【摘要】 与关节臂坐标测量机一样,自驱动关节臂坐标测量机存在诸多结构参数误差影响其测量精度。为了提高自驱动关节臂坐标测量机的测量精度,文章建立以激光跟踪仪测量距离为基准的标定系统,并对该系统的标定算法进行研究。根据Denavit-Hartenberg(D-H)模型,建立自驱动关节臂坐标测量机运动学模型;用激光跟踪仪标定自驱动关节臂坐标测量机测量距离的误差,建立距离误差模型,设计基于最小二乘迭代Levenberg-Marquardt(LM)的标定算法。实验结果表明,经LM算法标定且对自驱动关节臂坐标测量机的结构参数补偿后,在标定空间内测量20组距离,最大距离误差绝对值从13.895 0 mm减小到0.300 4 mm,测量误差减小了近97.8%。更多还原

【Abstract】 Like the articulated arm coordinate measuring machine(AACMM), the self-driven AACMM also has many structural parameters errors that affect its measurement accuracy. In order to improve the measurement accuracy of the self-driven AACMM, a calibration system based on the distance measured by the laser tracker was built, and the calibration algorithm of the system was studied. According to the Denavit-Hartenberg(D-H) model, the kinematics model of the self-driven AACMM was established. The laser tracker was used to calibrate the distance measurement errors of the self-driven AACMM, the distance errors model was established, and the calibration algorithm based on Levenberg-Marquardt(LM) was designed. The experimental results show that after calibration by LM algorithm and compensation for the structural parameters of the self-driven AACMM, 20 sets of distances were measured in the calibration space, the absolute value of the maximum distance error measured was reduced from 13.895 0 mm to 0.300 4 mm, and the measurement error of the self-driven AACMM was reduced by nearly 97.8%.更多还原