Investigation On Dynamics Simulation Of Transmission Based On Virtual Prototyping Technology

Since transmission is an important component of vehicle's power train, thecharacter in kinematics and dynamics of transmission is related to the reliability ofvehicle directly. The application of virtual prototyping technology not only improvessimulation technique's precision, but also saves the time. Taking example for a transmission used in vehicle, the key steps and approachesof dynamic simulation on the transmission based on virtual prototyping technologyare discussed. This thesis makes a deep research on the dynamics simulation methodsof the gear-rotor-bearing system and the synchronizer mechanism. The simulationresults are more precise, and this method is very useful for the practical design. Themain points of the thesis are listed below. Firstly, assembly model of the transmission is built in the UNIGRAPHICSenvironment. Based on the assembly model, UG Scenario is put up for kinematicallyanalyzed, simulated and animated. Interference check in the motion process indicatesthe transmission's geometry parameters are reasonable. Synchronizer is an important device of transmission. In the thesis, average radiusof friction cone in synchronizer is presented. Some important parameters in thesynchronizing process are calculated, and then the process is simulated in theMSC-ADAMS environment, furthermore, the two results used different method iscompared and analyzed. Some parameters used in simulation of exciting force in both spur gears andhelical gears are presented based on Hertz formula. Then, the multi-body dynamicssimulation model of the gear train mechanism is established in the thesis. Theconsistency of the simulation result and the calculated result indicates that themagnitude and frequency of the exciting force in gears is correct. The structural dynamics characteristics of the output shaft are analyzed throughboth the model test and the Finite Element Analysis. The consistency of the naturalfrequencies and modal shapes verifies the veracity of the FE model. Based on the FEmodel of the output shaft, the multi-body dynamics simulation model of the flexiblesystem is established in the thesis. Through the dynamics analysis of the flexiblesystem, the bearing impact is acquired, which is the basis of the further analysis of thestress and stiff analysis on shafts and bearings.