基于工作空间的踝关节康复广义球面并联机器人运动学参数优化

为了解决现有踝关节康复机器人难以完全拟合人体踝关节运动的问题，在仿生学的基础上，提出了一种高匹配度的踝关节运动串联拟合模型，并研发了一款新型的三自由度广义球面并联机器人。为研究该并联机器人的拟合能力，基于螺旋理论分析了其自由度特性，建立了机构的运动学模型，并在逆运动学的基础上阐明该机器人具有部分解耦特性。根据机器人具有双球心的特点，求解了动球心和动平台可达工作空间。最后，以踝关节运动拟合模型的工作空间与机器人的工作空间的匹配度为目标函数，采用遗传算法对运动学参数进行了优化。对比研究机器人与模型的工作空间散点图，并求得有效工作空间比分别为0.79和0.86，结果表明优化后的广义球面并联机器人工作空间能够满足踝关节的运动要求。

Kinematic Parameter Optimization of Workspace-based Generalized Spherical Parallel Robots for Ankle Joint Rehabilitation

In order to solve the difficult problems for the existing ankle joint rehabilitation robots to completely fit the motion of the human ankle joints, a high-matching ankle joint motion series fitting model was developed based on bionics, and a new type of three degree of freedom generalized spherical parallel robot was proposed. In order to study the fitting ability of the parallel robots, the degree of freedom characteristics was analyzed based on the spiral theory. The kinematics model of the mechanisms was established, it was clarified that had partial decoupling characteristics based on inverse kinematics. According to the characteristics of the dual spherical centers of the robots, the moving sphere center and the working space of the moving platform were solved. Finally, taking the degree of matching between the working space of the ankle joint motion fitting model and the working space of the robots as the objective function, the genetic algorithm was used to optimize the kinematic parameters. The working space scatter plots of the robots and the model were compared and the effective working space ratios were obtained as 0.79 and 0.86 respectively. The results show that the optimized working space of the generalized spherical parallel robots may meet the motion requirements of the ankle joints.