Design of Platooning Controllers That Achieve Collision Avoidance by External Positivity

Abstract

This paper solves the problem of designing local adaptive cruise controllers that guarantee collision avoidance of the vehicles in a platoon. Whereas previous studies have solved this problem for specific vehicle models, the present paper shows a general solution for a wider class of linear vehicle models. In particular, the problem of finding a controller that renders a vehicle externally positive to guarantee string stability and collision avoidance is studied in detail. The result is an algorithm that finds a set of closed-loop eigenvalues that correspond to an externally positive feedback loop. The developed methods are applied to an example and the effectiveness is verified in a laboratory experiment with multiple robots driving in a platoon.