Real-time Compensation Strategy of Mobile Robot Positioning Accuracy

doi:10.3901/JME.2022.14.044

Abstract

Abstract: As an effective technical way to solve the in-situ processing of large and complex components, the positioning accuracy of mobile robots directly affect the quality and efficiency of product processing. For this reason, a real-time compensation method for positioning accuracy is proposed based on the control architecture of an industrial robot driven by a CNC system. The sampling point selection of the robot joint space is realized by Latin hypercube sampling, and the spatial uniformity of the sampling point set is optimized by calculating the deviation of the sampling point set; A multivariate nonlinear mapping model of robot joint space and end position error is established. The structure of the model is simplified by calculating the regression coefficient, and the prediction accuracy of the model is evaluated based on the set of sampling points; Based on the commercial CNC system, the real-time compensation of the robot's TCP point accuracy is realized, and the position error of the robot's TCP point in different pose is verified. The real-time compensation and stability are verified by the accuracy of the linear interpolation trajectory. The experimental results show that the comprehensive error of maximum positioning accuracy of industrial robot driven by CNC system is reduced by 79.6% from 1.635 mm before compensation to 0.334 mm after compensation. The trajectory accuracy before and after compensation does not change significantly, which proves the effectiveness and correctness of the above method, and lays a foundation for the application and promotion of mobile robot.

Key words: mobile robot, accuracy improvement, sampling point optimization, real-time compensation, error mapping model

CLC Number:

TP242

YANG Jizhi, YUE Yi, ZHANG Jiabo, ZHOU Yinghao, ZHAO Changxi, CHEN Qintao. Real-time Compensation Strategy of Mobile Robot Positioning Accuracy[J]. Journal of Mechanical Engineering, 2022, 58(14): 44-53.

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