The Fraunhofer Heinrich Hertz Institute has introduced a new measuring system with which the forces that occur during sailing can be determined precisely at any point on the sail. This makes it possible to measure and adjust the optimal trim for wind, water conditions, and any other factors that might arise, and to retrieve them at any time. The system is based on "fiber Bragg grating" (FBG) sensors that are recorded in optical fibers.
Fraunhofer HHI's sensor specialists record FBGs in standard optical fibers without damaging the fiber's surface. The advantage of this is that despite their thinness of only 0.25 mm - three times the width of a human hair - the optical fibers are very robust and stable. This means they can be either woven into the sails or fastened to them.
Through the motion of the sails during the way, the optical fibers and the grating of the fiber Bragg sensor are stretched and compressed. The light conducted through the optical fiber encounters the sensor's various structures, producing light waves of different lengths that the sensor measures. The resulting data is imaged by means of HHI-developed software on the onboard computer and transmitted via WLAN to a smart phone or iPod in the cabin. The data forms the basis for calculating the forces acting on the sail, and with this information, the optimal sail trim can be determined, adjusted, tuned and later retrieved.
The fiber-sensor technology for sailing has been developed in collaboration with the company "Segelwerkstatt Stade" and the sail manufacturer "Dimension Polyant". Initial test runs have been conducted in the North Sea.