Design of Miniaturized Fiber Optic Gyroscope Inertial Measurement Unit (IMU): High Precision, Low Power Solution

Discover the innovative design of a miniaturized Fiber Optic Gyroscope (FOG) IMU, offering high precision, low power consumption, and redundancy for aerospace, navigation, and industrial applications. Learn about its technical advantages and performance

1. Overview

With the increasing demand for inertial navigation systems in aerospace, high-end navigation, and industrial applications, miniaturization, low power consumption, and high reliability have become key indicators. This article presents an innovative design solution for a miniaturized Fiber Optic Gyroscope (FOG) IMU based on 40 years of FOG technology accumulation and verifies its excellent performance through engineering validation.

2. Technical Background

Fiber Optic Gyroscope (FOG) measures angular velocity using the Sagnac effect. Since its introduction in 1976, FOG has gradually replaced traditional mechanical and laser gyroscopes due to its solid-state structure, high reliability, and fast startup advantages.

3. System Architecture Design

This IMU system consists of two core components: the IMU module and the IMU circuit. The module includes four FOGs and four quartz flexure accelerometers, using a 4S structure. Any combination of three axes can achieve three-dimensional measurement of angular velocity and acceleration, with 1 degree of freedom redundancy to improve fault tolerance.
The circuit system includes the main/backup interface circuit and the power management module. The main/backup interface provides cold-hot backup and is responsible for acquiring sensor signals and communicating with the navigation system in addition to providing secondary power. The power management module independently controls the power on/off of each channel sensor, enhancing system integration and power regulation capabilities.

4. Core Device and Circuit Optimization

The miniaturized power management design utilizing LSMEU01 interface circuit based on SIP packaging and magnetic latching relays reduces the volume of the entire IMU circuit by approximately 50% and controls the weight to 0.778kg. The accelerometer adopts a temperature compensation strategy based on combined parameters, optimizing the power consumption of a single channel to 0.9W, effectively reducing the overall thermal load.
Performance Indicators
Total weight: 850g
Structure: Redundant configuration with 4 FOGs + 4 accelerometers
Application Environments: Aerospace, drilling surveying, dynamic communication platforms, and other scenarios with strict requirements on size, power, and performance.

5. Future Prospects

This design has completed integrated testing in multiple typical systems and demonstrates stable and reliable performance. As one of the smallest FOG IMUs on the market, U-F3X90 is suitable for applications such as Attitude and Heading Reference Systems (AHRS), flight control systems, inertial/satellite fusion navigation platforms, and high-dynamic industrial equipment. It provides a high-precision, low-power solution for various high-end applications.