新型球面并联人形机器人踝关节机构静力学性能分析

采用拆杆法建立机构的静力学平衡方程，考虑构件弹性，利用小变形叠加原理建立机构的变形协调补充方程，进而完成二自由度并联人形机器人踝关节机构的静力学分析。通过数值计算，得到在三种外载荷下构件上的各力与机构位姿的关系图。结果表明:外载荷为纯力时，支链1的受力很小，支链2的受力近似为零，而中心球面副支链的受力近似等于外载荷;外载荷为纯力矩时，三个支链的受力情况相似;外载荷为力和力矩时，支链1、支链2的受力情况与外载荷为纯力矩时的受力情况相似，中心球面副支链的受力为前两种情况的叠加。外载荷中的力成分主要由中心球面副支链承载，力矩成分由三个支链共同承载。该研究为该人形机器人踝关节机构在工程中的结构设计与应用提供了静力学参考。

Statics Property Analyses of a Novel Spherical Parallel Humanoid Robotic Ankle Mechanism

By the dismantle-bar method, the statics equilibrium equations of the mechanism were set up, considering the elasticity of member and then utilizing the micro-deformation and superposition principle, the deformation equations of compatibility were derived and then the statics analyses of the 2-DOFs parallel humanoid robotic ankle mechanism were fulfilled. As a numerical example, some figures which showed the relationship among each force on each member and the position and posture of the mechanism were drawn under three kinds of external loads, respectively. The results show that, under the external forces only, the forces acting on branched chain 1 are very small, the forces acting on branched chain 2 are approximately zero, and the forces acting on central spherical pair branched chain approximately equal to the external force. Under the external torques only, the force conditions of three branched chains are similar. Under external forces and torques, the force conditions of branched chain 1, 2 are similar to the force conditions that under the external torques only, the forces acting on central spherical pair branched chain are the superposition of the two forces in the above two cases. The force portions of external load are mainly carried by central spherical pair branched chain, the torque portions are jointly carried by three branched chains. The research provides a theoretical basis of statics for structure design and applications of this humanoid robotic ankle mechanisms in engineering．