Research On Optimal Workspace And Error Compensation Of Robot

Low absolute positioning accuracy of robots is a technical problem that is widely used in the industrial field.In order to improve the absolute positioning accuracy of robots,this thesis uses the spiral theory to establish a robot kinematics model,screens out the optimal working space of the robot,and refers to the distance error design parameter recognition algorithm.The kinematics model of the robot is corrected to improve the absolute positioning accuracy of the robot.The specific research in this thesis is mainly divided into the following points:(1)The generalized kinematics model of the robot is established based on the spiral theory,and verified in the selected Aubo Robot I3.The mathematical basic principle of the spiral theory is introduced,and the positive kinematics model of Aubo Robot I3 based on this theory is established under the tool coordinate system.The joint parameters of the robot are extracted,and the panda subproblem method is used to solve the problem of robot inverse motion.The Monte Carlo method is used to visualization the robot’s working space,which is used for the selection of the optimal working space and the robot error measurement and compensation.Establish a model foundation.(2)The optimal working space of the robot is screened out.The Jacobi matrix under the spiral theory is deduced,the condition number of the Jacobi matrix is solved and analyzed,and the maneuverability of the robot is quantified by the motion performance index.The overall and optimal working space of Aubo Robot I3 are visualized by the Monte Carlo method.An experimental verification platform is built,and the robot end position error information is collected using the API laser tracker.The results show that the absolute positioning accuracy in the optimal working space is higher than the overall working space,which verifies the reliability of the optimal working space.(3)The robot accuracy calibration algorithm is constructed.The geometric distance error theory is introduced,which is organically combined with the spiral theory,the Aubo Robot I3 distance error model is established,the robot accuracy calibration algorithm is constructed,the robot joint error compensation algorithm is simplified,and the calibration efficiency is improved.(4)An error compensation system with the tool coordinate system as a reference is established.An experimental verification platform is built,and the selection flexibility of the laser tracker for the measurement coordinate system is used to establish the measurement coordinate system on the tool coordinate system of the robot,which avoids the coordinate conversion error during data processing and improves the reliability of the calibration algorithm.In this thesis,the absolute positioning accuracy of the robot is improved by screening the optimal working space of the robot and correcting the kinematics model of the robot.After the measurement data analysis of the API laser tracker,the accuracy in the optimal working space of the robot is higher than that of the overall working space,from 5.232 mm down to 3.532 mm,and the accuracy is increased by 32.49%.The corrected distance error is significantly lower than the uncorrected robot model,and its average distance error is reduced from 3.5 mm to 1.592 mm,and the absolute positioning accuracy of the robot is increased by 54.51%.