Methods of virtual reality
There are a number of methods by which virtual reality (VR) can be realized.
The first method is simulation-based virtual reality. Driving simulators, for example, give the driver on board the impression that he/she is actually driving an actual vehicle by predicting vehicular motion caused by driver input and feeding back corresponding visual, motion, audio and proprioceptive cues to the driver. The simulator normally consists of several systems as follows: a real-time vehicle simulation system performing real-time simulation of vehicle dynamics; motion, visual and audio systems reproducing vehicle motion, driving environment scenes and noise sensed by a driver during driving; a control force roading system acting as an interface between the driver and the simulator; an operator console for monitoring system operation; and system integration managing information and data transfer among subsystems and synchronization. The driving simulators have been used effectively for vehicle system development, safety improvement and human factor study.
Avatar image-based VR
With avatar image-based virtual reality, people can join the virtual environment in the form of real video as well as an avatar. The proposed image VR system can handle two types of users. One can participate in the 3D distributed virtual environment as form of either a conventional avatar or a real video. Background of the video is effectively eliminated to enhance the sense of reality. A user can select his/her own type of participation based on the system capability. Users with capture board and camera may select a video avatar while others select a conventional computer graphics-based avatar. Avatar image-based VR now provides pretty good interaction environment between human and computer far beyond the conventional desktop computer systems. High-speed networks become available with the advance of network technologies.
In projector-based virtual reality, modeling of the real environment plays a vital role in various virtual reality applications, such as robot navigation, construction modeling and airplane simulation. Image based virtual reality system is gaining popularity in computer graphics as well as computer vision communities. The reason is that is it provides more realism by using photo realistic images and the modeling procedure is rather simple. In generating realistic models, it is essential to accurately register acquired 3D data. Usually, camera is used for modeling small objects at a short distance.
Desktop-based virtual reality involves displaying a 3-dimensional virtual world on a regular desktop display without use of any specialized movement-tracking equipment. Many modern computer games can be used as an example, using various triggers, responsive characters, and other such interactive devices to make the user feel as though they are in a virtual world. A common criticism of this form of immersion is that there is no sense of peripheral vision, limiting the user's ability to know what is happening around them.
True Immersive Virtual Reality
Hypothetical virtual reality as immersive as consensus reality. Most likely to be produced using a Brain-computer interface. An intermediate stage may be produced by "Virtual Space" using a head-mounted display with head tracking and computer control of the image presented to the helmet.