More general points
I cut some explanation from the video to keep the length down, and would have liked to include the following points:
- I haven't managed to figure out how to read the heart rate data results from the wristband I'm using (see explanation above). As a result, the heart rate shown in the video is a constant value of 80. I'm still working on this!
- I'm using the excellent TinyGPS++ library by Mikal Hart to parse the NMEA data from the GPS module. This library "just works" and makes it incredibly easy to get position data from the module as well as distance from a fixed point. Thanks, Mikal!
- In the video I have displayed a fixed GPS location on screen and in the text message, to avoid publicly showing my real GPS location. This is not a bug, the GPS functions work perfectly well!
- I meant to show a screenshot of the phone to show clearly the full content of the emergency text message. Hopefully you can read it on the video, but if not it reads like this: "WARNING - PANIC pressed: HR 80bpm, 405645m from home, location 48.85825N, 2.294517E." The large distance from home is my real distance from the "home" location set in the software, whereas the reported location is the fixed point mentioned above (very close to the defined "home" point, but not my real location in this case).