Attitude and Heading Reference System
AHRS-E304
Description:
The signals from three solid state angular rate sensors are coordinate transformed and then integrated to produce attitude and heading outputs that reflect normal aircraft attitude coordinates. These attitude and heading signals are compared against a triaxial accelerometer and a triaxial fluxgate magnetometer to derive gyro drift error. These errors are filtered over a long time constant and are used to adjust biases in the system so that the long-term convergence of the system is to the vertical references and the magnetic heading reference. A velocity input is used to calculate compensations for centrifugal forces and velocity changes on the vertical reference to improve the overall stability and accuracy of the attitude and heading data.
This is a microprocessor-based system using a 16 bit A/D converter, a 12 bit D/A converter and an RS-232 interface. The microprocessor has stored parameters for all the sensor inputs to correct bias, scale factor, axis alignment, and others. The analog attitude and heading outputs are updated 71.11 times per second. The serial interface is highly configurable and provides access to almost all operational parameters.
Applications:
The AHRS-E304 is useful for land, sea and airborne applications. It can be used to drive an attitude indicator flight display, for control and stabilization of remote piloted subs or aerial vehicles, and for robotics research and road surface measurement.
Features:
| • Solid State, Strapdown System | |
| • Low Cost, Low Power | |
| • Rugged, High Reliability | |
| • Vibration Resistant | |
| • Analog and RS-232 Serial Outputs | |
| • PC Heading Calibration | |
| • Two Year Limited Warranty | |
| • Engineering Support |
Attitude and Heading Reference | |||
Attitude | |||
| Range: Bank | ±180° | ||
| Range: Elevation | ±90° | ||
| Resolution: | 0.02° | Binary mode (14 bit) | |
| Analog Scale Factor: | 18°/V | ±10V Output | |
| Accuracy: Static | ±0.25° | ||
| * | Accuracy: Dynamic | ±2% | |
Heading | |||
| Range: | 0° - 360° | ||
| Resolution: | 0.02° | Binary mode (14 bit) | |
| Analog Scale Factor: | 18°/V | ±10V Output | |
| † | Accuracy: Static | ±1° | |
| * | Accuracy: Dynamic | ±2% | |
Angular Rate | |||
| Range: Roll, Pitch, Yaw | ±100°/sec | ||
| Resolution: | 0.01°/sec | Binary mode (14 bit) | |
| Analog Scale Factor: | 10°/sec/V | ±10V Output | |
| Scale Factor Accuracy: | 1% | ||
| Bias: Roll, Pitch, Yaw | < ±0.02°/sec | ||
| Non-Linearity: | < 0.03% | Full scale range | |
| Bandwidth: | 20 Hz | ||
Acceleration | |||
| Range: X, Y, Z | ±10g | ||
| Resolution: | 4mg | ||
| Analog Scale Factor: | 1g/V | ±10V Output | |
| Scale Factor Accuracy: | 1% | ||
| Bias: X, Y, Z | < ±5mg | ||
| Non-Linearity: | < 1% | Full scale range | |
| Bandwidth: | 20 Hz | ||
Magnetic | |||
| Range: X, Y, Z | ±1000 mGauss | ||
| Resolution: | 0.1 mGauss | Binary mode (14 bit) | |
| Scale Factor Accuracy: | 1% | ||
| Bias: X, Y, Z | < ±5 mGauss | ||
| Non-Linearity: | < 0.01% | Full scale range | |
| Bandwidth: | 10 Hz | ||
Environmental | |||
| Temperature: Operating | -30°C to +60°C | ||
| Temperature: Storage | -55°C to +85°C | ||
| Vibration: Operating | 5g rms | 20 Hz to 2 kHz | |
| Vibration: Survival | 10g rms | 20 Hz to 2 kHz | |
| Shock: Survival | 500g | 10mS ½ sine wave | |
Electrical | |||
| Frame Rate: | 71.1Hz | Maximum | |
| Startup Time: Data | 5 sec | ||
| Startup Time: Fully operational | 10 sec | ||
| Input Power: | 10 to 30VDC | 4.8W | |
| Input Current: | 350mA @ 12VDC | 200mA @ 24VDC | |
| Input Velocity: (Optional) | ±10VDC | Full scale (±800kph) | |
| Digital Output: | RS-232 | ||
| Analog Output: | ±10VDC | ||
Physical | |||
| Axis Alignment: | < 0.1° | ||
| Size: Including Mounting Flanges | 3.24”W x 5.78”L x 4.68”H | 8.2 x 14.7 x 11.9 (cm) | |
| Weight: | 32oz (2lb) | 910 grams (0.9Kg) | |
| Connection: RS-232 / Analog Outputs | 25 pin male "D" subminiature | ||
| Connection: Power | 4 pin male MS-3110-P8-4P | ||
| * | Assumes accurate velocity data. Actual accuracy can be calculated as the listed percentage multiplied by the change in value over the entire dynamic maneuver. | ||
| † | Static heading accuracy is dependent on the magnetic environment. This sensor will meet or exceed this spec within the 48 contiguous United States. | ||
| Specifications are subject to change without notice. | |||
AHRS Block Diagram | |||
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AHRS-E304 Dimensions | |||
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