I've pretty much turned over this method (attaching hardware to the body) in favor of regular Wiimote altercations. I think infrared lights could be the key to better detection after all. If IR LEDs are on the body (knees and hands, I guess) and the Wiimote is aimed the waist, there's a good chance it could track everything. I read that the Wiimote's camera can track four points at a time... But can it track them accurately and distinguish them, or does it truncate their positions to two points? And what's the lens angle of this thing?
Of course, I'll run into testing this soon enough, but if you already know how the camera sends point data (especially if four coordinate pairs are passed), you can give me a very quick answer!
If the Wiimote isn't naturally up to the task, I'll have to (read: get to) use my own hardware for detection, like
these guys. And as the whole community seems to, I encourage you to
try it yourself! Most of my "free" time gets tied up otherwise, so as much as I want to see this turn out, I might not be able to build a dozen experiments.