Research on Hand-eye Calibration Method of Linear Structured Light Vision Guided Robot System Based on M-type Standard Block
Aiming at the hand-eye calibration problem of the linear structured light sensor-guided robot system,a method using M-type standard block as the calibration object is proposed.Based on the constraints of two parallel ridges of the M-type calibrator as the constraints,the models such as the hand-eye relationship,robot kinematics,and the error of two linear pose parameters are estab-lished.Firstly,the initial value of the hand-eye relationship is solved based on the fixed-point constraint,on this basis,and the initial value of the linear pose parameter is solved.Then,the error parameters are solved by the least square method and compensated into the model,and the iterations are continuously performed until the calculated error parameters are less than the threshold.Finally,the final hand-eye relationship and kinematic error parameters of the robot are obtained.In order to verify the effectiveness of the calibra-tion method,calculating the root mean square of the distance from a point to a plane is used as a measured object,and the linear struc-tured light robot system is used to measure the plane and obtain a plane point cloud;The least-squares plane is fitted,and the RMS of the distance from the point to the plane is calculated as the evaluation basis.The two methods of M-type standard block and standard ball are experimentally compared,respectively.The results show that compared with the standard sphere method,the RMSE of the M-type standard block method is reduced from 0.152 mm to 0.080 mm,and the standard deviation of the RMSE is reduced from 0.043 mm to 0.005 mm.The accuracy and stability of the calibration results are significantly improved.
万方数据
维普
