IMU Calibration

The Reflex has three built in Inertial Measurement Units (IMU) used for measuring the triaxial accelarations as well as angular velocities. The model used on the Reflex is the InvenSense ICM-42688P which consists of both an accelerometer and a gyroscope. The calibration of these sensors is easiest done prior to mounting the Reflex on the drone and so, must be done first.

Accelerometer calibration

The accelerometers must be calibrated prior to mounting. Calibration can be started on the web interface by navigating to:

Web Interface: Calibration > Accelerometer

After clicking the Start Calibration button, put the Reflex on a flat surface and wait for the displayed bin to fill to 100%. Repeat for each side of the Reflex. After all bins are filled, calibration is completed.

Gyroscope calibration

The gyroscope calibrates at startup. For it to successfully calibrate, the drone needs to be standing still (see the Standing Still flag on the Dashboard).

Status of the gyroscope calibration can be monitored in the Gyro entry of the Sensor Status part of the Dashboard. When the entry shows an "Ok", then the gyroscope can be considered to be calibrated.