基于几何参数标定的串联机器人精度提升

Accuracy Improvement of Serial Robot Based on Geometric Parameters Calibration

为了提升串联机器人绝对定位精度,提出了基于零参考模型(ZRM)的机器人几何参数标定方法。建立了包含方向矢量和连接矢量的机器人零参考模型;针对模型特点,利用改进遗传算法(IGA)优化求解零位方向分量和位置方向分量,给出了用IGA标定几何参数目标函数值计算方法及求解几何参数误差的具体步骤。通过对ER10L-C10工业机器人不同测点下仿真标定及实测研究结果表明:IGA方法能够快速对机器人ZRM的几何参数实现标定,当标定点设定为50个左右时,标定后的机器人在测试点的精度提升泛化能力较好,对ER10L-C10机器人在整个工作空间内实测标定其末端绝对定位精度提升约90%,该方法适于在有高定位精度要求的串联机器人中推广应用。

In order to enhance the absolute positioning accuracy of the robot,a calibration method based on zero reference model(ZRM)is proposed.ZRM including direction and connection vectors is founded.According to the features of ZRM,improved genetic algorithm(IGA)is used to search the solution of the direction and position components of zero position vector.The objective function computation methods and the detailed steps of calibrating geometric parameters of ZRM based on IGA are given.Finally,by carrying out the simulation and real measurement research for ER10L-C10 industrial robot,the results show that the geometric parameters of ZRM can be quickly calibrated by IGA.When the calibration point is set at about 50,the accuracy improvement of the test points after calibration has good generalization ability and in the whole workspace the positioning accuracy of the ER10L-C10 end-effector is improved about 90%.This method is suitable to be applied in serial robot calibration with high positioning accuracy requirements.