ROBUST GLOBALLY EXPONENTIALLY STABILIZING CONTROL LAW FOR FULLY ACTUATED 6-DOF AUVS

This work deals with the global exponential stabilization of the origin of 6- DOF AUVs. The control law is time-invariant and continuous. Unit quaternions are used as representation of orientation, preventing problems caused by the Euler singularity. No simplifications are made in kinematics or dynamics. A strict Lyapunov function is also developed for the controlled system. The system is proven to be ISS with respect to disturbances. This work also presents some highly useful results regarding unit quaternions, and presents a global diffeomorphism for position that eases controller design. Results are verified with simulations on the HUGIN 1000 AUV.