Adaptive and predictive control of a mobile robots fleet: Application to off-road formation regulation

Mobile robotics constitutes a promising way to reduce the environmental impact of agricultural activities while preserving the level of production to satisfy the growing population demand. In previous work, a formation control law, accurate despite typical off-road conditions (low grip, terrain irregularities, etc), based on a nonlinear observer-based adaptive control has been presented. Satisfactory advanced results have been reported in lateral servoing but inaccuracies in longitudinal regulation have been noticed. In this paper a new predictive approach dedicated to both longitudinal and lateral servoing is proposed. We consider mobile robots made of a single body accounting for bad grip conditions thanks to an observer based approach. After presenting the modelling of the formation and the control law use to maintain longitudinal and lateral deviations with respect to the reference trajectory, we introduce the predictive approach on velocity. Full-scale experiments demonstrate the performance of the proposed approach.