Study On The Virtual Testing System Of Vehicle Vibration Based On VR

Centered on the study on virtual testing system of the vehicle vibration based on virtual reality (VTSVVBVR), this dissertation proposes the theory framework of the virtual testing system based on VR (VTSBVR), establishes the system framework of the VTSVVBVR, researches its model subsystem, road roughness models, virtual instrument (VI) subsystem, virtual reality (VR) subsystem, and the implementation of the VTSVVBVR. The contents include:Chapter 1 is the introduction part. Firstly, the concepts, characteristics, history and state-of-the-art related to the study on VR, VI, virtual testing (VT) , and the state-of-the-art of road roughness are introduced, then the study significance and the study details of the VTSVVBVR are expounded, followed by the innovations of the dissertation. Finally, the main contents and the architecture of the dissertation are given.Chapter 2 focuses on the the system framework of the VTSVVBVR. Firstly, the concept of the VTSBVR is given, and the theory model and the theory framework of the VTSBVR are established. Then the system framework of the VTSVVBVR is established and the testing system of vehicle vibration is studied. Finally, the implementation method of the VTSVVBVR are given.Chapter 3 researches the establishment of the model subsystem of the VTSVVBVR, including the establishments of the geometry model, the kinetic model, and the vehicle vibration model.Chapter 4 discusses the modeling of the road roughness, including the road roughness, road roughness models, the discrete wavelet transform (DWT), the maximal overlap discrete wavelet transform (MODWT), the establishment of the road roughness model of fractionally differenced (FD) process based on DWT, the recognition of the parameters of FD process model of the road roughness, the locating and extracting of the road roughness abrupt changes, as well as the simulation of the road roughness with abrupt changes.Chapter 5 establishes the VI subsystem and the VR subsystem of the VTSVVBVR. Firstly, the evaluation of the vehicle vibration, data processing, and the solution method of the mathmatical model of the vehicle vibration are studied. The design of the virtual instrument panel is studied. Then the Desktop VR is adopted as the VR subsystem, and the VR software, WTK9.0, is selected. WTK, the inner coordination of the application and some methods related to MATLAB computing are used to implement the VR and VI subsystem. Finally, VTSVVBVR is implemented, which has shown that vehicle vibration excited by different kinds of road roughness, and the corresponding vehicle vibration signals of time domain, wavelet domain, and Fourier frequency domain, the weighted vibration level and the vibration evaluation could be observed simultaneously in three observation models respectively by the aid of the system, which accord the expected results.Chapter 6 is a summary of the contents of this dissertation and a discussion of the works to be further updated in the future.