Abstract
Indoor maps lay the foundation for most indoor location-based services (LBS). Building Information Modeling (BIM) data contains multiple dimensional computer-aided design information. Some studies have utilized BIM data to automatically extract 3D indoor maps. A complete 3D indoor map consists of both floor-level maps and cross-floor paths. Currently, the floor-level indoor maps are mainly either grid-based maps or topological maps, and the cross-floor path generation schemes are not adaptive to building elements with irregular 3D shapes. To address these issues, this study proposes a novel scheme to extract an accurate 3D indoor map with any shape using BIM data. Firstly, this study extracts grid-based maps from BIM data and generates the topological maps directly through the grid-based maps using image thinning. A novel hybrid indoor map, termed Grid-Topological map, is then formed by the grid-based maps and topological maps jointly. Secondly, this study obtains the cross-floor paths from cross-floor building elements by a four-step process, namely X-Z projection, boundary extraction, X-Z topological path generation, and path-BIM intersection. Finally, experiments on eight typical types of cross-floor building elements and three multi-floor real-world buildings were conducted to prove the effectiveness of the proposed scheme, the average accuracy rates of the evaluated paths are higher than 88%. This study will advance the 3D indoor maps generation and inspire the application of indoor maps in indoor LBS, indoor robots, and 3D geographic information systems.
Highlights
Indoor maps are the fundamental elements for indoor location-based services (LBS) [1], such as pathfinding in hospitals [2], escape path planning during emergency situations [3,4], and passenger transfer in transport stations [5]
Most individuals have been enjoying the advantages of outdoor LBS such as Google map based on comprehensive outdoor map networks [7], but indoor maps have not been fully developed [8]
Most studies failed to interpret how to generate a complete 3D indoor map, which consists of both floor-level indoor maps and cross-floor indoor maps
Summary
Indoor maps are the fundamental elements for indoor location-based services (LBS) [1], such as pathfinding in hospitals [2], escape path planning during emergency situations [3,4], and passenger transfer in transport stations [5]. Many efforts have been made in the extraction of both grid-based indoor maps and topological indoor maps using BIM data, most studies have focused on only one of these types. Since the floor-level indoor maps generation using BIM data has been systematically investigated in our previous work [2], this study mainly focuses on cross-floor indoor path generation and proposes a novel cross-floor 3D topological map using a four-step process, which supports the path generation for cross-floor building elements with any 3D shapes. The main contribution of this study is to develop a scheme to extract crossfloor paths for various irregular connecting elements between two different floors and generating a complete 3D indoor map by combining this cross-floor map with a hybrid
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have