Which specification to look for the right IMU/AHRS/INS selection

In fact, frequently, the lack of information on the reliability of the IMUs leads to its incorrect application.

The reliability of the IMUs specifications is very important for their correct commercial or navigational usage.  If we use commercial grade IMU for navigational use we are prone to get bad data.

One of the most important factor in determining the quantity of noise in sensor data.

The three important specifications to consider when choosing IMUs are:

  • bias instability,

  • scale factor stability, and

  • random walk (noise) 

​These specs are selected because they are usually are the cause of the largest errors present in sensor outputs.   Below we are giving a comparision of these specification for the XSENs MTi 10, MTi 100 and MTi-G-710 series IMUs.

Specification XSENs MTi10 XSENs MTi100 XSENs-G-710
  Gyroscopes
Bias Stability (deg/h)
18º/h 10º/h
Rate of turn: 20o/h
Acceleration: 0.02 m/s2
Magnetic field: 0.1 mGauss
Static pressure: 100 Pa/yr
Scale Factor (ppm)
10 ppm or external reference 10 (1w. GPS) or ext. ref. 
1 ppm (GPS available)
Angular Random Walk (Noise) (deg/√h / √Hz)
0.03º/s/√Hz 0.01º/s/√Hz - 0.015º/s/√Hz
Rate of turn: 0.05 deg/s/√Hz
Acceleration: 0.002 m/s2/√Hz
Magnetic field: 1.5 mGauss
Static pressure: 4 Pa/√Hz (0.3 m/√Hz)
  Accelerometers
Bias Stability (μg/h) 
40 μg 40 μg  
Scale Factor (ppm)
  -  
Velocity Random Walk (Noise)
(mg/h/√ )
80 μg/√Hz - 150 μg/√Hz 80 μg/√Hz - 150 μg/√Hz