中文摘要：

研究了一种4自由度—虎克铰—移动副—球铰/转动副—移动副—虎克铰冗余并联机构的运动学性能评价指标和优化设计,建立了该并联机构的雅可比矩阵,得到了该机构的3个不同的运动学性能评价指标,即条件数、最小奇异值和可操作性,在此基础上,定义了评价不同位形下运动学综合性能的全局灵巧度系数指标,并分别研究了不同性能评价指标在并联机构工作空间内的分布规律。最后,基于全局灵巧度指标,利用遗传算法对冗余驱动并联机构的结构参数进行了优化设计。为该冗余并联机构的结构设计奠定了理论基础。

英文摘要：

The kinematics performance analysis and optimal design of 4-UPS-RPU（ 4-universal jointsprismatic pairs-spherical joints/revolute joints-prismatic pairs-universal joints） redundant actuation parallel mechanism was studied. The Jacobian matrix of the mechanism was established,and the three dexterity measures,which were conditional number,the smallest singular value and operation,were obtained. On this basis,the global dexterity coefficient,which was used to evaluate the dexterity of various configurations,was defined. And the distribution of different dexterity measures when parallel mechanism was kept in different attitudes,such as in single attitude of different Euler angles α and different Euler angles β,at the same Euler angle α and different Euler angles β,in the workspace were analyzed,respectively. Finally,based on the global dexterity coefficient,the structure parameters which include the distribution angle on stationary platfrom and motion platform and the distribution radius on stationary platfrom and motion flatfrom,were optimized by genetic algorithm. Compared with the global dexterity coefficient before and after optimization,it was found that the global dexterity coefficient after optimization was bigger than that before optimization. Thus the kinematic performance of 4-UPS-RPU redundant actuation parallel mechanism after optimization was much better than that before optimization,and the optimized effect was obvious. This research can provide important theoretical base of the structure design for the redundant actuation parallel mechanism.