基于伪刚体模型法的全柔性机构位置分析

KINEMATICS ANALYSIS OF FULLY COMPLIANT MECHANISMS USING THE PSEUDO-RIGID-BODY MODEL

柔性机构是一种依靠构件元素的弹性变形传输所希望运动的机构。具有集中柔度的全柔性机构是其中的一种类型，其特征是机构中传统形式的铰链全部被柔性铰链所代替。对它的研究，近年来也已成为一个热点。为探索这类全柔性机构的运动学问题，首先建立起柔性铰链变形刚度模型。在此基础上，提出了一种扩展的伪刚体模型法，很好地解决了机构的位置正、反解问题。

Research on compliant mechanisms and fully compliant mechanisms has been a hot issue in recent years. The kinematics analysis of fully compliant mechanisms is discussed. Because of spherical joint in this mechanism, the method of pseudo-rigid-body model which has been extensively used in the analysis and design of the compliant mechanisms with only revolute flexure joints is limited in analyzing its kinematics. In addition, the method of finite element analysis is also very complicated. So an expanded pseudo-rigid-body model method is presented. To specify it, the stiffness models of the flexible joint by using the displacement matrix method in structural analysis are established firstly. The close-loop displacement equations of mechanism are derived through the transformations of a series of coordinate systems. Thus both the forward and inverse displacement solutions of the mechanism are presented.