三维激光球杆仪的系统误差分析与补偿

Error Analysis and Compensation of 3D Laser Ball Bar

三维激光球杆仪是自研发的一种被动式激光跟踪仪,为了提高其测量精度,该文系统地分析了其主要误差源及补偿方法。首先,通过误差源分析,基于多体系统误差建模理论对仪器进行精度建模;其次,针对误差补偿模型,提出了简单有效的模型参数测量方法,即多齿分度台和光电自准直仪标定二维转台两测角误差,正倒镜法测量两旋转轴的不相交度,精密三轴机床测量轴系不垂直度误差;最后,完成精度补偿验证。实验结果表明,在有效测量范围内,补偿后的垂直度误差从120μm减小到28μm,X轴定位误差从20μm减小到8μm,Z轴定位误差从60μm减小到25μm。研究表明该补偿方法在不改变硬件结构的基础上能有效提高仪器的精度。

The 3D laser ball bar independently developed is a passive laser tracker and in order to improve its measurement accuracy,the main errors sources and compensation method were systematically analyzed.First,based on the analysis of error sources,the multi-body system error modeling method was used to establish the error compensation model.Then,a series of calibration methods for model parameters were proposed,such as using multi-tooth indexing table and autocollimator to calibrate the angular error of two rotary stages,using two-face test to measure the offset of the two rotary shaft directly,and using precision three-axis machine tool to measure the shafting non-perpendicularity.Finally,accuracy compensation verification experiments were conducted.Experiment results indicate that the verticality error is reduced from 120μm to 28μm,the position error of X axis is reduced from 20μm to 8μm and the position error of Z axis is reduced from 60μm to 25μm within the effective measurement range after compensation.The compensation method can effectively improve the measurement accuracy without changing the hardware structure of the system.