A COMPARISON STUDY OF LOW-COST PERSONAL LASER SCANNING SYSTEMS FOR FOREST PLOT-LEVEL INVENTORIES

Forest resource is an essential part of the environment, and can be used for carbon sink, soil conservation, windbreak and sand fixation, which is of great significance to maintaining the balance of ecologic and sustainable city development. Due to the complexity of wildwood, the approach of traditional forest inventory is difficult, low-efficiency, and labour-intensive. Thus, a handheld personal laser scanning (PLShh) system is proposed in this paper. To solve the limitation of low-cost LiDAR's FoV, two LiDAR scanners (Ouster OS-1-128 and Hesai PandarXT-32) are integrated in our PLShh system. The enhancement of our PLShh have be demonstrated by the experiments in field forest plots. The comparison of trajectory and the comparison of point cloud have been conducted extensively. Experiment results show that the trajectory estimated by two scanners (Ouster and Hesai) has a strong consistency with using one scanner (Ouster), with standard deviation at sub-centimetres level. And the trajectory deviation between two scanners and UWB is similar to 15cm, which is consistent with the inherent positioning accuracy of UWB sensors. In addition, the point cloud data obtained by two scanners or one scanner have been quantitatively evaluated by the TLS (Leica RTC 360) muti-scan. The difference between tree height extracted from two scanners and TLS data was small, even at sub-meter level only. But the tree height extracted from one scanner is lower similar to 8m in comparison with TLS data, because of the limitation of vertical FoV. Therefore, the great potential of our PLShh system with two scanners has been shown in the application of forest inventory.