Stability of an automated vehicle platoon

Much attention has been focused on the development of automated highway systems (AHS), where the concept of automated vehicle platoons is crucially relied on. In the view of control an automated vehicle platoon can be regarded as an interconnected nonlinear system. Among a variety of issues involved in the design and operation of this system, the stability issue is of much concern both in theory and practice. The purpose of the paper is to derive some general conditions under which every intra-platoon vehicle is individually stable and the overall platoon is string stable. By considering stability properties of nonlinear systems with slowly varying inputs, we present two individual stability theorems for the intra-platoon vehicles and a string stability theorem for the whole platoon. It is demonstrated that a stable automated vehicle platoon can be achieved if the vehicular controllers are suitably designed