IMU & AHRS
Low SWaP-C and ITAR-free inertial measurement units engineered for navigating extreme environments and delivering seamless integration.
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IMU & AHRS
Explore our MEMS and FOG-based IMU solutions built for commercial and defense applications.
A70
A90
Roll & Pitch
0.01 °
0.005 °
Heading
0.1 ° seclat
0.01 ° seclat
Bias Instability
0.01 °/hr
0.001 °/hr
Output Rate
1000 Hz
1000 Hz
Technical Validation
Rigorous 8-Hour Calibration
Our IMU products undergo an intensive temperature calibration from -40°C to 85°C to ensure accuracy in extreme field operations. A high output rate of 1000 Hz ensures high dynamic performance in the most demanding applications.
Unified Communication Protocol
Our IMU products use a common communication protocol, enabling customers to extend their product range by moving up or down the accuracy spectrum without incurring re-engineering costs.
Vertically Integrated Manufacturing
From precision component creation to final system assembly, this approach allows Advanced Navigation to bypass broader market supply chain stagnation and deliver navigation units rapidly, often within weeks.
FAQs
What is an Attitude and Heading Reference System (AHRS)?
AHRS stands for Attitude and Heading Reference System. Attitude refers to an object’s orientation relative to the horizontal plane that is parallel to the horizon. This is often described as pitch and roll.
Heading is the direction a vessel is pointing towards relative to True North.
An AHRS is often used in aircraft and can also be used as a navigation aid for ground-based robots. Other uses for AHRS include measuring human movement by sports scientists.
How does an AHRS work?
An AHRS consists of IMUs (inertial measurement unit) on three orthogonal axes (commonly referred to as X, Y and Z). Typically these IMUs contain:
- Accelerometers
- Gyroscopes
- Magnetometers
Accelerometers measure the linear force acting on the vehicle. This includes gravity, which is used to determine the orientation of the vehicle with respect to the centre of the Earth.
Gyroscopes measure the rotational force acting on the vehicle.
Magnetometers measure magnetic fields. If the position of the vehicle is known, the vehicle heading relative to magnetic north can be determined. Heading relative to True North can also be found due to the known declination value.
Additional sensors can be incorporated to assist an AHRS. A common addition is the use of a dual antenna GNSS receiver (global navigation satellite system). By using two GNSS antennas the vehicle heading can be determined to a much higher accuracy.
If minimal SWaP-C is not required, higher accuracy gyroscopes based on fiber optic technologies (FOG) can dramatically increase attitude and heading accuracy.
Why use heading reference systems?
AHRS are often made from micro-electromechanical systems, or MEMS. Therefore the compact and lightweight nature of an AHRS allows it to be used in vessels that require a small SWaP-C (size, weight, power and cost).
This small SWaP-C makes AHRS ideal for unmanned aerial vehicles (UAV) which need accurate measurements but can’t carry an instrument that is heavy or bulky.
Typically an AHRS is used for:
- Surveying
- Autonomous manufacturing robots
- Underwater navigation
- Surface marine navigation
- Tracking human movement for sports science
What are the differences between an Inertial Navigation System (INS), Attitude & Heading Reference System (AHRS) and Inertial Measurement Unit (IMU)?
The output of an IMU is raw sensor data from the accelerometer (linear acceleration), gyroscope (rotational rates) and optionally a magnetometer (magnetic heading).
This information can be used for measuring the motion of an object in 3 dimensions (for example, am I pointing up and how fast am I spinning). An attitude heading and reference system (AHRS) contains an IMU, however, it also has onboard processing that applies filtering/sensor fusion to the IMU data to accurately determine the orientation (represented as roll, pitch and heading/yaw), velocity and relative position.
An AHRS coupled with a global navigation satellite system (GNSS) that provides absolute position and velocity information is referred to as an Inertial Navigation System (INS). An INS fuses AHRS and GNSS information to provide a very reliable representation of a system’s absolute position, orientation and velocity.