Laboratory Evaluation of the Standard Elektrik Lorenz (SEL) Fibre-Optic Rate Gyroscope

A fibre-optic rate-sensing gyroscope (FOG) manufactured by Standard Elektrick Lorenz (SEL) was loaned to DREO for evaluation. The SEL FOG, model PMIDE, was designed for a drift rate of 10 to 100 deg/hr and consists of two units; a fibre-optic sensor and a support electronics unit. Laboratory tests were carried out in the DREO Inertial Navigation Laboratory and consisted of bias drift and scale factor over +/ 400 deg/sec as well as temperature sensitivity. Performance data obtained by DREO agreed closely with predicted performance although bias drift demonstrated wide deviations under thermal rate- transients. A permanent shift in bias drift and scale factor also occurred after extended testing at 50 deg C. A bias drift of 5.38 deg/hr +/- 0.68 deg/hr was achieved at 30 deg C and scale factor deviation was approximately 13,000 ppm over a rate range of 400 deg/sec. This instrument would be suitable for a low- performance Attitude and Heading Reference System (AHRS) application. Fibre- optic gyroscope, FOG, Rate sensor.