Abstract:  Aiming at the problems that the coupling effect of multi-joint series mechanisms on the kinematic performance of the end-effector， the kinematic characteristics of series-parallel hybrid mechanisms were analyzed， and a multi-parameter plane model was proposed to realize visualized design. Based on screw theory， the kinematics transfer matrices of serial and parallel joints were established respectively， and the corresponding performance indexes were set up. According to the multi-parameter plane model， the coupling relationship among parameter scale， orientation workspace， and performance indexes were further revealed through a three-dimensional visualization graphics. Finally， the values of parameters， the range of high-quality orientation workspace， and the distribution of indexes were confirmed. The results show that the global performance indexes of the shoulder and wrist joints are as 0.78 and 0.67， respectively， and the global condition number of the elbow joint is as 2.38. The hybrid configuration has functions similar to that of the human arm joints， and gives full play to the comprehensive advantages of series and parallel mechanisms. 

Key words: humanoid robotic arm, hybrid mechanism, scale optimization, multi-parameter, performance index

摘要： 针对多关节串联机构耦合影响末端执行器运动性能的问题，分析了串并混联机构的运动特性，提出了实现可视化设计的多参数平面模型。基于旋量理论，分别建立了串联、并联关节的运动传递矩阵，并设定了相应性能指标。在此基础上，根据多参数平面模型，通过三维可视化图形，进一步揭示了参数尺度、关节转角空间、性能指标之间的耦合关系，最终确定了参数取值、关节的优质转角范围和指标分布情况。优化结果表明：肩关节、腕关节的全域性能指标分别为0.78、0.67，肘关节的全域条件数为2.38。该混联构型具有与人体手臂关节相类似的功能，可充分发挥串联、并联机构的综合优势。

关键词: 仿人机械臂, 混联机构, 尺度优化, 多参数, 性能指标