Total Stability in Adaptive Control for Path Tracking of Autonomous Underwater Vehicles

JORDAN, MARIO; BUSTAMANTE, JORGE

Bahía Blanca, Argentina

Jornada; V Jornadas Argentinas de Robótica (JAR 2008); 2008

Universidad Nacional del Sur

The work deals with the problem of adaptive path tracking of autonomous underwater vehicles with time-varying dynamics. The controller design is based on a modified speed-gradient adaptive law. A high-performance control behavior is aimed, so the full actuator dynamics is considered together with that of the vehicle. To this end, a state/disturbance observer is developed in the state feedback employing inverse dynamics. It is proved that the error paths can converge asymptotically to null when only the nonlinear static characteristic of thethrusters is involved in the design. When the actuator dynamics is considered too, only attractivity of the error paths to a residual set canbe stated. The framework for this last proof relies on the concept of totalstability. One main characteristic of our approach is that it can cope witha wide variety of bounded time-varying parameters with vanishing properties.