IMU

FOUR INERTIAL MEASUREMENT UNIT COMPONENTS

1. Accelerometer

   This is a sensor that measures the specific force (the body mass normalizes the force). It provides the acceleration across the x, y and z axes in its local frame.

2. Gyroscope

   This is a sensor that measures angular velocity around the x, y and z axes, in its local frame. Generally, it integrates the measurement results in the angles themselves.

3. Magnetometer

   This is a sensor that measures the Earth’s magnetic field and provides the heading (the compass is one such device). If it is included in the IMU, we commonly describe it as a “nine-axis IMU.”

4. Barometer

   This is a sensor that measures air pressure and can provide altitude.

https://builtin.com/internet-things/inertial-measurement-unit