HF 2 Augmented Reality

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Human Factors 2 Augmented Reality

• Characteristics of AR systems
• Applications
• Types of AR
• Issues in AR

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Augmented Reality Characteristics

• Combines real and virtual virtual objects
  superimposed or composited with the real world
  (adding and/or removing)
• Interactive in real time
• Registered in 3-D
• In contrast to VEs, AR supplements reality
  rather than replacing it

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Components of an AR system
NB AR can be applied to all senses. There are
systems that are being developed that can
accommodate sound, in which the user wears
headphones equipped with microphones.
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Why use AR?

• The information conveyed by the virtual objects
  helps the user perform real-world tasks. It
  provides information to the user that is not
  directly available to the users senses
  otherwise.

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Applications

• Medical project non-invasive imaging scans (MRI,
  CT, ultrasound) onto the patients body - x-ray
  vision. Particularly useful for minimally
  invasive surgery. Also for guiding precision
  surgery or training.

ultrasound guided needle biopsy
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Applications

• Assembly, maintenance and repair Instructions
  available on-site as superimposed 3D drawings
  (video)

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Applications

• Visualization e.g. architects may visualize how
  a particular structure will change the view of
  the environment. Or they may employ x-ray
  vision to visualize pipes, electric lines or
  structural supports inside walls (video).

• Annotation tag objects or enviroments with
  public or private information. E.g. a context
  sensitive (hand-held) display could provide info
  on library books as the user walks around a
  library.

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NaviCam Rekimoto, UIST94
context-sensitive information assistant
object ID
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Applications

• Robot path planning due to long communication
  delays with a real robot, controlling the virtual
  version may be preferable
• Military aircraft superimpose vector graphics
  onto the pilots view of the world

• Entertainment e.g. virtual sets merging real
  actors with virtual backgrounds

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Applications

• Wearable computing context-sensitive mobile

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http//www.microopticalcorp.com/
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Types

• Optical see-through HMD
• Video see-through HMD
• Monitor based AR

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Optical See-Through HMD
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Video See-Through HMD
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Monitor based AR
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Issues in AR
Whats wrong with this picture?
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Issues in AR

• WIMP interface is fundamentally wrong for AR
• Users are very sensitive to visual offsets (lt1
  min of arc) - HMD trackers and displays cannot
  provide this level of accuracy the registration
  problem (not so much a problem in VEs). Note
  that some applications will demand high accuracy!
• Static errors optical distortion errors in
  tracking misalignments
• Dynamic errors end-to-end system latency (pot.
  solutions lag reduction temporal stream
  matching (only w. video based systems) location
  prediction)
• AR is in its infancy No turnkey, off-the-shelf
  AR systems available much research still needed
  on perceptual, cognitive and social issues