Research On Ship Path Planning Considering Marine Environmental Risk

Marine transportation is the most important mode of transportation in international logistics,and it is also an important pillar to ensure the prosperity of national economy and the prosperity of the people.Marine transportation has a large carrying capacity and low freight,but it has a long sailing period and great risk,so it is of great significance to ensure the safety of ship navigation.When ships are sailing in the sea,wind,wave,current and other natural environmental factors are complex and changeable,which seriously threaten the navigation safety of ships.Therefore,in order to minimize the loss of ship personnel and property,it is particularly necessary to study the ship path planning considering the marine environmental risk.Based on the marine environmental data,the marine environmental risk field is constructed in the Malacca Strait and its adjacent waters.According to the different planning requirements of ships,the improved ant colony algorithm is applied to the research of ship path planning in the waterway network,and the ship path planning under multiple constraints is realized.At the same time,aiming at the complex and changeable marine environmental risks,the improved artificial fish swarm algorithm is applied to the research of ship path planning in the grid map,and the dynamic path planning of ships in different risk areas is realized.The main research work is as follows:(1)The marine environmental risk field model based on generalized network analysis method is constructed.Through the analysis of the natural environmental factors in the study area,four factors are selected,including terrain,sea wind,wave and current,and single factor risk measurement is carried out for these factors.At the same time,the generalized network analysis method is used to determine the index weight of each factor,and the spatial analysis method is used to build the marine environmental risk field model.(2)The global path planning based on improved ant colony algorithm is realized.According to the principle of referring to the historical track in ship path planning,the method of extracting the channel center line based on image processing is used to construct the waterway network.According to the different planning objectives of ships,the ant colony algorithm is improved in node selection and pheromone update,so that the algorithm can realize the path planning under multiple constraints in the waterway network.According to the experiments,the path planning method based on the improved ant colony algorithm can realize the path planning under the constraints of water depth,specific port,path length and path risk.(3)Local path planning based on improved artificial fish swarm algorithm is realized.Aiming at the problems of falling into local optimum and long path in traditional artificial fish swarm algorithm,this paper improves the algorithm in walking mode and field of vision.The experimental results show that the path planned by the improved algorithm can not only avoid the coast,islands and high-risk areas,but also reach the destination with shorter distance and less risk.At the same time,in order to study the impact of different target weights in different risk areas on ship path planning,the appropriate target weights are selected in each risk level area,and the dynamic weight path planning method is realized.Experiments show that the dynamic weight path planning method can achieve dynamic path planning in low risk,medium risk and high risk areas.