Volume Measurement Of Live Standing Tree Based On3D Laser Scanning Technology

The total volume of the existing variety of living trees were known as the forest volume in a certain forest area, it is an important indicator to measure the forestry management effectiveness of a national or regional. The existing of measurement methods obtain diameter at breast height and tree height and cross-sectional area at first, and finally substituted into empirical formula, the precisely of result is a little lower. The application of3D laser scanning technology to estimate the volume of living trees is one of the hot issues of the current forestry research.Because of the complexity of trees shape, the shelter between foliage and trees and other objective factors, so that the study of processing point cloud data become a hot research and difficult. This paper present a method to calculate volume of living tree based on three dimension technology, explore a volume measurement method of living tree based on laser scanning technology, lay a technique foundation to estimation the volume of forest timber.The main works were listed as follows:1. The collection and pre-processing of point cloud data. Firstly, this paper uses the FARO LS80terrestrial3D laser scanner to collect live standing trees point cloud data, and then registration and de-noising. At last, point cloud data of live standing trees has been simplified with a non-uniform method based on octree and normal vector.2. The3D model reconstruction of tree trunk. Because of the Crust algorithm could generate the number of poles may reach1to3times as the original amount of data, so that the efficiency of the triangulation will be reduced. This paper presents a new method to construct the grid model of trunk, and extracts Crust triangular diagram by the changes of normal vector, in addition, reduces the time of Delaunay triangulation.3. The volume calculation of live standing tree trunk. This paper presents an improved projection algorithm to calculate the volume of the trunk mesh model, we determine an intersection collection of triangle by using the bounding box, this method narrow the scope of testing, secondly, according to the normal vector direction of triangular, we divide triangular projection volume into positive and negative, compared to the volume by the national standard GB4814-84measurement of forest inventory, the deviation is4.1%of mulberry tree model calculation by using our method.