弹性铰平面闭环六杆机构刚度特性研究

Stiffness Characteristics Research of Closed-chain Six-bar Mechanism with Flexible Joints Based on Influence Coefficient

为研究弹性铰平面闭环六杆机构的刚度特性,运用影响系数法求解了闭环机构的Jocabian矩阵和Hessian矩阵,借助虚功原理同时考虑主动、被动铰链弹性变形,建立了机构约束方程,推导出机构的刚度矩阵。结合刚度矩阵的瑞利商定义了刚度判定指标K,绘制出刚度性能空间图,进一步研究了操作端方向的刚度特性。

In order to investigate the stiffness characteristics of planar closed-chain six-bar mechanism with flexible joints, the paper solved Jacobian matrix and Hessian matrix of the closed-chain mechanism with the method of influence coefficient. Based on the principle of virtual work, the constraint equation of the mechanism was established, considering deformation of active and passive flexible joints, and the stiffness matrix was deduced. Combining Rayleigh quotient of the stiffness matrix, the paper defined the index K used to estimate the mechanism stiffness, and plotted spatial graph of the stiffness performance. In additional, the directional stiffness characteristics of the mechanism was discussed. So, a novel and general method are raised for analysing stiffness of closed -chain mechanism with flexible joints.