The Input
(This is Part Two in an ongoing series which starts at Part One).
To answer all the questions raised in part one, there is only one thing we really need to know:
How far does our hamster run in a particular period of time?
The “how far” part should be quite easy, because the little critter is running in a fixed wheel – no need for a micro-GPS tracking bug here. Some mechanism for counting how many times the wheel turns should be sufficient.
So, how can we measure the rotations of a wheel like this? Well there are several ways, but the one I’ve gone for to start with, due both to the simplicity and the fact that I have the parts on-hand, is the reed switch. Read more »

Arduino
HobbyTronics
Maplin
SK Pang