High Precision Fiber Optic North Finder for Accurate True North Determination

Fiber Optic Gyroscope (FOG) North Finder is a high-precision device designed for rapid, autonomous determination of true north. By detecting the Earth’s rotation angular rate through a FOG and resolving it into directional components, the system accurately calculates the azimuth between the gyroscope’s main axis and geographic north.
The unit integrates a fiber optic gyroscope, accelerometer, rotation control mechanism, and embedded computer, forming a compact electromechanical system. With a north-seeking time ≤3 min and accuracy up to 0.3° (1σ), it provides reliable azimuth and attitude information for vehicles, ships, and other mobile platforms.
Operating from -40 °C to +70 °C, powered by DC 12–24 V, and communicating via RS-422, the lightweight (≤2 kg) FOG North Finder ensures fast startup, automatic self-test, and robust north-seeking performance even in harsh environments.

1.1 Overall dimensions

Dimension (mm): 115 × 90 × 110

1.2 Main technical indicators

A) North seeking time: ≤ 3 min;

B) North seeking accuracy (1σ): ≤ 0.3 ° (NF701A); ≤ 0.5 ° (NF701B)

C) Horizontal accuracy: ≤ 0.05 ° (1σ);

D) Circumference: ≤ 0.5 ° (1σ)

E) Weight: ≤ 2 kg;

F) Power supply: DC 12V ~ 24V;

G) Power consumption: 15 W (peak);

H) Interface: RS422

I) Working mode: start automatic self-check after power on, control north seeking by the upper computer, and send north seeking results to the upper computer after north seeking is completed;

1.3 Environmental requirements

1) Working temperature: -40 ℃ ~ + 70 ℃;

2) Storage temperature: -55 ℃ ~ + 85 ℃.

3) Humid and hot environmental conditions: relative humidity is less than 95%.

4) Appearance: The metal surface shall be free of rust, and the coating shall be free of blistering, peeling, etc.

1.4 Electrical performance

Insulation resistance: the insulation resistance between the independent circuits of the fiber optic gyroscope north finder and between the circuit and the shell shall not be less than 10 MΩ under standard atmospheric conditions.

1.5 Reliability and maintainability

MTBF ≥ 1000 hours;

MTTR ≤30min.

1.6 External interface

1.6.1 With DC12 V ~ 24V power input.

1.6.2 With serial port output function.

1.8.3 External plug:

Interface Y50EX-0607TX2, see the table below for pin definition.