Subway Tunnel Intrusion Detection Method Based on Lidar

The subway tunnel clearance is directly related to the safe operation of trains and the maintenance of facilities. However, the low light of the tunnel causes the low accuracy and short inspection distance based on the video inspection method, which hinders the development of tunnel inspection. Aiming at the problems, this paper proposes an intrusion detection method for subway tunnel based on lidar, which uses lidar to scan long-distance subway tunnel scenes to obtain tunnel point cloud. Firstly, the tunnel section point cloud is obtained by preprocessing. Secondly, a three-dimensional tunnel bounding region is constructed by extracting and projecting the optimal bounding box. Finally, an adaptive matching mechanism between the bounding region and the tunnel point cloud is constructed to realize the judgment of tunnel intrusion. The algorithm proposed in this paper achieves 100% detection accuracy within 100 m of the tunnel, improves the detection accuracy of tunnel intrusion detection, and promotes the development of tunnel inspection.