheletti and Podio-Guidugli ( 2022 ) provide a comprehensive 70 year review of tensegrities including more recent applications such as with a parametric approach to vaulted tensegrity networks (Liapi and Kim, 2004 ) and double layer tensegrity grid (Gomez-Jauregui et al., 2018 ). Anzalone et al. ( 2017 ) proposed tensegrity as a solution to a rapidly deployable structure. They state the advantages of tensegrity structures as being self-erecting, efficient in terms of the number of members in compression, resilient, allowing for system flexibility and using standard linear (straight) elements. They also propose a system of computational design -RDAT- to simplify the design process. Abdelmohsen et al. ( 2016 ) also used computational design in their research into tensegrity façade design, and found that they could also generate curved skin surfaces using this method. On a related note, Sterk suggested than tensegrity can be used in responsive architecture to adapt to various weather conditions (Sterk, 2003 ). He posits moreover that depending on the actuators in the structure- the intersections of the tensile and compressional members- the structure can be designed to be resistant to earthquakes, high winds and other weather conditions. Song et al. ( 2022 ) moreover propose a system of tessellated tensegrity structures which could be used to facilitate modular construction, further enhancing the adaptability of the system. While the historical perspective of tensegrity is not the focus of this paper, practical applications beyond conceptual design in the built environment are quite limited. To avoid confusion, in this study; the compressive elements made of full culm bamboo are called bamboo struts and the tensional elements are called cables. The design which the researchers adopted for the immediate relief shelter is the T-Prism, which is the simplest tensegrity structure. The coordinate system used is the cylindrical coordinate system, with reference to Burkhardt ( 2008 ) as seen in Fig. 1 . In the unrotated (or untwisted) triangular prism, the height of the structure is equal to the length of the struts. This structure has no stability as the struts are constrained only in one direction (the tensional elements linking them at top and bottom). Rotating the structure allows for additional tensional elements to be placed between the top of the struts and the base of the adjacent struts. The geometry of the triangles thus formed dictates the resultant height of the structure and the extra constraint afforded by these extra elements in tension allows the structure to be freestanding. In terms of the design parameters, the geometry of the triangles is variable by rotating the prism to a greater or lesser degree, with commensurate changes in the lengths of the longer elements in tension (between the tops and bases of the adjacent struts). Bamboo tensegrity structure Regarding bamboo construction using tensegrity, Aditra and Widyowijatnoko ( 2016 ) proposed a computational design system for a geodesic dome using a lattice structure, suggesting that bamboo is a suitable material for this application. They also devised a system of laser cutting joints which could be ported to those used in tensegrity structures. In a subsequent study, Widyowijatnoko and Harries ( 2020 ) also researched bamboo as a building material and examined various methods of forming joints. They found that bamboo has excellent tensile strength and stiffness, having an ultimate tensile strength of between 31 and 85 N/mm 2 and while there is considerable variation due to the non-standard nature of the material, this is almost certainly adequate for the compression loads in a tensegrity structure which are lower than in a structure built purely in compression. Their exhaustive work on joints however is arguably of greater interest, because through a combination of vernacular construction techniques and engineered joints, they have discovered ways to mitigate the stresses in the modes where bamboo is weakest. The use of bamboo for compression members in this paper is to challenge documented obstacles to practical application of tensegrity technology (Burkhardt, 2008 ). The obstacles include strut congestion, poor load response, fabrication complexity and inadequate design and analysis tools. Multi-objective Optimisation In comparison with a single-objective optimisation which produces a single solution; multi-objective optimisation deals with multiple conflicting objectives which need to be optimised concurrently. Moroni et al. ( 2024 ) state that due to the conflict which can arise from having two or more objectives, multi-objective optimisation can rely on preference-based methods or Pareto optimisation for resolution. The former assumes bias or preference on the part of the designer while the Pareto approach described below accepts that no single solution can improve one aspect of a problem or situation without causing deterioration in another. One of the earliest contributions to knowledge came from Vilfredo Pareto, a French Italian economist who introduced the concept of Pareto efficiency in the late 19th century, as documented in the updated translation of the manual (Pareto, 2014 ). His 80 − 20 rule states that up to a certain point, 80% of results can be achieved with 20% of effort, suggesting that anything in excess of a nominally 80% “perfect” solution will require exponentially increased effort. The main idea of Pareto was that in the face of conflicting goals and limited resources, the optimal solution can be defined as being imperfect- a compromise between these conflicting goals, or rather a set of compromises. Thus, one goal cannot be achieved without degrading another outcome, as mentioned previously, and the optimal outcome is, of necessity, a trade-off. The Pareto principles were adopted to computational optimisation methods with evolutionary algorithms, in particular in terms of negotiation of conflicting goals. Evolutionary multi-objective optimisations, according to Deb ( 2011 ), take solutions based on several different criteria which are then used to populate datasets for the next iteration of solutions. This population-based approach is what differentiates evolutionary multi-objective optimisations from evolutionary single-objective optimisations. A typical approach uses a generation engine, often using parametric design, which feeds into an evaluation engine. Both of these engines feed their results into an exploration engine, which uses evolutionary algorithms. In a comprehensive literature review by Moroni et al. ( 2024 ), it was mentioned that multi-objective optimisation is used in different fields related to built environment. In architecture, it is applied to problems in environmental comfort, layout distribution or shape. For sustainability issues, there is tension in the goals between environmental and economic considerations, and although not explicitly mentioned in the Moroni article, arguably social sustainability is also a potentially conflicting goal within the overarching objective of sustainability. Of relevance to this current research is the application of multi-objective optimisation to the following variables identified by Moroni et al, all of which have the potential to generate tension in the manner described by Pareto. In terms of structure, there are: structural design, structural performance (including deformation and displacement), and geometry or topology. Under architecture, the considerations are broadly similar for the purposes of the proposed emergency shelters. Under materials, there are: building’s elements, its characteristics, and its quantities. Moreover, there are more specific variables which include: building height, geometry of floorplan, interior space vs. external volume, envelope shape and materials, number of structural elements, design appearance, and cost. It is probable that the Pareto principle applies here since many of these considerations cannot be optimised without detriment to other goals. Interestingly, in the Moroni study, only 42 out of the 203 reviewed articles stated that combination of objectives from different categories was not a goal of the multi-objective optimisation process, which possibly suggests that the Pareto principle was followed in the majority of cases (Moroni et al., 2024 ). RESEARCH METHODOLOGY This research adopts a multi-phase methodology based on ‘Iterative Multicriteria Simulation and Prototyping Optimisation’ (Niño-Pérez et al., 2017 ). This approach integrates computational simulation, multi-objective optimisation, and full-scale prototyping in iterative cycles to systematically evaluate and refine the design process. The research is structured into three main stages: (1) computational simulation followed by multi-objective optimisation, (2) full-scale prototyping, and (3) a second round of multi-objective optimisation informed by prototype evaluations. In the first stage, computational simulations were conducted to assess the performance of five design parameters. A multi-objective optimisation process was then applied to identify the characteristic of the most effective solutions based on predefined objectives, including amount of habitable space provided (measured by number of occupants), overall weight and each bamboo strut’s length. The second stage involved the construction and evaluation of two full-scale prototypes to assess the feasibility and practicality of the optimised design under different material configurations. Both prototypes maintained identical dimensions but varied in terms of joints and cable materials: one utilized steel cables for greater tensile strength, while the other employed braided nylon cord for its wider availability of non-specialist joints. This comparison provided critical insights into how different material choices impact the predefined objectives. In the third stage, reflections and evaluations from the prototyping stage provided critical insights into the structure’s functionality, assembly efficiency, and overall performance. Based on these findings, a second round of multi-objective optimisation was revised and conducted, incorporating feedback to refine the design further, enhancing its efficiency. Design Parameters The selected tensegrity structure for the immediate relief shelter is the T-Prism, and its design of the T-Prism tensegrity is defined by five key design parameters: (1) the number of bamboo struts, (2) the overall height of the structure, (3) the degree of rotation of the bamboo struts, (4) the radius of the top section, and (5) the radius of the bottom section. The specific range and increments assigned to each parameter are detailed in Table 1 , providing a framework for systematic exploration and optimisation of the design. In this study, the number of bamboo struts is limited to a maximum of six, considering the assembly process. This constraint ensures that each strut can be held in place by a single person until the structure reaches equilibrium, facilitating a more practical and manageable construction process. The radius of the top and bottom areas are critical design parameters that directly impact the habitable area. As illustrated in Fig. 1 above, when the top and base areas (A’-B’-C’ and A-B-C) are identical, the efficiency of the usable space is reduced. In contrast, a structure with a more tapered, ‘pointed’ top optimises the internal space, improving both spatial efficiency and structural balance (and potentially wind resistance, though this was impossible to assess in this study due to the lack of skin or façade). Figure 2 illustrates the design parameters (x 1 -x 5 ). Table 1 Design parameters Design Parameters Lower Limit Increments Upper Limit x 1 : The number of bamboo struts 3 1 6 x 2 : The overall height (m) 3.0 0.1 6.0 x 3 : The degree of rotation 5 1 90 x 4 : The radius of the top section (m) 0.2 0.1 2.0 x 5 : The radius of the bottom section (m) 2.0 0.1 4.0 Design Performance This study focuses on two key aspects: spatial needs and portability. Regarding spatial needs, the immediate relief shelters are designed primarily for sleeping, similar to camping tents. The research evaluates the habitable area (Y1) based on the number of occupants, which is set at a maximum of six individuals—the typical size of a family. This assessment ensures that the shelter provides adequate space for basic rest and protection while maintaining a compact and efficient footprint suitable for emergency use. To determine the spatial requirements for individual occupants, this study uses a standard camping mat size of 65 cm × 183 cm (Fig. 3 ) as a reference for a single sleeping space. The overall head clearance for one person is 1.25 m in height, ensuring sufficient comfort while lying down. Regarding portability, this research evaluates two key criteria: the overall weight (Y2) and length (Y3) of each bamboo struts. The overall weight is calculated based on an 8 cm diameter full-culm Gigantochloa apus , a species commonly used in construction and native to Southeast Asia. It has a high strength-to-weight ratio, making it well-suited for portable structures. The length of the bamboo struts directly impacts the portability of the structure. Shorter components are easier to handle, pack, and transport, particularly in emergency scenarios where rapid deployment is crucial. Although the weight of the hardware- cables, tensioners, etc.- is not unsubstantial, it was regarded as of only incidental importance to these calculations and has thus not been included. Computational Modelling and Simulation The modelling and simulation were conducted using Grasshopper™/Rhinoceros 3D™, where custom scripts were developed to generate and analyse the tensegrity structure. The geometrical modelling process, as illustrated in Fig. 4 , was scripted in Grasshopper to ensure flexibility in exploring various configurations. Once the geometrical modelling’s script was established, performance simulations were conducted, as shown in Fig. 5 , to evaluate the predefined objectives. The computational approach is used to allow rapid iteration and optimisation, the following stage. Multi-objective Optimisation The multi-objective optimisation in this study is designed to achieve an optimal balance between three key criteria: maximising the number of occupants while minimising both the total weight and length of the bamboo components, as shown in Eq. 1 below. This analysis is performed using Octopus, a multi-objective optimisation plugin for Grasshopper™ (Vierlinger, 2013 ), which leverages evolutionary algorithms to explore and refine potential design solutions. Equation 1 \(\:Minimize\:F\) = (- \(\:f\) 1 ( \(\:x\) 1 , \(\:x\) 2 , \(\:x\) 3 ) , \(\:f\) 2 ( \(\:x\) 1 , \(\:x\) 2 , \(\:x\) 3 ) , \(\:f\) 3 ( \(\:x\) 1 , \(\:x\) 2 , \(\:x\) 3 )) where F represents the set of solutions, \(\:f\) 1 corresponds to the objective of maximizing the habitable area, which is multiplied by -1 to transform it into a minimization problem, \(\:f\) 2 represents the objective of minimizing the total weight of the bamboo components, and \(\:f\) 3 denotes the objective of minimizing the length of the bamboo components. While \(\:x\) denotes the design parameters, defining the possible configurations of the structure (see Table 1 ). The optimisation process generates a wide range of possible configurations, evaluating each based on the defined objectives. The results are then visualized in a three-axis graph, where solutions are mapped to identify the Pareto front—a set of non-dominated solutions representing the best trade-offs among competing objectives (Ehrgott, 2005 ). RESULTS This section provides a descriptive account of investigations conducted through the three-stage iterative multicriteria simulation and prototyping. This section specifically examines how changes in five design parameters (x 1 -x 5 ) are considered, evaluated and implemented which as a result, influences the three design performance criteria (Y1, Y2, and Y3). Stage 1: Multi-objective Evolutionary Optimisation 1 The optimisation was conducted using Octopus, employing the NSGA-II algorithm with HypE-based reduction and mutation. The results, shown in Fig. 7 , consist of 20 optimised cases generated in the 100th generation. The three axes refer to the three previously mentioned evaluation criteria: habitable areas (Y1- green axis), total weight (Y2- blue axis) and strut’s length (Y3- red axis). Table 2 Optimised cases of the first optimisation Optimum Cases Design Parameters Performances x 1 x 2 x 3 x 4 x 5 Y1 Y2 Y3 No of bamboo struts Overall height (m) Degree of rotation Radius of the top section (m) Radius of the bottom section (m) Habitable area (no of person) Overall weight of bamboo (kg) Length of each bamboo strut (m) 1.1 6 3.0 5 1.8 2.8 6 26.98 3.98 1.2 6 3.0 5 2.0 2.2 5 25.49 3.76 1.3 6 3.0 5 1.8 2.0 4 24.64 3.63 1.4 6 3.0 5 1.6 2.0 3 24.32 3.59 1.5 6 3.0 5 0.8 2.0 2 23.78 3.51 1.6 5 3.0 5 1.8 3.0 6 24.51 4.34 1.7 5 3.0 5 1.6 2.8 5 23.57 4.17 1.8 5 3.0 5 0.9 2.8 4 22.97 4.06 1.9 5 3.0 5 0.4 2.0 2 20.22 3.58 1.10 4 3.0 5 1.1 3.6 6 22.09 4.89 1.11 4 3.0 5 1.0 3.2 5 20.62 4.56 1.12 4 3.0 13 1.2 2.7 4 19.89 4.38 1.13 4 3.0 5 1.0 2.7 3 19.06 4.21 1.14 4 3.0 5 0.3 2.0 2 16.42 3.63 1.15 4 3.0 5 0.2 2.0 1 16.37 3.62 1.16 3 3.0 89 1.1 3.9 5 19.46 5.74 1.17 3 3.0 89 1.1 3.8 4 19.17 5.65 1.18 3 3.0 38 1.0 3.1 2 17.08 5.04 1.19 3 3.0 9 1.0 2.6 2 15.18 4.48 1.20 3 3.0 36 0.8 2.1 1 14.03 4.14 In Fig. 8a, the shortest strut-optimised case, Solution 1.5 fulfil the Y3 criteria the most, which is optimised for the shortest strut length. This solution features six of 3.5 m struts, weighs approximately 24 kg, and accommodates two people. Meanwhile, in Fig. 8b, the lightest optimised case, Solution 1.20 fulfil the Y2 criteria the most. This lightest optimised design was selected for further analysis in Stage 2. Weighing 14 kg, it consists of three of 4.1 m bamboo struts, has an overall height of 3 m, and is designed for one person sleeping. Table 3 and Fig. 9 show solutions of each occupancy rate with fewest number of bamboo struts for the first optimisation. Table 3 The optimised cases based on number of occupants (first optimisation) Optimum Cases Design Parameters Performances x 1 x 2 x 3 x 4 x 5 Y1 Y2 Y3 No of bamboo struts Overall height (m) Degree of rotation Radius of the top section (m) Radius of the bottom section (m) Habitable area (no of person) Overall weight of bamboo (kg) Length of each bamboo strut (m) 1.20 (selected) 3 3.0 36 0.8 2.1 1 14.03 4.14 1.19 3 3.0 9 1.0 2.6 2 15.18 4.48 1.13 4 3.0 5 1.0 2.7 3 19.06 4.21 1.17 3 3.0 89 1.1 3.8 4 19.17 5.65 1.16 3 3.0 89 1.1 3.9 5 19.46 5.74 1.10 4 3.0 5 1.1 3.6 6 22.09 4.89 Stage 2: Prototyping In the second stage, Solution 1.20 from the initial optimisation was measured to assess its assembly and disassembly ease, design parameters, and performance. Two 1:1 scale physical prototypes were assembled. The two prototypes shared the same dimensions and mainly differed in the types of joints and cabling (Fig. 10). Based on the bamboo and cable length data from Grasshopper, the materials were prepared. Bamboo lengths were extended by 10 cm on each end to prevent cracking around bolt holes, while cable lengths were extended by 20 cm on each end. Each prototype was pitched at least twice with tensional elements (cables or rope) already attached to bamboo struts. They were pre-assembled on the ground and moved to the target location. The three bamboo struts (4.1 m long) took two people to carry, and once pitched the tectonic (only bamboo struts and cables, without skin) system can be moved by one person. This illustrates the mobility of the tectonic elements. The first prototype used steel cables attached to an eyelet bolt passed through the 8cm in diameter Apus bamboo struts with an eyelet nut on the other end via steel cable tensioners as noted above, refer to Fig. 11. During the second pitch exercise, the authors noted that most of the 24 joints can be fixed joints particularly the top triangle and the bottom triangle shaped cables, with the exception of the three diagonal cables. This will decrease the post-tensioning duration. In total the first prototype was assembled and disassembled three times, and the total time to pitch decreased from eight to seven minutes on the last assembly as the researchers became familiar with the assembly steps. On an incidental note, the assembly sequence can perhaps be standardised for future builds for ease of assembly. The second prototype (Fig. 12) utilised simple screwgate karabiners or D shackles, attached to the same diameter (8cm) Apus bamboo via doubled cord lashing. Braided nylon cord was used because it is widely available worldwide and requires no special tools to work with. This is particularly germane because specialist equipment and hardware is not readily and economically available everywhere in the world, especially in emergency situations. The doubled cord was pre-stretched to achieve its non-stretchy state (also to maintain the accuracy of measurement), and surprisingly, the stretching rate was 46%. This results in 8mm diameter cord reducing to 5mm. Post-tensioning needed to be carried out in mini steps, ensuring the three struts were adjusted at the same time or in sequence. The difference between prototypes 1 and 2 in this regard is that due to the elastic nature of the braided nylon cord, the post-tensioning process took more time. From the two prototypes, it can be observed that, in terms of habitable area, computational modelling suggested that the prototype could accommodate one person. However, during prototyping, it was observed that it could accommodate two people (Fig. 13 ). Assembling the tensegrity structure to a self-standing state took approximately eight minutes, with an additional five minutes required to tension the cables. Disassembly took less than one minute for both prototypes. The number of people required for assembly and disassembly matched the number of struts—three in this case. For easy reference, a comparative summary is provided in Table 4 . Table 4 Comparative summary of Prototype 1 and Prototype 2 Prototype 1: Prototype 2: ▪ The use of more specific hardware such as steel cables and tensioners ▪ Quick post-tensioning process ▪ Pre-stretching tensional elements- the cables- is not necessary ▪ Measurements can be maintained as blueprints ▪ Stiffness of structure is ensured ▪ Widely available/ easy to find hardware ▪ Post-tensioning process can be as long as pitching (seven to eight minutes) ▪ Rope needs to be pre-stretched ▪ Accuracy of the measurements is difficult to maintain due to the stretchy character of the rope ▪ Structure is easy to flex Stage 3: Multi-objective Evolutionary Optimisation 2 The third stage aimed to rectify the design parameters based on results from Multi-Objective Optimisation stage 1 and insights from Prototypes 1 and 2. Adjustments were made as follows; the summary is presented in Table 5 : 1. Number of bamboo struts: Optimised cases (Table 3 ) initially had 3 to 4 struts. Then, the range was adjusted from 3–6 struts to 3–4 struts. 2. The overall height: Since all optimised cases (Table 3 ) had a height of 3 m (the minimum lower limit), the total height range was lowered to 2.0–3.0 m. 3. The degree of rotation: Optimised cases indicated possible strut-cable intersections due to a small rotation degree. To address this, a new script was added to incorporate clash detection, eliminating cases where intersections were detected. 4. Top section radius: The optimised cases (Table 3 ) showed a top radius range of 0.8–1.1 m. The maximum was set at 1.1 m, with an adjusted range of 0.2–1.1 m. 5. Bottom section radius: The optimised cases had a bottom radius of 2.1–3.9 m. Observations from the prototypes (Fig. 13 ) showed that, despite being designed for one person, the structures provided ample space for two people. Thus, the minimum bottom radius was reduced from 2.0 m to 1.0 m, corresponding to the length of a standard sleeping mat. Additionally, the sitting height was lowered from 1.25 m to 0.9 m. The initial 1.25 m estimate was based on tent dimensions with sloped sides, so maximum head height is available only in the centre of the tent, whereas observations indicated a lower height would be sufficient. The sleeping area remained unchanged, referencing a standard sleeping mat size of 65 cm × 183 cm. The second stage of optimisation yielded 11 optimised cases, as shown in Fig. 14 . However, none of these cases could accommodate six people. Table 5 Refined design parameters Design Parameters Lower Limit Increments Upper Limit x 1 : The number of bamboo struts 3 1 4 x 2 : The overall height (m) 2.0 0.1 3.0 x 3 : The degree of rotation 5 1 115 x 4 : The radius of the top section (m) 0.2 0.1 1.1 x 5 : The radius of the bottom section (m) 1.0 0.1 4.0 Table 6 Optimised cases of the second optimisation Optimum Cases Design Parameters Performances x 1 x 2 x 3 x 4 x 5 Y1 Y2 Y3 No of bamboo struts Overall height (m) Degree of rotation Radius of the top section (m) Radius of the bottom section (m) Habitable area (no of person) Overall weight of bamboo (kg) Length of each bamboo strut (m) 2.1 4 2.1 6 1.0 3.6 5 19.78 4.37 2.2 4 2.1 6 1.0 3.2 5 18.27 4.04 2.3 4 2.1 6 1.1 2.9 4 17.33 3.83 2.4 4 2.1 7 0.6 2.8 3 16.32 3.61 2.5 4 2.1 13 0.3 2.0 2 13.39 2.96 2.6 4 2.0 7 0.5 1.8 1 12.55 2.78 2.7 3 2.3 74 1.0 3.8 5 17.98 5.30 2.8 3 2.4 41 1.0 3.5 4 17.17 5.06 2.9 3 2.2 89 1.0 3.3 3 16.09 4.74 2.10 3 2.1 92 1.0 2.3 2 12.96 3.82 2.11 3 2.0 9 1.0 2.3 1 12.31 3.63 Similarly with Stage 1, several solutions are presented below illustrating the most optimal solutions based on each performance criterion. In Fig. 15a, the shortest strut-optimised case, Solution 2.6 fulfils the Y3 criteria the most, which is optimised for the shortest strut length. This solution features six of 2.78 m struts, weighs approximately 12.55 kg, and accommodates one person. Meanwhile, in Fig. 15b, the lightest optimised case, Solution 2.11 fulfils the Y2 criteria the most. Weighing 12.31 kg, this solution consists of three of 3.6 m bamboo struts, has a height of 2.0 m, and is designed for one person sleeping. In terms of habitable area, the optimised cases were analysed based on occupant capacity (Y1), shown in Table 7 and Fig. 16. The data was grouped by the number of occupants, selecting the case with the fewest bamboo struts. Table 7 The optimised cases based on number of occupants (second optimisation) Optimum Cases Design Parameters Performances x 1 x 2 x 3 x 4 x 5 Y1 Y2 Y3 No of bamboo struts Overall height (m) Degree of rotation Radius of the top section (m) Radius of the bottom section (m) Habitable area (no of person) Overall weight of bamboo (kg) Length of each bamboo strut (m) 2.11 3 2.0 9 1.0 2.3 1 12.31 3.63 2.10 3 2.1 92 1.0 2.3 2 12.96 3.82 2.9 3 2.2 89 1.0 3.3 3 16.09 4.74 2.8 3 2.4 41 1.0 3.5 4 17.17 5.06 2.7 3 2.3 74 1.0 3.8 5 17.98 5.30 DISCUSSION While the Results section considers how changes in five design parameters (x 1 -x 5 ) are evaluated and implemented, this section examines how improvements in performance are achieved as a result of the iterative simulation and optimisation. To summarise the changes, Table 7 provides a comparative design parameters data as recorded in first optimisation and second optimisation. It shows that the evolution of the system design is optimised further by changing the upper limits of x 1 -x 4 (marked in blue fonts) variables and the lower limit of x 2 (marked in orange fonts) variables. The rest of the discussion related to improvements will be expanded based on the three performance criteria, followed by reflections on the suitability of bamboo for compression members in tensegrity structure. In general, the second optimisation produces fewer optimum solutions (11 solutions) in comparison with the first optimisation (which yielded 20 solutions). Second optimisation also eliminated the need for five-strut and six-strut structures and suggested three-strut and four-strut arrangements only. Table 7 Comparison of design parameters, first and second optimisation First optimisation Second optimisation Design Parameters Lower Limit (Stage 1) Upper Limit (Stage 1) Lower Limit (Stage 3) Upper Limit (Stage 3) x 1 : The number of bamboo struts 3 6 3 4 x 2 : The overall height (m) 3.0 6.0 2.0 3.0 x 3 : The degree of rotation 5 90 5 115 x 4 : The radius of the top section (m) 0.2 2.0 0.2 1.1 x 5 : The radius of the bottom section (m) 2.0 4.0 1.0 4.0 Three design performance criteria The two key aspects are the spatial needs and portability, which is translated into objectives in the simulations and optimisations into evaluation of habitable area based on the number of occupants (Y1), the overall weight of the main structure (Y2) and length of each bamboo strut (Y3). Firstly, in terms of the habitable area (Y1 performance criteria) which is measured by the number of occupants, one of the main results derived from the second optimisation is that optimum cases do not fulfil occupancy rate of six persons. This might be due to the fact that with the decrease in height and the slope of the sides, the floor area is reduced in terms of acceptable head height (already reduced from 1.25m to 0.9m). From the first optimisation it is found that to achieve higher numbers of occupants does not always require higher number of bamboo struts. For example for five occupants, Solution 1.16 (first optimisation, refer to Table 2 ) requires three struts, weighs 19.46kg with a compromise of 5.74m long struts. The counterpart in the second optimisation of three struts and sleeps five, Solution 2.7 (Table 6 ), has an overall weight of 17.98 kg with 5.30m long struts. Both solutions have a trade-off regarding extremely long bamboo struts which might reduce the ease of transporting in a normal truck. The second optimisation, however, shows that a three-strut arrangement can fulfil a wide range of occupancy levels, from one to five occupants which requires bamboo poles between 3.63m to 5.30m. It is also worth noting that the second optimisation produces the most five-person shelter options with three solutions (Solution 2.1, 2.2 and 2.7). Figure 17 and Table 8 show comparison of three-strut optimum cases for five occupants, Solution 1.16 (from first optimisation) with Solution 2.7 (from second optimisation). As comparison, the corresponding solution in second optimisation provided more effective structure in terms of lower overall height, and also smaller radius on both top and bottom. This also results in lower overall weight and shorter struts. Table 8 Three-strut five-person shelter options: first and second optimisations Optimum Cases Design Parameters Performances x 1 x 2 x 3 x 4 x 5 Y1 Y2 Y3 No of bamboo struts Overall height (m) Degree of rotation Radius of the top section (m) Radius of the bottom section (m) Habitable area (no of person) Overall weight of bamboo (kg) Length of each bamboo strut (m) 1.16 3 3.0 89 1.1 3.9 5 19.46 5.74 2.7 3 2.3 74 1.0 3.8 5 17.98 5.30 Figure 18 shows the simulated possibility utilising sleeping mat (habitable space) dimensions as reference, using Solution 2.7. Storage space is also included in the simulation, shown as shaded area inside the structure with a height of 1m. It is also noted during the research that sleeping positions of six as posited in Fig. 2 that the higher number of occupants, the more internal circulation space is required. Although the provision for preliminary study is sufficient, further attention should be given to space arrangement mainly for shelters which are to accommodate three to five occupants. Secondly, in terms of overall weight of bamboo (Y2 performance criteria). In general, the range of total weight was reduced from the first to the second optimisation. The first optimisation sees a range of 14 kg (one person) to 25.50 kg (five person) to 26.98 kg (six person); whereas the second optimisation sees a range of 12.3 kg (one person) to 19.78 kg (for five person). Factors affecting the significant reduce of the total weight are the reduced upper limit of overall height (x 2 ) and the reduced upper limit of bamboo struts from six to four in second optimisation. It can be predicted that the higher number of occupants, the lower the weight per person is. However, from Table 9 , the four-person optimised solutions have the same ratio as the five person solutions, might suggest fact that the five-person shelters have most favourable ratio between weight and number of occupants. Table 9 Weight/person according to occupancy (second optimisation) Solution no Occupancy (person) Weight/person (kg) 2.1, 2.2 and 2.7 5 4 2.3 and 2.8 4 4 2.4 and 2.9 3 5 2.5 and 2.1 2 6–7 2.6 and 2.11 2 12–13 Based on the observations during Prototype 1 and 2 which show a tensegrity for one person derived from Solution 1.20’s dimensions, two people can lift three poles of option 1.5 (4.1m long struts), stacked together. The first optimisation, Stage 1, shows that the total weight of this structure is 14 kg. In comparison, a safe weight for one person handling is generally considered to be 25kg. The structure came under this safe weight, however, due to the length of each bamboo strut; it was as a result unstable to be carried by one person. It took two people to carry the struts with all cables attached, one at each end; and took three people (basically one person per strut) to hold the struts until the structure reached equilibrium which took seven minutes. Thus, a one-person shelter required two people to carry and three people to pitch. This shows that from the practicality aspect of assembling the tensegrity structure, it can be crucial to suggest the most optimum solution(s). Subsequently in Stage 3 (second optimisation), two solutions for one-person-shelter are Solution 2.6 which is four-strut and Solution 2.11 which is three-strut. Both solutions weigh approximately the same despite the difference number of struts, between 12.3kg to 12.6 kg which is lower from the first optimisation of 14 kg. The difference in assembly is that the four-strut solution requires more people (four at minimum) compared to the three-strut which requires three people to pitch following the one-strut-one-person-to-hold concept. Thirdly, related to each strut’s length (Y3 performance criteria), this can also suggest the amount of materials needed. Apart from the transport issue, for bamboo struts which are too long (more than 4.5m), the anticipated issues are difficulty to find the culms and the compromised stiffness of the tectonic system. Moreover, bamboo poles are not perfectly straight and usually tapered at one end. The longer the culm is, the possibility to have a slightly curved strut is higher. In the experience of the researchers, longer culms may also be prone to buckling under compression load. From the first optimisation, the shortest strut is 3.51m (Solution 1.5) and the longest strut is 5.74m (Solution 1.16). From the second optimisation the shortest strut is 2.78m (Solution 2.6) and the longest strut is 4.37m (Solution 2.1). The refined five design parameters, shown in Table 5 , illustrate that the second optimisation allows solutions to be within the range of acceptable length, less than 4.5m. The shortest strut suggested in the second optimisation is also in accordance with Stage 2 experience to not have the strut more than 2.8 m long for easy portability by one person. Bamboo for tensegrity structures The second part of this discussion looks at general observations of the use of bamboo for this type of unique structure. This shelter design addresses several design criteria according to UNHRC ( 2019 )’s report, particularly the environmental considerations, the use of local materials and cost effectiveness, with the use of full culm bamboo poles in places where bamboo is abundant, rather than waiting for imported tents to be shipped over high mileages to disaster zones. This study also supports what Anzalone et al. ( 2017 ) proposed, a tensegrity as a solution for a rapidly deployable structure. The effectiveness in terms of number of members in compression and allowing flexibility using straight elements (which is an inherent characteristics of full culm bamboo poles) is illustrated through this preliminary study. The lightweight structure is easy to transport and move even once it is in pitched condition (without skin or façade). This exploration also puts tensegrity as a practical and yet feasible solution for post-disaster immediate relief. In addition, the structure is considered to be self-build, thus allowing for further modification by the occupants. CONCLUSION This study illustrates the possible utilisation of full culm bamboo poles as compression members in tensegrity structures for the purpose of immediate relief shelters. This paper addresses key shelter design criteria (UNHRC, 2019 ) in terms of timeliness and construction speed, cost effectiveness and the use of local material use for places where bamboo is in abundant, the lack of availability of specialist hardware and tools (the alternative materials and hardware), easy transportability (by two people) and easy relocation once it is pitched by one person. This study also challenges the four primary obstacles of practical applications of tensegrity structures (Burkhardt, 2008 ), in particularly the challenge of inadequate design and analysis tools. The authors utilised a multi-phase methodology which includes combination of iterative multicriteria simulation and prototyping optimisation. The key findings from this research are that with increasing Pareto front optimisations, the occupancy rate decreases (none of the second round of optimised designs was capable of accommodating six people). There is also the consideration of using longer lengths of bamboo in terms of structural issues (being prone to buckling), transportation (since a truck might typically accommodate 4.5 metre lengths, and a sole person can realistically move lengths of up to 2.8 metres) and sourcing a sufficient number of straight culms. A further issue identified was that using polypropylene rope for the cable and tension system introduces a new set of complexities, since the rope tested in this research stretched by over 40%. While the focus of this study was on using bamboo, it should also be acknowledged that this solution is limited to certain geographical areas and while it may reasonably be assumed that other alternative materials with similar mechanical properties would perform similarly, this was not tested in this study. To reiterate the research question, it is “What are the trade-offs in terms of structural and spatial arrangements to achieve an optimum habitable space?”. Reference to Table 6 (second optimisation, in the results section) shows that when Y1 (habitable area) is high, Y2 and Y3 (overall weight and length, respectively) tend to be poor. However, there is more variance in Y3 than in Y2 which tends to have a relatively close linear relationship with Y1. The optimal compromise seems to be between Y1 = 4 and Y1 = 5. Thus, these shelters, based on requirements, are possibly best suited to these occupancy rates. For single or dual occupancy, options are limited because of the lengths of the culms required and the fact that two people are required to pitch these designs. For occupancy rates of six or more, the length of culms required becomes too great. Optimisation can be focused on shorter lengths of bamboo struts for easy transport by one or two people, while for the three to five-person shelters, the number of occupants need to be equal to or more than the number of bamboo struts for ease of disassembly. The trade-offs in terms of structural and spatial arrangements can be considered from two extremes. One side of the extreme is occupancy objective, and the other extreme is interrelated weight and length objectives. A good compromise facilitates a low number of struts for efficiency with a large bottom radius (footprint) but within an appropriate length to minimise buckling and ease transport (approximately 4.5m). To answer the research question, the trade-offs include unnecessarily large footprint which might not be suitable in every emergency situation and the ability to find the appropriate length of bamboo poles for the compression members. From the above-mentioned study and reflections, the future agenda focuses on the development of the thermally sound shelter skin made of a widely available sheeting, further improvements in the suitable hardware and tools (rope stretchability tests of different kinds of ropes, lashing techniques, fixed and non-fixed joints to ease the speed of assembly, etc), optimising the tensioning system and refining different solutions for the two main groups of shelters (one to two-person and three to six-person). Declarations Author Contribution First manuscript: the first author developed the Abstract, Introduction, Relevant literature, Rationale and Conceptual Design of Bamboo Tensegrity Structure sections; the second author ran the multi-objective optimisations; the first and second authors both built, dismantled and re-built the prototype; the first author wrote the Research Methodology section, the second author wrote the Results section; both first and second authors wrote Discussion section; and lastly the second author wrote the Conclusions section.Second manuscript (revision): the first and second authors co-edited the manuscript. References Abdelmohsen, S., Massoud, P. & Elshafei, A. (2016). Using tensegrity and folding to generate soft responsive architectural skins. Complexity & Simplicity. Presented at the 34th eCAADe Conference, Brussels: Education and Research in Computer Aided Architectural Design in Europe (eCAADe) , 2016. 529-536. Aditra, R. F. & Widyowijatnoko, A. (2016). Combination of mass customisation and conventional construction. 21st international conference of the association for computer-aided architectural design research in Asia CAADRIA , 2016. 777-786. Anzalone, P., Bayard, S. & Steenblik, R. (2017). Rapidly deployed and assembled tensegrity system. Acadia 2017 Disciplines & Disruption: Proceedings of the 37th Annual Conference of the Association for Computer Aided Design in Architecture , 2017. 92-101. Burkhardt, R. W. (2008). A practical guide to tensegrity design. Cambridge USA . CRED (2020). Natural disasters 2019: Now is the time to not give up. Brussels. CRED (2024). 2023 Disasters in Numbers: A Significant Year of Disaster Impact. Brussels. Deb, K. (2011). Multi-objective optimisation using evolutionary algorithms: an introduction. Multi-objective evolutionary optimisation for product design and manufacturing. Springer. Ehrgott, M. (2005). Multicriteria optimization , Springer Science & Business Media. Fariña, E. A., Panait, M., Lago-Cabo, J. M. & Fernández-González, R. (2024). Energy Analysis of Standardized Shipping Containers for Housing. Inventions, 9 , 106. Gomez-Jauregui, V., Quilligan, M., Manchado, C. & Otero, C. (2018). Design, Fabrication and Construction of a Deployable Double-Layer Tensegrity Grid. Structural Engineering International, 28 , 13-20. Guha-Sapir, D., Vos, F., Below, R. & Ponserre, S. (2012). Annual disaster statistical review 2011: the numbers and trends. CRED. Brussels. IFRC (2015). Shelter after disaster: Strategies for transitional settlement and reconstruction. In: Nations, U. (ed.). Liapi, K. A. & Kim, J. (2004). A parametric approach to the design of vaulted tensegrity networks. International Journal of Architectural Computing, 2 , 245-262. Micheletti, A. & Podio-Guidugli, P. (2022). Seventy years of tensegrities (and counting). Archive of Applied Mechanics, 92 , 2525-2548. Moroni, G., Forcael, E. & Berrios, C. (2024). Variables and objectives in multi-objective optimization for the integration of architecture, structure, and environmental impact: a literature review. Architectural Science Review , 1-17. Niño-Pérez, E., Rivera-Collazo, C. A., Cabrera-Ríos, M. & Méndez-Vázquez, Y. M. (2017). Iterative multicriteria simulation and prototyping optimization in manufacturing. 2017 Winter Simulation Conference (WSC) , 2017. IEEE, 481-492. Pareto, V. (2014). Manual of political economy: a critical and variorum edition , OUP Oxford. Pugh, A. (1976). An introduction to tensegrity , Univ of California Press. Song, K., Scarpa, F. & Schenk, M. (2022). Form-finding of tessellated tensegrity structures. Engineering Structures, 252 , 113627. Sterk, T. (2003). Using actuated tensegrity structures to produce a responsive architecture. ACADIA 2003 . UNHRC. (2016). Shelter Design Catalogue. Available: https://sheltercluster.org/resources/documents/shelter-design-catalogue [Accessed January 23rd 2024]. UNHRC. (2019). Shelter Solutions. Available: https://cms.emergency.unhcr.org/documents/11982/57181/Shelter+Design+Catalogue+January+2016/a891fdb2-4ef9-42d9-bf0f-c12002b3652e [Accessed January 23rd 2024]. Vierlinger, R. (2013). Multi objective design interface. Widyowijatnoko, A. & Harries, K. A. (2020). Joints in bamboo construction. Nonconventional and Vernacular Construction Materials. Elsevier. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 29 May, 2025 Read the published version in City, Territory and Architecture → Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5739117","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":437440864,"identity":"9905087e-efd0-4c30-b8e4-87842c40e2e2","order_by":0,"name":"Mia 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7","display":"","copyAsset":false,"role":"figure","size":210590,"visible":true,"origin":"","legend":"\u003cp\u003ePareto visualisation of 3D space of the first optimisation\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/ae4c4a1049dad70e36483d75.png"},{"id":79849968,"identity":"fc78840d-2068-4db1-a914-8abad3b38bff","added_by":"auto","created_at":"2025-04-03 14:24:05","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":63576,"visible":true,"origin":"","legend":"\u003cp\u003eThe shortest strut-optimised case (Figure 8a) and the lightest optimised case (Figure 8b)\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/aac6cfd346f6e6bc1a2256bf.png"},{"id":79851245,"identity":"4fba57d4-1e07-4213-a2a5-f4d916d20111","added_by":"auto","created_at":"2025-04-03 14:40:07","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":176683,"visible":true,"origin":"","legend":"\u003cp\u003eResults of the first optimisation:\u003c/p\u003e\n\u003cp\u003eThe optimised cases based on the number of occupants\u003c/p\u003e","description":"","filename":"9.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/e1db6c9bbfbc7e47e2a0421d.png"},{"id":79850003,"identity":"e9412dc6-0518-49f1-a418-aa984409c601","added_by":"auto","created_at":"2025-04-03 14:24:07","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":76069,"visible":true,"origin":"","legend":"\u003cp\u003e3-struts tensegrity structures with connection detail\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/38fcaba6d428147cfafdb72f.png"},{"id":79849964,"identity":"12a4f808-2121-4858-a776-f0d0110b17e5","added_by":"auto","created_at":"2025-04-03 14:24:05","extension":"png","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":482581,"visible":true,"origin":"","legend":"\u003cp\u003ePrototype 1\u003c/p\u003e","description":"","filename":"11.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/7816d423a120cdc534a6a506.png"},{"id":79850031,"identity":"96fcee23-508f-4b29-bf6d-e022901f5a82","added_by":"auto","created_at":"2025-04-03 14:24:09","extension":"png","order_by":12,"title":"Figure 12","display":"","copyAsset":false,"role":"figure","size":465620,"visible":true,"origin":"","legend":"\u003cp\u003ePrototype 2\u003c/p\u003e","description":"","filename":"12.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/fff7d48a06c0e242bd81f4e4.png"},{"id":79850614,"identity":"42215e16-e788-4a7f-8b2b-06f56e0b6e6f","added_by":"auto","created_at":"2025-04-03 14:32:08","extension":"png","order_by":13,"title":"Figure 13","display":"","copyAsset":false,"role":"figure","size":397795,"visible":true,"origin":"","legend":"\u003cp\u003eHabitable space\u003c/p\u003e","description":"","filename":"13.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/2bf1d2df46a833cf56d8358a.png"},{"id":79849956,"identity":"e797b041-7548-4512-8ac3-6d8d0f463386","added_by":"auto","created_at":"2025-04-03 14:24:05","extension":"png","order_by":14,"title":"Figure 14","display":"","copyAsset":false,"role":"figure","size":321772,"visible":true,"origin":"","legend":"\u003cp\u003ePareto visualisation of 3D space of the second optimisation\u003c/p\u003e","description":"","filename":"14.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/9783af85b489e917fb05c640.png"},{"id":79849955,"identity":"35111282-abaf-4dc6-97df-86e90767ceea","added_by":"auto","created_at":"2025-04-03 14:24:04","extension":"png","order_by":15,"title":"Figure 15","display":"","copyAsset":false,"role":"figure","size":80272,"visible":true,"origin":"","legend":"\u003cp\u003eThe shortest strut-optimised case (Figure 15a) and the lightest optimised case (Figure 15b)\u003c/p\u003e","description":"","filename":"15.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/1cc49d223a5e3d6f44b7685f.png"},{"id":79850014,"identity":"a1118b1a-0250-4175-bc5e-64723fa33363","added_by":"auto","created_at":"2025-04-03 14:24:08","extension":"png","order_by":16,"title":"Figure 16","display":"","copyAsset":false,"role":"figure","size":155999,"visible":true,"origin":"","legend":"\u003cp\u003eResults of the second optimisation:\u003c/p\u003e\n\u003cp\u003eThe optimised cases based on the number of occupants\u003c/p\u003e","description":"","filename":"16.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/3f942e9c1f4ace5f18f596f2.png"},{"id":79849954,"identity":"635988d2-a6c0-4b1a-b27d-35841b3e8a10","added_by":"auto","created_at":"2025-04-03 14:24:04","extension":"png","order_by":17,"title":"Figure 17","display":"","copyAsset":false,"role":"figure","size":66163,"visible":true,"origin":"","legend":"\u003cp\u003eThree-strut five-person shelter options\u003c/p\u003e","description":"","filename":"17.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/99855effe8748a21bff00834.png"},{"id":79850007,"identity":"972253a6-0425-45cd-a0f4-35a2dee4e117","added_by":"auto","created_at":"2025-04-03 14:24:08","extension":"png","order_by":18,"title":"Figure 18","display":"","copyAsset":false,"role":"figure","size":161329,"visible":true,"origin":"","legend":"\u003cp\u003eSolution 2.7, three-strut and sleeps five\u003c/p\u003e","description":"","filename":"18.png","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/cbfc6359bc0467568d004ef9.png"},{"id":83782803,"identity":"1e799e1a-effd-4992-b35b-18caeb1150af","added_by":"auto","created_at":"2025-06-02 16:06:20","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":5142288,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5739117/v1/11d53426-d16f-4600-9483-5607d43e49cd.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Multi-objective Optimisation of Bamboo Tensegrity Structure for Post-disaster Immediate Relief","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eThe number of natural disasters around the world is increasing, with in excess of 268\u0026nbsp;million people affected in the first decade of the millennium by 394 events, as reported in 2011 (Guha-Sapir et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2012\u003c/span\u003e). Globally, in the year of 2019, 398 natural disasters were recorded, with the Asia region suffering the most (40%), with floods and storms being the two deadliest types of disaster (CRED, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). In the year of 2023, 399 disasters related to natural hazards were recorded by the Emergency Events Database (EM-DAT), with the earthquakes in Turkey and Syrian Arab Republic in February 2023 as the most catastrophic event in 2023 based on mortality and economic damage (CRED, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). There is thus a growing need for emergency accommodation to provide shelter for those temporarily displaced by these events. In light of the current global situation in terms of both economic and climate-related factors, it is necessary that this provision be sustainable in both regards. While there are numerous existing solutions to this issue- emergency shelters are usually simply tents such as would be used for camping, and temporary shelters can be structures such as shipping containers, these historic solutions bring their unique problems. For instance, the logistical arrangements of transporting and situating shipping containers can be difficult in disaster-stricken areas and care must be taken to ensure their suitability, for example with regard to contaminants (Fari\u0026ntilde;a et al., \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). The economic and environmental costs associated with shipping bulky, heavy structural materials to affected areas can be exorbitant and this budget could be better spent on other aspects of disaster management such as establishing temporary infrastructure for food supply and medical care. While tents are a cheap and simple solution, their use-case scenarios are limited in terms of climate, temperature, substrate, local hazards, etc. The significance of the solution which is aimed to be developed during this research endeavour is that the bamboo tensegrity design is flexible and scalable to cater to spatial needs and therefore applicable to a wider range of contexts than the aforementioned solutions.\u003c/p\u003e \u003cp\u003eThe proposed shelter could potentially transcend the categorization which details only the emergency use classification, with the objective being that the rapid assembly process has become familiar prior to emergency use. The use of tensegrity structure is designed to minimize the number of elements in compression, thus simplifying both the design and the building process. The elements in tension in a tensegrity structure are straight, which simplifies the building process as there is no requirement for bending or forming joints. The structure can also be adaptable, depending on the number of compression elements and scalable depending on requirements or available materials. The application is also suggested in places where bamboo is abundant, hence structural elements are locally sourced, and it is easily transportable since only the tensile elements and skin might be imported to site. However, it should be noted that in areas where bamboo is not abundant, other materials can be substituted for the compression elements provided they are sufficiently lightweight and their compression strength equals or exceeds that of bamboo.\u003c/p\u003e \u003cp\u003eIn brief, this research aims to optimise a system of flexible shelter design for one to six people utilizing tensegrity structures which is quick to deploy, easily assembled by unskilled workers, and utilizes locally sourced, sustainable materials for the structural members, for instance, bamboo in the Asia Pacific region, an area historically hard-hit by extreme weather events such as typhoons and tsunamis. The research question is, \u003cem\u003e\u0026ldquo;What are the trade-offs in terms of structural and spatial arrangements to achieve an optimum habitable space?\u0026rdquo;\u003c/em\u003e\u003c/p\u003e"},{"header":"LITERATURE REVIEW","content":"\u003cp\u003eThe previous section has outlined the severity of the situation regarding to the global disasters and this relevant literature section elaborates on four main ideas, with an aim to position this research: the post-disaster relief shelters, tensegrity structure, bamboo tensegrity structure, and multi-objective optimisation.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePost-disaster relief shelters\u003c/h2\u003e \u003cp\u003eAccording to the United Nations Human Rights Council (UNHRC, henceforth), there are three stages to consider in the post-disaster scenario: the immediate relief period, the rehabilitation period and the reconstruction period (UNHRC, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). This tensegrity study looks at anticipation for the immediate relief period, the temporary shelters as first response. In the guidelines, \u0026lsquo;Shelter After Disaster\u0026rsquo; published by the Office for the Coordination of Humanitarian Affair of United Nations (IFRC, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2015\u003c/span\u003e), it is stated that there are disadvantages to tents which are usually distributed immediately following a disaster. The drawbacks include issues such as sanitation and amenities supply but also focuses on aspects such as lack of security and privacy.\u003c/p\u003e \u003cp\u003eIn the more recent UNHRC report (UNHRC, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2019\u003c/span\u003e), shelter design criteria encompasses: hazard risks and safety, timeliness and construction speed, lifespan, size and shape, privacy, security and cultural appropriateness, ventilation and thermal comfort, environmental considerations, cost effectiveness and standards and building codes. In addition, a local construction and the possibility for modification to suit individual needs are highlighted. Tensegrity structure is proposed to be able to meet some of the above-mentioned design criteria, particularly in terms of timeliness and construction speed.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eTensegrity structure\u003c/h3\u003e\n\u003cp\u003eTensegrity is a portmanteau word and stands for \u0026ldquo;tensional integrity\u0026rdquo;. The definition of tensegrity according to Pugh (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e1976\u003c/span\u003e), is that \u0026ldquo;a tensegrity system is established when a set of discontinuous compressive components interacts with a set of continuous tensile components to define a stable volume in space\u0026rdquo;. Three pioneers are often mentioned in relation to tensegrity, namely Buckminster Fuller, David Emmerich and lastly Kenneth Snelson who experimented with this system in the 1960s. Micheletti and Podio-Guidugli (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) provide a comprehensive 70 year review of tensegrities including more recent applications such as with a parametric approach to vaulted tensegrity networks (Liapi and Kim, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2004\u003c/span\u003e) and double layer tensegrity grid (Gomez-Jauregui et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). Anzalone et al. (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2017\u003c/span\u003e) proposed tensegrity as a solution to a rapidly deployable structure. They state the advantages of tensegrity structures as being self-erecting, efficient in terms of the number of members in compression, resilient, allowing for system flexibility and using standard linear (straight) elements. They also propose a system of computational design -RDAT- to simplify the design process. Abdelmohsen et al. (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) also used computational design in their research into tensegrity fa\u0026ccedil;ade design, and found that they could also generate curved skin surfaces using this method. On a related note, Sterk suggested than tensegrity can be used in responsive architecture to adapt to various weather conditions (Sterk, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2003\u003c/span\u003e). He posits moreover that depending on the actuators in the structure- the intersections of the tensile and compressional members- the structure can be designed to be resistant to earthquakes, high winds and other weather conditions. Song et al. (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) moreover propose a system of tessellated tensegrity structures which could be used to facilitate modular construction, further enhancing the adaptability of the system. While the historical perspective of tensegrity is not the focus of this paper, practical applications beyond conceptual design in the built environment are quite limited.\u003c/p\u003e \u003cp\u003eTo avoid confusion, in this study; the compressive elements made of full culm bamboo are called bamboo struts and the tensional elements are called cables. The design which the researchers adopted for the immediate relief shelter is the T-Prism, which is the simplest tensegrity structure. The coordinate system used is the cylindrical coordinate system, with reference to Burkhardt (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2008\u003c/span\u003e) as seen in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. In the unrotated (or untwisted) triangular prism, the height of the structure is equal to the length of the struts. This structure has no stability as the struts are constrained only in one direction (the tensional elements linking them at top and bottom). Rotating the structure allows for additional tensional elements to be placed between the top of the struts and the base of the adjacent struts. The geometry of the triangles thus formed dictates the resultant height of the structure and the extra constraint afforded by these extra elements in tension allows the structure to be freestanding. In terms of the design parameters, the geometry of the triangles is variable by rotating the prism to a greater or lesser degree, with commensurate changes in the lengths of the longer elements in tension (between the tops and bases of the adjacent struts).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\n\u003ch3\u003eBamboo tensegrity structure\u003c/h3\u003e\n\u003cp\u003eRegarding bamboo construction using tensegrity, Aditra and Widyowijatnoko (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) proposed a computational design system for a geodesic dome using a lattice structure, suggesting that bamboo is a suitable material for this application. They also devised a system of laser cutting joints which could be ported to those used in tensegrity structures. In a subsequent study, Widyowijatnoko and Harries (\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) also researched bamboo as a building material and examined various methods of forming joints. They found that bamboo has excellent tensile strength and stiffness, having an ultimate tensile strength of between 31 and 85 N/mm\u003csup\u003e2\u003c/sup\u003e and while there is considerable variation due to the non-standard nature of the material, this is almost certainly adequate for the compression loads in a tensegrity structure which are lower than in a structure built purely in compression. Their exhaustive work on joints however is arguably of greater interest, because through a combination of vernacular construction techniques and engineered joints, they have discovered ways to mitigate the stresses in the modes where bamboo is weakest. The use of bamboo for compression members in this paper is to challenge documented obstacles to practical application of tensegrity technology (Burkhardt, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2008\u003c/span\u003e). The obstacles include strut congestion, poor load response, fabrication complexity and inadequate design and analysis tools.\u003c/p\u003e\n\u003ch3\u003eMulti-objective Optimisation\u003c/h3\u003e\n\u003cp\u003eIn comparison with a single-objective optimisation which produces a single solution; multi-objective optimisation deals with multiple conflicting objectives which need to be optimised concurrently. Moroni et al. (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2024\u003c/span\u003e) state that due to the conflict which can arise from having two or more objectives, multi-objective optimisation can rely on preference-based methods or Pareto optimisation for resolution. The former assumes bias or preference on the part of the designer while the Pareto approach described below accepts that no single solution can improve one aspect of a problem or situation without causing deterioration in another.\u003c/p\u003e \u003cp\u003eOne of the earliest contributions to knowledge came from Vilfredo Pareto, a French Italian economist who introduced the concept of Pareto efficiency in the late 19th century, as documented in the updated translation of the manual (Pareto, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). His 80\u0026thinsp;\u0026minus;\u0026thinsp;20 rule states that up to a certain point, 80% of results can be achieved with 20% of effort, suggesting that anything in excess of a nominally 80% \u0026ldquo;perfect\u0026rdquo; solution will require exponentially increased effort. The main idea of Pareto was that in the face of conflicting goals and limited resources, the optimal solution can be defined as being imperfect- a compromise between these conflicting goals, or rather a set of compromises. Thus, one goal cannot be achieved without degrading another outcome, as mentioned previously, and the optimal outcome is, of necessity, a trade-off. The Pareto principles were adopted to computational optimisation methods with evolutionary algorithms, in particular in terms of negotiation of conflicting goals.\u003c/p\u003e \u003cp\u003eEvolutionary multi-objective optimisations, according to Deb (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2011\u003c/span\u003e), take solutions based on several different criteria which are then used to populate datasets for the next iteration of solutions. This population-based approach is what differentiates evolutionary multi-objective optimisations from evolutionary single-objective optimisations. A typical approach uses a generation engine, often using parametric design, which feeds into an evaluation engine. Both of these engines feed their results into an exploration engine, which uses evolutionary algorithms.\u003c/p\u003e \u003cp\u003eIn a comprehensive literature review by Moroni et al. (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2024\u003c/span\u003e), it was mentioned that multi-objective optimisation is used in different fields related to built environment. In architecture, it is applied to problems in environmental comfort, layout distribution or shape. For sustainability issues, there is tension in the goals between environmental and economic considerations, and although not explicitly mentioned in the Moroni article, arguably social sustainability is also a potentially conflicting goal within the overarching objective of sustainability. Of relevance to this current research is the application of multi-objective optimisation to the following variables identified by Moroni et al, all of which have the potential to generate tension in the manner described by Pareto. In terms of structure, there are: structural design, structural performance (including deformation and displacement), and geometry or topology. Under architecture, the considerations are broadly similar for the purposes of the proposed emergency shelters. Under materials, there are: building\u0026rsquo;s elements, its characteristics, and its quantities. Moreover, there are more specific variables which include: building height, geometry of floorplan, interior space vs. external volume, envelope shape and materials, number of structural elements, design appearance, and cost. It is probable that the Pareto principle applies here since many of these considerations cannot be optimised without detriment to other goals. Interestingly, in the Moroni study, only 42 out of the 203 reviewed articles stated that combination of objectives from different categories was not a goal of the multi-objective optimisation process, which possibly suggests that the Pareto principle was followed in the majority of cases (Moroni et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2024\u003c/span\u003e).\u003c/p\u003e"},{"header":"RESEARCH METHODOLOGY","content":"\u003cp\u003eThis research adopts a multi-phase methodology based on \u0026lsquo;Iterative Multicriteria Simulation and Prototyping Optimisation\u0026rsquo; (Ni\u0026ntilde;o-P\u0026eacute;rez et al., \u003cspan class=\"CitationRef\"\u003e2017\u003c/span\u003e). This approach integrates computational simulation, multi-objective optimisation, and full-scale prototyping in iterative cycles to systematically evaluate and refine the design process. The research is structured into three main stages: (1) computational simulation followed by multi-objective optimisation, (2) full-scale prototyping, and (3) a second round of multi-objective optimisation informed by prototype evaluations.\u003c/p\u003e\n\u003cp\u003eIn the first stage, computational simulations were conducted to assess the performance of five design parameters. A multi-objective optimisation process was then applied to identify the characteristic of the most effective solutions based on predefined objectives, including amount of habitable space provided (measured by number of occupants), overall weight and each bamboo strut\u0026rsquo;s length.\u003c/p\u003e\n\u003cp\u003eThe second stage involved the construction and evaluation of two full-scale prototypes to assess the feasibility and practicality of the optimised design under different material configurations. Both prototypes maintained identical dimensions but varied in terms of joints and cable materials: one utilized steel cables for greater tensile strength, while the other employed braided nylon cord for its wider availability of non-specialist joints. This comparison provided critical insights into how different material choices impact the predefined objectives.\u003c/p\u003e\n\u003cp\u003eIn the third stage, reflections and evaluations from the prototyping stage provided critical insights into the structure\u0026rsquo;s functionality, assembly efficiency, and overall performance. Based on these findings, a second round of multi-objective optimisation was revised and conducted, incorporating feedback to refine the design further, enhancing its efficiency.\u003c/p\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003eDesign Parameters\u003c/h2\u003e\n \u003cp\u003eThe selected tensegrity structure for the immediate relief shelter is the T-Prism, and its design of the T-Prism tensegrity is defined by five key design parameters: (1) the number of bamboo struts, (2) the overall height of the structure, (3) the degree of rotation of the bamboo struts, (4) the radius of the top section, and (5) the radius of the bottom section. The specific range and increments assigned to each parameter are detailed in Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e, providing a framework for systematic exploration and optimisation of the design. In this study, the number of bamboo struts is limited to a maximum of six, considering the assembly process. This constraint ensures that each strut can be held in place by a single person until the structure reaches equilibrium, facilitating a more practical and manageable construction process. The radius of the top and bottom areas are critical design parameters that directly impact the habitable area. As illustrated in Fig. \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e above, when the top and base areas (A\u0026rsquo;-B\u0026rsquo;-C\u0026rsquo; and A-B-C) are identical, the efficiency of the usable space is reduced. In contrast, a structure with a more tapered, \u0026lsquo;pointed\u0026rsquo; top optimises the internal space, improving both spatial efficiency and structural balance (and potentially wind resistance, though this was impossible to assess in this study due to the lack of skin or fa\u0026ccedil;ade). Figure \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e illustrates the design parameters (x\u003csub\u003e1\u003c/sub\u003e-x\u003csub\u003e5\u003c/sub\u003e).\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eDesign parameters\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"4\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDesign Parameters\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eLower Limit\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eIncrements\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eUpper Limit\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e1\u003c/sub\u003e: The number of bamboo struts\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e2\u003c/sub\u003e: The overall height (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e3\u003c/sub\u003e: The degree of rotation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e90\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e4\u003c/sub\u003e: The radius of the top section (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e5\u003c/sub\u003e: The radius of the bottom section (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003ch3\u003eDesign Performance\u003c/h3\u003e\n\u003cp\u003eThis study focuses on two key aspects: spatial needs and portability. Regarding spatial needs, the immediate relief shelters are designed primarily for sleeping, similar to camping tents. The research evaluates the habitable area (Y1) based on the number of occupants, which is set at a maximum of six individuals\u0026mdash;the typical size of a family. This assessment ensures that the shelter provides adequate space for basic rest and protection while maintaining a compact and efficient footprint suitable for emergency use. To determine the spatial requirements for individual occupants, this study uses a standard camping mat size of 65 cm \u0026times; 183 cm (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e) as a reference for a single sleeping space. The overall head clearance for one person is 1.25 m in height, ensuring sufficient comfort while lying down.\u003c/p\u003e\n\u003cp\u003eRegarding portability, this research evaluates two key criteria: the overall weight (Y2) and length (Y3) of each bamboo struts. The overall weight is calculated based on an 8 cm diameter full-culm \u003cem\u003eGigantochloa apus\u003c/em\u003e, a species commonly used in construction and native to Southeast Asia. It has a high strength-to-weight ratio, making it well-suited for portable structures. The length of the bamboo struts directly impacts the portability of the structure. Shorter components are easier to handle, pack, and transport, particularly in emergency scenarios where rapid deployment is crucial. Although the weight of the hardware- cables, tensioners, etc.- is not unsubstantial, it was regarded as of only incidental importance to these calculations and has thus not been included.\u003c/p\u003e\n\u003ch3\u003eComputational Modelling and Simulation\u003c/h3\u003e\n\u003cp\u003eThe modelling and simulation were conducted using Grasshopper\u0026trade;/Rhinoceros 3D\u0026trade;, where custom scripts were developed to generate and analyse the tensegrity structure. The geometrical modelling process, as illustrated in Fig. \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e, was scripted in Grasshopper to ensure flexibility in exploring various configurations. Once the geometrical modelling\u0026rsquo;s script was established, performance simulations were conducted, as shown in Fig. \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e, to evaluate the predefined objectives. The computational approach is used to allow rapid iteration and optimisation, the following stage.\u003c/p\u003e\n\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\n \u003ch2\u003eMulti-objective Optimisation\u003c/h2\u003e\n \u003cp\u003eThe multi-objective optimisation in this study is designed to achieve an optimal balance between three key criteria: maximising the number of occupants while minimising both the total weight and length of the bamboo components, as shown in Eq. 1 below. This analysis is performed using Octopus, a multi-objective optimisation plugin for Grasshopper\u0026trade; (Vierlinger, \u003cspan class=\"CitationRef\"\u003e2013\u003c/span\u003e), which leverages evolutionary algorithms to explore and refine potential design solutions.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\n \u003ch2\u003eEquation 1\u003c/h2\u003e\n \u003cp\u003e\u003cspan class=\"InlineEquation\"\u003e\u0026nbsp;\u003cspan class=\"mathinline\"\u003e\\(\\:Minimize\\:F\\)\u003c/span\u003e\u0026nbsp;\u003c/span\u003e \u003cem\u003e= (-\u003c/em\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:f\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e1\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e(\u003c/em\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:x\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e1\u003c/em\u003e\u003c/sub\u003e,\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:x\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e,\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:x\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e3\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e)\u003c/em\u003e,\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:f\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e(\u003c/em\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:x\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e1\u003c/em\u003e\u003c/sub\u003e,\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:x\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e,\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:x\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e3\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e)\u003c/em\u003e, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:f\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e3\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e(\u003c/em\u003e\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:x\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e1\u003c/em\u003e\u003c/sub\u003e,\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:x\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e,\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:x\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e3\u003c/em\u003e\u003c/sub\u003e\u003cem\u003e))\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003ewhere F represents the set of solutions, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:f\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e1\u003c/em\u003e\u003c/sub\u003e corresponds to the objective of maximizing the habitable area, which is multiplied by -1 to transform it into a minimization problem, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:f\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e2\u003c/em\u003e\u003c/sub\u003e represents the objective of minimizing the total weight of the bamboo components, and \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:f\\)\u003c/span\u003e\u003c/span\u003e\u003csub\u003e\u003cem\u003e3\u003c/em\u003e\u003c/sub\u003e denotes the objective of minimizing the length of the bamboo components. While \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:x\\)\u003c/span\u003e\u003c/span\u003e denotes the design parameters, defining the possible configurations of the structure (see Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). The optimisation process generates a wide range of possible configurations, evaluating each based on the defined objectives. The results are then visualized in a three-axis graph, where solutions are mapped to identify the Pareto front\u0026mdash;a set of non-dominated solutions representing the best trade-offs among competing objectives (Ehrgott, \u003cspan class=\"CitationRef\"\u003e2005\u003c/span\u003e).\u003c/p\u003e\n\u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eThis section provides a descriptive account of investigations conducted through the three-stage iterative multicriteria simulation and prototyping. This section specifically examines how changes in five design parameters (x\u003csub\u003e1\u003c/sub\u003e-x\u003csub\u003e5\u003c/sub\u003e) are considered, evaluated and implemented which as a result, influences the three design performance criteria (Y1, Y2, and Y3).\u003c/p\u003e\n\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\n \u003ch2\u003eStage 1: Multi-objective Evolutionary Optimisation 1\u003c/h2\u003e\n \u003cp\u003eThe optimisation was conducted using Octopus, employing the NSGA-II algorithm with HypE-based reduction and mutation. The results, shown in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e, consist of 20 optimised cases generated in the 100th generation. The three axes refer to the three previously mentioned evaluation criteria: habitable areas (Y1- green axis), total weight (Y2- blue axis) and strut\u0026rsquo;s length (Y3- red axis).\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eOptimised cases of the first optimisation\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"9\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eOptimum Cases\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"5\"\u003e\n \u003cp\u003eDesign Parameters\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003ePerformances\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e4\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e5\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY1\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY2\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY3\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNo of bamboo struts\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall height (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDegree of rotation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRadius of the top section (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRadius of the bottom section (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eHabitable area (no of person)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall weight of bamboo (kg)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eLength of each bamboo strut (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e26.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.98\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e25.49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.76\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e24.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.63\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e24.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.59\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e23.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.51\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e24.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.34\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e23.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.17\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e22.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e20.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.58\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e22.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.89\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e20.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.56\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e19.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.38\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e19.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.21\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e16.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.63\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e16.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.62\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e19.46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5.74\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e19.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5.65\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e17.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e15.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.48\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e14.03\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.14\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003eIn Fig. 8a, the shortest strut-optimised case, Solution 1.5 fulfil the Y3 criteria the most, which is optimised for the shortest strut length. This solution features six of 3.5 m struts, weighs approximately 24 kg, and accommodates two people. Meanwhile, in Fig. 8b, the lightest optimised case, Solution 1.20 fulfil the Y2 criteria the most. This lightest optimised design was selected for further analysis in Stage 2. Weighing 14 kg, it consists of three of 4.1 m bamboo struts, has an overall height of 3 m, and is designed for one person sleeping. Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e and Fig. 9 show solutions of each occupancy rate with fewest number of bamboo struts for the first optimisation.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eThe optimised cases based on number of occupants (first optimisation)\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"12\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eOptimum Cases\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"6\"\u003e\n \u003cp\u003eDesign Parameters\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"5\"\u003e\n \u003cp\u003ePerformances\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e4\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e5\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eY1\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY2\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003eY3\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNo of bamboo struts\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall height (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eDegree of rotation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRadius of the top section (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRadius of the bottom section (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eHabitable area (no of person)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall weight of bamboo (kg)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eLength of each bamboo strut (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e1.20\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e(selected)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e3.0\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003e36\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e0.8\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e2.1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e14.03\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e\u003cstrong\u003e4.14\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e15.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e4.48\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e19.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e4.21\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e19.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e5.65\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e19.46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e5.74\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e22.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003e4.89\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\n \u003ch2\u003eStage 2: Prototyping\u003c/h2\u003e\n \u003cp\u003eIn the second stage, Solution 1.20 from the initial optimisation was measured to assess its assembly and disassembly ease, design parameters, and performance. Two 1:1 scale physical prototypes were assembled. The two prototypes shared the same dimensions and mainly differed in the types of joints and cabling (Fig. 10). Based on the bamboo and cable length data from Grasshopper, the materials were prepared. Bamboo lengths were extended by 10 cm on each end to prevent cracking around bolt holes, while cable lengths were extended by 20 cm on each end.\u003c/p\u003e\n \u003cp\u003eEach prototype was pitched at least twice with tensional elements (cables or rope) already attached to bamboo struts. They were pre-assembled on the ground and moved to the target location. The three bamboo struts (4.1 m long) took two people to carry, and once pitched the tectonic (only bamboo struts and cables, without skin) system can be moved by one person. This illustrates the mobility of the tectonic elements.\u003c/p\u003e\n \u003cp\u003eThe first prototype used steel cables attached to an eyelet bolt passed through the 8cm in diameter Apus bamboo struts with an eyelet nut on the other end via steel cable tensioners as noted above, refer to Fig. 11. During the second pitch exercise, the authors noted that most of the 24 joints can be fixed joints particularly the top triangle and the bottom triangle shaped cables, with the exception of the three diagonal cables. This will decrease the post-tensioning duration. In total the first prototype was assembled and disassembled three times, and the total time to pitch decreased from eight to seven minutes on the last assembly as the researchers became familiar with the assembly steps. On an incidental note, the assembly sequence can perhaps be standardised for future builds for ease of assembly.\u003c/p\u003e\n \u003cp\u003eThe second prototype (Fig. 12) utilised simple screwgate karabiners or D shackles, attached to the same diameter (8cm) Apus bamboo via doubled cord lashing. Braided nylon cord was used because it is widely available worldwide and requires no special tools to work with. This is particularly germane because specialist equipment and hardware is not readily and economically available everywhere in the world, especially in emergency situations. The doubled cord was pre-stretched to achieve its non-stretchy state (also to maintain the accuracy of measurement), and surprisingly, the stretching rate was 46%. This results in 8mm diameter cord reducing to 5mm. Post-tensioning needed to be carried out in mini steps, ensuring the three struts were adjusted at the same time or in sequence. The difference between prototypes 1 and 2 in this regard is that due to the elastic nature of the braided nylon cord, the post-tensioning process took more time.\u003c/p\u003e\n \u003cp\u003eFrom the two prototypes, it can be observed that, in terms of habitable area, computational modelling suggested that the prototype could accommodate one person. However, during prototyping, it was observed that it could accommodate two people (Fig. \u003cspan class=\"InternalRef\"\u003e13\u003c/span\u003e). Assembling the tensegrity structure to a self-standing state took approximately eight minutes, with an additional five minutes required to tension the cables. Disassembly took less than one minute for both prototypes. The number of people required for assembly and disassembly matched the number of struts\u0026mdash;three in this case. For easy reference, a comparative summary is provided in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab4\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparative summary of Prototype 1 and Prototype 2\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"2\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePrototype 1:\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePrototype 2:\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e▪ The use of more specific hardware such as steel cables and tensioners\u003c/p\u003e\n \u003cp\u003e▪ Quick post-tensioning process\u003c/p\u003e\n \u003cp\u003e▪ Pre-stretching tensional elements- the cables- is not necessary\u003c/p\u003e\n \u003cp\u003e▪ Measurements can be maintained as blueprints\u003c/p\u003e\n \u003cp\u003e▪ Stiffness of structure is ensured\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e▪ Widely available/ easy to find hardware\u003c/p\u003e\n \u003cp\u003e▪ Post-tensioning process can be as long as pitching (seven to eight minutes)\u003c/p\u003e\n \u003cp\u003e▪ Rope needs to be pre-stretched\u003c/p\u003e\n \u003cp\u003e▪ Accuracy of the measurements is difficult to maintain due to the stretchy character of the rope\u003c/p\u003e\n \u003cp\u003e▪ Structure is easy to flex\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\n \u003ch2\u003eStage 3: Multi-objective Evolutionary Optimisation 2\u003c/h2\u003e\n \u003cp\u003eThe third stage aimed to rectify the design parameters based on results from Multi-Objective Optimisation stage 1 and insights from Prototypes 1 and 2. Adjustments were made as follows; the summary is presented in Table \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e:\u003c/p\u003e\u003cspan\u003e\n \u003cp\u003e1. Number of bamboo struts: Optimised cases (Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e) initially had 3 to 4 struts. Then, the range was adjusted from 3\u0026ndash;6 struts to 3\u0026ndash;4 struts.\u003c/p\u003e\n \u003c/span\u003e \u003cspan\u003e\n \u003cp\u003e2. The overall height: Since all optimised cases (Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e) had a height of 3 m (the minimum lower limit), the total height range was lowered to 2.0\u0026ndash;3.0 m.\u003c/p\u003e\n \u003c/span\u003e \u003cspan\u003e\n \u003cp\u003e3. The degree of rotation: Optimised cases indicated possible strut-cable intersections due to a small rotation degree. To address this, a new script was added to incorporate clash detection, eliminating cases where intersections were detected.\u003c/p\u003e\n \u003c/span\u003e \u003cspan\u003e\n \u003cp\u003e4. Top section radius: The optimised cases (Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e) showed a top radius range of 0.8\u0026ndash;1.1 m. The maximum was set at 1.1 m, with an adjusted range of 0.2\u0026ndash;1.1 m.\u003c/p\u003e\n \u003c/span\u003e \u003cspan\u003e\n \u003cp\u003e5. Bottom section radius: The optimised cases had a bottom radius of 2.1\u0026ndash;3.9 m. Observations from the prototypes (Fig. \u003cspan class=\"InternalRef\"\u003e13\u003c/span\u003e) showed that, despite being designed for one person, the structures provided ample space for two people. Thus, the minimum bottom radius was reduced from 2.0 m to 1.0 m, corresponding to the length of a standard sleeping mat.\u003c/p\u003e\n \u003c/span\u003e\n \u003cp\u003eAdditionally, the sitting height was lowered from 1.25 m to 0.9 m. The initial 1.25 m estimate was based on tent dimensions with sloped sides, so maximum head height is available only in the centre of the tent, whereas observations indicated a lower height would be sufficient. The sleeping area remained unchanged, referencing a standard sleeping mat size of 65 cm \u0026times; 183 cm. The second stage of optimisation yielded 11 optimised cases, as shown in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e14\u003c/span\u003e. However, none of these cases could accommodate six people.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab5\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eRefined design parameters\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"4\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDesign Parameters\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eLower Limit\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eIncrements\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eUpper Limit\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e1\u003c/sub\u003e: The number of bamboo struts\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e2\u003c/sub\u003e: The overall height (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e3\u003c/sub\u003e: The degree of rotation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e115\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e4\u003c/sub\u003e: The radius of the top section (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e5\u003c/sub\u003e: The radius of the bottom section (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\u0026nbsp;\u003ctable id=\"Tab6\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eOptimised cases of the second optimisation\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"9\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eOptimum Cases\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"5\"\u003e\n \u003cp\u003eDesign Parameters\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003ePerformances\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e4\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e5\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY1\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY2\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY3\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNo of bamboo struts\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall height (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDegree of rotation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRadius of the top section (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRadius of the bottom section (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eHabitable area (no of person)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall weight of bamboo (kg)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eLength of each bamboo strut (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e19.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.37\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e18.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.83\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.61\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.96\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.78\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.74\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.82\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.63\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003eSimilarly with Stage 1, several solutions are presented below illustrating the most optimal solutions based on each performance criterion. In Fig. 15a, the shortest strut-optimised case, Solution 2.6 fulfils the Y3 criteria the most, which is optimised for the shortest strut length. This solution features six of 2.78 m struts, weighs approximately 12.55 kg, and accommodates one person. Meanwhile, in Fig. 15b, the lightest optimised case, Solution 2.11 fulfils the Y2 criteria the most. Weighing 12.31 kg, this solution consists of three of 3.6 m bamboo struts, has a height of 2.0 m, and is designed for one person sleeping. In terms of habitable area, the optimised cases were analysed based on occupant capacity (Y1), shown in Table \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e and Fig. 16. The data was grouped by the number of occupants, selecting the case with the fewest bamboo struts.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab7\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 7\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eThe optimised cases based on number of occupants (second optimisation)\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"9\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eOptimum Cases\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"5\"\u003e\n \u003cp\u003eDesign Parameters\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003ePerformances\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e4\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e5\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY1\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY2\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY3\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNo of bamboo struts\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall height (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDegree of rotation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRadius of the top section (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRadius of the bottom section (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eHabitable area (no of person)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall weight of bamboo (kg)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eLength of each bamboo strut (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.63\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.82\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.74\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.06\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\n \u003c/div\u003e\n\u003c/div\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eWhile the Results section considers how changes in five design parameters (x\u003csub\u003e1\u003c/sub\u003e-x\u003csub\u003e5\u003c/sub\u003e) are evaluated and implemented, this section examines how improvements in performance are achieved as a result of the iterative simulation and optimisation. To summarise the changes, Table \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e provides a comparative design parameters data as recorded in first optimisation and second optimisation. It shows that the evolution of the system design is optimised further by changing the upper limits of x\u003csub\u003e1\u003c/sub\u003e-x\u003csub\u003e4\u003c/sub\u003e (marked in blue fonts) variables and the lower limit of x\u003csub\u003e2\u003c/sub\u003e (marked in orange fonts) variables. The rest of the discussion related to improvements will be expanded based on the three performance criteria, followed by reflections on the suitability of bamboo for compression members in tensegrity structure. In general, the second optimisation produces fewer optimum solutions (11 solutions) in comparison with the first optimisation (which yielded 20 solutions). Second optimisation also eliminated the need for five-strut and six-strut structures and suggested three-strut and four-strut arrangements only.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab8\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 7\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison of design parameters, first and second optimisation\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"5\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eFirst optimisation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eSecond optimisation\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDesign Parameters\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eLower Limit (Stage 1)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eUpper Limit (Stage 1)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eLower Limit (Stage 3)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eUpper Limit (Stage 3)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e1\u003c/sub\u003e: The number of bamboo struts\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e2\u003c/sub\u003e: The overall height (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e3\u003c/sub\u003e: The degree of rotation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e115\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e4\u003c/sub\u003e: The radius of the top section (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ex\u003csub\u003e5\u003c/sub\u003e: The radius of the bottom section (m)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.0\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\n \u003ch2\u003eThree design performance criteria\u003c/h2\u003e\n \u003cp\u003eThe two key aspects are the spatial needs and portability, which is translated into objectives in the simulations and optimisations into evaluation of habitable area based on the number of occupants (Y1), the overall weight of the main structure (Y2) and length of each bamboo strut (Y3).\u003c/p\u003e\n \u003cp\u003eFirstly, in terms of the habitable area (Y1 performance criteria) which is measured by the number of occupants, one of the main results derived from the second optimisation is that optimum cases do not fulfil occupancy rate of six persons. This might be due to the fact that with the decrease in height and the slope of the sides, the floor area is reduced in terms of acceptable head height (already reduced from 1.25m to 0.9m). From the first optimisation it is found that to achieve higher numbers of occupants does not always require higher number of bamboo struts. For example for five occupants, Solution 1.16 (first optimisation, refer to Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e) requires three struts, weighs 19.46kg with a compromise of 5.74m long struts. The counterpart in the second optimisation of three struts and sleeps five, Solution 2.7 (Table \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e), has an overall weight of 17.98 kg with 5.30m long struts. Both solutions have a trade-off regarding extremely long bamboo struts which might reduce the ease of transporting in a normal truck. The second optimisation, however, shows that a three-strut arrangement can fulfil a wide range of occupancy levels, from one to five occupants which requires bamboo poles between 3.63m to 5.30m. It is also worth noting that the second optimisation produces the most five-person shelter options with three solutions (Solution 2.1, 2.2 and 2.7). Figure 17 and Table \u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e show comparison of three-strut optimum cases for five occupants, Solution 1.16 (from first optimisation) with Solution 2.7 (from second optimisation). As comparison, the corresponding solution in second optimisation provided more effective structure in terms of lower overall height, and also smaller radius on both top and bottom. This also results in lower overall weight and shorter struts.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab9\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 8\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eThree-strut five-person shelter options: first and second optimisations\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"9\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"3\"\u003e\n \u003cp\u003eOptimum Cases\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"5\"\u003e\n \u003cp\u003eDesign Parameters\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003ePerformances\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e3\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e4\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003ex\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e5\u003c/strong\u003e\u003c/sub\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY1\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY2\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eY3\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNo of bamboo struts\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall height (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDegree of rotation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRadius of the top section (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eRadius of the bottom section (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eHabitable area (no of person)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall weight of bamboo (kg)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eLength of each bamboo strut (m)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e19.46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.74\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e17.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.30\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003cdiv align=\"left\" class=\"colspec\"\u003e\u003cbr\u003e\u003c/div\u003e\n \u003c/div\u003e\n \u003cp\u003eFigure 18 shows the simulated possibility utilising sleeping mat (habitable space) dimensions as reference, using Solution 2.7. Storage space is also included in the simulation, shown as shaded area inside the structure with a height of 1m. It is also noted during the research that sleeping positions of six as posited in Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e that the higher number of occupants, the more internal circulation space is required. Although the provision for preliminary study is sufficient, further attention should be given to space arrangement mainly for shelters which are to accommodate three to five occupants.\u003c/p\u003e\n \u003cp\u003eSecondly, in terms of overall weight of bamboo (Y2 performance criteria). In general, the range of total weight was reduced from the first to the second optimisation. The first optimisation sees a range of 14 kg (one person) to 25.50 kg (five person) to 26.98 kg (six person); whereas the second optimisation sees a range of 12.3 kg (one person) to 19.78 kg (for five person). Factors affecting the significant reduce of the total weight are the reduced upper limit of overall height (x\u003csub\u003e2\u003c/sub\u003e) and the reduced upper limit of bamboo struts from six to four in second optimisation. It can be predicted that the higher number of occupants, the lower the weight per person is. However, from Table \u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003e, the four-person optimised solutions have the same ratio as the five person solutions, might suggest fact that the five-person shelters have most favourable ratio between weight and number of occupants.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab10\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 9\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eWeight/person according to occupancy (second optimisation)\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"3\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSolution no\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOccupancy (person)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eWeight/person (kg)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.1, 2.2 and 2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.3 and 2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.4 and 2.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.5 and 2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u0026ndash;7\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.6 and 2.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e12\u0026ndash;13\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003eBased on the observations during Prototype 1 and 2 which show a tensegrity for one person derived from Solution 1.20\u0026rsquo;s dimensions, two people can lift three poles of option 1.5 (4.1m long struts), stacked together. The first optimisation, Stage 1, shows that the total weight of this structure is 14 kg. In comparison, a safe weight for one person handling is generally considered to be 25kg. The structure came under this safe weight, however, due to the length of each bamboo strut; it was as a result unstable to be carried by one person. It took two people to carry the struts with all cables attached, one at each end; and took three people (basically one person per strut) to hold the struts until the structure reached equilibrium which took seven minutes. Thus, a one-person shelter required two people to carry and three people to pitch. This shows that from the practicality aspect of assembling the tensegrity structure, it can be crucial to suggest the most optimum solution(s). Subsequently in Stage 3 (second optimisation), two solutions for one-person-shelter are Solution 2.6 which is four-strut and Solution 2.11 which is three-strut. Both solutions weigh approximately the same despite the difference number of struts, between 12.3kg to 12.6 kg which is lower from the first optimisation of 14 kg. The difference in assembly is that the four-strut solution requires more people (four at minimum) compared to the three-strut which requires three people to pitch following the one-strut-one-person-to-hold concept.\u003c/p\u003e\n \u003cp\u003eThirdly, related to each strut\u0026rsquo;s length (Y3 performance criteria), this can also suggest the amount of materials needed. Apart from the transport issue, for bamboo struts which are too long (more than 4.5m), the anticipated issues are difficulty to find the culms and the compromised stiffness of the tectonic system. Moreover, bamboo poles are not perfectly straight and usually tapered at one end. The longer the culm is, the possibility to have a slightly curved strut is higher. In the experience of the researchers, longer culms may also be prone to buckling under compression load. From the first optimisation, the shortest strut is 3.51m (Solution 1.5) and the longest strut is 5.74m (Solution 1.16). From the second optimisation the shortest strut is 2.78m (Solution 2.6) and the longest strut is 4.37m (Solution 2.1). The refined five design parameters, shown in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e, illustrate that the second optimisation allows solutions to be within the range of acceptable length, less than 4.5m. The shortest strut suggested in the second optimisation is also in accordance with Stage 2 experience to not have the strut more than 2.8 m long for easy portability by one person.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec19\" class=\"Section2\"\u003e\n \u003ch2\u003eBamboo for tensegrity structures\u003c/h2\u003e\n \u003cp\u003eThe second part of this discussion looks at general observations of the use of bamboo for this type of unique structure. This shelter design addresses several design criteria according to UNHRC (\u003cspan class=\"CitationRef\"\u003e2019\u003c/span\u003e)\u0026rsquo;s report, particularly the environmental considerations, the use of local materials and cost effectiveness, with the use of full culm bamboo poles in places where bamboo is abundant, rather than waiting for imported tents to be shipped over high mileages to disaster zones. This study also supports what Anzalone et al. (\u003cspan class=\"CitationRef\"\u003e2017\u003c/span\u003e) proposed, a tensegrity as a solution for a rapidly deployable structure. The effectiveness in terms of number of members in compression and allowing flexibility using straight elements (which is an inherent characteristics of full culm bamboo poles) is illustrated through this preliminary study. The lightweight structure is easy to transport and move even once it is in pitched condition (without skin or fa\u0026ccedil;ade). This exploration also puts tensegrity as a practical and yet feasible solution for post-disaster immediate relief. In addition, the structure is considered to be self-build, thus allowing for further modification by the occupants.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eThis study illustrates the possible utilisation of full culm bamboo poles as compression members in tensegrity structures for the purpose of immediate relief shelters. This paper addresses key shelter design criteria (UNHRC, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2019\u003c/span\u003e) in terms of timeliness and construction speed, cost effectiveness and the use of local material use for places where bamboo is in abundant, the lack of availability of specialist hardware and tools (the alternative materials and hardware), easy transportability (by two people) and easy relocation once it is pitched by one person. This study also challenges the four primary obstacles of practical applications of tensegrity structures (Burkhardt, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2008\u003c/span\u003e), in particularly the challenge of inadequate design and analysis tools. The authors utilised a multi-phase methodology which includes combination of iterative multicriteria simulation and prototyping optimisation.\u003c/p\u003e \u003cp\u003eThe key findings from this research are that with increasing Pareto front optimisations, the occupancy rate decreases (none of the second round of optimised designs was capable of accommodating six people). There is also the consideration of using longer lengths of bamboo in terms of structural issues (being prone to buckling), transportation (since a truck might typically accommodate 4.5 metre lengths, and a sole person can realistically move lengths of up to 2.8 metres) and sourcing a sufficient number of straight culms. A further issue identified was that using polypropylene rope for the cable and tension system introduces a new set of complexities, since the rope tested in this research stretched by over 40%. While the focus of this study was on using bamboo, it should also be acknowledged that this solution is limited to certain geographical areas and while it may reasonably be assumed that other alternative materials with similar mechanical properties would perform similarly, this was not tested in this study.\u003c/p\u003e \u003cp\u003eTo reiterate the research question, it is \u003cem\u003e\u0026ldquo;What are the trade-offs in terms of structural and spatial arrangements to achieve an optimum habitable space?\u0026rdquo;.\u003c/em\u003e Reference to Table\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e6\u003c/span\u003e (second optimisation, in the results section) shows that when Y1 (habitable area) is high, Y2 and Y3 (overall weight and length, respectively) tend to be poor. However, there is more variance in Y3 than in Y2 which tends to have a relatively close linear relationship with Y1. The optimal compromise seems to be between Y1\u0026thinsp;=\u0026thinsp;4 and Y1\u0026thinsp;=\u0026thinsp;5. Thus, these shelters, based on requirements, are possibly best suited to these occupancy rates. For single or dual occupancy, options are limited because of the lengths of the culms required and the fact that two people are required to pitch these designs. For occupancy rates of six or more, the length of culms required becomes too great. Optimisation can be focused on shorter lengths of bamboo struts for easy transport by one or two people, while for the three to five-person shelters, the number of occupants need to be equal to or more than the number of bamboo struts for ease of disassembly. The trade-offs in terms of structural and spatial arrangements can be considered from two extremes. One side of the extreme is occupancy objective, and the other extreme is interrelated weight and length objectives. A good compromise facilitates a low number of struts for efficiency with a large bottom radius (footprint) but within an appropriate length to minimise buckling and ease transport (approximately 4.5m). To answer the research question, the trade-offs include unnecessarily large footprint which might not be suitable in every emergency situation and the ability to find the appropriate length of bamboo poles for the compression members.\u003c/p\u003e \u003cp\u003eFrom the above-mentioned study and reflections, the future agenda focuses on the development of the thermally sound shelter skin made of a widely available sheeting, further improvements in the suitable hardware and tools (rope stretchability tests of different kinds of ropes, lashing techniques, fixed and non-fixed joints to ease the speed of assembly, etc), optimising the tensioning system and refining different solutions for the two main groups of shelters (one to two-person and three to six-person).\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eFirst manuscript: the first author developed the Abstract, Introduction, Relevant literature, Rationale and Conceptual Design of Bamboo Tensegrity Structure sections; the second author ran the multi-objective optimisations; the first and second authors both built, dismantled and re-built the prototype; the first author wrote the Research Methodology section, the second author wrote the Results section; both first and second authors wrote Discussion section; and lastly the second author wrote the Conclusions section.Second manuscript (revision): the first and second authors co-edited the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eAbdelmohsen, S., Massoud, P. \u0026amp; Elshafei, A. 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Joints in bamboo construction. \u003cem\u003eNonconventional and Vernacular Construction Materials.\u003c/em\u003e Elsevier.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Bamboo Structures, Tensegrity, Disaster Relief Shelters, Computational Simulation and Multi-objective Optimisation","lastPublishedDoi":"10.21203/rs.3.rs-5739117/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5739117/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis paper seeks to optimise a system of immediate relief shelters which are quick to deploy, easily assembled by unskilled workers and utilise locally sourced and sustainable materials. It addresses concerns such as time-consuming tent delivery as the first response during emergencies and cost-effectiveness and exploits the self-erecting affordances of tensegrity structures. The research adopts a multi-phase methodology, an iterative multicriteria simulation and prototyping optimisation. The three stages are: (1) computational simulation followed by multi-objective optimisation, (2) full-scale prototyping, and (3) a second round of multi-objective optimisation informed by prototype evaluations. The discussions around the self-build bamboo tensegrity sleeping structures are focused only on the compression and tensional elements (without skin or fa\u0026ccedil;ade, which will be the focus of a subsequent study). Five design parameters are investigated: the number of bamboo struts, overall height, degree of rotation, and radius of the top and bottom sections. By optimising these parameters, three performance criteria are considered to evaluate spatial needs and portability: the possible number of occupants, the total weight, and the length of each bamboo strut. The study finds that after optimisation, these shelters are best suited to occupancy rates of one to five people, however, three people are required to erect the structures and carry longer bamboo culms so this must be factored into any potential deployment scenario.\u003c/p\u003e","manuscriptTitle":"Multi-objective Optimisation of Bamboo Tensegrity Structure for Post-disaster Immediate Relief","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-03 14:23:57","doi":"10.21203/rs.3.rs-5739117/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0b340521-de6d-4081-bef3-faa1180d77b4","owner":[],"postedDate":"April 3rd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-06-02T15:59:26+00:00","versionOfRecord":{"articleIdentity":"rs-5739117","link":"https://doi.org/10.1186/s40410-025-00263-x","journal":{"identity":"city-territory-and-architecture","isVorOnly":false,"title":"City, Territory and Architecture"},"publishedOn":"2025-05-29 15:57:05","publishedOnDateReadable":"May 29th, 2025"},"versionCreatedAt":"2025-04-03 14:23:57","video":"","vorDoi":"10.1186/s40410-025-00263-x","vorDoiUrl":"https://doi.org/10.1186/s40410-025-00263-x","workflowStages":[]},"version":"v1","identity":"rs-5739117","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5739117","identity":"rs-5739117","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}