Vehicle Following Longitudinal Decentralized Feedback Control Based on Two-Time-Scale Motions

This paper is concerned with the problem of autonomous vehicle following control system design. Decentralized control scheme is used to provide the desired transient performances and spacing error given that an on-board equipment allows to measure the ego-vehicle´s relative position with respect to its preceding vehicle. The paper treats a question of controller design in presence of such uncertainties as mass of the vehicle, aerodynamic drag, and tire drag. The presented design methodology of continuous-time decentralized controller guarantees desired transients by inducing of two-time-scale motions in the closed-loop system. Stability conditions imposed on the fast and slow modes and sufficiently large mode separation rate between fast and slow modes can ensure that the full-order closed-loop autonomous vehicle following system achieves the desired properties in such a way that the transient performances are desired and insensitive to external disturbances and vehicle´s parameter variations. The method of singular perturbations is used throughout the paper. Numerical simulations for a three-vehicle platoon are presented.