Data description

The RAPID saves the sensor data in a row-column format. Each row represents one index step, and each of the 5 columns corresponds to a different variable. The accelerometer data are logged to the file at 2048 Hz, and the pressure data are updated at 100 Hz. This means that there are duplicate pressure sensor data, because all data are saved at 2048 Hz.

The first column contains the index of each data time step from 1 to 2048, and resets to a value of 1 after each second. It can be used in post-processing to detect missing or faulty data, which would occur if the index does not go exactly from 1 to 2048 during recording to the SD card.

The following table provides an overview of the sensor data structure, and the physical units are given in brackets.

Col 1	Col 2	Col 3	Col 4	Col 5
Index [1 to 2048]	AX [m/s2]	AY [m/s2]	AZ [m/s2]	P [mbar]