Analyzing way for elastic body in MBS based on superelement method
By the use of theories of Finite Element Method(FEM) and multibody system(MBS), the kinematics expression of elastic body in multibody system, its elastic deformation described with Rayleigh-Ritz method and its equation of motion based on d'Alembert law and Jourdain's virtual power principle are studied in detail. And the processing method to express the characteristic information of elastic body with FE means and to apply the information in vehicle system are also studied and analyzed. Based on above theories, the complete FE model of a frame in vehicle system is condensed by the superelement method, which greatly reduces the DOF of frame expressed in multibody system. And the precision of results is guaranteed simultaneously. Solutions of the frame show that the method presented here can solve elastic body in vehicle system exactly and fast, and has high precision, stability and reliability in concerned frequency range to meet the need of scientific researches and the practical analysis of structural vibration.