Study on Wind-eroded Concave Surface Morphology Based on Laser Radar and Color Space Encoding

Abstract This article takes a test area in the eastern edge of Greenbulongtan, Barunbireli Town, Alxa Left Banner, Alxa League, Inner Mongolia Autonomous Region, where a polylactic acid fiber (PLA) sand barrier is installed, as the research object. By using the three-dimensional scanning technology and software such as Sketch Up with the portable device iPhone12 Pro Max equipped with a LiDAR, the boundary length, erosion depth, erosion coefficient, and erosion intensity of the concave surface of the sand barrier in the test area were measured through the method of model size measurement. In addition, the model size measurement method and the novel RGB numerical simulation algorithm proposed in this paper were mutually corroborated in terms of the accumulation rate of the concave surface. The experiment shows that the erosion coefficient of the PLA wind erosion concave surface with a size of 1.5 m×1.5 m in the test area is about 1.34, the accumulation intensity is about 0.8 ml/ cm 2, and the erosion intensity is about 1.2 ml/ cm 2. The overall erosion amount in the test area is greater than the accumulation amount, and the stability of the 1.5 m×1.5 m PLA sand barrier in the experimental stage is poor. Exploring the relationship between the specific RGB values and eleva-tion is the highlight of this article. The novel RGB numerical simulation algorithm proposed in this paper calculates the erosion rate, which fits with the erosion rate obtained by measuring the three-dimensional model size data, with a fitting degree of more than 98%. This proves that using LiDAR three-dimensional modeling to study wind erosion concave surfaces is feasible, and the RGB numerical simulation algorithm is simple and effective in quickly and efficiently processing complex concave terrain.