An Integrated Approach to the Study of Virtual Environments

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					    International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012                                          ISSN 2278-6856




             An Integrated Approach to the Study of
                     Virtual Environments
                                           K.Merriliance1, Dr M.Mohamed Sathik2
                                               1
                                              Sarah Tucker College(Autonomous), India,.
                                           2
                                            Sadakkathulla Appa College(Autonomous),India,

                                                                  only on your computer screen, or through a special
Abstract: Virtual Environment is aimed at providing               headset or visor, opens the door for an incredible variety
nonprogrammers with an easy-to-use 3D “What-You-See-Is-           of experiences. It adds the ability to navigate through a
What-You-Get” environment. It allows users to view and            virtual environment or the capability of picking up
interact with objects displayed on a workspace similar to a       objects, or otherwise interacting with objects found in the
tabletop workspace used in day-to-day life. The major             virtual environment, and the basis for the enthusiasm for
challenge in these interfaces is to adopt 2D devices such as      the technology becomes readily apparent. VEs provide an
mouse and keyboard to perform 3D tasks, e.g. navigation. In
                                                                  environment where 3D visualization objects can be
this paper We discuss about an integrated approach to the
                                                                  viewed in their native three dimensions that give the
study of various virtual Environments. These analytical
studies provide distinct advantages in terms of ease of use and
                                                                  users an opportunity to gain a more complete
efficiency because they consider the tasks of Virtual             understanding of these complex objects. In addition, the
Environments separately and investigated the performance of       ability to manipulate the data in an intuitive manner,
three virtual environments: immersive, non immersive and          move through the virtual world, and move around these
Desktop VE.                                                       complex objects allows users to focus their attention on
Keywords: virtual Environments,             Immersive     VE,     the data and away from the interface. They are primarily
Desktop VE, Virtual reality.                                      visual experiences, displayed either on a computer
                                                                  screen or through special or stereoscopic displays, but
1. INTRODUCTION                                                   some simulations include additional sensory information,
                                                                  such as sound through speakers. Users can interact with a
Visualization is the ability to present complex data as
                                                                  virtual environment either through the use of standard
multidimensional images and combined with direct
                                                                  input devices such as a keyboard and mouse, or through
control over that data in VR. In a VR environment the
                                                                  multimodal devices such as a wired glove or the HMD.
data is presented truly in 3D and users can interact with
                                                                  The simulated environment can be similar to the real
the data directly in the 3D space. The advance of
                                                                  world, for example, simulations for pilot or combat
computer graphics knowledge and technology, itself tied
                                                                  training.
to the enormous increase in processing power          and
decrease in cost, together with the development of
relatively efficient and unobtrusive sensing devices, has
led to the emergence of participatory immersive virtual
environments(VE), commonly referred to as "virtual
reality"[3].The concept of virtual Reality is a three-
dimensional, computer-generated environment that
allows for single or multiple users to interact navigate,
respond, and experience a synthesized world modeled
from the real world. Virtual environment is a high-end
user-computer interface that involves real time simulation                     Figure 1: Virtual Environment
and interaction through multiple sensorial channels. It           Virtual environments are also used to reduce phobias, to
incorporates the interaction within a VE or virtual world         develop skills, and to train those with disabilities.
by the help of various peripheral devices in order to             "Virtual environments as interactive, virtual image
achieve a multi-sensory and multi-modal experience.               displays enhanced by special processing and by non visual
Although virtual reality has been popularized as a new            display modalities, such as auditory and haptic, to
form of entertainment, it has applications in business,           convince users that they are immersed in a synthetic
industry, and medicine. Virtual reality also has practical        space”. Virtual environments provide an effective way to
applications in business, manufacturing, and medicine.            optimize performance when people interact with virtual
                                                                  environments. Figure1 illustrate the working Virtual
 2. VIRTUAL ENVIRONMENT                                           Environment. VE can be classified into Desktop VE, Non
                                                                  immersive VE and Immersive VE
Virtual Environment is a computer-generated, interactive,            2.1 Desktop VE
three-dimensional environment in which a person is
immersed. The ability to navigate through a world seen

Volume 1, Issue 2 July-August 2012                                                                                Page 247
   International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012                                          ISSN 2278-6856


Desk-top virtual reality is a computer programs that will      figures, holograms, disguised objects, optical illusions, etc
support a user-friendly interface for complex data             environment - a room, a simulator, etc. - where normal
processing and simulation procedures, including image          sensory cues are not cut off, but are supplemented by
processing and real time 3D visualization. Although they       additional sounds, images, or other sensations. The
lack the immersion quality, they consist of computer-          advantage of this type of VR is that it can be a communal
generated environments which exist in 3 dimensions.            experience, with many people participating at once. In a
Desktop VR is used to see a stereoscopic 3D view, on a         sophisticated enough environment, it might be difficult to
regular monitor, through the use of special software.          determine who the "real" participants are. Non-immersive
Because the worlds exist in 3 dimensions, users can freely     systems, as the name suggests, are the least immersive
navigate in 3 dimensions around in the worlds. Ex: Flight      implementation of VR techniques. Using the desktop
simulators where participants “fly” though models of real      system, the virtual environment is viewed through a
or fantasy worlds, watching the world on a 2-D screen.         portal or window by utilizing a standard high resolution
2D interaction can also be regarded as a normal desktop        monitor. The boundaries are becoming blurred but all
system enhanced with 3D functionality. This implies that       variations of VR will be important in the future. This
we can still use the common 2D desktop input devices as        includes mouse controlled navigation through a three
the keyboard and mouse [7]. In desktop virtual                 dimensional Environment on a graphics monitor via
environments (VEs), there are still limitations on the         stereo glasses stereo projection systems and others.
number of objects that can be programmed to be                 Interaction with the virtual environment can occur by
interactive, usually due to restrictions on programming        conventional means such as keyboards, mice and
time and cost.                                                 trackballs or may be enhanced by using 3D interaction
                                                               devices such as a Space Ball or Data Glove.             The
                                                               advantage of this type of VR is that it can be a communal
                                                               experience, with many people participating at once. In
                                                               this environment, they remain themselves, participating
                                                               in their own quite real body, although obviously
                                                               costuming and masquerade may be part of the experience.
                                                               Fig 3 illustrates the Non Immersive Virtual Environment.
                                                               As in immersive VR animation and simulation are
                                                               interactively controlled in response to the user’s direct
                                                               manipulation.[2] System attempts to give the users a
                                                               feeling of being at least slightly immersed by a virtual
         Figure 2: Desktop Virtual Environment                 environment, which is often achieved by different types of
This form of VR completely lacks any feelings of               so called workbenches and reach-in displays.
immersion on the part of the user. The desktop VR
approach does not allow the user to control and
navigation within the virtual environment. It does not
allow multi-user cooperation and communication.
Advantages of Using Desktop VE
      Virtualization is very cheap.
      Mobility and interaction simplicity.
      Realistic, flexible and interactive
      Hardware performance is huge.
      Easily controlled by the user.                               Figure 3: Non Immersive Virtual Environment
      Reliability is very good.                               Advantages of Using Non-Immersive VE
      Reduce risk of exposing sensitive data.                      Do not require the highest level of graphics
                                                                      performance.
      Provides stable and high resolution stereoscopic
          viewing to all participants.                              No special hardware and software.
The users manipulate what is perceived to be “real”                 It is cost-effective
objects in the same manner as they would manipulate                 Easy to develop.
them when you interact in other computer environments               System can be regarded as lower cost VR solution
[9].                                                                  which can be used for many applications.
                                                                    It can be a communal experience, with many
  2.2 NON-IMMERSIVE VE                                                people participating at once
                                                               Non-immersive systems are a relatively new
Non Immersive VE calls 'artificial reality,' requires no       implementation of VR technology and borrow
personal hardware. Rather, the person enters an People         considerably from technologies developed in the flight
participating at once. it can combine quite 'real' objects -   simulation field. Using a wide field of view, these systems
tree, whatever – with 'unreal' ones, such as animatronics      increase the feeling of immersion or presence experienced
Volume 1, Issue 2 July-August 2012                                                                              Page 248
   International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012                                          ISSN 2278-6856


by the user. However, the quality of the projected image is     technologies can now include 3D head-gear with
an important consideration. It is important to calibrate the    stereoscopic vision for look around and walk through,
geometry of the projected image to the shape of the screen      auditory input, voice activation, data gloves and other
to prevent distortions and the resolution will determine        tactile or haptic tools for manipulation and control of
the quality of textures, colors, the ability of define shapes   virtual objects, and even body suits wired with biosensors
and the ability of the user to read text on-screen which are    for advanced sensory input and feedback. A man interacts
more expensive.                                                 with an immersive Environment as shown in Fig 4.
   2.3 Immersive Virtual Environment
Immersion originally depends on visual aspects
implemented by 3D Computer Graphics, as users need to
feel that they are located in a similar to real world. So far
users could see, hear and manipulate objects through VR.
Then the technology develops, users will be able to smell,
taste, touch and feel object through VR in the near future.
Immersion may lead to a sense of presence. This is refers
to the participant's sense of "being there" in the world
created by the VE system. Immersion describes a kind of
technology, and presence describes an associated state of                  Figure 4: Immersive Environment
consciousness. People must carry out everyday activities        Advantages of Using Immersive Environment
in an unnatural or artificial way, for example, moving            The user is provided with a 3600 which means that
through the world by pointing. There is no sense of                the user will receive the usual image if they can turn
peripheral vision, limiting the user's ability to know what        their head to look at any direction.
is happening around them.[5]. A VE is described as                Provide sense of immersion (being there).
immersive when the computer-generated environment                 Provides the users with a richer and deeper
appears to enclose the user, and when the parts of the             experience [12].
physical world are blocked from view. The user has no             Play a crucial role in the determination of presence.
visual contact with the physical world. An                        Specialized 3D Audio used in immersive is
immersive digital environment is an artificial, interactive,       advantage because the system can allow the user to
computer created scene or "world" within which a user              localize sound. That is “home in “on it by turning the
can immerse themselves.                                            head, as one does in the real world.
Immersive digital environments could be thought of as             It will dominate in entertainment and in applications
synonymous with Virtual reality, but without the                   where the users need to wear special equipment
implication that actual "reality" is being simulated. An           (space application and      medical applications)
immersive digital environment could be a model                              Table 1: Summary Comparison
of reality, but it could also be a complete fantasy user
interface or abstraction, as long as the user of the                  Main         Desktop     NonImmersive    Immersive
environment is immersed within it [10]. The definition of            Features        VE            VE            VE
immersion is wide and variable, but here it is assumed to
mean simply that the user feels like they are part of the            Cost of                                      High
                                                                    evaluation       Low         Medium
simulated "universe". The success with which an
immersive digital environment can actually immerse
                                                                    Information                 communal        solipsistic
the user is dependent on many factors such as                                       public      experience
                                                                      Sharing                     (static)     and private
believable 3D computer graphics, surround sound,
interactive user-input and other factors such as simplicity,       Environmen       Static      Static (2D)     Dynamic
                                                                     t Type       (3D to 2D)                     (3D)
functionality and potential for enjoyment. The feeling of
“being there” that is experienced in some VEs. A VE user            Positioning                                   High
is immersed when he feels that the virtual world                     Error rate    medium          low
surrounds him and has to some degree replaced the
physical world as the frame of reference. Immersion may
                                                                                                                  High
take place in other media, such as films or even books.             Interactive
                                                                       skills        Low         Medium
Immersive VR with HMD allows users to focus on display
without distraction. The sense of inclusion within a
virtual world which this technology creates a powerful                                                          Medium
                                                                       Lag           Low           Low            to
personal impact.                                                                                                 High
The fully immersive VR initiated by HMD technology has                                                          Low to
today reached a very high degree of sophistication.                Performance      High           High         Medium
Immersive VE can currently offer a convincing illusion of
participation in a full-scale virtual world.[11] Immersive

Volume 1, Issue 2 July-August 2012                                                                             Page 249
   International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012                                          ISSN 2278-6856


Table 1 shows the characteristics in terms of use and         the comparative study and combines them in a seamless
efficiency because they consider the tasks of Virtual         way to maximize ease of use and efficiency. We plan to
Environments      separately and     investigated   the       continue this analytical study by performing a more
performance of three virtual environments: immersive,         formal experiment using the best of these techniques on
non immersive and Desktop VE. When we analysis these          several specific tasks. It will also be important to
three virtual environments in the view of the sense of        determine in a quantitative and qualitative way the
situational awareness or navigation skills, desktop VE        differences between these Virtual Environments which
was 13% non immersive VE taking 34% and Immersive             have sets of usability Characteristics. Therefore, it is
VE got 53%(shown in Figure 5) .                               important to examine the comparative study that are
                                                              available and determine those that are best suited for the
                                                              tasks that need to be accomplished.

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Immersive Virtual Environment takes the best aspects of

Volume 1, Issue 2 July-August 2012                                                                           Page 250

				
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