3D Visualization of Articulated Mechanisms: Coupling Their Dynamic and Virtual Models on Example of Driving of the Omnidirectional Mobile Robot

This paper proposes novel approach to 3D virtual modeling of articulated mechanisms. It follows widespread use of XML for various applications and defines a version of XML specially designed for description of 3D geometric models of articulated bodies. It was shown how the 3D geometric model of a mechanism can be gradually developed using suitable defined elements and stored in corresponding XML file. The developed XML model is processed and using powerful VTK (Visualization Toolkit) library the corresponding virtual model is built and shown on the computer screen. To drive the virtual model the dynamical model of the mechanism is developed using Bond Graph modelling techniques. The models, 3D virtual geometric and dynamic, are created using the corresponding software packages: BonSim3D Visual and BondSim. The models are interconnected by a two-way named pipe. During the simulation of dynamical model, the parameters necessary to drive the virtual model (e.g., the joint displacements) are collected and sent to the virtual model over the pipe. When the virtual model receives a package the computer screen is updated showing the new state of the mechanism. The approach was demonstrated on example of a holonomic omnidirectional mobile robot.