The Research Of Dynamic Load Identification Of Simple Multibody System

a lot of researches have been done on modeling and control of multibody systems. But , the report about load identification of multibody system have not been seen. Multibody system is unlinear, the previous method for load identification are all proposed to linear system, noone have done research for unlinear system. In the paper, we done reasearch for the dynamic load identification of multibody system which consist of a cantilever beam and a rotating beam.First of all, we model for the multibody system in two different methods, one is hybrid coordinate method the other is traditional KED method. We can know from the process that the model based on the hybrid coordinate method take rigid-flexible coupled into account, and the mass matrix contains elastical deformation coordinate and the model is unlinear. The model based on the KED methods don’t consider the rigid-flexible coupling and the model is close to linear, but the system matrix is still time varying. For the two models, we match the load by orthogonal polynomial and derive dynamic calibration matrix in time domain, then we can obtain coefficient and identify load. In the paper, we identify the dynamic load of unliear system in the method for linear system. We can find problem and limitations of the way and we can analyse the effect of rigid-flexible coupling to identification result from the difference between two models. Besides,we can also find the problem caused by driving torques.At last, we design a working condition which can be realized by test and simulate for the working condition, analyze the effect in the load identification of different factors thus, we can propose reference for the lateral test and lay foundations for future work.