5 Things to look for when evaluating an IMU
Roll, Pitch and Heading accuracy
Determines how accurate the measured values are compared to their true values. Impacts the positional accuracy of the pointcloud, positional error increases with range.
The lower the Gyro-bias the less effort is required for initialising the system
Gyro Random Walk
The noise of the sensor, which causes INS error to grow over time during GNSS outages. The lower the Gyro-RW the better the system will perform without GNSS
The higher the measurement rate the less interpolation is required during laser scanner geo-encoding resulting in improved accuracy.
Can you easily move the IMU around the world or will you need an export license to do so?
Measures of Performance and Error
The performance of the INS (Inertial Navigation System) is also often quoted and takes into account the accuracy of the IMU and a GNSS (Global Navigation Satellite System) when combined by a Kalman Filter.
An INS filter, referred to as a Kalman Filter , combines the different measurements taking into account estimated errors to produce a trajectory including time, position, and attitude.