Motion control of Underwater Robot based on an improved controller

Researches are undertaken to improve the control effect of Underwater Robots. A capacitor plate model controller (CPMC) is designed for a certain type of Underwater Robot. A new control method: generalized S-plane controller (GSPC) is put forward based on the analysis of two new control methods, sigmoid S-plane control (SSPC) and capacitor plate model control. Generalized S-plane controller represents the essence of fuzzy control and has simple structure of PD control. Compared with fuzzy control, it fractionizes fuzzy rules, decreases the complexity when adjusting parameters and reduces the calculation. The two methods are applied to the Underwater Robots´ simulation experiments and sea trials and plenty of results are obtained. The analysis of the results tells that when setting the same parameters, choosing a nonlinear S-model function with better astringency to substitute the sigmoid function used in sigmoid S-plane control, better results can be achieved. The validity of the proposed new controller is verified and it has some practical engineering values.