Statistic Study On LQG Control Method For Ship Lateral Motion Based On Parameters-fluctuating

By studying antirolling by rudder, many scholars find that the nondeterminacy of ship model widely affect the effect of antirolling method. It obviously shows that to design an antirolling controller with robustness is very necessary and whether we can eliminate the affection of that nondeterminacy or not will determine the future of the antirolling controller.The article tells us how to model for the robustness of ship lateral motion by hydrodynamic parameter perturbation method. When the hydrodynamic parameters of ship fluctuate around criterion value at random after the proportional distributing, the kalman estimation precise and relative controlling effect of LQG designing all will change. When a given ship navigates at the typical sea state, speed ,course and the hydrodynamic parameters of the ship fluctuate at random on the proportional distributing within a certain range, we work out the probability modeling of the kalman estimation and LQG designing for the ship.A large number of emulation results shows that when the hydrodynamic parameters of the ship fluctuate, the kalman estimation precise submits to logarithmic normal distribution and the controlling effect of LQG designing submits to normal distribution.