3-SPS/S球面并联髋关节机构奇异位形与静力卸载分析

SINGULARITY CONFIGURATION AND MECHANICS UNLOADING ANALYSIS FOR 3-SPS/S SPHERICAL PARALLEL MECHANISM OF HIP JOINT

结合人体髋关节的实际结构与功能特性,选取3-SPS/S(S为球面副,P为移动副)球面并联机构作为仿生髋关节原型机构,求取机构运动学反解,建立奇异轨迹方程,绘制奇异轨迹曲线;运用矢量法建立机构各构件的静力平衡方程,通过数值算例绘制机构各支链受力随位姿变化曲线,分析中心支链卸载效果;借助Adams软件对机构进行仿真,以获取在预定运动轨迹下机构各分支铰链所受力随时间的变化曲线,从而进一步验证机构静力卸载功能。研究内容对人形机器人髋关节样机的研制与控制具有一定的理论指导意义。

Combined with the actual structure and function characteristics of the human hip joint, 3-SPS/S （S for spherical pair, P for prismatic pair） spherical parallel mechanism is chosen as the prototype for the hip joint. After the inverse kinetic solution was solved, the singularity trajectory equations were established and the singular tracks were plotted. The static equilibrium equations of each component of the mechanism were established using the vector method. The curves of the exerted force on branches with the variety of poses were plotted by numerical examples, and then the mechanics unloading effect of the middle limb was analyzed. Through simulation analysis of the mechanism with ADAMS software, the force-time curves of the hinges fixed to the mechanism ＇ s branches corresponding to prescribed trajectory were obtained, which verified mechanics unloading function of mechanism. The research contents should possess certain theoretical guiding significance for the development and control of the hip joint of the humanoid robot.