【摘要】 研究了一种用于下肢康复的3自由度冗余驱动并联机构的概念设计和运动学优化.首先对该3自由度并联机构进行了简要介绍,然后推导了其运动学正逆解的解析解.基于螺旋理论,对该机构进行了广义雅可比分析,通过对4种非冗余驱动情形的力/运动传递性能分析,提出了一种用于评价该并联机构运动学性能的局部传递率指标.最后,借助于遗传算法,通过最大化局部传递率指标的全域平均值对该机构的设计变量进行了优化.运动学优化的结果表明,本文所提出的并联机构在其工作空间内具有较好的力/运动传递性能.更多还原

【Abstract】 The conceptual design and kinematic optimization of a redundantly actuated three degrees of freedom(DOF)parallel mechanism for lower-limb rehabilitation were studied in this paper.First,a brief description of the proposed 3-DOF parallel mechanism was presented.Then,the explicit expressions of inverse and forward kinematics of the mechanism were derived.By using screw theory,the generalized Jacobian analysis was carried out,based on which the force/motion transmissibility of the redundantly actuated parallel mechanism was investigated via four individual cases without actuation redundancy,leading to a local transmission index for the evaluation of kinematic performance of the proposed mechanism.Finally,the design variables of the mechanism were optimized by maximizing the mean value of the local transmission index with the aid of genetic algorithm(GA).The result of the kinematic optimization shows that the proposed parallel mechanism can achieve good force/motion transmissibility in its workspace.更多还原