Research On Intelligent Decision Of Single-ship Collision Avoidance In Open Waters

With increasing of the traffic density at sea in recent years, ship collision accidents occur frequently,80%of which are caused by human factors according to the survey. In order to solve the problem of ship collision caused by human factors, many experts and scholars have carried out extensive research and done a lot of work about ship automatic collision avoidance decision-making system, and gotten some achievement, but so far no mature and practical system has been achieved. Research on ship automatic collision avoidance system becomes the main direction of navigational technology areas in the next ten years.In this paper, a ship course controller is designed for automatic collision avoidance based on intensive study on ship collision avoidance decision-making process.Firstly, this paper studies and optimizes mathematical models involved in the process of ship collision avoidance, these models include:the model of calculating basic parameter (the calculation of DCPA, TCPA and SDA), the model of dividing encounter situation, the model of close-quarters situation (to get the D1), the model of collision risk evaluation between vessels (considering the space collision risk and time collision risk), the model of recovering course and so on. Secondly, considering the characteristics of the rudder and the rudder angle limitation, this paper designs a.ship course controller based on Backstepping. This controller can judge encounter situation according to different directions of the coming vessels and can determine the action time and action amplitude automatically, so it can achieve the collision avoidance action automatically. Thirdly, this paper makes automatic collision avoidance simulation for different encounter situations with MATLAB, and the simulation results show that the ship course controller designed in this paper is effective, which lays a foundation for the application.In this paper, the object of research is the situation of two vessels in open sea-room which is the most basic encounter situation, and therefore the collision avoidance decision-making system designed in this paper is a basic branch of the ship automatic collision avoidance system. The research findings in this paper lays a foundation for collision avoidance study in multi-ship encounter and narrow waters.