A method of automatic extraction and modeling of indoor spatial data based on CAD

Aiming at the problems of closed indoor environment and complex spatial constraints, which lead to the high cost and time-consuming of indoor information collection using traditional surveying and mapping technology, a method for automatic extraction and modeling of indoor spatial data based on CAD is proposed. Use the existing DXF format indoor architectural drawings to extract spatial information. According to different characteristics of DXF indoor architectural components, two methods based on rules and spatial relationships are used to extract each spatial feature. Then, the H3 grid structure is used to grid the extracted spatial features to generate grid sets; finally, using the anchor points of DXF primitives, the grid sets of spatial features are matched with text primitives to obtain subject words or keyword information and establish indoor data in the form of database tables. The experimental results show that this method reduces the grid model modeling workload to a great extent and improves the map update rate at the same time.