摘要
针对目前立木胸径算法性能对比中以树干作为测量目标而无法精确评估这一问题,使用激光扫描雷达,以5种管径的PVC管作为测量目标,应用目前常用的两种几何法(切线法、弧长法)与拟合法(Taubin),结合对应的4种角度补偿算法计算目标直径,分析各种算法误差及适用范围,对各种算法性能进行评价。结果表明,Taubin算法精度最高,考虑所有样本后,平均绝对误差为4.89%,其中测量距离为3~6 m时精度最高,平均绝对误差为3.62%。管径小于200 mm,测量距离小于2 m时,所有计算方法的误差均相对较高,其中Taubin法的平均绝对误差为10.59%,优化的弧长法与切线法的平均绝对误差分别为14.03%和13.47%。当测量距离大于2 m时,算法精度大幅度提升,Taubin算法的平均绝对误差降到6%以下。实验表明,Taubin算法在所有计算方法中精度与稳定性最高,最具有工程应用价值。
Study on tree DBH algorithm based on two-dimensional laser has engineering significance to forestry surveying. In order to solve the problem that the performance of algorithm can not be evaluated effectively when the trunkwas taken as the measurement target. Five kinds of PVC tubes were scanned with laser scanning radar. Two kinds of geometric methods（ tangent method and arc length method） and fitting method（ Taubin）, which are commonly used at present, corresponding four optimization algorithms were used to calculate diameter. The error and suitable range of the algorithm were analyzed and the performance of various algorithms was assessed. Results showed that Taubin algorithm had the highest precision,considering all samples the mean absolute error was 4. 89%. It had the highest precision when measuring distance rang from 3 m to 6 m in which the mean absolute error was 3. 62%.The errors of all calculation methods were relatively high when the pipe diameter was less than 200 mm and measuring distance was less than 2 m. The mean absolute error of Taubin method was 10. 59%,the mean absolute error of optimized arc length method and tangent method were 14. 03% and 13. 47%,respectively. The accuracies of measured values of radius were greatly improved when measuring distance was further than 2 m. The mean absolute error of the Taubin algorithm was reduced below 6%.Experimental results showed that the Taubin algorithm had the highest accuracy and stability in all methods,which was valuable for engineering applications.
作者
孙浩
刘晋浩
黄青青
赵可
SUN Hao;LIU Jinhao;HUANG Qingqing;ZHAO Ke(School of Technology，Beijing Forestry University，Beijing 100083，China)
出处
《农业机械学报》
CSCD
北大核心
2017年第8期186-191,共6页
Transactions of the Chinese Society for Agricultural Machinery
基金
林业公益性行业科研专项经费项目(201504508)
"十二五"国家科技支撑计划项目(2015BAD07B00)
关键词
立木胸径
二维激光扫描
几何法
性能分析
DBH of standing tree
two dimensional laser scanning
geometry algorithm
performance analysis
