复合载荷作用下柔顺机构的PR伪刚体新模型

New PR Pseudo-rigid-body Model of Compliant Mechanisms Subject to Combined Loads

基于伪刚体模型,综合考虑平面柔顺机构中柔性杆件的横向变形和轴向变形影响,提出具有移动副的两自由度伪刚体新模型。分别用移动副和转动副描述柔顺杆件的轴向位移和横向位移,模拟末端受力和力矩复合载荷作用时柔顺杆的变形,建立平面柔顺机构的PR伪刚体模型,通过三维搜索得出了模型的最优特征半径系数,应用线性回归方法得到了模型的刚度系数。通过与1R、2R伪刚体模型以及柔顺杆的数值算例对比,说明了PR伪刚体模型的优越性。

Based on the pseudo-rigid-body model （PRBM）, a new 2-Degree of freedom pseudo-rigid-body model with a prismatic pair is proposed. The axial displacement and lateral displacement is presented by the prismatic pair and revolute pair, respectively, and so the deflection of a compliant link subject to a combined force and moment loads can be simulated. The PR pseudo-rigid-body model of planar compliant mechanism is developed. A three-dimensional optimization for the characteristic radius factors and a linear regression method for the spring stiffness coefficients are presented. The advantage of the PR pseudo-rigid-body model is illustrated numerically through the comparison with the 1R, 2R PRBM models and compliant link.