A LONGITUDINAL CONTROL SYSTEM FOR A PLATOON OF VEHICLES USING A FUZZY-SLIDING MODE ALGORITHM

Recently much interest has been concentrated on the development of intelligent vehicle highway systems (IVHS) since they are considered to have the ability to effectively handle the traffic problems of the current industrialized society. In this context, this paper presents a control algorithm for a platoon of vehicles, which is one of the most important research areas of IVHS. The suggested control algorithm consists of a headway controller and a velocity/acceleration controller. The headway distance to the preceding vehicle and its changing rate along with the velocity of the leading vehicle are used to derive the headway control laws without using headway information from other vehicles. The velocity/acceleration controller, which controls the throttle and the brake of the controlled vehicle according to commands from the headway controller, is designed by using a fuzzy-sliding mode control (FSMC) algorithm, which does not require exact models of vehicles. It is shown that the proposed control algorithm guarantees string stability under several conditions even when each vehicle has different performance. The good performance of the suggested control algorithm is illustrated by simulations and road tests in which vehicles follow one another at 10-m spacings at a peak velocity of 80 km/h.