Adaptive DOB control of underwater robotic vehicles

Abstract

This paper describes a new navigation control system for AUVs. Unlike controllers for ROVs, AUVs require smart controllers adapting to changes in the system and environment since the controller cannot be tuned while AUV are in water. The presented controller consists of a nonregressor based adaptive controller and a disturbance observer (DOB). The DOB converts the original nonlinear vehicle dynamics with modelling errors and disturbance into a simple linear nominal model and the adaptive controller compensates for the residual disturbance errors due to any time delay in the DOB filter. The presented control system does not require any parametric information about the vehicle dynamics and provides robustness with respect to disturbance, such as current, modeling errors and hydrodynamic uncertainties. Results of simulation on a UH AUV, ODIN model show effectiveness of the presented control system.