Simulation Of Ship Maneuvering Training Environment Based On WebGL And WebSocket

The maneuverability of the crew is very important to ensure the safety of maritime navigation,so it must be a top priority to improve the maneuverability of the crew through training.Domestic use of VR(Virtual Reality)technology or simulation technology realistically reproduce the three-dimensional system environment,training personnel can ground of ship navigation manipulation training,in a short period of time to achieve the ideal and effective training effect,but due to the big high cost,long development cycle system,poor scalability,and fixed venues,the number of trainees and the duration of training are limited,these weaknesses are difficult to ensure that the trainees have enough training time.With the advent of HTML5 and the widespread use of JavaScript virtual engine and the improvement of perf-ormance,the web-based ship simulation training system is gradually developed,which allows multiple users to conduct ship manipulation training anytime and anywhere.However,heavy and cumbersome installation of browser plug-ins is a drawback of Web rendering,which not only limits the portability of the model,but also hinders maintenance and update.The emergence of WebGL(Web Graphic Library)technology solves the shortcomings of plug-in installation and poor portability.It can be used to create realistic 3d scenes directly.WebSocket communication protocol to appear at the same time,realize the two-way connection between the browser and server side,not only the browser can transmit data to the server,the server can push data to the browser end,make the data exchange between the client and server browser become more simple,avoid the traditional polling,Ajax polling and other traditional way transmission bandwidth rate high,shortcomings and so on server is unable to take the initiative to transfer data,to meet the ship maneuvering training requirements for real-time data transmission.In this paper,considering WebGL and WebSocket,a ship handling training system based on B/S(Browser/Server)architecture is built.WebGL technology is used to render the 3d scene of ship manipulation training,and WebSocket protocol is used to realize the real-time interaction of ship manipulation training information,which provides a collaborative and realistic environment that is not limited by time and space for ship manipulation training of multiple crew members,and effectively improves the training level of crew members.The main research work includes the following:1)The frame design of ship control training systemThe system adopts B/S architecture,the database uses MySQL database to store the logged-in user information,port data and ship information;the server uses the Spring Boot framework to build the server to complete the mathematical model solution;CSS completes interface design,mainly including ship static information area,ship dynamic information area and ship maneuvering control area.2)3D scene rendering of ship maneuvering training environment based on WebGLUsing WebGL technology to realize the three-dimensional simulation of the ship's maneuvering training environment on the web,including the visualization of the sea surface,near-shore terrain,islands,and navigation aids.Three-dimensional visualization of ships sailing on the sea,including weather simulation of rain,snow and so on.3)Real-time data interaction of ship operating environment based on WebSocketprotocolUsing WebSocket protocol as a data transmission channel,to implement the Web control of the ship to the server to send information,the server side pushes the practice environment information,the position and attitude of all ships,and other navigation environment information to all the Web side in the training,at last,through experiment has network delay problems,then on the basis of this puts forward the improved method based on time compensation.