Virtual Reality Devices

1. Head-Mounted Display (HMD)-goggles: it is the 1st & the most important device to provide the user with an immersive experience in his virtual environment. The device is like a headset with two monitors one for each eye. It could be as a helmet or a pair of glasses. HMD contains two systems, the optical system & a tracking system. The first system job to channels images from the screen to the user’s eyes & view the virtual world. However, the tracking system will track the position & the movements of the users’ head & update the image or the representation to follow that movement. As a result, immersive experience will be developed when the user has the ability to look & walk in his virtual environment.

2.Boom (Binocular Omni-Orientation Monitor): Boom is a head-coupled stereoscopic display device & one of the oldest virtual Reality displays. This device has a multi-link arm connected to a box which contains screens and an optical system. User can adjust & guide that box to any position after looking through two holes to determine the position of objects in the virtual environment.

3. Cave (Cave Automatic Virtual Environment): The cave is a cube-shaped room supplied with projectors to display images on walls, ceiling and floor to provide the illusion of immersion. Through special stereo glasses representing 3D images, users can enter the cave to walk freely. As well, a head tracking system is used to adjust stereo projection to the current position of the leading viewer. Therefore, the CAVE was the first virtual reality system which allows several users to participate in the experience concurrently. On the other hand, CAVE displays are very expensive and require more space than other systems.

Because there is no visual contact between the user & the physical world, input & interacting devices are important for the user. These devices will allow the user to navigate & interact with virtual objects in the virtual environment & develop more real experiences.

• input devices are:

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   Data gloves: have sensors for position sensing & tracking. These sensors Read the angle of each of the finger joints in the hand to tracks movements. As well, it allows the user to point & manipulate objects on the computer.
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  Joysticks
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  hand-held wands
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  Force balls/tracking balls
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  Voice recognition
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  Motion trackers/bodysuits