This paper presents an adaptive path following control law to steer underactuated ships along a predefined path at a constant forward speed with uncertain parameters due to changes of added mass matrices.The proposed ...This paper presents an adaptive path following control law to steer underactuated ships along a predefined path at a constant forward speed with uncertain parameters due to changes of added mass matrices.The proposed controller is based on analytic model predictive control and model reference adaptive control.The SerretFrenet frame is used to describe the ship dynamics.The analytic model predictive control provides a systematic method rather than try-and-error method to get appropriate control parameters to guarantee the stability of the closed-loop system,and the well-defined relative degree is guaranteed by introducing output-redefinition.An identification algorithm based on model reference adaptive control is used to identify the uncertain parameters.Numerical simulations are provided to demonstrate the validity of the proposed control law.展开更多
A feedback-dominance based adaptive back-stepping(FDBAB) controller is designed to drive a container ship to follow a predefined path. In reality, current, wave and wind act on the ship and produce unwanted disturbanc...A feedback-dominance based adaptive back-stepping(FDBAB) controller is designed to drive a container ship to follow a predefined path. In reality, current, wave and wind act on the ship and produce unwanted disturbances to the ship control system.The FDBAB controller has to compensate for such disturbances and steer the ship to track the predefined(or desired) path. The difference between the actual and the desired path along which the ship is to sail is defined as the tracking error. The FDBAB controller is built on the tracking error model which is developed based on Serret-Frenet frame transformation(SFFT). In additional to being affected by external disturbances, the ship has more outputs than inputs(under-actuated), and is inherently nonlinear.The back-stepping controller in FDBAB is used to compensate the nonlinearity. The adaptive algorithms in FDBAB is employed to approximate disturbances. Lyapunov's direct method is used to prove the stability of the control system. The FDBAB controlled system is implemented in Matlab/Simulink. The simulation results verify the effectiveness of the controller in terms of successful path tracking and disturbance rejection.展开更多
基金Supported by the National Natural Science Foundation of China (Grant No.50779033)the National Hi-Tech Research and Development Program of China (863 program,Grant No.2007AA11Z250)+1 种基金China Postdoctoral Science Foundation (Grant No.20070420101)Shanghai Postdoctoral Scientific Program (Grant No.07R214128)
基金the National Natural Science Foundation of China (No. 50779033)the National High Technology Research and Development Program (863) of China (No. 2007AA11Z250)
文摘This paper presents an adaptive path following control law to steer underactuated ships along a predefined path at a constant forward speed with uncertain parameters due to changes of added mass matrices.The proposed controller is based on analytic model predictive control and model reference adaptive control.The SerretFrenet frame is used to describe the ship dynamics.The analytic model predictive control provides a systematic method rather than try-and-error method to get appropriate control parameters to guarantee the stability of the closed-loop system,and the well-defined relative degree is guaranteed by introducing output-redefinition.An identification algorithm based on model reference adaptive control is used to identify the uncertain parameters.Numerical simulations are provided to demonstrate the validity of the proposed control law.
文摘A feedback-dominance based adaptive back-stepping(FDBAB) controller is designed to drive a container ship to follow a predefined path. In reality, current, wave and wind act on the ship and produce unwanted disturbances to the ship control system.The FDBAB controller has to compensate for such disturbances and steer the ship to track the predefined(or desired) path. The difference between the actual and the desired path along which the ship is to sail is defined as the tracking error. The FDBAB controller is built on the tracking error model which is developed based on Serret-Frenet frame transformation(SFFT). In additional to being affected by external disturbances, the ship has more outputs than inputs(under-actuated), and is inherently nonlinear.The back-stepping controller in FDBAB is used to compensate the nonlinearity. The adaptive algorithms in FDBAB is employed to approximate disturbances. Lyapunov's direct method is used to prove the stability of the control system. The FDBAB controlled system is implemented in Matlab/Simulink. The simulation results verify the effectiveness of the controller in terms of successful path tracking and disturbance rejection.
