Parameter identification algorithm of kinematic calibration in parallel manipulators

In this article, a parameter identification algorithm of kinematic calibration in parallel manipulators is proposed and compared with two conventional algorithms. By analyzing the identification matrix with singular value decomposition, the mathematical properties of the identification algorithms are investigated, and a novel algorithm based on singular value decomposition is proposed. Two parallel manipulators, which have been successfully applied in practice, are introduced and their system models are established, respectively. In order to show the reliability and feature of algorithms, the calibration simulations of these two parallel manipulators are performed with different parameter identification algorithms. Since these parallel manipulators are needed to guarantee 5-degree-of-freedom motion accuracy at least, the parameter identification simulations are performed based on both 6-degree-of-freedom measurement and 5-degree-of-freedom measurement. Compared with two conventional algorithms, the novel algorithm has the best solution in all simulation situations. The investigation in this article is very helpful for the parameter identification of kinematic calibration in parallel manipulators.