Testing and debugging of real equipment is a time consuming task. In particular, in the case of marine robots, it is necessary each time to carry out the transportation and deployment of a robot on the water. Experiments with not yet fully functional prototype of marine robot equipped with expensive hardware is in the meantime very risky. Therefore, the use of simulators is affordable way to accelerate the development of robotic systems from the viewpoint of labor effort and cost of experiments. This paper presents a simulator specifically designed for autonomous unmanned underwater vehicles.

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Abstract. In this paper authors develop and research system for motor boat control, that allows to move along the stated paths with the given speed. It is assumed, that boat is equipped by the measuring system that provides current coordinates, linear and angular velocities. Control system is based upon the mathematical model, presented earlier (see references). In order to analytically find the necessary controls, all equations were transformed to Jordan controllable form. Besides solution this transformation also allows to handle model nonlinearities and get required quality of movement along the stated paths. Control system includes algorithms for control of longtitudal velocity and boat course. Research of the proposed control system according to boat design limitations for the values of control variables was performed by simulation in MATLAB. Results of two experiments, different in value of the required velocity are discussed.

Abstract. Authors consider problem of maintenance and service of underwater vehicles. Usually, underwater station or accompanying ship is required for such operations. Docking is one of the most difficult tasks on the vehicle path from the outer space to the servicing bay. Algorithms allowing docking were presented in the earlier paper, and in this paper authors prove their stability. Movement control is based upon the path regulator. The stability of the closedloop system according to Liapunov with the given control and limitations is proven. Equations, showing that vehicle will complete the positioning task with account to given limitations and staying stable are given. The criterion for switching movement and "positioning to point" algorithms is proposed. Achievement of the developed criterion was researched theoretically and in computer simulation. Experiments provide deviation of actual coordinates and velocity from the required ones and proved that achieving of criterion is enough to claim that system will be stable while performing algorithms with limitations for controls.

When underwater vehicle need move from point A to point B during the completion of the mission it can be guided by the remote operator or move by itself. Both ways have pros and cons. For autonomous movement, control system needs a safe path that allows to pass the obstacles at the required speed. In previous papers authors already described the development of the control system, positionpath movement method, vehicle mathematical model, development of the hull and simulation results. Continuing this project, current paper is devoted to path planning module for the control system of the underwater vehicle. It briefly references the mathematical model, then describes position-path regulator. It is based upon PD law and implemented in discrete form with calculation of Dcomponent using trapezoid formula. Having control variables a yaw angle and longtitudal velocity, regulator outputs desired rotation speed of water screws. Path planning procedure consists of two steps. At first path is calculated on the basis of A*-algorithm using the known scene part. Then dynamic window method modifies the path so that UV moves at required velocity not passing the obstacles at unacceptable distance. Proposed approach was tested in Simulink app and proved to be efficient even in hard scenes with many obstacles. 