Dynamic Analysis And Improvement Of Vehicle Elastic-Suspension System

Vehicle elastic-suspension system generally refers to a kind of elastic connect devices in automobile, it contains elasticicty and damping components. It is used as a buffer and energy absorber between the connected units, and transmit force and torque at the same time. Vehicle elastic-suspension system is widely used in vehicle industry nowadays. Typically, such as engine mounting system and suspension system, they has a close relationship with vehicle carborne coustic comfortability、ride performance and handling stability performance, they are important factors of influencing full car quality, and they plays an important role in modern vehicle design. In fact, dynamic anysis and improvement of vehicle elastic-suspension system has become an indispensable technological link in the process of platform and seriation new vehicle development.Under the guidance of relevent theories in automotive engineering, this dissertation synthtiecally used funcional virtual prototyping method、response surface method、rigid-elastic coupling anasyis and the theories of optimization method, the design and development are under the background of certern automotive type. This dissertation studies some key problems in the process of dynamic anaysis and improvement of vehicle elastic-suspension system. While proposing technology solutions for project application, it has succeeded in solving actual real technological difficuty in product development, and has offered direct technical support for industrialization process of relevant enterprises. The concrete research contents mainly include:(1) The general technological procedure in dynamic anaysis and improvement of vehicle elastic-suspension system. Including basic theory of dynamic anaysis of elastic-suspension system and the procedure for improvement design.(2) Optimization of engine mounting system. A rigid model and a rigid-elastic coupling model are bulit separately based on functional virtual prototype method. By comparing simulation of this two models to find the similarities and differences, and improved this engine mounting system based on the results.(3) Optimization of suspension system. The estimation of the deficient basic data in buliding functional virtual prototype model, and using response-surface method to optimize this model.In the course of above-mentioned research, a series of innovations for application was obtained, mainly as follows:(1) The study and application of general technological procedure in vehicle elastic-suspension system dynamic anaysis and improvement, mostly carried out by relevant enterprises abroad, and research achievements which worthy of application usually in the rang of secret. Our country is still at the starting stage in this field, so there are very few articles to use for reference, and must to lunch innovative research. This dissertation treat the deep understanding of basic theories and technology for dynamic anaysis and improvement of vehicle elastic-suspension system as a breakthrough point, proposed a general technological procedure on the basis of holding its inner relationship between relevent technological links, and it is used as a guideline for the follow-up anaysis and reserch.(2) For the problem of lack basic data in building functional virtual prototype model, this dissertation used the moments of inertia of the body as example, by testing the natural frequency of full-car suspension system, and with combination the technology of optimazation proposed a method to estimate the moments of inertia of the body. It offered a new way to solve the problem above- mentioned.(3) When study the relationship between vehicle suspension system and full car handling stability performance, the possibility to optimize the simulation model directly is limited by the complexity of the model. This dissertation used the relationship between turning wheel orientation parameters and performance of vehicle return-ability as a example, a response surface model is established’ between these two aspects by simulation. Through the optimization of this response surface model, solved the insufficient return-ability problem of certern type of military special vehicle.(4) Using the method of rigid-elastic coupling in build engine mounting system virtual prototype. A method of interior low frequency acoustic anaysis which iscaused by engine vibration is put foward, and proposed a optimization method of engine mounting system. Based on the results of optimization, it offers an useful technique scheme for project improvement.