This is a fantastic application of the Nintendo Wiimote. Timo Fleisch of Germany has created a system that uses some Wii remotes which can be purchased at any local department store and some IR LEDs which are also readily available to create a very usable virtual environment
The core of this VR setup is using the Nintendo Wiimote Controller as a tracking camera. As one might already know the Wiimote is equipped with an infra-red camera that is able to recognize up to four infra-red lights. The main idea now is to build a device with four infra-red LEDs that can be recognized by the Wiimote. This device call IR-LED beacon. Using the values of the 4 LEDs as recognized by the Wiimote use an algorithm to reconstruct the original position and orientation of the IR-LED beacon. Getting all 3 axis translations and all 3 axis rotation angles of the device is called 6 degree of freedom tracking – or short 6DOF tracking
You hold an item infront of a monitor which will be displaying the virtual item, above this screen there is a Wiimote mounted that is looking down towards the table. The item you hold has some IR LEDs mounted on it to allow the Wiimote camera to determine its exact orientation. A second Wiimote enhances the effect by looking at the user who is wearing a device with some more IR LEDs, now the system also knows where the users head is located. The computer generates and image on the screen based on the orientation of the hand held device in addition to the position of the users head
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