Simulation Analysis And Optimization Design Of The Car Ride Comfort Based On Virtual Prototype Technology

Vehicle ride comfort is one of the prime performances of modern high-speed and high-comfort vehicle. Moreover, it is also one of the most important indices that determine the vehicle whether it has the advantage in the market competition. Nowadays, most researches about vehicle ride comfort are only based on the multi-rigid body dynamics method, but not consider the affection of the flexible body. These lead to the result being some differences with the truth. So it is significant and has the engineering practical value to develop the dynamics research of rigid-flexible coupling system.This dissertation focuses on the simulation study of the vehicle ride comfort by theoretical foundation of rigid-flexible coupling system dynamics, and brings forward the research thought of using fixed interface dynamics substructure method to analyze the rigid-flexible coupling system. Taking a car of certain model as an example, the multi-body dynamics models which include front suspension, rear suspension, powertrain, chassis, steering system, tires and the random road model are established with the vehicle dynamics analysis module ADAMS/Car in the multi-body dynamics software of ADAMS, and whole vehicle model is established based on these models. To improve the accuracy of the model, the flexible model of body is established with the HyperMesh software, and it is pretreated by cohesion function on the super element theory, then it is imported into ADAMS software to generate the flexible modal which is connected to the multi-body dynamics model of a chassis to establish the rigid-flexible coupling model. In the same simulation circumstance, ride comforts of two whole vehicle models including multi-body dynamics and rigid-flexible coupling are compared and. The simulation results show that the methods of using the rigid-flexible coupling to study the ride comfort is better than that of using the multi-body dynamics and it's necessary to establish the rigid-flexible coupling model in studying the ride comfort.At last, the Test Ride to the car on the physical prototype is carried out. Comparison between simulation results and test data indicates that the built simulation model is correct. And then the dissertation optimizes the suspension parameters of the rigid-flexible coupling model of full vehicle by Design of Experiment (DOE) in ADAMS/Insight. According to the methods of evaluating ride comfort of the national standards, simulation results of the original parameters and optimized parameters of vehicle suspension are compared and analyzed. The results show that the vehicle ride comfort is improved obviously.