Sliding Mode Control Of Driveway Keeping And Lane-Changing For Platoons

At present, there exist few studies concerning the work on the team control. If the modern control technologies can be used to a team, it has important significance to improve the current traffic pressure by coordinating and controlling the platoon to complete some complex tasks. The driveway keeping and lane-changing of team are the key technologies for completing some complex tasks. Therefore, the research about driveway keeping and lane-changing technologies of a team is necessary.The results of this paper are organized as follows:Firstly, the current study situation and the existing problems of the domestic and foreign intelligence transportation system are summarized. For the specific control tasks (for example, vertical and horizontal control, vertical and horizontal coupled control, lane keep, vehicle lane-changing for a vehicle, etc.), the used control technologies and control methods are summarized, and the advantages and disadvantages of them are pointed out.Secondly, for every vehicle of a platoon, the vehicle dynamical model with three degrees-of-freedom (i.e., lateral motion, longitudinal motion and yawing motion) is established by analyzing the forces of driving vehicle and Newton's second law. Based on such a vehicle model, the coupling between longitudinal and lateral orientations is analyzed. The control precision of a team is improved by considering the coupling between longitudinal land lateral orientations of a vehicle.Thirdly, the longitudinal and lateral control methods are designed respectively for the vehicle with the coupling between longitudinal land lateral orientations, and two control methods are coupling. Then the principle and advantages of sliding mode control are introduced, and a driveway keeping controller is designed according to the sliding mode control theory, and a simulation result is given to verify to realize that a team can drive in the prescribed path and maintain the given safe distance. Later, a lane-changing trajectory of a team is represented by a polynomial function and programmed, and a lane-changing controller is designed by using sliding mode control principle, so that the team can safely and accurately drive from the current lanes to the designated driveway; finally, a simulation result is given to verify the feasibility of this method. Due to that the lateral velocity of a vehicle may be no measurable, a lateral velocity observer is designed by taking the lateral error and lateral velocity (from a Preview point to the centerline of the road) as the state variables, which can obtain the estimate of lateral velocity.Finally, the work of this paper is summarized and the future work is prospected.