Microsoft explains here the operation of its project Natal, derived mainly from the use of two cameras and the principles of the stereoscopic vision to recreate with a high detail 3D geometry the real environment perceived by both cameras:

Compatible with any Xbox 360 system, the “Project Natal” sensor is the world’s first to combine an RGB camera, depth sensor, multi-array microphone and custom processor

running proprietary software all in one device. Unlike 2-D cameras and controllers, “Project Natal” tracks your full body movement in 3-D, while responding to commands, directions and even a shift of emotion in your voice.

In addition, unlike other devices, the “Project Natal” sensor is not light-dependent. It can recognize you just by looking at your face, and it doesn’t just react to key words but understands what you’re saying. Call a play in a football game, and players will actually respond.

At the same time another  interface to recognize the movements of the player has been presented in E3, which also tries to go beyond the Nintendo Wiimote:

via: The Cosmonauts

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