High-precision inertial measurement unit IMU-5000

Abstract

Today interferometric fiber-optic gyroscopes (FOGs) reach ultimate theoretical performance and surpass well-established competitor, the ring laser gyroscopes. Due to its inherent low random noise and its scalability, FOG technology is one of the very few technologies able to cope with the applications requiring the highest performance. Recently, Optolink has presented new fiber-optic gyroscope SRS-5000 with bias performance, amongst the best closed loop fiber-optic gyroscope performance published to date. The aim of the current work was to produce and to estimate the performance of inertial measurement unit (IMU) and strapdown inertial navigation systems (SINS) pilot series on the basis of SRS-5000 FOG — IMU-5000 and SINS-5000, correspondingly. Measured device parameters (ARW around 0.000069 deg/Vh with a bias stability of better than 0.00008 deg/h) allow to assess these kind of devices as the highest-precision strategic grade fiber-optic gyroscopes' based IMU, commercially available. Pilot units of SINS-5000 show alignment accuracy limit down to RMS 0.005° in series of 9-minute alignments. Static tests show coordinates drift of ∼10 Nm over 7 days of operation. We believe the performance of these strategic-grade IMU and SINS may be useful in a range of high precision navigation, metrology, seismology, and structural sensing applications, as well as calibration of inertial test equipment.