Complete kinematic calibration of a 6-RRRPRR parallel kinematic machine based on the optimal measurement configurations. (January 2020)

• Record Type: Journal Article
• Authors: Han, Chunyang; Yu, Yang; Xu, Zhenbang; Wang, Xiaoming; Yu, Peng; Zhou, Xiaoqin
• Is Part Of: Proceedings of the Institution of Mechanical Engineers. Volume 234:Number 1(2020)
• Page Start: 121
• Page End: 136
• Publication Date: 2020-01
• Subjects: Parallel kinematic machine -- complete error model -- observability index -- optimal measurement configurations -- calibration experiment; Mechanical engineering -- Periodicals; 621.05
• DOI: 10.1177/0954406219869985
• Languages: English
• ISSNs: 0954-4062

Abstract

This paper presents a kinematic calibration of a 6-RRRPRR parallel kinematic mechanism with offset RR-joints that would be applied in space positioning field. In order to ensure highly accurate and highly effective calibration process, the complete error model, which contains offset universal joint errors, is established by differentiating inverse kinematic model. A calibration simulation comparison with non-complete error model shows that offset universal joint errors are crucial to improve the calibration accuracy. Using the error model, an optimal calibration configuration selection algorithm is developed to determine the least number of measurement configurations as well as the optimal selection of these configurations from the feasible configuration set. To verify the effectiveness of kinematic calibration, a simulation and experiment were performed. The results show that the developed approach can effectively improve accuracy of a parallel kinematic mechanism with relatively low number of calibration configurations.