Optimal Control of an Underwater Glider Vehicle

The aim of this paper is the trajectory control and navigation of an underwater autonomous mobile robot. The robot discussed in this paper is part of a new class of AUV's (Autonomous Underwater Vehicles) called underwater gliders. The underwater gliders stand out for replacing the thrusters for a mechanism of translation and rotation of internal masses and varying buoyancy, to move around. This new class of vehicles aims to overcome the problem of autonomy, found in other types of AUV's, due to limited battery life. The motion control is accomplished by the linearization of the non-linear model and applied the optimal control strategy known as LQR (Linear Quadratic Regulator). This strategy is applied to the robot control problem to track a reference and the robot control method effectiveness is verified by numerical simulations. The simulations show that the robot was capable to follow the path reference, in a maneuver of diving, in a short period of time. Thus demonstrating that the applied control method is a viable option, especially considering the need for battery saving since the method applied is optimal.