Unmanned Cars Following Control By Leader-follower Method

This paper focuses on solving the key problem in unmanned cars formation:following control problem of unmanned cars.A leader-follower model between two unmanned cars is established based on leader-follower mode.Considering the following situations may exist on the actual road:the following distance between this two unmanned cars is time-varying;the lateral and longitudinal synthetically following control is studied because of arbitrary curve motion of cars;the unsteady surface of the road causes the detection noise to the speed sensor of unmanned cars;the controller should be able to cope with the challenges of emergency brake of the leader under gusty conditions.By analyzing the following mode of two unmanned cars in the actual traffic scene,this paper builds the leader-follower model of two unmanned cars and designs controller which is invariant to disturbance,then realizes follower following the leader well in the above complicated working conditions.The main work of this paper is demonstrated as follows:Firstly,this paper analyzes the tracking problem of two unmanned cars in the actual road conditions.Following car follows leading car with the expected time-varying distance and angle.By introducing a middle body,the leader-follower model of two unmanned cars is established.The controller is designed by using linear feedback control algorithm which is simple and easy to implement,and the stability of the system is theoretically proved by using Lyapunov's second method.Matlab/Simulink simulation results show that the model established in the paper and linear feedback controller designed in the paper can achieve precise following control with expected time-varying distance and angle.Secondly,Matlab/Simulink simulation results show that control accuracy of linear feedback controller is poor in the case of detection noise and burst interference because of weak disturbance rejection ability of linear feedback control algorithm.This paper designs the sliding mode controller which structure is fixed and invariant to the disturbance handling the chattering by adding the filter algorithm into the sliding mode controller.The simulation results show that the sliding mode controller with filter can solve the problem of two unmanned cars follow control well with detection noise and burst interference respectively.Thirdly,considering that the chattering produced by the sliding mode controller cannot be fully processed,the paper further uses robust control algorithm to design a robust controller which has strong robustness to the disturbance.Matlab/Simulink simulation results show that the robust controller can solve the problem of following travel of two unmanned cars under complicated working conditions well,realizes that follower follows leader by expected time-varying distance and angle.The results of this paper are more closely related to the actual application of the unmanned cars formation...