Calculation of the activity

The "Activity" is calculated directly from the accelerometer: 3-axis sensors sampled at 64 Hz (13-bit resolution. LSb: 3.9 mg. where 1g = 9.8 m/s2).

 

Every second, we compute the average acceleration vector length over the 64 samples: SQRT(accX^2 + accY^2 + accZ^2) 

 

For more details, please see below:

Activity: Signal based on the accelerometer intensity vector.

• Source data: acceleration
• Method of calculation:
  • Highpass at 2.65 Hz on the 3-axis independently
  • Vector of acceleration. (accX^2 + accY^2+accZ^2)^.5
  • Averaged over the last second
• Frequency: 1 Hz
• Resolution 3.9 mG.
• Dynamic range +- 16G
• Unit G
• Unit (binary download): G/256

Additionally, refer to this documentation for any other metric calculations: https://api.hexoskin.com/docs/index.html#introduction   

 

Keywords: data export, data analysis, activity tracking, API