Design of Adaptive-Sliding Mode Controller for Positioning Control of Underwater Robotics

This paper presents a new robust controller for positioning control of underwater robotics. One of the most important underwater robotics that is used in navy and marine industries is underwater remotely operated vehicle (ROV). Control of ROV is not easy task, because of its dynamic. Various controllers have been proposed, such as sliding control, nonlinear control, adaptive control, and etc. Some nonlinear control schemes require an accurate system model of the ROV system. And some of control schemes require bound of parametric uncertainties. This paper is presented an adaptive-sliding mode controller that is focused on self-tuning when the control performance degrades during the operation due to model uncertainties and change in the vehicle system and its environment. The adaptive-sliding mode controller combined advantages of sliding mode controllers and adaptive estimators. In the adaptive-sliding mode controller, robust controller is applied for tracking and rejecting disturbances and adaptive estimator is applied for estimating uncertain parameters. This controller is compared with other control methods such as sliding mode controller. To show the validity of the proposed algorithm, computer simulation results are presented