[pbalau]

I tried to do this, I wanted to track my cats. My problem was that I was trying to fix this by using one tech. I did a fair bit of research on Bluetooth, cheap 433mhz radio, accelerometers etc. All had drawbacks, from size, cost, availability, missing features (eg the signal strenght) and I gave up when I moved to London.

If I try this again, and by that I mean when I try this again, I will go a different route. The core will be a pair of accelerometers, with a nfc tag, sending to a central unit the acceleration data and wifi signal strenght. A network of nfc readers will send info about what tags are they seeing. Maybe even some cameras.

The acceleration data will provide fine movement data and the rest is supposed to allow for data calibration and coarse tracking. Not an easy project, but should be fun.