An airborne laser SLAM method integrating LiDAR/IMU/GNSS

Abstract

The airborne laser scanning (ALS) system is an efficient 3D spatial data acquisition system that plays a key role in complex environmental mapping. Traditional ALS systems primarily depend on GNSS/INS integrated navigation to compute high-precision poses, with LiDAR used only for measuring accurate distances from the sensor to ground targets, without contributing to pose estimation. In GNSS-denied or degraded environments, the pose error of pure inertial dead reckoning diverges over time, leading to reduced mapping accuracy or even complete failure. Simultaneous Localization and Mapping (SLAM) is an autonomous navigation and mapping technology that provides a promising solution to this problem. In the absence of GNSS data, it estimates the pose by matching laser point clouds with a local map, and then fuses the result with IMU data to maintain pose accuracy. Taking the airborne mode of the L3-Pro system as an example, this paper presents the principles of SLAM and its application in airborne laser scanning. Experimental results from multiple scenarios demonstrate that the proposed system achieves centimeter-level accuracy.