Study On Four Wheel Steering By Co-Simulation

Four-wheel steering technology as a contemporary automobile development, through an important direction of car front wheel steering wheel steering control and at the same time to improve cars, and the vehicle steering control stability of had been improved. Based on the model with four-wheel steering and control strategies for research object, discussed the four-wheel steering in handling stability superiority.The main contents this thesis can be summarized as follows: Because of the nonlinear tire of vehicle has a great influence in handling stability, but it is difficult to model in Simulink,, therefore this paper by using dynamics simulation software ADAMS establishes vehicle model based on virtual prototype technology, then establish four-wheel steering model by neural network in MATLAB/Simulink, and unite virtual prototyping model with neural network model, and by using fuzzy theory control the sideslip angle. so the model of four-wheel steering united can be made. Program is as follows;Firstly, four-wheel steering control system model can be established, and through the neural network training rear controller of four wheel steering vehicle can be got, and then realize vehicle steering according to certain control method to rear steering.Secondly, by using fuzzy theory control the sideslip angle with PID, and make the handling stability of vehicle system controlled, and vehicle has better adaptability.Again, establish the vehicle dynamic model in ADAMS/View, which include body, tire model, suspension system, road model and steering。 After that, using different four-wheel steering control method, analysis the mechanical system united with control system under the input of certain front wheel steering angle and certain speed and compare with them, thus draws sideslip angle and yaw velocity, gets the validity and reliability compared with the united simulation control strategyFinally, through changing the parameters can obtained the influence which vehicle quality and the position of centroid made, the result show control system has a good stability and adaptability.To sum up, through the simulation results that co-simulation has good control stability than front wheel steering, proportional control four-wheel steering, feedback control four-wheel steering, and yaw velocity control for four-wheel steering vehicles, which can provide theoretical studies of some ideas.