3.2. Tanker Track Keeping
Track Keeping is different from Course Changing in that the tanker follows the commands of an autopilot rather than the step commands of a pilot. In this context an autopilot is a system which automatically determines the heading that a vessel should follow in order to stay on course. It does this by taking vehicle position information and using it to calculate heading corrections so that the vessel follows a predetermined course, which is set prior to autopilot activation. The particular autopilot studied here is called a line-of-sight (LOS) autopilot ( Fossen, 1994; Healey & Lienard, 1993)