Virtual reality • An immersive multimedia experience • Games • Training in a simulator • Exploration of environments • Remote control/ robotics • Therapy • (many other potential applications as well)
Virtual Reality • Three fundamental ideas (da Costa et al.) • Immersion • Interaction • Presence
Virtual reality • Immersive computer graphics, contingent on user’s behavior • Head-mounted display (often) • Synchronized sounds (usually) • Synchronized proprioceptive feedback (sometimes: motion, tactile output) • Moving air; smells (rarely)
Readings • Virtual city for cognitive rehabilitation • Overcoming phobias by virtual exposure • Virtual reality treatment in acrophobia: A comparison with exposure in vivo • Exploratory design and evaluation of a user interface for virtual reality exposure therapy
VR Education & Rehabilitation By Inman, Loge, & Leavens • Goal: to train disabled children to use motorized wheelchairs
Problems • Achieving realistic crashes • Achieving realistic stops and starts • Limitations in resolution - tradeoff between speed and realism • Motivation problems (learned helplessness)
3 training scenarios: • Simple world with no obstacles • Interesting, grassy place with objects and places to get stuck in • Traffic intersection
Other applications of VR • Cognitive rehabilitation • http://www.icdvrat.reading.ac.uk/2000/papers/2000_38.pdf • Overcoming phobias • http://www.do2learn.com/aboutus/research/phobia.htm • Training (pilots, soldiers, astronauts, first responders, etc.)
Human factors issues: What can go wrong with virtual reality?
Simulator Sickness (Schroder) A feeling of sickness resulting from exposure to a computer-generated space. • the part inherent to the stimulus itself, present even if the simulation were a perfect representation of the real world • the part that results from an imperfect simulation, for instance due to lag, poor inter-ocular adjust, poor resolution, etc
Simulator Sickness Types of symptom: • Nausea • Oculomotor • Disorientation
Fatigue Headache Eyestrain Difficulty focusing Increased salivation Difficulty concentrating Fullness of head Blurred vision Dizziness Vertigo Stomach awarenesss Burping Simulator Sickness Questionnairehttp://www.hitl.washington.edu/publications/r-9811/node135.html Rate for severity: none, slight, moderate, severe
Relative severity of symptoms:Disorientation, Nausea, Oculomotor Virtual environments: D>N>O Space sickness: O>D>N Simulator sickness: O>N>D Sea/airsickness: N>D>O Virtual environment (e.g., head-mounted display) scores tend to be higher and reported by more users.
Adapting to Virtual Environments • People do adapt (become less sick) • But they must re-adapt upon returning to the “real world” • To what extent do aftereffects go away? • Postural stability, hand-eye coordination, visual functioning
User initiated control • Active motion is better than being a passive observer in VE • But moving about with no constraints can be overwhelming also • Coupled control minimizes cybersickness - task constrains motion • Allow users several sessions to adjust
Health and safety issues (Viire) • Visual changes are temporary in adults • Alignment is critical for stereo images • Focus is constant in stereoscopic HMD, whereas it shifts in a real environment • How should an object look when you get close to it?
Other dangers • Loud sounds (well understood) • Injury due to not seeing real environment • Flicker vertigo or migraine • Psychological: If VR can have positive effects (helping with phobias), it can probably desensitize people to other things also (such as violence).
Conclusions: Virtual Realty • Useful for training in dangerous environments or for learning in infeasible environments • Can be used to systematically desensitize phobias • Can be used in rehabilitation • (but beware of cybersickness!) • adjust gradually w/ breaks • warn of possible effects • give user control of motion • constrain environment
The Cutting Edge • Virtual Human Interaction Lab • Avatar Identity • Transformed Social Interaction • Haptic Communication • Massively Multiplayer Online Gaming • Eyewitness Testimony & Police Lineups • VirtuSphere • http://www.sciencedaily.com/videos/2006/0409-the_new_virtual_reality.htm