Research On Calibration Algorithm Of Parallel Robot

Accuracy is one of the important indicators to measure the performance of parallel robots.How to complete the calibration and compensation of parallel robot errors is a core issue in the field of parallel robots.In this paper,the six-degree-of-freedom parallel robot platform independently designed by the research group is taken as the research object to analyze and calibrate the error factors.The inverse kinematics solution of the robot platform is completed through coordinate transformation,and the multi-dimensional descent simplex method is combined with the inverse kinematics solution to complete the forward kinematics solution of the robot platform.Analyze the error source of the robot platform and determine the calibration parameters.On this basis,the posture error analysis models based on inverse kinematics and forward kinematics were established respectively,and then the error analysis model based on forward kinematics was used to perform error analysis to determine the main error factors affecting the posture accuracy of the upper platform.Secondly,in view of the shortcomings of traditional calibration methods,a calibration algorithm based on forward kinematics and a calibration algorithm based on inverse kinematics are proposed to convert the error calibration problem of the robot platform into a continuous optimization problem,and the descent simplex method is used to solve it.In addition,the error calibration when the relative position of the measuring instrument is not fixed is analyzed,and the effectiveness of the algorithm is verified in the simulation environment.Finally,the binocular camera is used to actually measure the posture of the platform on the robot,and the error is calibrated after the measurement data is processed.After the calibration is completed,the posture of the upper platform is measured again.According to the accuracy evaluation index,it is found that the accuracy of the posture of the platform on the robot is significantly improved,thus The effectiveness of the calibration method adopted in this paper is verified.