Miniature Inertial Measurement Units IMU200 and IMU400 Based on FOG with MEMS-Accelerometers: Development and Studying of Characteristics

Abstract

Nowadays interferometric fiber-optic gyroscopes (FOG, IFOG) are extensively used in strapdown INS, and in broad range of applications they have replaced their main competitor and predecessor - ring laser gyroscopes (RLG). To cover the new perspective applications with demands for low-cost and compact but precise inertial sensors, Optolink developed new products: most compact inertial measurement units IMU200 and IMU400. The aim of the current work was the development of pilot IMU200 devices and the estimation of the performance of IMU200 and IMU400 with direct measurements and also with SINS simulation methods. IMU200 SWaP properties are as follows: 75×75×60mm, <0.5kg, 1/3 l, ≤6W. The main IMU200 Gyro/Accelerometer accuracy parameters: Angle Random Walk (ARW) = 0.015°/√hour, Bias Instability (BI) = 0.02°/hour; Velocity Random Walk (VRW) = 40µg/√Hz, BI = 6µg. For IMU400, developed before IMU200, SWaP properties are: 80×95×62 mm, <0.7kg, ½ l, ≤7W. The main IMU400 accuracy parameters are: ARW = 0.007°/√hour, BI = 0.01°/h; Velocity Random Walk (VRW) = 40µg/√Hz, BI = 6µg. SINS expected performance (1σ, 10 min alignment time): for IMU200 heading 0.4°×sec(lat), for IMU400 ~ 0.2°×sec(lat).