Research On Key Technologies In Virtual Simulation System Of Marine Crane

Marine crane is a necessary and extremely important loading and unloading equipment on board ships.Its use can greatly facilitate the transport of goods in ports and ships.With the rapid development of international trade,the use of marine cranes in port and wharf transport more and more goods.The training methods of marine crane drivers have been plaguing many countries,and this problem directly restricts the rapid development of shipping industry.In this paper,the key technologies of marine crane driving training simulation system are studied,which mainly includes a six-degree-of-freedom platform for simulating the dynamic state of the cockpit of marine crane to simulate the real sloshing of the cockpit and a visual platform for simulating the real situation of the cockpit during the operation of marine crane.The main research work of this paper as follows:(1)Based on the theory of seakeeping and mathematical model of ship motion,the mathematical models of ship’s three degrees of freedom,namely roll,pitch and heave,are established.The wave inclination angle and wave surface equation of irregular waves are analyzed to obtain the disturbance forces and moments of rolling,pitching and heave.The program is programmed by MATLAB to solve the ship rolling equation and the pitching and heave equations.The rolling,pitching,floating and sinking angles and displacement curves of ships in irregular waves with different meaningful wave heights encountering upstream,oblique and rolling waves are simulated.(2)The three-dimensional model of marine crane is established by using Solidworks software.The three-dimensional model of marine crane is softened by ANSYS finite element software.The rigid region is delineated at the joint of lifting arm,tower body and base.It is guaranteed that the force can be transmitted when using ADAMS software for multi-body dynamics analysis.Using virtual prototype analysis software ADAMS to calculate the cab displacement data of marine crane when carrying cargo under the sea condition of 2 m and 4 m meaningful wave height,and to calculate and process the cab displacement data in some sudden situations.(3)A six-degree-of-freedom motion platform is selected to convert the six-degree-of-freedom displacement obtained by ADAMS into the cylinder elongation to simulate the real sloshing situation.(4)This paper studies the visual platform system in crane driving training,optimizes and renders the three-dimensional model of ship and marine crane by using 3D MAX software and imports it into Unity 3D.Finally,we use Unity 3D to model the external scene and build a virtual scene of sky,ocean,wharf,container and sun.The model of marine crane wire rope in Unity 3D is established by cable plug-in.A set of virtual simulation system is developed by using various functional components of programming language C#and Unity 3D.Through the computer control of each component of Unity 3D crane to complete various working conditions of the crane.