Improving near-to-near lateral control of platoons without communication
Résumé
This paper considers the platooning problem: we aim to steer a train of vehicles along an unknown path generated by the first vehicle. Many approaches were developed in this field, but they present several drawbacks. On one side, centralised controls require communication between vehicles: communication failure will prevent the correct behaviour of the platoon. On the other side, decentralised controls usually propagate a lateral deviation which accumulates along the platoon; the path tracking is less and less precise as the follower is further of the leader, and the last vehicles may deviate and cut corners. The work presented in this paper proposes a decentralised local approach, to improve the platooning performance es- pecially in terms of tracking quality. Each robot uses its perceptions to compute the position of its preceding vehicle, which is memorized with those of previous time step to form a path. It then tends to follow this path instead of aiming the actual preceding vehicle's position. In other terms, the lateral controller will have as input a position on this path which is closer than the preceding vehicle's position. Experimentations were performed on Khepera III differen- tial wheeled robots. They highlight a drastic reduction of the lateral error in the platoon motion, comparing to the motion obtained with usual controllers.