Adaptive Iterative Sliding Mode Control Of Twin-rudder Twin-propeller Ship Course/Path Tracking

With the rapid development of the world economy,economic globalization has greatly promoted the international economic exchanges.Container ships as carrier of sea transport become increasingly busy.Although since the 2008 financial crisis,the shipping industry has some downturn,large,especially super-large container ships can effectively reduce the cost of single-box transport,so large-scale,high-speed development is the main trend.The Maersk Triple E with twin-rudder twin-propeller system achieves 18000 TEU,which has energy-saving,eco-friendly and economical features.In recent years,the requirements of ship automation have been gradually raised.It is of great significance and value to study the motion control of twin-rudder twin-propeller ship.Firstly,based on the MMG model theory,this paper establishes the twin-rudder twin-propeller and the interference model of wind,waves and currents model.The 18000TEU Maersk Triple E is used as the research object,and the maneuverability simulation experiment is carried out and compared with the real ship data.Secondly,this paper studies the course tracking of twin-rudder twin-propeller ship under the ocean navigation condition.Aiming at the uncertainty of model and external disturbance,a nonlinear iterative sliding mode control algorithm is designed to avoid estimating the system uncertainties and unknown interference,reduce the dependence on accurate model and suppress chattering.At the same time,based on the iterative sliding mode algorithm,the neural network is introduced to enhance the adaptability of the controller,optimize the parameters and speed up the response.Then,in consideration of current interference,etc.,the research on straight-path following control of twin-rudder twin-propeller ship is studied.Nonlinear iterative sliding mode control algorithm is used to stabilize the lateral deviation of the ship.And the neural network is used to optimize the controller parameters to improve the tracking performance of twin-rudder twin-propeller ship,enhance the robustness and analyze the influence of ocean current on navigation.Finally,The Matlab software is used to study the course tracking and straight-path following simulation of Maersk Triple E ship.The simulation results show that the controller designed in this paper can effectively deal with the external disturbances and the uncertainty of the model,which can achieve the expected target,and more in line with the actual operation of the ship.