A unified force control approach to autonomous underwater manipulation

Abstract

A unified force control scheme for an autonomous underwater robotic system is proposed. This robotic system is composed of a six degree-of-freedom autonomous underwater vehicle (AUV) and a robotic arm that is mounted on the AUV. First, a dynamic model for the whole underwater manipulator system considering the hydrodynamic effects is derived. This model is then used to implement the proposed unified force control approach, which combines impedance control with hybrid position/force control by means of fuzzy switching to perform autonomous underwater manipulation. This approach combines the advantages of impedance control with hybrid control and has the potential to be effective in underwater environment. Extensive computer simulations are performed to verify the efficacy of the proposed control scheme, and the results are presented.