Fanbeam / Cyscan

A technical blip this time; right now we are positioned motionless - within 5 meters distance - alongside the Hermod with a bunkerhose connected. How? Because our indefatigable DP system is keeping us there with a decimeter accuracy. To establish that position, we use DGPS which stands for Differential Global Positioning System. But what if that signal would fail? We need a back-up and that back-up is called fanbeam. It is transmitter on top of our wheelhouse transmitting a laser signal to a reflector on the Hermod and back. As soon as we confirm that this is the correct reflector, the system locks and determines a bearing and distance. The computer gives the thrusters orders to keep this bearing and distance exactly the same, so no postion shift relative to the Hermod is possible. We only use it if we have problems with our GPS reception, because GPS is a true reference system and fanbeam a relative system. On this picture you'll see that the reflector is placed at a distance of 50 meters on our PS stern with a bearing of 216 degrees true. You can also see that this reflector is placed higher than our transmitter, because the tilting angle is 8 degrees.