Flexible Coupling Dynamics Of Many-body System, And Its Launch System

The dynamics modeling theory and simulation of rigid-flexible coupling system is studied in this dissertation.The dynamic problems of the rigid-flexible coupling system are quite different from the dynamic problems of a multi-rigid-body system, in which the complexity is shown as the coupling system between the large overall rigid motion and the small elastic deformation. Kane studied the elastic beam model with large overall motion and introduced the concept of Dynamic Stiffening. The coupling deformation term, which is produced by the couple of deformation in lognitudinal and in transverse direction, is the key of Dynamic Stiffening.Based on the theories of multi-body systems, the subsystem method for dynamics modeling of a rigid-flexible coupling system is presented. A complex system is divided into several simple subsystems firstly and then the dynamic model of the whole system is made up of the existing dynamic models for simple subsystems, which can avoid the complexity of modeling and make the modeling procedure more efficient and the coupling degrees of dynamic equations lower than that of traditional methods.The dynamic models of a flexible cantilever beam, which is attached to a moving central rigid-body with an arbitrarily three-dimensional large overall motion and a central rigid-body, flexible beam with tip-mass are discussed through differential element method. The approach of assumed modes is used to discretize models to obtain dynamic equations with coupling deformation term. And also the dynamic characters and simulation of a multibody launching system are studied with flexible effect of the launcher tube in this dissertation.