结构光测量系统误差分析

Error Analysis in Structured Light System

本文针对交比不变原理的结构光光平面标定方法,利用泰勒展开和矩阵扰动原理分别对系统的测量误差和光平面标定误差进行分析,提出了结构光测量系统的误差传递模型。并给出了一个实验特例的精度要求,即满足在1 000 mm的测量距离上获得±0.5 mm以内的测量精度情况下,各标定参数所需满足的精度要求,以及标定样本的精度要求。对误差传递模型所得出的标定参数的精度要求进行实测实验验证,得到测量数据的均方根误差为0.333 4 mm,满足理论上的精度要求。该实验结果证明了本文所述的误差分析可以有效地对结构光系统误差进行定量分析。

The error propagation model in structured light system was presented. Based on Taylor decomposition and the principal of matrix turbulence, the measuring error of structured light and error from light-plane calibration were analyzed, in which cross-ratio invariant was used in calibration of structured light system. The demands of precision in the specific example were presented, which were ones of calibration parameters and samples under the conditions of acquisition of 4-0.5 mm precision in the measuring range of 1 000 mm. According to the error propagation, experiment was made by using the precision of calibration sanaples. The measuring results are that the value of Root Mean Square （RMS） is 0.333 4 mm, which meets the requirements of theoretical precision. The experimental results validate that those error analyses would provide the principle basis for wider application of structured light system.