A Study On Simulation Test System Of Vehicle Ride Comfort Based On VR And Its Key Technology

Ride comfort is one of the leading performances on modern vehicle. In order to evaluate the vehicle ride comfort effectively, the project "The research on test and diagnosis based on virtual reality and virtual instrument" is excuted by the supporting of the Dean Fund Project od Zhejiang University. The system frame of vehicle performance test is established based on Virtual Reality method. And exploratory research work is carried out to solve the key problems on the development of virtual test system of vehicle ride comfort. The detail contents are as following.Chapter one is the introduction. The background and significance of project research are presented. The recearch statuse on vehicle ride comfort inside and outside are reviewed on part of the road surface performance, the test valuation method and the improvement in vehicle ride comfort. And the research status are analysed on applying VR to vehicle industry, especially in vehicle test. The main contents of the dissertation are also given here.Chapter two is the system design of vehicle simulation test based on VR. Based on the principles of openning, reusing and integration, the integrated system of combinning many tests and performance synthesis valuation is researched. Based on the summarization of the vehicle test technology and traditional test methods, the necessary is clarified about the method of vehicle vitual test, and the concept of vehicle vitual test is redefined, as well as the characteristic. According to similarity theory and VR technology, the idea and method of software design are introduced such as the object-oriented simulation, the software multiplexing and the distributing interactive simulation technology, and the system of vehicle virtual test is analysed and designed. Furthermore, the integrated simulation platform of vehicle virtual test is constructed.Chapter three researches the modeling mothod of stochastic road surface. First, the frequency-domain models and a few of time-domain models are introduced, and the ARMA model of stochastic road surface is researched, then the AR(p) model is established. According to the standard spectrum of road surface, the displacement power-spectrum of road surface is simulated. Based on the analysis of the generalized spectrum density of nonstationary random process, the necessary and sufficient condition of power spectrum density of nonstationary random process is presented.