Automatic Identification System Ais Collision Avoidance System Implementation

In case of ship collision, the ship is seriously damaged, the goods are jeopardized, but the people are killed or horribly mutilated, and even the sea is extremely polluted. AIS can make the nearby ships and command platform grasp the static and dynamic information of all the neighbouring ship timely and call each other to coordinate immediately and take the necessary avoidance actions. However AIS has the following issues which have not yet been resolved: reduce or eliminate crashes caused by the human decision-making errors. Search its causes, it is obvious that the vast majority of crashes are due to the negligence and fault of mariners and serious violations of the rules for preventing collisions at sea.Development of ship's automatic collision avoidance system based on ship's automatic identification system,to a certain extent and scope,overcome the uncertainty of the collection of people and instability of process information and decision-making in the preventing collisions.According to the issues above, this article conduct a comprehensive and systematical study on the full process of ship collision avoidance, establishes mathematical models for the safety passing distance, the close quarters situation and the risk of ship collision, quantificationally plots out the ship encounter situations and collision avoidance actions for such situations, and discusses the time and range that the action should be taken and the time to resume its course. This article conducts an thorough research on the principles of ship collision avoidance, then utilizes the advantage of Automatic Identification System and the fruits achieved in quantitative investigation on ship collision avoidance . We proposes Genetic Algorithms to solve the ship collision avoidance problems. for making the search smarter, Combing with the Cascade Genetic Algorithms Model, we design a central monitor adjusting the sizes of these sub-populations dynamically and making the migration more directive the improved algorithms are denominated Extented Distributed Genetic Algorithms. We give the basic model and the process of Extented Distributed Genetic Algorithms, the details of each step of Extented Distributed Genetic Algorithms are analyzed.Extented Distributed Genetic Algorithms with real encoding, choosing the roulette wheel selection operator, assuring the best individuals participate in the crossover operator;choosing the uniform crossover operator, assuring the algorithms searching the whole defined space; choosing mutation operator based on real encoding, assuring the algorithms could skip the local minima;choosing dynamic migration operator, the sub-populations which have better evolutional ability will have larger space and more diversiform genes searching for optimization by absorbing the best individuals from other poorer sub-populations,making the evolvement of the whole population more directive.From the performance result, we can conclude that the preventing collisions simulation system set up in this paper is correct, and it is efficient to provide the decision-making scheme. By improving, the system can work as an assistant decision-making system.And it can provide important information for vessels' preventing collision decision-making.