Dynamic Analysis And Comfort Evaluation Of The Vehicle-road Coupled Vibration System

According to the actual situation of the vehicle driving on the road, the vehicle-road system is divided into3subsystems, including "the simplified vehicle vibrating model","the stress contaction model of tire and road", and "the dynamic response model of the rigid road structure". The dynamic analysis model and balance equation of the vehicle-road system are established, and the interaction and dynamic response of the system are studied theoretically. The human body is added to the vehicle-road system, and the interaction between the body and the vehicle is consided. The riding comfort of the vehicle is evaluated by analyzing the acceration of the human body. The influences of external incentives on the human-vehicle-road system, such as vertical environment vibration, side wind load and so on, are also discussed. The research results will lay the foundation for the vehicle design for improving the riding comfort.The main research contents below:1, Road roughness is the most important reason which causes the vibration of vehicle-road coupling system. Two simulation methods of the road roughness are introduced. And then based on the power spectral density of road roughness, the various kinds of road roughness is simulated by the triangle progression method and inverter replacement method.2, The coupling vibrating analysis model of vehicle-road system is built, and the dynamic balance equations of the there subsystems are deduced. The equations are solved with the modal superposition method and the finite element methods, and its matlab program is prepared using the gradually integral method. With the calculation example, the accuracy of the model and procedure is discussed. And the influences of the parameters of the vehicle, road, road-foundation, and the vehicle movement speed and road roughness value on the system are analyzed.3, The human dynamic model and the evaluating methods of the riding comfort are introduced. The coupling vibration equations of the body-vehicle-road are established, and the dynamic response and the riding comfort of the coupling system are analyzed; and the influences of the parameters of the vehicle, road, road-foundation, and the vehicle movement speed and road roughness value on the riding comfort are analyzed.4, Vertical environment vibration and side wind load are two important external forces of the vehicle-road system. The coupling vibration equation of the body-vehicle-road system under the vertical environment vibration and side wind load are established separately and solved with the numerical calculation method. The dynamic response of the system and the riding comfort of the vehicle are also analyzed. The parameters of the vertical environment vibration and side wind load on the vibration of the system are discussed.5, In order to accurately evaluate the riding comfort of vehicle, the traditional vehicle-road coupling vibration model are improved and the coupling vibration system of3d model for evaluating comfort is set up. The simulation results are compared with the traditional model, and the accuracy and necessity of the improved model are also discussed. In order to accurately analyze the influence of the external incentives on the vehicle-road system, the coupling vibration equation considering lateral sliding of the vehicles is established under the vertical and lateral incentives, and the necessity of coupling the vertical incentives with the horizontal incentives is discussed.