Research On Steer-by-Wire System Of Light Vehicle

Steer-by-wire system (SBW) gets rid of the constraints of the traditional steering system, can be freely designed according to the demand of automotive steering system force transmission characteristics and transmission characteristics of the steering angle, can change the sense of feedback from the road , because of the abolition of the mechanical connection between the steering wheel and steering Wheel(through signals to connect).It had improve the vehicle's steering performance, it showed great advantages than the traditional mechanical steering system, there will be broad space for the development of the SBW.In this paper, the study set up dynamic model of the steer-by-wire to implement the electric motor and a sense of road modeling and control, and the steer-by-wire control algorithm based on the of research results at home and abroad. To structure and to improve the bench units for the experiment, this paper did the following work:The first chapter describes the development of automotive steering system development process and the status, the introduction of steer-by-wire development at home and abroad, the level of development, as well as the study meaning of the steer-by-wire.The second chapter introduced the basic structure and working principle of the steering-by-wire system. Units introduce the composition of the experiment. Among them, the implementation of the motor are purchased after careful inspection of the market, the type and performance requirements are in line with the bench to ensure the progress of the experiment.Chapter III, constructs the models system of the steer-by-wire by the application of Matlab/Simulink software based on the theory of the reduced-order modeling methods. Model system privodes the foundations for the validation of motor control strategy and the control algorithm of the steer-by-wire.Chapter IV, researches on the steering control strategy, analysis and comparison of several commonly used electrical current control algorithm, analysis of the PID and fuzzy-PID control algorithm, compares the advantages and disadvantages of the algorithm. Analysis of the control strategy of "road-feeling" for the steering-by-wire system, analysis of the target front-wheel steering angle of the steering-by-wire steering system. The strategies for the control algorithm is verified.Secondly, study the front-wheel steering angle control strategy. Simulation tests show the contrast between the control strategy by the feedback of the yaw angular rate and the lateral acceleration based on the ideal transmission ratio and the control strategy feedback of the yaw angular rate based on the ideal transmission. The simulations show that this method is better than just the concept of the ideal transmission ratio control strategy or control strategy feedback of the yaw angular rate based on the ideal transmission, improved the vehicle handling and stability.To sum up, this article get acknowledge of the steer-by-wire on the basis of the information at home and abroad, research on the steer-by-wire control strategy and control algorithm based on Matlab/simulink model of the steering system, and the research of the target front-wheel steering angle based on the feedback of yaw angular velocity and lateral acceleration, And the simulation shows that this control strategy can have a more better track of the lateral acceleration of the car, and can give the driver a more realistic sense of the way information contrast with the control strategy based on the feedback of yaw angular velocity.Finally, sums up the contents of the text, and bring up the need for the further work.