Abstract: To solve the problems of low efficiency and poor accuracy of manual measurement in the process of distortion correction in laser galvanometer processing,a distortion correction and precision measurement method assisted by machine vision was proposed.In this method,the theoretical distortion model was established as result of error analysis.The combination of spiral-filling-circle marking and the minimum circumcircle detection were used to obtain the error description of the galvanometer system,and the error was compensated online with curve fitting algorithm or linear interpolation algorithm.Moreover,the standard circle array of error measurement was marked for accuracy calibration.Experiment results showed that the proposed method could eliminate 86% of the graphic distortion with an average relative error of 7×10-4,which improved not only accuracy but also efficiency of the correction.

Key words: laser galvanometer processing, graphic distortion, calibration accuracy, machine vision

摘要： 为了解决激光振镜加工畸变校正过程中人工测量效率低、精度差的问题,提出一种视觉辅助的畸变校正和精度测量方法。该方法分析了误差来源,建立了畸变数学模型,采用螺旋式填充圆标刻配合最小包络圆检测获取振镜系统误差特征描述,用曲线拟合或线性插补算法补偿误差,最后采用误差标准测量点阵进行精度标定。实验结果表明,该方法可以消除86%图形畸变,平均相对误差为7×10-4,提升了校正精度和校正效率。

关键词: 激光振镜加工, 图形畸变, 校正精度, 机器视觉