Presentation on Augmented Reality done as part of my seminar. Covers comparison of AR, VR, implementation of AR, Problems in its implementation etc.

1. SEMINAR
AUGMENTED REALITY
MAHESH M

2. AUGMENTED REALITY(AR)
Attempt to enhance the real world by adding
information about the current object or environment
by means of super imposing visuals, sounds, smells,
haptic.

3. IN THIS PRESENTATION
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Virtualization of and Augmenting the Real World
Augmented reality - Introduction
Implementation
AR in Mobile devices
challenges or Problems
Applications

4. VIRTUAL REALITY
• Replaces the reality
entirely with computer
generated world

5. VR - Common practises and Applications
• Usually projected on a screen or on a stereoscopic
display
• Mainly used in entertainment sector such as film,
gaming, treatment,etc.
• In most cases, just recreates the world.
But now incorporates audio of the environment
and also haptics to feel the touch/ interaction with
the objects.

6. AR
• HISTORY
– Ivan Sutherland’s vision of AR
User is “inside” the computer
– 1965 "Ultimate Display"
Real and synthetic objects coexist
– 1968 “Head Mounted Display” AR System
(MIT, Harvard, Univ. of Utah)
Graphics (vector mono)
HMD (optical see-through)
Tracker (mech. on head)

7. AR
• Now...
– Moore's law
• more processing power in smaller sizes and
advanced graphic generators
– Displays
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HMD
LCD
Laser
OLED
See through displays
etc.

8. AR
• Now...
– New algorithms and technologies
• Advanced tracking systems such as
GPS/RF,Optical IR, ultrasonic etc.
• New ways of interacting with the world like voice
commands, gesture support etc.
• Smarter devices - displays contents/information
automatically from around the world, according to
the need of the user

9. IMPLEMENTATION
Most Important building blocks of an Augmented
Reality System are
– Processor
– Display
– Tracking device
– Human Interaction Device

10. Processor
• The system can be a individual
device/embedded system, based on some
processor
• Usually processing done in a PC or some
other kind of mobile device such as smart
phones, tablets etc.
• In the former case, device size gets reduced
in a great amount and becomes more
powerful with the advances in IC
technologies

11. Processor
• Second case – processing done on another
device
– Sensors either embedded on the device(as in
smartphone/tablets) or are connected
separately to the device

12. Displays
• most of the AR systems augments the real world
with visuals rather than using sounds or other
senses
• Several display technologies classified into
– Head worn displays
– Handheld displays
– projection displays

13. Displays - Head worn
• mounted on head
• two types
– optical see through
• provides AR overlay through a transparent display
• Have a disadvantage of insufficient brightness
– Video see through
uses video captured from head mounted cameras to
provide background on an opaque screen

14. Displays - Head worn
Another approach
Virtual retinal display
– visuals drawn directly on retina using low
power modulated laser beams which are
scanned by micro electromechanical mirror
assemblies that sweep the beam horizontally
and vertically

15. Displays - Head worn
• An example for optical
see through approach
– using prism technology
• visuals projected towards
the glass which are then
projected into the eyes
using prism arrangement
• Advantage - can be created
on usual eyewears

16. Displays - Handheld
• Uses handheld flatpanel LCD/(O)LED displays
with a camera which captures the images
process and augments it and provide video see
through augmentation

17. Displays - Projection type
•Virtual information projected
directly on the physical object
to be augmented
•No need for special eye
wears
•Can be projected from a
single room mounted
projector or from a head
mounted portable projector
for mobility

18. Displays - Projection type
• Another interesting application - Optical
camouflage

19. Tracking Device
• To track the user's orientation and position
Eg.: Magnetic and video sensors
• To get more accurate registration - hybrid
sensors (accelerometer + video sensors)
• For improved tracking performance - Single
Constraint At A Time(SCAAT) Algorithm

20. TRACKING - USING GPS, GSM, UMTS
• Most commonly used - GPS for its low cost and
sufficient accuracy of about 3-10m / 2-5m for
differential GPS(DGPS)
• GSM/UMTS - upcoming solution
– locate by triangulating signals of the mobile
phone
– less accurate

21. TRACKING - OTHER METHODS
• Outside in and inside out tracking
– outside in - tracking the user with an external
camera, ie., imaging sensor mounted outside
the tracking space
• more accurate
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– inside out - imaging sensor mounted on head
Visual marker based tracking
Visual markerless tracking
Sensor Based tracking
Wireless-LAN based tracking
Hybrid tracking systems

22. Environment sensing
• Needs to locate other objects around the user
• For indoor cases use cameras and object
markers
• for outdoor/unprepared situations
– a hybrid compass/gyroscope tracker provides
motion stabilized orientation measurements
– adding video tracking increses the accuracy
– GPS - track real time position
• limitation - need clear view of sky

23. Human Interface device
• Lets the users interact with the augmented
environment
• Different technologies such as interaction
through gesture, voice etc. and haptic feedback
to let the user feel the interaction

24. Audio Augmented Reality
• Can be achieved using Spatialized audio
• postion can tracked using gyros or magnetic
compasses
• helpful for blind navigation or when the user is
concentrating on another activity

25. Mobile Augmented Reality Systems - MARS
• One of the area that is being popular nowadays
• Computing hardwares - Handheld mobile
devices or wearable devices
• Tracking - Integrated GPS, Gyroscopes,
accelerometers and cameras

26. Wireless networking in MARS
Wireless networking
– improves performance and quality of user
experience
– enhances mobility
For a Usable AR wireless network should provide
– sufficient data rate
– low latency
– support for mobility

27. Wireless Wide Area Networks
• ideal for systems that need large scale mobility
Example:
• Several choices from low speed(9.6Kbps) to
high speed 3G networks(upto 2Mbps)
• 2G mostly used - but limitted due to their low
speed and high latency
• 2.5G or GPRS - speed upto 171.2Kbps - also
suffer from high latency
• Highly interactive AR sysems need lower
latencies of less than 100ms

28. Wireless Wide Area Networks
• 3G or Universal Mobile Telecomunication
System(UMTS) - speed upto 2Mbps(theoretical)
» nearly 300Kbps practically
• round trip time/latency ~ 300-580ms => prevents
real time VR/AR

29. Wireless Local Area Networks (WLANs)
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networks implemented in a local area
speed in the range of 11-54Mbps
low latency than WWAN
typical range - 100m
Mainly used in gaming etc.

30. Wireless Personal Area Networks(WPANs)
• Short range
• Implemented using Bluetooth,infrared etc.
• Used for controlling the VR environment

31. CHALLENGES
A good AR should convince the user that the
virtual and the real worlds coexists.
This is a diffcult task. Problems arrive while
implementing the display technologies and
processors and also in case of networking in
MARS.

32. CHALLENGES - DISPLAYs
• various issues
– technological - latency, resolutiondistortion,field of view, and cost
– perceptual - depth of field, qualitative
– human factors - social acceptance and safety
• Optical see through displays :
– have all the above technological issues
– parallax error - since cameras mounted away
from true eye location
• Registration error

33. APPLICATIONS
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Medical
Entertainment
Personal assistant
Navigation
Blind assistant
etc.

34. Case study - Googe Glass

35. Case Study - 6th Sense technology

36. References
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Wagner, Daniel, et al. "Real-time detection and tracking for augmented
reality on mobile phones." Visualization and Computer Graphics, IEEE
Transactions on 16.3 (2010): 355-368.
•
Blum, Jeffrey R., Mathieu Bouchard, and Jeremy R. Cooperstock. "What’s
around me? Spatialized audio augmented reality for blind users with a
smartphone." Mobile and Ubiquitous Systems: Computing, Networking, and
Services. Springer Berlin Heidelberg, 2012. 49-62.
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Azuma, Ronald, et al. "Recent advances in augmented reality." Computer
Graphics and Applications, IEEE 21.6 (2001): 34-47.
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Papagiannakis, George, Gurminder Singh, and Nadia Magnenat‐Thalmann.
"A survey of mobile and wireless technologies for augmented reality
systems."Computer Animation and Virtual Worlds 19.1 (2008): 3-22.

37. THANKS