具有滑移铰约束多体系统的动力分析

Dynamic Analysis of Flexible Multibody Systems With Sliding Joints

针对具有滑移铰约束的多体系统对每个物体建立一个牵连坐标系，该坐标系与惯性参考系原点相固连，且与物体坐标系时时平行。物体的刚体平动在牵连系中以相对运动进行度量，而弹性运动仍在物体坐标系中度量。该坐标系充分利用了坐标变换矩阵的正交性，从而实现刚体运动与弹性运动的分解，降低刚弹耦合非线性；同时该坐标系为约束方程的描述以及物体的有限元描述都提供了极大的方便。数值计算结果表明，该方法是解决具有滑移铰约束的多体系统动力分析问题的有效方法。

Focussing on the flexible multibody systems with sliding pins, a carrier coordinatesystem is set up for each body of the system, which is fixed on the origin of the reference co-ordinate system and always parallel to the body coordinate system. The rigid motion of thebody is measured in its carrier coordinate system and the elastic deformation is described inthe body coordinate system, so that the orthogonality of the transformation matrix is fully u-tilized and the nonlinear couplings between rigid motion and elastic deformation are greatlyreduced. Further more, it also provides great convenience to describe the constraint equa-tions and the elastic motions. Numerical method is discussed with an example.