Virtual Reality - What it is and How it Works Imagine being able to point into the sky and fly. Or perhaps walk through space and connect molecules together. These are some of the dreams that have come with the invention of virtual reality.
With the introduction of computers, numerous applications have been enhanced or created. The newest technology that is being tapped is that of artificial reality, or "virtual reality" (VR). When Morton Heilig first got a patent for his "Sensorama Simulator" in 1962, he had no idea that 30 years later people would still be trying to simulate reality and that they would be doing it so effectively. Jaron Lanier first coined the phrase "virtual reality" around 1989, and it has stuck ever since. Unfortunately, this catchy name has caused people to dream up incredible uses for this technology including using it as a sort of drug. This became evident when, among other people, Timothy Leary became interested in VR.
This has also worried some of the researchers who are trying to create very real applications for medical, space, physical, chemical, and entertainment uses among other things. In order to create this alternate reality, however, you need to find ways to create the illusion of reality with a piece of machinery known as the computer. This is done with several computer-user interfaces used to simulate the senses. Among these, are stereoscopic glasses to make the simulated world look real, a 3D auditory display to give depth to sound, sensor lined gloves to simulate tactile feedback, and head-trackers to follow the orientation of the head.
Since the technology is fairly young, these interfaces have not been perfected, making for a somewhat cartoonish simulated reality. Stereoscopic vision is probably the most important feature of VR because in real life, people rely mainly on vision to get places and do things. The eyes are approximately 6.5 centimeters apart, and allow you to have a full-colour, three-dimensional view of the world. Stereoscopy, in itself, is not a very new idea, but the new twist is trying to generate completely new images in real- time.
In 1933, Sir Charles Wheatstone invented the first stereoscope with the same basic principle being used in today's head-mounted displays. Presenting different views to each eye gives the illusion of three dimensions. The glasses that are used today work by using what is called an "electronic shutter". The lenses of the glasses interleave inflating air bladders in a glove, arrays of tiny pins moved by shape memory wires, and even fingertip piezoelectric vibrotactile actuators. The latter method uses tiny crystals that vibrate when an electric current stimulates them.
This design has not really taken off however, but the other two methods are being more actively researched. According to a report called "Tactile Sensing in Humans and Robots," distortions inside the skins cause mechanosensitive nerve terminals to respond with electrical impulses. Each impulse is approximately 50 to 100mV in magnitude and 1 ms in duration. However, the frequency of the impulses (up to a maximum of 500/s) depends oration simulations.
Such things as virtual wind tunnels have been in development for a couple years and could save money and energy for aerospace companies. Medical researchers have been using VR techniques to synthesize diagnostic images of a patient's body to do "predictive" modeling of radiation treatment using images created by ultrasound, magnetic resonance imaging, and X-ray. A radiation therapist in a virtual would could view and expose a tumour at any angle and then model specific doses and configurations of radiation beams to aim at the tumour more effectively. Since radiation destroys human tissue easily, there is no allowance for error.
Also, doctors could use "virtual cadavers" to practice rare operations which are tough to perform. This is an excellent use because one could perform the operation over and over without the worry of hurting any human life. However, this sort of practice may have it's limitations because of the fact that it is only a virtual world. As well, at this time, the computer-user interfaces are not well enough developed and it is estimated that it will take 5 to 10 years to develop this technology.
In Japan, a company called Matsushita Electric World Ltd. is using VR to sell their products. They employ a VPL Research head-mounted display linked to a high-powered computer to help prospective customers design their own kitchens. Being able to see what your kitchen will look like before you actually refurnish could help you save from costly mistakes in the future.
The entertainment industry stands to gain a lot from VR. u
