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Phone: 0510-83880511
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Main characteristics：1. Introduction The NF100 small volume fiber optic gyroscope north finder is mainly composed of fiber optic gyroscope, accelerometer, mechanical rotating device, and signal solving circuit. By ut
1. Introduction
The NF100 small volume fiber optic gyroscope north finder is mainly composed of fiber optic gyroscope, accelerometer, mechanical rotating device, and signal solving circuit. By utilizing high-precision fiber optic gyroscopes to sense the Earth's rotational angular velocity and accelerometers to sense the gravity acceleration component with tilt compensation, the true north azimuth of the carrier can be quickly and autonomously determined.
The north finder has the characteristics of compact structure, light weight, high measurement accuracy, strong environmental adaptability, high reliability, fast directional speed, and high degree of automation.
2. Performance parameters
Parameter | Index | |
Power supply | Working voltage | 24V (default) or 12V optional |
Consumption | <5W (instantaneous power consumption<10W) | |
Performance index | Way of working | Static state | |
Digital output mode | RS422, RS232, RS485 interfaces are optional | ||
North search time | <3min | ||
Pitch and roll | Measuring range | ±30° | |
Measurement accuracy | ±0.05º(RMS) | ||
Azimuth | Measuring range | 0~360º | |
Measurement accuracy | 0.3 °, 0.5 º optional (RMS) | ||
| operation temperature | -40~+65℃ | |
storage temperature | -45~+70℃ | ||
vibrate | 5~5.5Hz，25.4mm 5.5Hz~200Hz | ||
1.5g (RMS)； Direction: Installation direction | |||
Time: 12 minutes; Cycle times: 3 times. | |||
impact | 10g, 11ms, half sine wave, direction: installation direction, frequency: 3 times | ||
Physical property | External dimensions | Φ78mm * 117mm | |
Weight | <1Kg | ||
3. Communication Protocol
Data rate: 115200bit/s. 1 start bit, 8 data bits, no checksum, 1 stop bit, a total of 10 data bits.
3.1 Input Data Format:
Explanation: The input data includes: frame header, latitude, confirmation instruction, a total of 10 bytes, specifically:
Byte count |
0 |
1 |
2~5 |
6 |
7 |
8 |
9 |
Significance |
0x7e |
0x7e | Input latitude (floating point 4 bytes, High position in front, low position in back) |
0x31 |
0x33 |
0x31 |
0x34 |
3.2 Output Data Format
The output data consists of 43 bytes, with the following meanings:
Byte count | 0 | 1 | 2~5 | 6~9 | |||
Significance |
0x7e |
0x7e | System time (floating point 4 bytes, high) Position at the front, lower position at the back) | Yaw angle (floating point 4 bytes, high bit in) Front, low at the back) | |||
Byte count | 10~13 | 14~17 | 18~21 | ||||
Significance | Pitch angle (floating point 4 bytes, high) Position at the front, lower position at the back) | Roll angle (floating point 4-byte, high bit) At the front, low at the back) | Accelerometer data (floating point 4-byte, High position in front, low position in back) | ||||
Byte count | 22~25 | 26~29 | 30~33 | ||||
Significance | Gyroscope data (floating point 4 bytes, High position in front, low position in back) | Gyroscope temperature (floating point 4 bytes, high) Position at the front, lower position at the back) | GPS longitude (floating point 4 bytes, high bit) At the front, low at the back) | ||||
34~37 | 38 | 39 | 40 | 41 | 42 | ||
GPS latitude (floating point 4 bytes, high-order before low order) | GPS is valid (A) Effective positioning, V invalid positioning) | System Status (S) Waiting to search north, R is currently searching north, D |
Transposition position |
0xeb |
0xeb | ||
|
|
| North search completed） |
|
|
|
3.3 Lead definition: Y11-1412 aviation plug connector
Line number | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
Significance | +24
V |
NC | 422
R- | 422
R+ | 422
T- | 422
T+ |
NC | +24
V |
NC |
GND |
NC |
GND |
4. Installation dimensions
Figure 1 Installation dimension diagram of north finder: Installation hole 3 * Ø 3.3mm, height 117mm
5. General Quality Characteristics Requirements
a) Use the platform to fix and install equipment.
b) The specific environmental adaptability is as follows:
a) Working temperature: -40 ℃ to+45 ℃
High temperature operation: According to GJB 150.3A-2009; Program II” Execution, working temperature is+55 ℃; Low temperature operation: According to GJB 150.4A-2009; Program II” Execution, working temperature is -40 ℃;
b) Storage temperature: -45 ℃~+70 ℃
High temperature storage: According to GJB 150.3A-2009; Program I” Execution, storage temperature is+60 ℃; Low temperature storage: According to GJB 150.4A-2009; Program I” Execution, storage temperature is -45 ℃;
c) Low pressure: In accordance with GJB150.2A-2009 "Environmental Test Methods for Military Equipment Laboratories Part 2: Low pressure (Altitude) Test", the pressure is 57kpa and will be evaluated along with the system;
d) Rain exposure: in accordance with the procedure of GJB150.8A-2009 "Environmental Test Methods for Military Equipment Laboratories Part 8: Rain exposure Test"
1. According to the system assessment;
e) Damp heat: in accordance with the provisions of GJB150.9A-2009 "Environmental Test Methods for Military Equipment Laboratories Part 9: Damp heat Test", and evaluated with the system;
f) Mold: Complies with the provisions of GJB150.10A-2009 "Environmental Test Methods for Military Equipment Laboratories Part 10: Mold Test" and is assessed with the system;
g) Salt spray: in accordance with GJB150.11A-2009 "Environmental Test Methods for Military Equipment Laboratories Part 11: Salt Spray Test"
Regulations, assessed with the system;
h) Vibration: Complies with the provisions of ground equipment in GJB150.16A-2009 "Environmental Test Methods for Military Equipment Laboratories - Vibration Test";
i) Impact: According to GJB 150.18A-2009; Program I” The relevant requirements are that the shock pulse wave is a half sine wave, the peak acceleration is 30g, the pulse duration is 25ms, and each axis (choose one axis of symmetry) is continuous for 3 times;
j) Sand and dust: comply with procedures I and II of GJB150.12-2009 "Environmental Test Methods for Military Equipment Laboratories - Sand and Dust Test"
regulations.
c) Electromagnetic compatibility
The electromagnetic compatibility of the system should meet the requirements of test items CE102, CS101, CS106, CS112, CS114, CS115, CS116, RE102, and RS103 in GJB151B-2013 "Requirements and Measurement of Electromagnetic Emission and Sensitivity of Military Equipment and Subsystems"
Meet the system usage requirements.
d) Reliability requirements
Mean time between failures (MTBF): ≥ 10000h.
e) Maintainability
Mean Time to Repair (MTTR): ≤ 0.4 hours.
f) Security
a) The selected parts, materials, and production processes should not pose potential hazards;
b) Parts that may come close during operation, adjustment, and maintenance should not carry high pressure, burrs, toxic gases, chemical combustion, or other hazards.
g) Interchangeability
When designing, interchangeability should be considered, and the same unit should be interchangeable. Continuous working hours
Continuous working time: ≥ 24 hours.
