Visualization Of 3D Scene Based On Chart Data And Grounding Alert

Shipping economy plays an important role in the world economy,and the ship is an important tool to develop the shipping economy.At the same time,the safety of ship navigation must be the first issue to be considered.In the total number of maritime accidents,ship grounding accidents account for a large proportion,and most of them are caused by human factors.Although the ship's officers can rely on the sounding instrument and other equipment as well as his own navigation experience to judge the grounding,this method sometimes can not give the grounding alert in time.Once grounding alert happens,the officers may not have enough time to avoid danger,which eventually leads to the ship grounding accident.In addition,in the case of fog navigation or night navigation,because the officers can not identify the relevant navigation mark in time,which leads to the occurrence of navigation accidents.In order to reduce the occurrence of these two kinds of maritime accidents effectively,this paper mainly studies the 3D(three-dimensional)scene visualization and ship grounding alert.The study of 3D scene visualization is divided into two parts,they are 3D scene visualization of navigation mark and 3D visualization of seabed terrain.The shape,color,top mark,luminous characteristics and other information of the navigation mark are extracted from the electronic chart data,and the corresponding navigation mark scene is automatically generated by using these information.The officers can conduct the corresponding maneuvering motion by identifying these navigation mark scenes,so as to ensure the safety of the ship in night navigation or fog navigation.The next step is the study of 3D seafloor visualization,by extracting the water depth data of chart and combining with Delaunay triangulation method,the irregular triangulation mesh is constructed,which can simulate the 3D seabed terrain better after adding texture.In addition,this paper studies the ship grounding alert,which can effectively solve the problem of the timeliness of grounding alert.This research is based on the 3D topographic map of the seabed.Then,by using the 3D topographic map and the effective grounding alert algorithm,the water depth angle is determined by collision detection method,and the ship grounding is judged after comparing with the danger alert angle.When the ship is sailing in the shallow water,the officers can make a timely decision and maneuver according to the alert.Through the use of these two aspects of research results,the ship can ultimately achieve the goal of ensuring the safety of navigation.