Fibre optic gyroscope 1958422 215492305 2008-05-28T13:04:47Z Spiel496 881080 [[WP:UNDO|Undid]] revision 215452545 by [[Special:Contributions/59.96.147.134|59.96.147.134]] ([[User talk:59.96.147.134|talk]]) <!-- Image with unknown copyright status removed: [[Image:Fiber_Optic_Gyro.PNG|thumb|]] --> A '''fibre optic gyroscope''' (FOG) is a [[gyroscope]] that uses the [[interference]] of light to detect mechanical rotation. The sensor is a coil of as much as 5 km of [[optical fiber]]. Two light beams travel along the fiber in opposite directions. Due to the [[Sagnac effect]], the beam traveling against the rotation experiences a slightly shorter path than the other beam. The resulting [[Phase (waves)|phase shift]] affects how the beams interfere with each other when they are combined. The intensity of the combined beam then depends on the rotation rate of the device. A FOG provides extremely precise rotational rate information, in part because of its lack of cross-axis sensitivity to vibration, acceleration, and shock. Unlike the classic spinning-mass gyroscope, the FOG has virtually no moving parts and no inertial resistance to movement. The FOG typically shows a higher resolution than a [[ring laser gyroscope]] but also a higher drift and worse scale factor performance. It is used in surveying, stabilization and inertial navigation tasks. FOGs are designed in both [[open-loop]] and [[closed-loop]] configurations. ==See also== * [[Inertial Measurement Unit]] * [[Vibrating structure gyroscope]] * [[Quantum gyroscope]] * [[KVH Industries]], a manufacturer of Fibre Optic Gyroscopes. * [[Ring laser gyroscope]] ==References== * Anthony Lawrence, ''Modern Inertial Technology: Navigation, Guidance, and Control'', Springer, Chapters 11 and 12 (pages 169-207), 1998. ISBN 0387985077. * G.A. Pavlath, "Fiber-optic gyroscopes", IEEE Lasers and Electro-Optics Society (LEOS) Annual Meeting, 1994. LEOS '94 Conference Proceedings, Volume 2, pages 237-238. 31 Oct-3 Nov 1994. ==External links== *[http://leoss.feri.uni-mb.si/dip_vedran.html Good diagram from the University of Maribor] *[http://www.sagem-ds.com/eng/site.php?spage=02010301 Sagem Défense Sécurité website] [[de:Faserkreisel]] [[es:Giróscopo de fibra óptica]] [[he:גירוסקופ סיב אופטי]] [[nl:Fibre optic gyrokompas]] [[Category:Gyroscopes]] [[Category:Fiber optics|Gyroscope]]