ABSTRACT: In the given work the method of synthesis of the control law of vectored thruster AUV movement is offered. This control law allowing to provide its exact moving on the desirable trajectory in the conditions of limited capacity of its thruster complex. The given control system considers not only dynamic error, but also a deviation from the desirable trajectory, and desirable laws of trajectory movement. Besides, in work the algorithm of transformation of parameters of movement on a desirable trajectory is offered. This algorithm allows to consider indirectly capacity restrictions thruster complex and to change desirable movement parameters on a trajectory. INTRODUCTION Recently at performance of various underwater works (inspection of underwater communications, search and rescue works, etc.) the increasing value gets use of autonomous underwater vehicles (AUV). And in the course of performance of these works AUV should carry out difficult maneuvers, moving on the set spatial trajectory with the maximum velocity and accuracy. Use only one rotary thruster allows to provide the big autonomy of work, high velocity of movement at the expense of the streamline form of the case, and also high maneuverability on low speeds. However along with the specified essential advantages thruster complex of these AUV does not allow to form independently an thrusts and the moments on various degrees of freedom of AUV. The specified circumstance can lead to that at the high speed of movement on the desirable trajectory this AUV can deviate from this trajectory, because the part of power of the single thruster will be spent for creation of the moments of turn. The described problem can be solved at the expense of use of a special control system which would trace the given situation and corrected movement parameters on a trajectory.

ABSTRACT: In this paper, by dividing a multivariable system into single inputoutput systems by a decoupling technique and adding feedback control loops to each single input-output system, the author has tried to design an automatic control system to satisfy our specifications for control system design, as specified in the body of the paper. A rational and clear design of a multivariable control system is proposed. The fundamental characteristics of the control system are shown analytically, and examined by computer simulation. This control system combining decoupling and PI action feedback controls shows good tracking and disturbance control ability and is effective and useful during the approach and berthing maneuvers. INTRODUCTION Systems are generally multivariable, usually with coupling systems as shown in the top figure of Fig. 1. If the system can be divided so as to have an input-output relation of one-to-one correspondence as shown in the bottom figure of Fig. 1, it will be easier to design the control system. It is also important that the control system not only be able to perform the desired task, but that it also be able to compensate for disturbances. Ships are multivariable systems. Every input that is fed into a shipsystem has an effect on every output in the ship-system. Both functions must be factored into any control system. As an example, selecting the propeller and bow and stern thrusters as final control elements and ship speed, lateral shift displacement and heading angle as controlled variables, the author divides the multivariable system into three single input-output systems by use of a decoupling technique, and adds feedback control loops to each single input-output system. Furthermore, a rational and clear design method of the control system that satisfies our specifications for control system design is proposed.