Acceleration analysis of multi-rigid body system and its application for vehicle based stabilized platform system

The traditional representation of acceleration of a rigid body is given in terms of the angular acceleration and linear acceleration of a point attached to the rigid body. Since this representation has no coordinate invariance, the acceleration transformation of a multi-rigid-body system is complicated. In this paper, the physical meaning of the time derivative of a twist is investigated. It reveals that the rigid-body acceleration comprises the angular acceleration and tangent acceleration of a point which is attached to the rigid body and instantaneously coincident with the origin of frame in use. Their composition presents a six-dimensional representation of the rigid-body acceleration, which is verified to be of coordinate invariance. Based on the representation, the transformation of the rigid-body accelerations is performed conveniently, and the corresponding formula of composition accelerations of one rigid body relative to any other bodies in a multi-rigid-body system is presented. The method is then extended to the application of a vehicle stabilized platform system. The method is verified to be effective by analyzing the virtual prototype of the vehicle-based stabilized platform system. This paper builds a bridge for the six-dimensional rigid-body acceleration from theory achievements to practical application.