The vessel is controlled on the basis of positional information from position reference system. As with the position, the deviation of heading smaller between heading data from Gyro compass and set one.
(2) Auto tracking mode;
The vessel is navigated automatically along the given course keeping her speed at the given one. When she approached a waypoint, she turns using the rudder and change to the next course, tracing an inscribed circle of Tank test An example of display screen for tracking control (LCD) the waypoint. According to her speed, the thruster is used.
(3) Auto heading mode;
In this mode, the vessel's heading is automatically maintained and controlled to make the deviation smaller between the heading data from Gyro compass and the given one. Wind force as external force is estimated and compensated on the basis of Anemometer's data.
(4) Other functions;
About other control functions, for example, there is the manual joystick mode, individual control mode, standby mode and so on. In the manual joystick mode, the vessel's position, heading and speed are controlled manually using the joystick and turning round dial. In the individual control mode, propeller pitch angle and rudder angle is controlled with the joystick and turning round dial standby mode has a function, which transmits a neutral command to each actuator.
4. Improved Position Keeping Accuracy
The new type DPS inherits the echo sounder from the conventional one, and replaces the electronic position finder with a GPS to improve the accuracy of positioning. In addition, the differential GPS (DGPS) is used, it becomes be able to improve the position keeping accuracy.
5. Enhanced Redundancy
The control board consists of two functional equivalent control units and a monitoring unit for monitoring the results of their computation.
While the two units simultaneously perform control computation, if any abnormality occurs in the selected control unit, the operator can confirm the warning, and change over the control line to the other normal control unit.
6. Increased Reliability
Before sea trial, the trainee is given an opportunity to simulate ship motions with a simulator and set various control gains. Then, he finalizes the control gains at sea.
In architecting the simulator, a ship model is produced, and carry out wind tunnel tests for static air force measurement.
Additionally, PMM tests fulfilled to determine the hydro-dynamic coefficients, which are reflected in estimating the hydro-dynamic forces for numerical simulation.
