VR-Virtual Reality

One of the first commercially available headsets was the Forte VFX1 which was announced at CES in 1994. The VFX-1 had stereoscopic displays, 3-axis head-tracking, and stereo headphones. Another pioneer in this field was Sony who released the Glasstron in 1997, which had an optional positional sensor which permitted the user to view the surroundings, with the perspective moving as the head moved, providing a deep sense of immersion. One novel application of this technology was in the game MechWarrior 2, which permitted users of the Sony Glasstron or Virtual I/O's iGlasses to adopt a new visual perspective from inside the cockpit of the craft, using their own eyes as visual and seeing the battlefield through their craft's own cockpit.

The Virtual Reality (VR), which consists in simulating physical presence in computer-generated environments, whether they are inspired of real places (past or existing) or completely imaginary ones. It was created because of the resurgence of Virtual Reality in recent times, mainly thanks to the Oculus Rift project which goal is to provide an affordable wide FOV head-mounted display (HMD) to the masses. It consists of a stereoscopic head-mounted display (providing separate images for each eye) and head motion tracking sensors (which may include gyroscopes, accelerometers, structured light systems, etc.). Some devices also include headphones, eye tracking sensors and gaming controllers

Basically, VR is a theory based on the human desire to escape the real world boundaries and this is done by embracing the cyber world. It is a new form of human machine interaction that is beyond keyboard, mouse or even touch screen for that matter. It is a means by which one can

interact with full visual immersion. Immersion is based on two main components: depth of information and breadth of information. Depth of information includes resolution, quality and effectiveness of audio visuals etc. Breadth of information is the number of sensory present at a time. VR is implemented by using interactive devices like gloves headsets or helmets.

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Masked Shaped Goggle device that works along with computers or mobiles. Other VR headsets have problem of motion sickness to the user post its usage. But here is a new technology which claims to have solved this problem of motion sickness and dizziness post the usage. This new

technology is oculus rift.

The Oculus Rift is a light weight headset that allows a user to step into the game and look in any direction. The Oculus Rift is currently present in developer kits versions. Two developer kit versions have been released namely Developer Kit version 1 (DK1) and developer kit version 2 (DK2).

  

INSIDE VIEW

The inside view of the oculus rift goggles is as shown in the figure

 

The oculus rift kits come with three sets of lenses A, B and C. lens pair A is to be used by people who have excellent long sighted eyesight as the rift is focused at infinity. The pairs B and C are to be used by people having problems with near sightedness, though cannot be used by all, especially people with major vision complications.

Also precise care should be taken while changing the lenses. A tiny dust particle if gets settled on the lens creates a dead pixel view in the VR. To worsen it further one can expect dust particles in both the lenses at different locations.Furthermore glasses can also be worn along with the oculusrift goggles, provided that the glasses are not huge.

WORKING

How does VR work? How does wearable tech make you think you're standing on Mars when you're actually about to bump into the kitchen counter?

The headset set-up is being used by Oculus, Sony, HTC, Samsung and Google and usually requires three things. A PC, console or smartphone to run the app or game, a headset which secures a display in front of your eyes (which could be the phone's display) and some kind of input - head tracking, controllers, hand tracking, voice, on-device buttons or trackpads.

Total immersion is what everyone making a VR headset, game or app is aiming towards - making the virtual reality experience so real that we forget the computer, headgear and accessories and act exactly as we would in the real world. So how do we get there?

VR headsets like Oculus Rift and PlayStation VR are often referred to as HMDs and all that means is that they are head mounted displays. Even with no audio or hand tracking, holding up Google Cardboard to place your smartphone's display in front of your face can be enough to get you half-immersed in a virtual world.

The goal of the hardware is to create what appears to be a life size, 3D virtual environment without the boundaries we usually associate with TV or computer screens. So whichever way you look, the screen mounted to your face follows you.

VR headsets use either two feeds sent to one display or two LCD displays, one per eye. There are also lenses which are placed between your eyes and the pixels which is why the devices are often called goggles. In some instances, these can be adjusted to match the distance between your eyes which varies from person to person. 

 

These lenses focus and reshape the picture for each eye and create a stereoscopic 3D image by angling the two 2D images to mimic how each of our two eyes views the world ever-so-slightly differently. Try closing one eye then the other to see individual objects dance about from side to side and you get the idea behind this. 

 

One important way VR headsets can increase immersion is to increase the field of view i.e. how wide the picture is. A 360 degree display would be too expensive and unnecessary. Most high-end headsets make do with 100 or 110 degree field of view which is wide enough to do the trick.And for the resulting picture to be at all convincing, a minimum frame rate of around 60 frames per second is needed to avoid stuttering or users feeling sick. The current crop of VR headsets go way beyond this - Oculus is capable of 90fps.

 

Head tracking

 

Head tracking means that when you wear a VR headset, the picture in front of you shifts as you look up, down and side to side or angle your head. A system called 6DoF (six degrees of freedom) plots your head in terms of your x, y and z axis to measure head movements forward and backwards, side to side and shoulder to shoulder, otherwise known as pitch, yaw and roll.

There's a few different internal components which can be used in a head-tracking system such as a gyroscope, accelerometer and a magnetometer. Sony's PSVR also uses nine LEDs dotted around the headset to provide 360 degree head tracking thanks to an external PS4 camera monitoring these signals, Oculus has 20 lights but they are not as bright.

Head-tracking tech needs low latency to be effective - we're talking 50ms or less or we will detect the lag between when we turn our head and when the VR environment changes. The Oculus Rift has an impressively minimised lag of just 30 milliseconds. Lag can also be a problem for any motion tracking inputs such as PS Move-style controllers that measure our hand and arm movements.

Finally, headphones can be used to increase the sense of immersion. Binaural or 3D audio can be used by app and game developers to tap into VR headsets' head-tracking technology to take advantage of this and give the wearer the sense that sound is coming from behind, to the side of them or in the distance.

Motion tracking

Head tracking is one big advantage the as-yet unreleased premium headsets have over the likes of Cardboard. But the big VR players are still working out motion tracking. When you look down with a VR headset on the first thing you want to do is see your hands in a virtual space.

For a while, we've seen the Leap Motion accessory - which uses an infrared sensor to track hand movements - strapped to the front of Oculus dev kits. We've also tried a few experiments with Kinect 2 cameras tracking our flailing bodies. But now we have exciting input options from Oculus, Valve and Sony.

Oculus Touch is a set of prototype wireless controllers, designed to make you feel like you're using your own hands in VR. You grab each controller and use buttons, thumbsticks and triggers during VR games. So for instance, to shoot a gun you squeeze on the hand trigger. There is also a matrix of sensors on each controller to detect gestures such as pointing and waving.

Eye tracking

 

Eye tracking is possibly the final piece of the VR puzzle. It's not available on the Rift, Vive

Well, an infrared sensor monitor's your eyes inside the headset so FOVE knows where your eyes are looking in virtual reality. The main advantage of this - apart from allowing in-game characters to more precisely react to where you're looking - is to make depth of field more realistic.

In standard VR headsets, everything is in pin-sharp focus which isn't how we're used to experiencing the world. If our eyes look at an object in the distance, for instance, the foreground blurs and vice versa. By tracking our eyes, FOVE's graphics engine can simulate this in a 3D space in VR. That's right, blur can be good.

Headsets still need hi-res displays to avoid the effect of looking through a grid. Also what our eyes focus on needs to look as life-like as possible. Without eye tracking, with everything in focus as you move your eyes - but not your head - around a scene, simulation sickness is more likely. Your brain knows that something doesn't match up.