Engineers Patrick Slade, Mykel J. Kochenderfer, Scott L. Delp and Steven H. Collins of Stanford University published a paper this week detailing their Raspberry Pi-based fitness tracking project. Using a Raspberry Pi 3 B+, the team developed a more accurate method for tracking how many calories your workout is actually burning in real-time.
According to the team, their Pi-based system is able to provide a more accurate output than commercial smartwatches at a much lower cost. The best Raspberry Pi projects are ones you can make yourself, and the engineers made this project open source for any makers interested in recreating their work.
The hardware used is quite basic when it comes to Raspberry Pi projects, totaling about $100.
The engineers chose a 3 B+ with the help of an Adafruit Perma-Proto HAT to power the operation. A battery is necessary to make the unit mobile. These components are mounted to the user on a belt around the hips.
Additionally, two sensors are attached to one leg and provide the real-time input needed for the Pi. The leg sensors are inertial measurement units and attach to a TCA9548A multiplexer installed on the Perma-Proto HAT. The user wears one around the thigh and the other around their calf. Together, they measure the acceleration and rotation of the leg as it’s moving.
The data is compiled to determine things like whether or not the user is resting and how much energy they’re expending.
Want to get a closer look at your own workout performance? Visit the full project breakdown at Nature.com to read more about how the system works and maybe recreate it yourself.