Virtual reality

VIRTUAL REALITY 2015 - 2016
CHAPTER 1
INTRODUCTION
Virtual Reality (VR) is an environment that is simulated by a computer. A three-dimensional
artificial environment which can be created using computer hardware and software and
presented to the user in such a way that it appears and feels like a real environment is called
as Virtual Reality. A person who uses such an environment can enter into the computer
generated virtual environment with the help of special gloves, goggles, ear phones etc… All
these special devices make use of sensors which help in detection of the required signals.
Virtual reality can be text-based or graphical based representation.
Virtual reality appears to offer educational potentials in the following areas:
(1) Data gathering and visualization,
(2) Project planning and design,
(3) The design of interactive training systems,
(4) Virtual field trips, and
(5) The design of experiential learning environments.
Virtual reality also offers many possibilities as a tool for non-traditional learners, including
the physically disabled and those undergoing rehabilitation who must learn (or relearn)
communication and psychomotor skills. Virtual reality offers professional applications in
many disciplines --- robotics, medicine, scientific visualization, aviation, business,
architectural and interior design, city planning, product design, law enforcement,
entertainment, the visual arts, music, and dance and concomitantly, virtual reality offers
potentials as a training tool linked to these professional applications. For example, just as
virtual reality is used as a tool by surgeons, it can be used by medical students training to
become surgeons.
Dept. of E&C, NCET, Bangalore Page 1

Fig 1.1:- Virtual Reality
Originally designed as a visualization tool to help scientists, virtual reality has been taken up
by artists as well. VR offers great potential as a creative tool and a medium of expression in
the arts. Creative virtual reality applications have been developed for the audio and visual
arts. An exhibit of virtual reality art was held at the Soho Guggenheim Museum in 1993 and
artistic applications of VR are regularly shown at the Banff Center for the Arts in Canada.
This trend is expanding Virtual reality has been applied to the theater, including a venerable
puppet theater in France. And virtual reality has a role to play in filmmaking, including
project planning and special effects. This has important implications for education, as
demonstrated by Bricken and Byrne's (1993) research (described later in this chapter) as well
as other projects.
1.1 VIRTUAL REALITY
Simply put, VR is a computerized simulation of natural or imaginary reality. Often the user
of VR is fully or partially immersed in the environment. Full immersion refers to someone
using a machine to shield herself from the real world. Partial immersion happens when a
person can manipulate a VR environment but isn't tucked or locked away in a machine.

However, virtual reality doesn't necessarily have to be "full immersion" to be considered a
true VR simulation. Games like Second Life on the PC and control devices like the Nintendo
Wii remote are VR-based products. These items let users interact with a VR environment that
is a computer simulation. These VR environments can be anything from a typical game, such
as Super Mario Brothers, to a fully detailed city reconstitution or a fictional fantasy land. The
only limit to a VR environment is the imagination and the resources that the creator has
available.
1.2 VIRTUAL REALITY HISTORY
The concept of virtual reality has been around for decades, even though the public really only
became aware of it in the early 1990s. In the mid 1950s, a cinematographer named Morton
Heilig envisioned a theatre experience that would stimulate all his audiences’ senses, drawing
them in to the stories more effectively. He built a single user console in 1960 called the
Sensorama that included a stereoscopic display, fans, odor emitters, stereo speakers and a
moving chair. He also invented a head mounted television display designed to let a user
watch television in 3-D. Users were passive audiences for the films, but many of Heilig’s
concepts would find their way into the VR field.
Philco Corporation engineers developed the first HMD in 1961, called the Head sight. The
helmet included a video screen and tracking system, which the engineers linked to a closed
circuit camera system. They intended the HMD for use in dangerous situations -- a user could
observe a real environment remotely, adjusting the camera angle by turning his head. Bell
Laboratories used a similar HMD for helicopter pilots. They linked HMDs to infrared
cameras attached to the bottom of helicopters, which allowed pilots to have a clear field of
view while flying in the dark

CHAPTER 2
VIRTUAL ENVIRONMENT
The origin of the term "virtual reality" is uncertain though it has been credited to The
Judas Mandala, a 1982 novel by Damien Broderick where the context of use is somewhat
different from that defined above. A related term coined by Myron Krueger, "artificial
reality", has been in use since the 1970s. "Cyberspace" dates to the 1982 short story "Burning
Chrome" and 1984 novel Neuromancer by the cyberpunk author William Gibson. The
concept of virtual reality was popularized in mass media by movies as The Lawnmower Man
(and others mentioned below), and the VR research boom of the 1990s was motivated in part
by the non-fiction book Virtual Reality by Howard Rheingold. The book served to demystify
the heretofore niche area, making it more accessible to less technical researchers and
enthusiasts, with an impact similar to what his book The Virtual Community had on virtual
community research lines closely related to VR.
2.1 FOUNDATION OF VIRTUAL REALITY
Virtual Reality (VR) refers to a technology which is capable of shifting a subject into a
different environment without physically moving him/her. To this end the inputs into the
subject's sensory organs are manipulated in such a way, that the perceived environment is
associated with the desired Virtual Environment (VE) and not with the physical one. The
manipulation process is controlled by a computer model that is based on the physical
description of the VE. Consequently, the technology is able to create almost arbitrarily
perceived environments.
Immersion is a key issue in VR systems as it is central to the paradigm where the user
becomes part of the simulated world, rather than the simulated world being a feature of the
user's own world.
The first “immersive VR systems” have been the flight simulators where the immersion is
achieved by a subtle mixture of real hardware and virtual imagery. The term "immersion" is a
description of a technology, which can be achieved to varying degrees. A necessary

condition is Ellis' notion of a VE, maintained in at least one sensory modality (typically the
visual). For example, a head-mounted display with wide field of view, and at least head
tracking would be essential. The degree of immersion is increased by adding additional and
consistent modalities, greater degree of body tracking, richer body representations, decreased
lag between body movements and resulting changes in sensory data, and so on. Astheimer
defines immersion as the feeling of a VR user, that his VE is real. Analogously to Turing's
definition of artificial intelligence: if the user cannot tell, which reality is "real", and which
one is "virtual", then the computer generated one is immersive.
2.2 VIRTUAL REALITY TIMELINE
Morton Heilig wrote in the 1950s of an "Experience Theater" that could encompass all the
senses in an effective manner, thus drawing the viewer into the onscreen activity. He built a
prototype of his vision dubbed the Sensorama in 1962, along with five short films to be
displayed in it while engaging multiple senses (sight, sound, smell, and touch). Predating
digital computing, the Sensorama was a mechanical device, which reportedly still functions
today. In 1968, Ivan Sutherland, with the help of his student Bob Sproull, created what is
widely considered to be the first Virtual Reality and Augmented Reality (AR) Head Mounted
Display (HMD) system. It was primitive both in terms of user interface and realism, and the
HMD to be worn by the user was so heavy it had to be suspended from the ceiling, and the
graphics comprising the virtual environment were simple wireframe rooms. The formidable
appearance of the device inspired its name, The Sword of Damocles. Also notable among the
earlier hypermedia and virtual reality systems was the Aspen Movie Map, which was created
at MIT in 1977. The program was a crude virtual simulation of Aspen, Colorado in which
users could wander the streets in one of three modes: summer, winter, and polygons. The first
two were based on photographs – the researchers actually photographed every possible
movement through the city's street grid in both seasons – and the third was a basic 3-D model
of the city. In the late 1980s the term "virtual reality" was popularized by Jaron Lanier, one
of the modern pioneers of the field. Lanier had founded the company VPL Research in 1985,
which developed and built some of the seminal "goggles n' gloves" systems of that decade.

CHAPTER 3
Virtual Reality Technology
3.1 Head-Mounted Display
The head-mounted display (HMD) was the first device providing its wearer with an
immersive experience. Evans and Sutherland demonstrated a head-mounted stereo display
already in 1965. It took more then 20 years before VPL Research introduced a commercially
available HMD, the famous "Eye Phone" system (1989).
They are designed to take advantage of human binocular vision capabilities and present the
general following characteristics:
• Headgear with two small LCD color screens, each optical channeled to one eye, for
binocular vision.
• special optics in front of the screens, for wide field of view
• a tracking system for precise location of user head
Fig 3.1:- A head-mounted display (HMD)

A typical HMD houses two miniature display screens and an optical system that channels the
images from the screens to the eyes, thereby, presenting a stereo view of a virtual world. A
motion tracker continuously measures the position and orientation of the user's head and
allows the image generating computer to adjust the scene representation to the current view.
As a result, the viewer can look around and walk through the surrounding virtual
environment.
To overcome the often uncomfortable intrusiveness of a head-mounted display, alternative
concepts (e.g., BOOM and CAVE) for immersive viewing of virtual environments were
developed.
3.2 BOOM
The BOOM (Binocular Omni-Orientation Monitor) from Fakes pace is a head-coupled
stereoscopic display device. Screens and optical system are housed in a box that is attached
to a multi-link arm. The user looks into the box through two holes, sees the virtual world, and
can guide the box to any position within the operational volume of the device. Head tracking
is accomplished via sensors in the links of the arm that holds the box.
Fig 3.2:- The BOOM, a head-coupled display device

3.3 CAVE
The CAVE(TM) is a multi-person, room-sized, high-resolution, 3D video and audio
environment. It was developed at University of Illinois and is available commercially
through Pyramid Systems Inc.
Currently, four projectors are used to throw full-color, computer generated images onto three
walls and the floor (the software could support a 6 wall CAVE.) CAVE software
synchronizes all the devices and calculates the correct perspective for each wall. In the
current configuration, one Rack Onyx with 2 Infinite Reality Engine Pipes is used to create
imagery for the four walls. In the CAVE all perspectives are calculated from the point of
view of the user. Ahead tracker provides information about the user's position. Offset images
are calculated for each eye.
Fig 3.3:- CAVE system (schematic principle)
3.4 Data Gloves
Hand measurement devices must sense both the flexing angles of the fingers and the position
and orientation of the wrist in real-time. The first commercial hand measurement device was
the Data Glove from VPL Research. The Data Glove (Figure 3.4) consists of a lightweight
nylon glove with optical sensors mounted along the fingers.

Fig 3.4:- Data Gloves
In its basic configuration, the sensors measure the bending angles of the joints of the thumb
and the lower and middle knuckles of others fingers, and the Data Glove can be extended to
measure abduction angles between the fingers. Each sensor is a short length of fiber optic
cable, with a light-emitting diode (LED) at one end and a phototransistor at the other end.
When the cable is flexed, some of the LED's light is lost, so less light is received by the
phototransistor. Attached to the back is a Polhemus sensor to measure orientation and
position of the gloved hand. This information, along with the ten flex angles for the knuckles
is transmitted through a serial communication line to the host computer.
3.5 3D mouse and Space Ball
The Logitech 3D mouse is based on a ultrasonic position reference array, which is a tripod
consisting of three ultrasonic speakers set in a triangular position, emits ultrasonic sound
signals from each of the three transmitters. These are used to track the receiver position,
orientation and movement. It provides proportional output in all 6 degrees of freedom: X, Y,
Z, Pitch, Yaw, and Roll.
Spatial Systems designed a 6 DOF interactive input device called the SpaceBall. This is
essentially a “force” sensitive device that relates the forces and torques applied to the ball

mounted on top of the device. These force and torque vectors are sent to the computer in real
time where they are interpreted and may be composited into homogeneous transformation
matrices that can be applied to objects.
Fig 3.4 3D mouse Ball
3.6 Midi keyboards
MIDI keyboards have been first designed for music input, but it provides a more general way
of entering multi-dimensional data at the same time. In particular, it is a very good tool for
controlling a large number of DOFs in a real-time animation system. A MIDI keyboard
controller has 88 keys, any of which can be struck within a fraction of second. Each key
transmits velocity of keystroke as well as pressure after the key is pressed.

CHAPTER 4
IMMERSIVE AND NON IMMERSIVE TECHNOLOGY
4.1 Characteristics of Immersive VR
The unique characteristics of immersive virtual reality can be summarized as follows:
• Head-referenced viewing provides a natural interface for the navigation in three-
dimensional space and allows for look-around, walk-around, and fly-through
capabilities in virtual environments.
• Stereoscopic viewing enhances the perception of depth and the sense of space.
• The virtual world is presented in full scale and relates properly to the human size.
• Realistic interactions with virtual objects via data glove and similar devices allow
for manipulation, operation, and control of virtual worlds.
• The convincing illusion of being fully immersed in an artificial world can be
enhanced by auditory, haptic, and other non-visual technologies.
• Networked applications allow for shared virtual environments (see below).

Fig 4.1:- Types of virtual Reality
4.2 Shared Virtual Environments
In the example illustrated below, three networked users at different locations (anywhere in
the world) meet in the same virtual world by using a BOOM device, a CAVE system, and a
Head-Mounted Display, respectively. All users see the same virtual environment from their
respective points of view. Each user is presented as a virtual human (avatar) to the other
participants. The users can see each other, communicated with each other, and interact with
the virtual world as a team.

Fig 4.2:- Shared Virtual Environment
4.3 Non-immersive VR
Today, the term 'Virtual Reality' is also being used for applications that are not fully
immersive. The boundaries are becoming blurred, but all variations of VR will be important
in the future. This includes mouse-controlled navigation through a three-dimensional
environment on a graphics monitor, stereo viewing from the monitor via stereo glasses,
stereo projection systems, and others. Apple's QuickTime VR, for example, uses photographs
for the modeling of three-dimensional worlds and provides pseudo look-around and walk-
through capabilities on a graphics monitor.
4.4 Virtual Reality Modeling Language
Most exciting is the ongoing development of VRML (Virtual Reality Modeling Language)
on the World Wide Web. In addition to HTML (HyperText Markup Language), that has
become a standard authoring tool for the creation of home pages, VRML provides three-
dimensional worlds with integrated hyperlinks on the Web. Home pages become home
spaces. The viewing of VRML models via a VRML plug-in for Web browsers is usually
done on a graphics monitor under mouse-control and, therefore, not fully immersive.
However, the syntax and data structure of VRML provide an excellent tool for the modeling

of three-dimensional worlds that are functional and interactive and that can, ultimately, be
transferred into fully immersive viewing systems. The current version VRML 2.0 has
become an international ISO/IEC standard under the name VRML97.
4.5 Virtual related technology
Other VR-related technologies combine virtual and real environments. Motion trackers are
employed to monitor the movements of dancers or athletes for subsequent studies in
immersive VR. The technologies of 'Augmented Reality' allow for the viewing of real
environments with superimposed virtual objects. Telepresence systems (e.g., telemedicine,
telerobotics) immerse a viewer in a real world that is captured by video cameras at a distant
location and allow for the remote manipulation of real objects via robot arms and
manipulators.
CHAPTER 5
APPLICATION
There has been increasing interest in the potential social impact of new technologies, such as
virtual reality (as may be seen in utopian literature, within the social sciences, and in popular
culture). Perhaps most notably, Mychilo Stephenson Cline, in his book, Power, Madness,

and Immortality: The Future of Virtual Reality, argues that virtual reality will lead to a
number of important changes in human life and activity. He argues that:
• Virtual reality will be integrated into daily life and activity and will be used in very
human ways.
• Techniques will be developed to influence human behavior, interpersonal
communication, and cognition (i.e., virtual genetics).
• As we spend more and more time in virtual space, there will be an gradual “migration
to virtual space,” resulting in important changes in economics, worldview, and
culture.
• The design of virtual environments may be used to extend basic human rights into
virtual space, to promote human freedom and well-being, and to promote social
stablity as we move from one stage in socio-political development to the next.
5.1 Television
The first major television series to showcase virtual reality was Star Trek: The Next
Generation. They featured the holodeck, a virtual reality facility, generally on star ships and
star bases, that enabled its users to recreate and experience anything they wanted. One
difference from current virtual reality technology, however, was that replicators and
transporters were used to actually create and place objects in the holodeck, rather than relying
solely on the illusion of physical objects, as is done today.
5.2 Motion Pictures
Steven Lisberger's film TRON was the first mainstream Hollywood picture to explore the
idea, which was popularized more recently by the Wachowski brothers in 1999's The Matrix.
The Matrix was significant in that it presented virtual reality and reality as often overlapping,
and sometimes indistinguishable. Cyberspace became something that most movies
completely misunderstood, as seen in The Lawnmower Man and Hackers (film). Also, the
British comedy Red Dwarf utilized in several episodes the idea that life (or at least the life
seen on the show) is a virtual reality game. This idea was also used in Spy Kids 3-D: Game
Over.

The popular classic of The Matrix is about the world of the future, where most of the human
species is kept docile by a race of sentient machines (which humankind created) in a "Virtual
Reality" computer program called The Matrix. The machines use their human population as
energy generators feeding off them as their brains act out their lives completely oblivious of
the real world while inside the Matrix.
5.3 Games
In the Mage: The Ascension role-playing game, the mage tradition of the Virtual Adepts is
presented as the real creators of VR. The Adepts' ultimate objective is to move into virtual
reality, scrapping their physical bodies in favour of improved virtual ones. Also, the .hack
series centers around a virtual reality video game.
5.4 Education and training systems
Education and training is one of the most promising application areas for virtual reality
technologies. Computerized three dimensional atlases presenting different aspects of the
anatomy, physiology, and pathology as a unified teaching atlas are about to revolutionize the
teaching of anatomy to medical students and the generalpublic.
5.5 Medical applications
In the past decade medical applications of virtual reality technology have been rapidly
developing, and the technology has changed from a research curiosity to a commercially and
clinically important area of medical informatics technology. Research and development
activity is well summarized by the yearly "Medicine Meets Virtual Reality" meetings, and the
commercialization of the technology is already at an advanced stage.

5.6 Diagnostics
Initially, algorithms for graphical rendering of anatomy have been used to provide support for
three dimensional organ reconstructions from radiological cross sections. For the clinician
this method of visualizations provided a more natural view of a patient's anatomy without
losing the see through capability of theradiologist.
Virtual endoscopy techniques (such as virtual colonoscopy or bronchoscopy) based on the
virtual reconstruction and visualizations of individual patient anatomy are rapidly developing.
Owing to the potential benefits of patient comfort and cost effectiveness virtual endoscopic
procedures could replace real endoscopic investigations in the foreseeable future in some
areas of diagnosis. The most impressive development has been demonstrated in virtual
colonoscopy as a screening tool for colon polyps and cancer and which is currently in the
clinical validation phase.
5.7 Doctors getting trained in Virtual Hospital
Education and training is one of the most promising application areas for virtual reality
technologies. Medical students will be able to learn real world practical problem in VR
world. For example Medical students can operate a patient who will be dying due to a certain
disease in a VR world and even medical students can get knowledge about emergencies an
accident.
CHAPTER 6
FUTURE SCOPE
6.1 Google Cardboard
Google Cardboard is a virtual reality (VR) and augmented reality (AR) platform developed
by Google for use with a head mount for a mobile phone. Named for its fold-out cardboard
viewer, the platform is intended as a low-cost system to encourage interest and development
in VR and AR applications. Users can either build their own viewer from simple, low-cost
components using specifications published by Google, or purchase one manufactured by a

third-party. The platform was created by David Coz and Damien Henry, Google engineers at
the Google Cultural Institute in Paris, in their 20% "Innovation Time Off". It was introduced
at the Google I/O 2014 developers conference for Android devices, with a release to iOS at
the following year's event. Through January 2016, over 5 million Cardboard viewers had
shipped and over 1,000 compatible applications had been published
Google provides two software development kits for developing Cardboard applications, both
using OpenGL: one for Android using Java, and one for the game
engine Unity using C#. After initially supporting only Android, Google announced iOS
support for the Unity plugin in May 2015 at the Google I/O 2015 conference. Third-party
apps with Cardboard support are available on the Google Play store and App Store for iOS.
In addition to native Cardboard apps, there are Google Chrome VR Experiments
implemented using WebGL; phones, including Apple's, that support WebGL can run
Google's web experiments. In January 2016, Google announced that the software
development kits would support spacial audio, a virtual reality effect intended to simulate
the Doppler effect.
Fig 6.1:- Google Cardboard
6.2 Oculus Rift
The Rift is a virtual reality headset developed by Oculus VR. It was initially proposed in
a Kick starter campaign, during which Oculus VR (at the time an independent company)
raised US$2.5 million for the development of the product.
The Rift is scheduled for release on March 28, 2016, making it one of the first consumer-
targeted virtual reality headsets. It has a resolution of 1080×1200 per eye, a 90 Hz refresh
rate, and a wide field of view. It has integrated headphones which provide a 3D audio effect.
The Rift has rotational and positional tracking. The positional tracking is performed by a

USB stationary IR sensor, which normally sits on the user's desk, allowing for using the Rift
while sitting, standing, or walking around the same room.
The Rift has gone through various prototype versions in the years since the Kickstarter
campaign, around 5 of which were demonstrated to the public. Two of these prototypes were
made available for purchase as 'development kits', DK1 in late 2012 and DK2 in mid 2014, to
give developers a chance to develop content in time for the Rift's release. However, both
were also purchased by a large number of enthusiasts who wished to get an early preview of
the technology
Fig 6.2:- Oculus Rift
CHAPTER 7
CONCLUSION
A virtual environment can represent any three-dimensional world that is either real or
abstract. This includes real systems like buildings, landscapes, underwater shipwrecks,
spacecrafts, archaeological excavation sites, human anatomy, sculptures, crime scene
reconstructions, solar systems, and so on. Of special interest is the visual and sensual

representation of abstract systems like magnetic fields, turbulent flow structures, molecular
models, mathematical systems, auditorium acoustics, stock market behavior, population
densities, information flows, and any other conceivable system including artistic and creative
work of abstract nature. These virtual worlds can be animated, interactive, shared, and can
expose behavior and functionality.
In order to keep pace with real-time interaction, virtual reality technology must be supported
by high performance computers, the associated software and high bandwidth network
capabilities. Virtual reality also requires the development of new technologies such as
displays that update in real-time with head motion; advances in sensory feedback such as
force, touch, texture, temperature, and smell; and intelligent models of environments.
As the technologies of virtual reality evolve, the applications
of VR become literally unlimited. It is assumed that VR will reshape the interface between
people and information technology by offering new ways for the communication of
information, the visualization of processes, and the creative expression of ideas.
REFERENCE
1) Beier Peter,Virtual Reality:A short introduction,http://www-vrl.umich.edu
2) John Vince,Virtual Reality Systems,Addison-Wesley.
3) Rory Stuart,The Design Of Virtual Envoirnment,Barricade Books.

4) John Vince,Essential Virtual Reality Fast :How to understand the techniques and potential
of Virtual Reality,Springer Verlag.
5) Jed Hartman,Josie Wernecke,Rick Carey,The VRML 2.0 Handbook – Building Moving
World on the Web,Addison-Wesley.

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