Transcript HF 2 - Augmented Reality

Human Factors 2: Augmented Reality
 Characteristics of AR
systems
 Applications
 Types of AR
 Issues in AR
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 VE’s, AR supplements reality rather than
replacing it
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.
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 user’s senses otherwise.
Applications
 Medical: project non-invasive imaging scans (MRI,
CT, ultrasound) onto the patient’s body - “x-ray vision”.
Particularly useful for minimally invasive surgery. Also
for guiding precision surgery or training.
ultrasound guided needle biopsy
Applications
 Assembly, maintenance and repair: Instructions
available on-site as superimposed 3D drawings
(video)
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 (handheld) display could
provide info on library
books as the user walks
around a library.
NaviCam [Rekimoto, UIST’94]
context-sensitive information assistant
object ID
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
pilot’s view of the world
 Entertainment: e.g.
virtual sets merging
real actors with
virtual backgrounds
Applications
 Wearable computing: context-sensitive & mobile
http://www.microopticalcorp.com/
Types
 Optical see-through HMD
 Video see-through HMD
 Monitor based AR
Optical See-Through HMD
Video See-Through HMD
Monitor based AR
Issues in AR
What’s wrong with this picture?
Issues in AR
 WIMP interface is fundamentally wrong for AR
 Users are very sensitive to visual offsets (<1 min of arc) HMD trackers and displays cannot provide this level of
accuracy: the registration problem (not so much a
problem in VE’s). 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