Assessment of Multi-Perspective and Multi-Sensor Data for Urban Strata Mapping

Abstract Many countries have seen a significant increase in the number of high-rise and multi-story buildings with strata units with the shrinking availability of horizontal land space in urban areas. Most existing cadastres record tenure and associated information in a two-dimensional format, and therefore will need to be upgraded to 3D cadastres to facilitate the recording of title information for these strata units. The geospatial aspects of implementing a 3D cadastre require cost-effective, rapid, accessible, non-labor intensive, and accurate means by which complete data may be collected to model strata units. Existing data sources such as Building Information Models (BIMs) have been used to delineate these units. However, BIMs are not easily accessible in developing countries. There is no single spatial data source that can easily fulfill all the criteria of a 3D data source for mapping urban strata boundaries. However, leveraging multi-perspective and multi-sensor data can theoretically serve this purpose. In this paper, we report on research conducted to demonstrate the feasibility of using low cost and accessible cell phone data, integrated with higher accuracy terrestrial laser scan data, and drone aerial imagery to produce a multi-perspective 3D data source. It was found that the integration of these data sets as a 3D data source, resulted in absolute accuracies within centimetres and decimetres in the horizontal plane and within millimetres in the vertical plane. Overall, the integration of these three sources of data may be appropriate in meeting the needs for a low-cost source of 3D data.