String stability and a delay-based spacing policy for vehicle platoons subject to disturbances
For researchers in vehicle platoon control, this work addresses the challenge of maintaining stability under external disturbances and varying reference velocities, though it is an incremental extension of existing spacing policies.
The paper introduces a delay-based spacing policy for vehicle platoons that ensures all vehicles track a spatially varying reference velocity, and defines disturbance string stability to prevent unbounded growth of perturbations. Simulations demonstrate the approach's effectiveness.
A novel delay-based spacing policy for the control of vehicle platoons is introduced together with a notion of disturbance string stability. The delay-based spacing policy specifies the desired inter-vehicular distance between vehicles and guarantees that all vehicles track the same spatially varying reference velocity profile, as is for example required for heavy-duty vehicles driving over hilly terrain. Disturbance string stability is a notion of string stability of vehicle platoons subject to external disturbances on all vehicles that guarantees that perturbations do not grow unbounded as they propagate through the platoon. Specifically, a control design approach in the spatial domain is presented that achieves tracking of the desired spacing policy and guarantees disturbance string stability with respect to a spatially varying reference velocity. The results are illustrated by means of simulations.