Redundancy resolution for underwater vehicle-manipulator systems with congruent gravity and buoyancy loading optimization

In this paper, a new redundancy resolution scheme is proposed for an underwater vehicle manipulator system (UVMS). Using the proposed resolution technique, the system´s redundancy is exploited so as to minimize gravity and buoyancy loading of the UVMS which is composed of subsystems with different dynamic responses. The generalized velocity components (GVC) approach is considered in order to obtain a congruent gravitational expression which consists not only of vehicle pose but also the onboard manipulator configuration. During end-effector motion, the overall system´s control effort is reduced if gravity and buoyancy loading of both subsystems are small values. A new performance index is applied using the local redundancy resolution. Results from simulations are presented to demonstrate the benefits of the proposed performance index.