Study And Realization Of Ship Collision Early-warning Sysetem In Bridge Waterways Based On AIS Data

With the development of China's economy and society,the status of water transport in the integrated transport system is more and more important.The ships in Yangtze River and other inland waterways tend to be with higher speed and larger scale,and the traffic density of ships is continuously increasing.At the same time,bridge construction on the Yangtze River,other major inland rivers and coastal waters are of rapid development.Which has different degrees of impact on the channel environment,the flow velocity and the flow direction,creating more disturbance in the bridge waters.The risk of ship-ship collision and ship-bridge collision is increasing,bringing different degrees of impact on the safety of human,ships,bridges,environment and the economic development.There is an urgent need to seek technical solutions to ensure the safety of ship navigation in bridge waters.In this study,we make the bridge waters in Wuhan Waterway as a specific study objects.Based on 126 million AIS data records,the dynamic model of the ship domain has been developed and analyzed,and the ship trajectory prediction method has been explored to develop the assessment model of ship collision risk.Based on the above work,the ship collision early-warning system has been designed and implemented.The main research contents are as follows:a)Based on the big AIS data,using statistical methods,the dynamic ship domain model has been analyzed.Considering the safety factors of navigation,the dynamic safety distance between ships in specific waters has been accurately described.Which provides the basis for the ship collision risk assessment and early-warning.b)Aiming at the shortcomings of DCPA and TCPA in collision risk assessment,based on the dynamic ship domain model,two new parameters for collision risk assessment are proposed from the perspectives of space and time.The practical methods for collision risk assessment and integrated collision risk model are given,and the risk assessment framework of ship collision has been constructed.c)Based on the comparative analysis of ship track prediction methods and the practical characteristics of ships' behavior in the bridge area,considering the accuracy and complexity of the algorithm,the third-order exponential smoothing algorithm has been used to predict the ships' position.Based on the prediction of ships' track in advance,ship collision risk has been assessed,offsetting the time cost of the network delay and data processing,and it is of great significance to the real-time early-warning.d)Based on the analysis of the functional requirements of ship collision earlywarning system,considering the general design principle,the early-warning criteria,early-warning flow,overall system structure,function module,system database and main interface of the system has been designed.Further,the main functions of the ship collision early-warning system has been realized.