Transcript Augmented Reality - Itprojectsforyou

Contents
1. Introduction
2. Virtual Reality (VR)
3. VR v/s AR
4. Need for Augmented Reality (AR)
5. Design
6. Challenges
7. Applications
8. Future Prospects
9. Conclusion
10. References
2
1. Introduction
Augmented Reality :
An Augmented Reality system generates a
composite view for the user. It’s a combination of the
real scene viewed by the user and a virtual scene
generated by the computer that augments the scene
with additional information.
AR systems have the following three properties:
Blends real and virtual, in real environment
2. Interactive in real time
3. Registered in 3D
1.
3
1.1 AR View
4
2. Virtual Reality (VR)
 “A computer generated, interactive, three-
dimensional environment in which a person is
immersed.”
 Requires high performance computer graphics to
provide an adequate level of realism
 Blocks out all the external world and present to the
wearer a view that is under the complete control of
the computer
5
3. VR v/s AR
Virtual Reality
 Totally immersive
environment.
 Completely immersed in
an artificial world and
becomes divorced from
the real environment
 Visual senses are under
control of system
Augmented Reality
 System augments the
real world scene
 User maintains a sense
of presence in real
world
 Needs a mechanism to
combine virtual and real
worlds
6
3.1 Reality-Virtuality Continuum
Milgram’s Reality-Virtuality Continuum
The real world and a totally virtual environment are at
the two ends of this continuum with the middle region
called Mixed Reality.
Augmented Virtuality -> systems which are mostly
synthetic with some real world imagery
7
4. Need for AR
 For some applications, it may be desirable to use as
much as possible real world in the scene rather
creating a new scene using computer imagery. Eg.
Medicine and telerobotics
 Can maintain the high-level of detail and realism that
one finds in the real world.
 AR enhances real world, while VR replaces or
simulates the real world
8
5. Design
The four components of any AR system are
5.1
5.2
5.3
5.4
The Display System (usually an HMD)
The Tracking System
Mobile Computing Power
Input device (usually a wrist mounted keyboard)
9
5.1 The Display System
 Allows the user to see the image and text created by
the Augmented Reality Systems
There are basically two types of display systems:
5.1.1 Optical see-through
5.1.2 Video see-through
5.1.1 Optical see-through displays
• Direct viewing of real world through naked eye
• Uses optical combiners- partially reflective, partially
transmissive
• Similar to HUDs used in military aircrafts
10
5.1.1 Optical see-through display
11
5.1.2 Video see-through display
 Combination of closed-view HMD and one or more
head-mounted video cameras
 Video from camera combined with graphic images
created by the scene generator
12
Advantages of Optical see-through display
 Simplicity- cheap and simple (one video stream).
 Resolution- user’s real world view is not retarded
 Safety
 No eye offset
Advantages of Video see-through display
 Flexibility in composition strategies
 Wide field of view
 Real and virtual view delays can be matched
 Additional registration strategies
 Easier to match brightness of real and virtual objects
13
5.2 The Tracking System
 Used to find the position and orientation of the viewer
 Where the user is located with respect to his surroundings
 Movement of user’s head
The two main functions of tracking system:
 Find the person’s position in space
 Using
the three Cartesian coordinates- x, y and z
 Find the direction in which the person is looking
 Using three angles- pitch(or elevation), roll and yaw(azimuth)
These are called six degrees of freedom (DOF)
14
Tracking System (contd)
The six degrees of freedom
•Positive pitch- upward head tilt
•Positive roll- left head tilt
•Positive yaw- left head rotation
2 conventional tracking devices used:
 Hi-ball Tracking System(for indoor applications)
 GPS (for outdoor applications)
15
5.3 Mobile Computing Power
 Ideal computing device – wearable computers
 Freedom in movement
 Ergonomics
 Ruggedness (depends on the application)
Features:
 Portable while operational
 Hands-free use
 Attention getting
 Always ON
16
Mobile Computing Power (contd)
 HMD
 CPU module
 Wrist-mounted Keyboard
Eg. Xybernaut Wearable Computer
17
6. Challenges/Design Issues
6.1 Display Issues
 Focus and contrast
 Eye offset
 Field of view
6.2 Registration Issues
6.3 Tracking Issues
 Sample rate
 Update rate
 Latency
6.4 Portability Issue
18
6.2 Registration Issues
6.2.1 Static Errors
 Optical Distortions
 Mechanical misalignments
 Incorrect viewing parameters(FOV, interpupillary dist.)
6.2.2 Dynamic Errors
 System lag (latency)
19
6.3 Tracking Issues
 Sample rate- rate at which sensors are checked for data
 Update rate- The rate at which the system reports new
position coordinates to the host computer
 Latency(or lag)- delay between the movement of the remotely
sensed object and the report of the new position
6.4 Portability Issue
 The user moves around
 Ergonomics (when mounted and used for a long duration)
 The power consumption should also be at minimum since
the system is to run on batteries to facilitate portability
20
7. Applications
7.1 Medical
 Training aid – Virtual instructions for a novice surgeon
 Surgery – ultrasound imaging
7.2 Manufacturing and repair
 Machine assembly – Instructions as 3-D drawings
superimposed upon the actual equipment
7.3 Military
 BARS- Battle Field Augmented Reality System
 Military Aircrafts-HUDs and HMSs
7.4 Annotation and Visualization
 Used in sports – to name or point out cars in a race
7.5 Entertainment
 Games – the most recent one being an AR version of
the popular game Quake- ARQuake
21
7.1 Applications: Medicine
A tumor surgery
Laparoscopy
22
7.2 Applications: Manufacture/Repair
BARS
Laser Printer Assembly
7.3 Applications: Military
23
7.4 Applications: Annotation
24
8. Future Prospects
AR has a wide vista of applications in store for future:
 Medical: In minimal invasive surgeries, endoscopy,
laparoscopy
 Collaborative Applications: Military- BARS
 Commercial Applications: Ads, games and sports-Race
F/X
 Tourism: ARCHEOGUIDE- helps tourists with info.
Implemented in Greece on a test basis.
 Multimodal displays (haptics and auditory interactions)
25
9. Conclusion
AR systems are far behind VR systems in terms of
maturity. Augmented Reality is a relatively new field, where
most of the research efforts have occurred in the past few
years. Because of the numerous challenges and
unexplored avenues in this area, AR will remain a vibrant
area of research for at least the next several years.
After the basic problems with AR are solved, the ultimate
goal will be to generate virtual objects that are so realistic
that they are virtually indistinguishable from the real
environment.
26
10. References
[1] Ronald T. Azuma, “A Survey of Augmented Reality”, PresenceTeleoperators and Virtual Environments, Volume 6, pp. 355-385,
1997
[2] Ronald T. Azuma, Yohan Baillot, Steven Feiner, Simon Julier,
“Recent Advances in Augmented Reality”, IEEE Computers Graphics
& Applications, Volume 21, November 2001
[3] Claudio Kimer,Ezequiel R. Zorzal, Tereza G. Kirner, “Case Studies
on the Development of Games Using Augmented Reality”, IEEE
International Conference on Systems, Man and Cybernetics, October
2006
[4] Lyu M. R, King I, Wong T. T, “ARCADE: Augmented Reality
Computing Arena For Digital Entertainment”, Aerospace Conference
2005
27
THANK YOU…..
28