QUOTE(pablot @ Nov 7 2006, 09:07 AM)

well hello mr senor bar. I had totally missed that, I thought it was all gyros and accellerometers inside the remote. very interesting.
/pablot
well it actually is all accelerometers for the motion sensing in the Wii-Remote and nunchuck attachment.
The sensor bar is for the POSITIONAL sensing... basically the Wii-remote in addition to motion sensing also can point at the screen like a light gun (Time Crisis, Area 51, Virtua Cop, etc.).
AFAIK that's the only function of the sensor bar, motion controlled is still handled entirely bu accelerometers internally.
IR sensors were used instead of traditional light gun tech because traditional light gun tech only works properly on CRT displays, but IR sensors can work on ANY display.
It's not new either, there is a light gun called the "Top Gun" that uses IR sensor bars that works with the PS2, Xbox and PCs.
If the motion control works like the other motion control systems I've used it will have 2 three-axis accelerometers. Imagine the controller is a flat piece of cardboard. one accelerometer is in the top left and the other is in the bottom right.
When both register +X it meas the controller is moving straight along the X axis, if one registers +Z and the other -Z it means that it's rotating around the X axis. They're offset in opposite corners so that it can detect rotation about any of the 3 linear axis. Not saying that's how it works but that's how other systems I've used work.