Abstract
A new method to form feedforward inputs for underwater robot manipulators is proposed in this paper. In the proposed method, hydrodynamic torques such as added mass, drag and buoyancy in dynamics of underwater robots are obtained by time scale transformation and iterative learning control. The advantage of the proposed method is not to use parameter estimation of the dynamics. The results of the fundamental experiments with a single-link arm demonstrate validity of the iterative learning control in water and acquisition of the accurate hydrodynamic torques by time scale transformation for control.
