Virtual Environments

quartercircleΤεχνίτη Νοημοσύνη και Ρομποτική

14 Νοε 2013 (πριν από 3 χρόνια και 6 μήνες)

63 εμφανίσεις

1

Introduction to

Virtual Environments


User Interfaces and Usability

Fall 09

John Quarles



http://www.youtube.com/watch?v=ctnY2hcHDKc


2

Virtual Reality Definition

What is virtual reality?


Virtual



being in essence or effect, but not in fact

Example VRAM


Reality


the state or quality of being real. Something that
exists independently of ideas concerning it.
Something that constitutes a real or actual thing as
distinguished from something that is merely
apparent.”


What was the first VR?

3

What was the first VR?

4

Progression

Story telling


What did this rely on?

User’s imagination!

Multi
-
sensory


Images


Sounds

Control


Events


View

What do these things have in common?


Immersion

5

Define VR

Burdea:

Virtual reality is a high
-
end user
-
computer
interface that involves real
-
time simulation
and interactions through multiple sensorial
channels. These sensorial modalities are
visual, auditory, tactile, smell, and taste.

6

Burdea’s 3 I’s of VR

Interactivity


user impacts world


Define


Channels

Immersion


believing you are there


Define


What contributes to it?

Imagination


user ‘buying’ into the experience


Examples


Why is this necessary?

7

Ivan Sutherland’s

The Ultimate Display

“Don’t think of that thing as a
screen, think of it as a
window, a window through
which one looks into a virtual
world. The challenge to
computer graphics is to make
that virtual world look real,
sound real, move and
respond to interaction in real
time, and even feel real.”

8

Our definition (from Brooks’ What’s
Real About Virtual Reality)

Virtual Reality Experience


the user is
effectively immersed in a responsive virtual
world.

Implies
-
> user dynamic control of viewpoint


Control becomes an important element of VR
systems.


Differentiates VR from books and movies (or watching
movies in HMD)


Why is control more important?

9

Key Elements of Virtual Reality
Experience

Virtual World
-

content of a given medium


screen play, script, etc.


actors performing the play allows us to
experience the virtual world


Immersion


sensation of being in an
environment


mental immersion


suspension of disbelief


physical immersion


bodily entering the
medium


Related to
presence



(mentally immersed)
the participant’s sensation of being in the
virtual environment (Slater)



http://www.youtube.com/watch?v=h8c6U7dp
I7g


Walking Experiment at

UNC


Chapel Hill

10

Key Elements of Virtual Reality
Experience

Sensory Feedback


information about the
virtual world is presented to the participant’s
senses


Visual (most common)


Audio


Touch

Interactivity


the virtual world responds to the
user’s actions.


Computer makes this possible


Real
-
time

Walking Experiment at

UNC


Chapel Hill

11

Given these points… are these VR
experiences?

Virtual World

Immersion

Sensory Feedback

Interactivity

Create a table and decide how these items stack up as
VR or not:


ZORK


Choose Your Own Adventure


Fallout 3


Transformers (the 2007 movie)


747 Flight Simulator


Microsoft Flight Simulator 2004 (on a PC)


Hitchhikers Guide to the Galaxy (the book)

12

Other Definitions (from book)

Artificial Reality


synthetic environments in
which a user may interactively participate

Virtual


not real. representations of physical
objects.

Virtual World, Virtual Reality, Virtual
Environments



used interchangeably.


Brooks


we aren’t even close to creating realities yet.

Cyberspace


location that exists only in the
mind of the participants. DO NOT OVERUSE or
lower letter grades will result! (kidding)

13

Virtual Environments

Augmented Reality (Mixed Reality)

Telepresence

Artificial Reality

Classical Simulation Environments

Virtual Reality


All Virtual Objects

All Real Objects

14

Augmented (Mixed) Reality

A combination of a
real scene viewed by
a user and a virtual
scene generated by a
computer that
augments the scene
with additional
information.

Ultrasound Visualization Research at

UNC


Chapel Hill

All Virtual Objects

All Real Objects

15

Telepresence


The use of various technologies to
produce the effect of placing the user in
another location.

All Virtual Objects

All Real Objects

16

Artificial Reality
(Myron Kruger)

Responsive Environment

Is an environment where
human behavior is
perceived by a computer
which interprets what it
observes and responds
through intelligent visual
and auditory displays

http://www.youtube.com/
watch?v=dqZyZrN3Pl0


All Virtual Objects

All Real Objects

17

Classical Simulation

Classical simulation is a
mix of real objects and
computer generated
stimuli.

http://www.youtube.com/w
atch?v=ZyLgrKUBfJo


http://www.youtube.com/w
atch?v=4fKf
-
JBCFqE



All Virtual Objects

All Real Objects

18

Virtual Reality

Ideal for VR is that
everything you
experience is
computer
-
generated.



All Virtual Objects

All Real Objects

19

VR usually implies

Immersive Technology


Remember definition

Real
-
time first person view

Environment responds to you (at least at
the level of head
-
motion)

20

Immersive Technology

Head
-
mounted
Display


Optical System


Image Source (CRT or
LCD)


Mounting Apparatus


Earphones


Position Tracker


21

Immersive Technology

Multi
-
screen Projection of
stereoscopic images
(CAVE)

22

Immersive Technology

Single large
stereoscopic display


Projection
-
based


Head
-
tracked


Possible tracking of
hands and arms.


Brings virtual objects
into the physical world

23

Other Characteristics

Head and body tracking implies that visual
content is always computed and rendered
in “real time” (10
-
60 frames/second).

In virtual reality you have a sense of, and
interact with, three
-
dimensional things as
opposed to pictures or movies of things.

24

What are the primary intellectual components
that create a virtual environment?

Hardware / Technology

User’s Perspective (the environment that
is experienced)

System Software Design

Interaction Techniques



25

User’s perspective

Setting

Objects in world

Other participants

Active/Passive


Factory Simulation


Architectural
Walkthrough


26

Hardware / Technology

What is my computation
environment?

How many active users
do I wish to
accommodate?

What display modalities and technologies will
I use?

What sensor modalities and technologies will
I use?

27

System Software Design

Software structures that run the virtual
environment


Rendering group

Graphics, audio, haptic


Sensor polling group

Separately poll each sensor hardware subsystem


Computation group

Manage the state of the environment

28

Interaction Techniques

Do I interact with the
environment?


How do I interact with
the environment?


Not the same as what
devices I use


29

Applications?

Most current applications:

Special Purpose

Interaction simple and/or infrequent

Sidestep limitations of graphics and
haptics

A few expensive systems are sold to a few
rich people

http://video.google.com/videoplay?docid=
-
1997633508821626439&ei=C
-
XUSuXvJJjqqwLHqqnKCg&q=flight+simulator&hl=en&client=firefox
-
a#


30

Entertainment

31

Design Visualization

http://www.youtube.com/watch?v=tISLizgcbLk


http://video.google.com/videoplay?docid=
-
1657678101266526279&ei=bC3XSsC6KYLkrAKO4P
mgCg&q=virtual+manufacturing&hl=en&client=firefox
-
a#docid=
-
2214506601835298077


32

Training (NASA)

http://www.imdb.com/video/wab/vi1541472
793/


33

Clinical Virtual Reality

The direct use of VR as a tool in the treatment or
assessment of psychological and physical
disorders.

Hunter Hoffman

HITLab


University of
Washington

http://www.virtuallybetter.com/environments.html


34

35

Why VR?

In groups


develop a
set of guidelines for
when to apply VR to a
problem

Give three examples
of applications that fit
your definition, and
three examples of
common
misconceptions.