Research On Track Control And Development On Manipulation Interface For Dynamic Positioning Ships

Nowadays, people's research about the ocean is going into the blue water. The need for the high performance dynamic positioning system (DPS) is becoming more and more exigent. For this reason, researchers are continuously making great efforts to study new techniques to meet the demand in both civil and military field. As an important function in DPS—track-keeping, the required performance standard for it is becoming higher and higher. The main contribution of this dissertation is a method for better performance in both high speed and low speed ship trajectory control, by developing a new track-keeping controller. Beside this, the dissertation also gives a new method for the design of a DPS manipulation interface which can run under the Windows OS.Low speed track-keeping function is aim at keeping ship moving accurately along the set ship trajectory under low speed condition. But normally, common method can't fulfil the required control accuracy. This dissertation gives a new method and the corresponding algorithm which is useful under the low speed condition, it change the track-keeping to the positioning finding and the direction finding. In order to solve the track-switch problem between two segments of the ship trajectory, here gives two track-switch strategies. Based on one DP ship model, this dissertation designed a parameter adaptive fuzzy-PID surge\sway controller and an improved PID heading controller. According to the control effects under different simulation conditions, the control method can be proved useful and fulfills the requirements. Meanwhile, by contrasting the efforts between two track-switch strategies, a better one was selected.High speed track-keeping function requires the ship to moving accurately along the set ship trajectory with the cruising speed. By using indirect control method, a cascade controller which is based on the parameter adaptive Fuzzy-PID was proposed. The special point of this controller is to use the speed as an input of the fuzzy decision-making. Also, a control method which ensures a smooth process during the tack-switch is proposed. The simulation control results show that this high speed track-keeping controller can fulfill the requirements. It also has a strong robustness and good stability.In domestic, for a long time the development of the DPS operation system is usually based on the DOS OS. Differently, this dissertation uses the Visual C++ platform and the object-oriented programming method to design a DPS interface which can run under the Windows OS. By using memory plot,serial port communication etc, the software system has a better visualization and flexible expansibility character.