基于弹簧的绳驱动4-SPS/U刚柔并联式躯干关节机构设计与运动学建模

Design and Kinematic Modeling of Cable-driven 4-SPS/U Rigid-flexible Parallel Trunk Joint Mechanism with Spring

结合绳驱动和刚性并联机构二者的优点,采用过约束并联机构的构造方法,提出了一种2自由度绳驱动4-SPS/U刚柔并联式躯干关节机构。该躯干关节机构可以使6足移动机器人灵活地实现行走、水中推进、攀爬以及滚动等多种运动模式。利用螺旋理论计算了绳驱动4-SPS/U刚柔并联式躯干关节机构的自由度;结合封闭矢量方法和特征结构配置解耦法构建了该机构的运动学逆解模型,推导出该机构的速度和加速度模型,并通过雅克比矩阵分析了机构奇异性。通过理论数值方法计算出该躯干关节机构的位移、速度和加速度理论仿真数据,将理论仿真数据与Adams软件仿真数据进行对比,从而验证了理论模型的正确性。

A two-degrees-of-freedom cable-driven 4-SPS/U rigid-flexible parallel trunk joint mechanism is proposed by using the construction method of over-constrained parallel mechanism,which has the advantages of wire-driven mechanism and rigid parallel mechanism.A mobile hexapod robot which is composed by the trunk joint mechanisms is established.The trunk joint mechanism can enable the hexapod mobile robot to flexibly realize various motion modes,such as walking,underwater propulsion,climbing and rolling.The degree of freedom of cable-driven 4SPS/U rigid-flexible parallel trunk joint mechanism is calculated by using screw theory.An inverse kinematics model of the mechanism is constructed by using the closed vector method and the decoupling method for eigenstructure assignment.The velocity and acceleration models of the mechanism are derived,and the singularity of the mechanism is analyzed by Jacobian matrix.The theoretically simulated datum of displacement,velocity and acceleration of trunk joint mechanism are calculated through theoretical numerical examples,and the theoretically simulated datumare compared with the simulated results of Adams software,which verifies the correctness of the theoretical model.