Design And Control Of Shore-assisted Berthing And Unberthing Equipment For Trimaran

With the continuous development of the ship industry,the requirements for the safety of ships are becoming higher and higher.The auxiliary berthing and unberthing technology is an important technology to improve the berthing and unberthing safety and efficiency when the ship berths.There are many safety and efficiency problems in the traditional auxiliary berthing and unberthing technology,which promotes the development of the auxiliary berthing and unberthing technology to be safer and more intelligent.In this design,an auxiliary berthing and unberthing device is designed to assist berthing and unberthing of a target trimaran.Due to the specialshape of a trimaran,traditional berthing and unberthing equipment may not work well,and an assisted equipment can significantly improve its berthing and unberthing processFirstly,the mechanical design of the shore-assisted berthing and disembarking equipment is carried out.According to the functions and the requirements of the assisted equipment,the motion degrees are determined.Moreover,the motion on each degree is discussed.In order to take consideration of flexibility,rationality and safety into the mechanical design,we can use SolidWorks software to model the three-dimensional work of trimaran and the assisted berthing and unberthing equipment and the finite element analysis is carried out for the assisted berthing and unberthing equipment.Secondly,the kinematic and dynamic model of the assisted berthing and unberthing equipment is established.Based on D-H modeling method,four important parameters of the linkage can be obtained,and the coordinate matrix of the terminal actuator,which is relative to the base coordinate system,can also be obtained by homogeneous transformation,so as to obtain the positive kinematics solution.While,the inverse kinematics of the equipment can be calculated by applying geometric method.By using Monte Carlo method on MATLAB simulation platform,the working space of the equipment can be illustrated.The Lagrange method is also used to calculate the dynamic model of the equipment.Thirdly,traditional PID control algorithm and fuzzy PID control algorithm are applied to control the assisted berthing and unberthing equipment.In order to verify the control algorithms,the docking progress is simulated on MATLAB/Simulink simulation platform.Finally,dynamic simulations are carried out by using the motion analysis tool of SolidWorks so that the relationship between the time and the displacement,speed and acceleration of the actuator at the end of the assisted berthing and unberthing equipment can be obtained.Using the animation tool of Solidworks,the grasping motion simulation of the target trimaran with the auxiliary berthing and unberthing device is carried out.