On disturbance propagation in vehicle platoon control systems

This paper considers the problem of disturbance propagation in a vehicle platoon control system, where each vehicle has access to its position error relative to the preceding vehicle in the string. It is known that in such systems a small disturbance acting on one member can propagate downstream and cause large spacing errors between vehicles. A lower bound to the integral of the sensitivity function of the position errors with respect to a stochastic disturbance acting on the lead vehicle is presented. The tightness of the lower bound is discussed and numerical evaluations are provided to illustrate how this result can assist in practical controller design.