Disturbance Observer-Smith Predictor Compensation-Based Platoon Control with Estimation Deviation

Abstract

In the research of cooperative adaptive cruise control, the coupling relationship between the communication delay, the following time headway, and the string stability leads to a stringent limit on the minimum allowable following time headway. To deal with this limitation, this paper proposes the Disturbance Observer-Smith Predictor Compensation (DOB-SPC)-based Master-Slave architecture. The SPC is adopted to move the communication delays and actuator delays outside the feedback loop in the Master-Slave architecture. It theoretically realizes decoupling when parameters are estimated accurately and achieves zero-headway-string-stability for arbitrary values of communication delay. Subsequently, the robust performance of SPC with estimation deviation of vehicle model dynamic lag, actuator delay, and communication delay in practical application is discussed through the changing trend of the minimum string-stable time headway. To alleviate this problem, the DOB is designed to compensate for the interference caused by the perturbation of vehicle dynamic parameters and improve the estimation accuracy. The simulation results of a four-vehicular platoon show that the string stability and following accuracy are fully guaranteed by applying the proposed strategy, even with smaller headway in the presence of estimation deviation.