3-PRS并联机构误差运动学分析及辨识

Kinematical error analysis and identification of a 3-PRS parallel mechanism

少自由度并联机构是并联机构的重要分支之一。和全自由度并联机构相比,由于受到运动约束,因此在运动学标定的过程中需要对此加以分析,结合运动学方程组得到完整的辨识矩阵。该文基于3-PRS少自由度并联机构,首先对少自由度并联机构运动学标定进行误差建模,通过理论分析得到最简化的误差模型,并使用遗传算法进行了测量位姿选择,其次通过仿真计算验证了分析的正确性和有效性,最后结合仿真结果提出一种误差辨识能力分析方法。

Limited-DoF（degree of freedom） parallel mechanism is one of the important branches in a parallel mechanism.Compared with full-DoF parallel mechanism,limited-DoF parallel mechanism,with motion constraints,needs to be analyzed in the process of kinematical calibration to obtain complete identification matrix combined with kinematical equation set.In this paper,a kinematical error model was established and a minimal error model was derived based on 3-PRS limited-DoF parallel mechanism.Measuring poses were optimized using the genetic algorithm.Simulations show the correctness and effectiveness of the analysis,with a scheme of error identifiability analysis being developed.