Simulation on impact of random attitude measurement errors on point cloud and 3D image of ALS

The influence of random attitude measurement errors of the GPS/INS integrated system on the laser point cloud and the three-dimensional (3D) surface image reconstructed by the airborne laser scanner was studied. The mapping relationship between the attitude measurement errors and the positioning errors of the laser footprints was derived. By numerical simulation, three common terrains, i.e. a planar, a rectangular, and a hemisphere terrain, were simulated, and the impacts of the random attitude measurement errors on the laser point clouds and the reconstructed 3D surface images of the three terrains were analyzed, respectively. Simulation results show that the random attitude measurement errors decrease the positioning accuracy of the laser point clouds, further directly deteriorating the 3D surface image. The greater the random attitude measurement errors are, the greater the caused 3D imaging distortion.