Simulation and analysis of maritime traffic in the Tagus River Estuary using AIS data

Simulation models of ship navigation can be a powerful tool for marine traffic risk assessments, which are important for ships transiting in narrow, shallow and busy waterways. In this paper a model of ship navigation in restricted waters and the Monte Carlo simulation technique are used to simulate marine traffic based on AIS (Automatic Identification System) data. The simulation model consists of a ship collision avoidance model based on the Artificial Potential Field (APF) method, which is an effective and practical method for finding a safe way for ships. AIS data is first analysed in detail to obtain the main characteristic of traffic parameters used as input of the traffic simulation model, such as: the main vessels' trajectories, speed distribution of the vessels, traffic density, among others. The algorithm of the APF method is implemented and applied to simulate the traffic in the Tagus River Estuary based on AIS data of ships entering and leaving the port of Lisbon.