弹性铰平面并联三自由度机器人连续刚度映射研究

Research on continuous stiffness mapping of planar parallel 3-DOF manipulator with flexible joints

应用影响系数法求解了弹性铰平面并联3-RRR机器人的一阶、二阶影响系数,借助虚功原理建立了包含主、被动铰链弹性变形,杆件及其平台自重的连续刚度映射模型。与以往刚度模型区别在于,该连续刚度模型考虑了机构刚度变化的动态过程,从而使并联机器人刚度非线性映射还原。文中还结合刚度矩阵瑞利商定义了连续刚度判定指标,绘制了刚度性能空间图,进一步探讨了该机构的方向刚度特性,为平面并联弹性铰机器人机构刚度的分析提供了一种新颖通用的方法。

The In＇st-order and second-order influence coefficient of planar parallel 3-RRR manipulator with flexible joints were solved with the method of influence coefficient. Based on the principle of virtual work, continuous stiffness mapping model including the deformation of active and passive joints and gravities factor was established. Different from the traditional model, the stiffness nonlinear mapping was reverted considering the stiffness dynamic change. Combining Rayleigh quotient of the stiffnesss matrix, the index k used to estimate the manipulator continuous stiffness was defined, and spatial graphs of the stiffness performance were plotted. In addition, the direction stiffness characteristics of the manipulator were discussed. So, a novel and general method are raised for analysis stiffness of planar parallel mechanism with flexible joints.