Underwater Towed Vehicle Manoeuvrable in Both Vertical and Horizontal Axis

Abstract

This paper proposes a new concept of guidance and control of underwater towed vehicle to perform operation in both vertical and horizontal axis with stable attitude.The control architecture of the vehicle has hierarchical structure consisting of attitude control, guidance, navigation, path planning and communication. CCV (Control Configured Vehicle) technology was adopted to perform the attitude control for the decoupling of motion.Two types of the attitude control in the vertical axis and in the horizontal axis are executed independently. Guidance is performed asynchronously with attitude control to give target values of the attitude control.Fuzzy algorithm was applied to determine the target values of the attitude control in the guidance process as well as to perform the decoupling of motion in the attitude control process.For four types of guidance, i. e. (i) horizontal movement survey, (ii) vertical movement survey, (iii) vertical and horizontal movement survey and (iv) seabed survey in vertical plane with constant altitude, control strategies were made. Target values for the attitude control and the effects of motion of towing mother ship in waves and tidal current were investigated through numerical simulations.