Abstract
Nowadays, the purpose of the modern autopilot system is developing not only to keep a ship's course to the desired one but also to track the trajectory to make her navigate to the given line due to rapid development of global positioning system (GPS). The author's concerning has also changed to an automatic ship's guidance problem using a high speed computer and the GPS. This paper surveys the author's works on the first purpose of the autopilot system, ship's course keeping control one and also his recent researches on the ship's tracking or guidance problem including a ship's minimum time maneuvering problem and minimum time berthing one.
