The Wiimote has been used for many cool projects over the past few years. It is a very powerful device - especially for the price. Over the summer I was doing some fitness testing with my soccer team and we were using stopwatches to time sprints, agility tests etc. With any human measurement there is inherent error, and even more so when taking measurements of (hopefully) fast moving objects (people). So I thought I would learn a bit about interacting with the Wiimote and make an automated stopwatch. To do this I used the Wiimote's infrared camera to detect an IR LED that was placed across from it. Whenever someone passes between the Wiimote and the IR-LED the signal goes away and the computer knows to start the timer. Using a second Wiimote further down the line we can stop the timer at the right moment and get a very accurate time.
To interface with the Wiimote I used OSCulator. Its a great app (Mac only) that allows you to interface the Wiimote and many other Open Sound Control devices to your computer. I then sent the Wiimote's IR signal data to an Open Frameworks app that would start and stop the clock at the appropriate times.
Click here to download the source code and try it for yourself. (NOTE: this code is setup for 1 Wiimote)
For hardware, all you need is a Wiimote, and an IR LED or any remote control that you can keep in the on position to act as your IR source. For the software you will need openFrameworks (latest version 0072). If you are running Visual Studio or Code Blocks just copy over the "src" folder and the "bin/data" folder and make sure to include the addons: ofxOsc, ofxUI (download here), ofxXmlSettings. Also you will need to find another way to interface with the Wiimote since OSCulator is Mac only for now.