空间全柔性机构位置分析的刚度矩阵法

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.由于空间全柔性机构中存在球副,使得目前通用的伪刚体模型法受到限制,为此提出了一种扩展伪刚体模型法.并以6-RSS并联全柔性机构为例对其位置解问题进行了分析:首先利用结构分析中的位移法建立起柔性铰链的刚度模型,同时通过一系列坐标系的建立和转换,建立起机构的变形协调方程、位置闭环方程及静力平衡方程,进而求得机构的位置解.该方法充分考虑了机构中弹性构件的变形,所得结果更接近实际.

Stiffness Matrix Method for Displacement Analysis of Fully Spatial Compliant Mechanisms

Because of spherical joints existed in some spatial mechanisms, the pseudo rigid body model method extensively used in the analysis and design of a compliant mechanism with only revolute flexure joints was very limited in analyzing its kinematics. An expanded pseudo rigid body model method named as stiffness matrix method was presented to conduct the displacement analysis of fully spatial compliant mechanisms. Take a 6\|RSS mechanism for instance, the stiffness matrix of the general flexure hinge was established by using the displacement matrix method in structural analysis. Through the transformations of a series of coordinate systems, force\|balance equations of nodes and end\|effector of the mechanism, deformation cooperation equations and close\|loop displacement equations of the mechanism were derived. On the above basis, displacement analysis of the mechanism was conducted with the stiffness matrix method, giving a relatively higher accurate solution by considering elastic deformation of all the mechanical members.