| Automobile is a complex multi-degree nonlinear system which contain many stretch and damp parts. The system will engender stochastic vibration because of the rough road and the engine. The vibration will directly affects the stability, softness and the life of parts, so it is quite important to minish the vibration as much as possible.The vibration from the road will be transported o the body by suspension system, so it is decided by the suspension system. The rigidity and damp in traditional passive suspension will be chosen by some usual drive statement, and they can not be changed as soon as the suspension is assembled on the automobile. It is a eclectic way between automobile stability and softness. It will suits the car only in some special drive statement. Because the structures of traditional passive suspensions are simple, and they are lighter, take less space, so they are still the main type that are used in internal automobiles now. In order to enhance the ability of traditional passive suspension, we will adjust the rigidity and damp of suspension in case the automobiles have good drive stabilities. So when we have made sure the good drive stability, it comes to be a quite applied subject to enhance the ride softness as much as possible.The paper is mainly based on the problems on vibration noise occurred in the suspension system of JL7135sport-car sedan. Based on the theory of Multi-body System Dynamics, the car and road models were built by using Large-scale mechanical system dynamics simulation analysis software -SIMPACK automotive block. Some emulation and analysis research work on the automotive ride comfort in dummy environment were done.A lot of experiments were done in order to assure the veracity of the models. By doing this, a lot of parameters were gotten such as the parameters of mass, constructure, the orientation of front and rear wheels and the suspension performance parameters. These parameters supply the basis of the models and the calculation.Based on the research work in this paper, the real road experiments on ride comfort were done according to GB 4970-1996 with an excellent JL7135sport-car sedan, and got the response of the real car. Validated whether the models and the simulation were correct by comparing the results between simulation and experiments. The results of nonlinear system were more like the results of experiments, which showed that the nonlinear system was more similar as the real car.With the precondition of correct models, the dynamic deflection and relative velocity of suspension system were particular analysed by SIMPACK. Ride comfort of the projects in which different absorber were used were analysed also, and got the best absorber matching project, which strongly support the design of the absorber damp characteristic.Three absorber damp characteristic projects were designed and simulated in different road conditions and velocities about ride comfort. The absorber damp characteristics were also analysed in time origin and frequence origin, so suited absorber damp characteristic was chosen to get the best matching of the suspension damp parameters. Both the front suspension and rear suspension were matched.The practical problems are solved by the research works. We also do some more matching analysis and experiments works for JILI group under the environment. We also get more skill and experience which will be the foundation for resolving more NVH problems in the future.
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