Adaptive and predictive control for off-road mobile robots path tracking

International audienceIf the development of algorithms dedicated for path tracking control of mobile robots is a well-known problem under the rolling without sliding condition (for vehicles moving on road for example), transfer of such control techniques are not always relevant for the case of mobile robots moving off road. Indeed, the application of control techniques developed under this assumption for off road vehicles demonstrates some unexpected behaviour, which depreciated considerably precision of a trajectory tracking (especially when vehicle executes a curve on a low adherent surface or when moving on a slope). Moreover, actuators used in natural environment are often more powerful and consequently less reactive, what introduces delays in vehicle dynamics. Such delays are emphasized by inertial effects, as the stability of off road vehicles requires the use of more important mass (and then inertia). An algorithm, taking into account for such phenomena and preserves the precision of path tracking for mobile robots, is presented. Capabilities of this approach are investigated through full-scale experiments, on farm tractor. Assistance of agricultural works indeed constitutes the application field of theoretical developments presented