Delta并联机构正向运动学标定方法研究

Forward Kinematic Calibration of Delta Parallel Mechanism

为提高Delta操纵机构位置测量精度,提出了一种离线参数辨识标定方法。根据机构结构和运动学模型,对影响操作端精度的各项误差源进行分析,建立了含误差参数的正向运动学模型;通过分析各项误差源对操作端位置误差的影响,发现12项装配误差对操作端的位置影响较大,提出对运动学模型中的装配误差进行参数辨析,以此修正正向运动学模型;试验结果表明,标定后的Delta机构提高了位置重复测量精度。

A calibration method was presented by off-line parameters identification in order to enhance the position measuring accuracy of the Delta mechanism. Based on structure and kinematic model of mechanism, the error sources influenced accuracy of operation end were analyzed. A forward kinematic model contained errors sources was built. By analyzing the effect of error sources on position error of operation end, twelve assembling errors that made more effect on position of operation end were presented and solved, and the forward kinematic model was calibrated. The experiment results showed that the calibrated Delta mechanism improved the measurement accuracy of position.