The heel and trim adjustment of manned underwater vehicle based on variable universe fuzzy S surface control

Manned underwater vehicle plays a significant role in underwater rescue. The key of this process is the docking between manned underwater vehicle and disable submarine within a certain angle. That means manned underwater vehicle has to have good maneuverability, especially the maneuverability of trim and heel. Ballast water system is a simple and effective way for the adjustment of trim and heel. It can also simplify the thrust allocation processing. Variable universe fuzzy S surface control method is adopted to control the ballast water system. This method is applicable not only to control nonlinear motion model such as manned underwater vehicle, but also to achieve on-line setting of the control parameters according to the relevant theories and experience. The experiment results show that the control effect of this system is ideal and its robustness is strong in the case of a flow disturbance.