China made 0.06 High Accuracy FOG north finder
1.1 Product Usage
Fiber optic gyroscope (FOG) north finder is mainly used to
determine the true north direction rapidly and independently. It
uses the two basic characteristics of gyroscope, i.e. precession
and axis-fixing, to realize the autonomous North finder. The
angular rate of the earth's rotation is obtained by high precision
FOG tracking. The angular rate signal of the earth's rotation is
calculated, and the angle between the main axis of the gyro and the
true north direction of the earth is calculated to provide azimuth
information for the carrier.
1.4 Key features
a) North finding time:≤3min;
b) North finding accuracy(1σ):≤0.06°(FNF701) ;≤0.1°(FNF702);
≤0.5°(FNF703)
c) Horizontal accuracy:≤0.1°
d) Weight:≤4.5kg
e) Power supply :24±4V;
f) Power consumption:25W(Peak value);
g) Interface:RS422;
h) Power-on preparation time 6 minutes;
i) Working mode: Self-check is started after power-up, and after
self-check is completed, it is controlled by the upper computer to
find the north. After the north-search is completed, the result of
north-search is sent to the upper computer.
1.5 Environmental Requirements
1) Working temperature:-40℃~+65℃;
2) Storage temperature:-45℃~+70℃.
3)Sand and Dust: Under the condition of sand and dust stipulated in
2 conditions of GJB150.12, the gyro north finder shall not appear
the following situations:
a. Institutions are too tight, stuck or malfunctioning;
b. Short circuit or abnormal operation of electrical components;
c. Dust in internal optical and mechanical parts.
4)Salt fog
The gyro north finder should meet the salt fog condition of
GJB150.11.
5)Hot and humid environment Conditions
Relative humidity: 95%; temperature: 30±2C; storage time 72 hours.
Insulation resistance should be no less than 2 MΩ_, metal surface
should not be rusted, coating should not appear foaming, spalling
and other phenomena, and can work normally.
6)vibration environment
Sinusoidal Scanning Vibration Environment Requirements
Frequency range: 5Hz ~ 5.5Hz, vibration displacement (dual
amplitude) 25.4mm
Frequency range :5.5Hz~200Hz,vibration acceleration 1.5g;
Scan time :12min;
Vibration direction:3 axises (X axis ,Y axis, Z axis );
Each axis:2h;
7)Impact Environmental Conditions
Shock Waveform: Semi-sinusoidal Pulse
Peak acceleration: 20g, pulse width 11ms,
Shocks times per axis (X axis , Y axis , Z axis ) is 3.
8)Collision Environment Conditions
Peak acceleration: 10g
Pulse width: 16ms
Collision Rate: Vertical Axis 80 times/min
Collisions times: 1000±10
Collision Direction: Vertical Installation Plane
Parameters | FNF701 | FNF702 | FNF703 |
Main technical parameters | North seeking accuracy (1σ) | ≤0.1° | ≤0.3° | ≤0.5° |
North seek time | ≤ 3min |
Horizontal accuracy (pitch and roll) | ≤0.05°(1σ) | ≤0.05°(1σ) | ≤0.05°(1σ) |
Power-on preparation time | 6min |
interface | RS422 |
Power supply | 24±4V |
Power consumption | 20w (peak) |
Weight | <3 |
Dimension | L120×W90×H115mm |
Working mode | After power on, it start self-test. After the self-test completed,
it will response to the upper computer’s north seek command. And
after north seeking, the north seeking result will be sent to upper
computer. |
Environment requirements | Operating temperature | -20 ~ +50℃ |
Storage temperature | -45~ +70℃ |
Relative humidity | 95% |
Appearance | The metal surface shall not be rusted, and the coating shall not
cause blistering or peeling. |
Electrical performance | Insulation resistance | The insulation resistance between the individual circuits of the
gyro north finder and its circuit and housing shall be not less
than 10 MΩ under standard atmospheric conditions. |
maintainability | MTBF | ≥1000hrs |
MTTR | ≤30min |