Task space-based control of an underwater robotic system for position keeping in ocean currents

Abstract

AbstractFor an underwater vehicle-manipulator system, which consists of an underwater vehicle equipped with a manipulator, it is important to regulate the position of the manipulator's end-effector with respect to a given target position in many interactive operations. This paper presents a task space-based approach for designing a controller that ensures that the end-effector of an underwater vehicle-manipulator system maintains its position in the presence of unknown ocean currents and uncertainties without the explicit use of a disturbance observer. A feedback linearizing control in task coordinates is used, and an extended Kalman filter (EKF) is employed as a state observer. The proposed approach can also be applied to dynamic positioning or controlled weathervaning of a surface ship whose motion is affected by environmental disturbances. To demonstrate the validity and effectiveness of the proposed approach, numerical simulations and experimental tests were carried out and their results are shown.Keywords: task space-based controlunderwater vehicle-manipulator systemdynamic positioningfeedback linearizing controlindirect adaptive control AcknowledgementsThis work was supported under the Korea-India Science Across Virtual Institute (SAVI) Program managed by National Research Foundation of Korea and partly supported by the Human Resources Development program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Trade, Industry and Energy.