비선형 추진기 모델을 사용한 HAUV의 한계싸이클 거동 시뮬레이션

Abstract

Most nonlinear dynamic systems show limit cycle behaviors. limit cycle behavior is a permanent output oscillation in the amplitude and frequency that are independent from input signals. Therefore, the limit cycle behavior causes detrimental effects on marine vehicle maneuver fir the underwater vehicle maneuver in the observation and docking motions, which require accarute position controls. In this paper, 'Describing Function method' was used to analyze the limit cycle behavior. This Method is a convenient tool to derive a quasi-transfer function of a nonlinear system. A limit cycle behavior of HAUV with a nonlinear thruster model was simulated to figure out the effect of nonlinear thruster dynamic on the HAUV motion control. Traditional P-, PD- and PID-controller were applied to observe the effects of the limit cycle behavior on each controller. Simulation using MATLAB/SIMULINK showed the nonlinear thruster systemdominated the response of HAUV motion control and cause a limit cycle behavior. In controller simulations, the PD controller showed better performance the the PID controller.