Interactive Systems Technical Design
Seminar work: Virtual Reality
Teemu LaukkarinenJuha Mustonen
Pekka Mäki-Asiala
Introduction - Definitions Virtual Reality -> Virtual Worlds -> Virtual Environment
Artificially created believable impression of objects, environment or space that doesn’t exist in reality.
To measure the degree of virtuality we can use three gauges : autonomy - modelling objects and processes interaction - possibility to interact with the environment presence - deceiving all senses to believe it is real
Immersion : Loss of consciousness of the outside world; feeling of being
surrounded by a completely other reality. Immersion is psychological - relates to individuals.
Motivation - Where & WhyEntertainment
gaming industry interactive virtual worlds theme parks
Visualization architecture, chemistry, CAD arts and tourism acoustics
Simulation & training military, civillian (police, firefighters), medicine, handicap aid robots (remote control)
Implementation - needs/ways?
Implementing a virtual environment starts by defining needs.What is the level of immersion?
Visual Audible Smell and taste - No technologies at the moment. Tactile feedback - force feedback Sense of balance - location and position detection
Visual (1/3)Sight is the most important channel of sensory
Our eyes are :accurate - real world details vs. computer generated resolution accommotative - adapts to different distancesadaptive - lighting conditions
Fooling the eyefield of vision - 180o x 120o, must be covered totallymotion detection - perspective and texture changesstereopsis - perseption of depth
Immersive VR displays 1. Head-Mounted Display (HMD) 2. Virtual Model Display (VMD)3. Spatially Immersive Display (SID)
Visual (2/3)
VMD (Virtual Model Display)Example: ImmersaDesk
Huge monitor, stereo vision (shutter glasses)Possibly head tracking
+ Multi-user possibility- low immersion
HMD (Head-Mounted Display)User wears a helmet that projects separate image for both eyes Head orientation tracking important!
+ Relatively cheap - Field of view limited (resolution) - Uncomfortable to wear
Visual (3/3)
2. Curved wall setup1. one curved wall
SID (Spatially Immersive Display)User is surrounded physically by the display
1. CAVE-type setup3-6 ”walls”
2. curved overhead screen3. sphere
AudibleWe hear with our ears and with our body
3D - sound is produced usingmultiple speakers with/or dsp headphones - HMD
Sensing the direction of sound differences between sound pressure delays - between ears shape of our ears
Other factors reflections, absorption - acoustics, dsp visual and audible synchronization doppler - is the object approaching?
Tactile & force feedbackVery primitive ways compared to visual and audible feedbackCutaneous and Vestibular Senses (touch and balance)
Skin, joints, muscles, inner ear, internal organsTactile feedback helps to identify objects and shapesForce feedback is essential part in developing many entertainment and industrial applications
Techniques electrical - vibrating crystals magnetical - changing magnetic fields hydraulics - compressed liquid pneumatics - sense of pressure SMA (Shape Memory Alloy)
Location and position detection
Detecting location, movement and position of : head - adjusting graphics, frames, delays - important hands - data gloves (e.g. virtual surgery) body - virtual suits, exoskeletons (e.g. entertainment)
Location trackers performance can measured
resolution and accuracy, - measured value vs. real value response time - update rates and latencyrepeatability - variations between measurements
1. mechanical - accurate, low latency, restricts movement2. magnetic - accurate, inexpensive, high latency3. optical (camera + tracking point) - accurate, expensive, line of sigth4. acoustic (ultrasound) - inexpensive, line of sight5. inertia and non-inertia - inexpensive,
Applications - CAVE
Vision: Shutter or polarization glasses high resolution CRT projectors
Sense of hearing: Multi channel sound (n x speakers)
Sense of balance: Head location and position detection
Multi-user option: One room many participants
User is inside (immersion in reality): User’s body is visible all the time
CAVE (Cave Automatic Virtual Environment) SIGGRAPH 1992 Cube-shaped room with floor, 3-6 walls, (optional ceiling)
HUTCaveHUT (Helsinki University of Technology) www.tcm.hut.fiTelecommunications and Multimedia Laboratory (TML)
4-sided cave, three walls and a floor, Hardware :
Main computer : Onyx2 InfiniteReality - SGI www.sgi.com Projectors (CRT) : 4 x Electrohome Marquee 8500 LC Crystal Eyes CE2 stereoglasses Audio :
Pentium 4 Linux PC Korg 880 D/A converter 15 Genelec 1029A speakers
Tracking (magnetic tracking) : Ascension Motionstar Input device : Surfman radio mouse
HUTCave - Architecture
The CAVE room layout, side view.
The CAVE room layout.
Things to consider: Ventilation and cooling Power consumption Lighting (relates to contrast) Acoustics (absortion, echo…) Wiring (hidden - maintenance)
CAVE - Strengths Comfortable for user
No need to wear heavy equipment Turning the head is very natural
Very immersive Multi-user option The most popular solution for SID setup these days
Lots of info of ”how and why” Compared to curved wall setups (possible exception - sphere)
Cheap Many applications (universities, industry etc.)
CAVE – Problems Expensive - not for consumer Takes a lot of space - projection distance, wall size, operating
system Permanent installation - moving is not easy
Projector calibration (CRT) and seams of displays Stereo vision with shutter glasses - Synchronization of screens Full 6-sides - Wiring and air conditioning problems Floor
Direct projection: Undesirable shadows Back projection: Material of the floor cannot be the same as
walls
CAVE - Fakespace video
Selected Industrial Players http://www.fakespacesystems.com Development and worldwide deployment and service of
VR technology for business applications since 1988
Products WorkWalls
one or more large projection screens
stereographic images WorkSpaces
CAVE, RAVE II WorkDesks
Desks utilizing stereographic images
WorkTools The CubicMouse, Pinch Gloves etc.
WorkStations Value Added Reseller of HP and SGI
Rave II at Army Research Laboratory in Aberdeen, Maryland
ImmersaDesk R2
Selected Industrial Players WorkTools
Pinch Gloves- Allows users to pinch and grab virtual objects or initiate actions with hand gestures- Detects contact between fingers
The CubicMouse- Allows specification of coordinates in virtual spaces- Three control rods, one for each axis (x,y,z), which can be pushed, pulled and rotated- Also the position and rotation of the controller itself can be taken into accountVIDEO: cubicmouse_medical.mov
Selected Industrial Players Fakespace’s customer examples
Manufacturing US Army TARDEC/National Automotive Center (NAC)
CAVEs for evaluating virtual prototypes and design problems
Oil and gas World Oil / Murphy Oil
Products used to speed and enhance geophysical and geological data interpretation
Education Sun™ Center of Excellence for Visual Genomics
CAVE used to immerse scientists in three-dimensional models of biological systems
Government GM Defense Group
CAVE, WorkWall and ImmersaDesk solutions used in designing and marketing of Light Armored Vehicles (LAV)
Selected Industrial Players http://www.flogiston.com
Flogistation 2001 and 2002
Features a "bubble-hood" display, motion base, hand controller, and a six-channel sound/vibration system
Originally developed as a training system for astronauts and funded by NASA
Has starred in a couple of movies, the most famous appearance in The Lawnmower Man
Flostation 2001
Selected International Research Groups and Projects (EVL)
Electronic Visualization Laboratory (EVL) - University of Illinois,Chicago - http://www.evl.uic.edu
A graduate research laboratory specializing in virtual reality and real-time interactive computer graphics
Research on VR devices (home of the CAVE)
Develops compelling prototypes for improvement and reproduction by the commercial/industrial sector
VR Software (software libraries, toolkits) VR Applications Tele-immersion
“Collaborative virtual reality over networks“ Networking
Tele-immersion as ‘application driver’ for developing high-performance broadband networks
Utilizing VR for artistic purposes
Selected International Research Groups and Projects (Presence-research.org)
Aims to offer up-to-date and relevant information and resources on (tele-)presence
Lists research labs, resources, on-going projects and people concerning VR and telepresence
News Archive Conference dates
Selected International Research Groups and Projects (HIT Lab)
http://www.hitl.washington.edu/ (HIT Lab) Research and development lab in virtual interface
technology Affiliated with the College of Engineering at the University of
Washington in Seattle Project examples
VR pain control VR therapy for spider phobia Motion sickness in VR environments Virtual prototyping of medical robotic interfaces
Selected International Research Groups and Projects (HIT Lab)
VR pain control and therapy for spider phobia Pain requires a conscious attention, being drawn into another
world drain a lot of attentional resources, leaving less attention available to process pain signals
Technology derived from the similar spider phobia project Especially used during woundcare of patients with severe burns
Selected International Research Groups and Projects (HIT Lab)
Since patients with severe burns often report re-living their original burn experience during wound care, SnowWorld was designed to help put out the fire
Patients fly through an icy canyon with a river and frigid waterfall. Patients shoot snowballs at snowmen and igloos (with animated impacts)
Researchers in Finland
Helsinki Arena 2000 Virtual city Elisa Communications & City of Helsinki
Lumeportti Low-cost visualization environment VTT
Helsinki Arena 2000
Project started 1996 – one milestone 2000
Aim to provide services also in the digital media
Leading city of the Europe when it comes to culture and services
Provide wider possibilities in interaction and communications
Helsinki Arena - Services
Panorama tour in centrum 19 different places Links to other worth-to-see - places
Helsinki Arena - Services
Virtual Helsinki - Services
Helsinki Arena - Technologies WWW pages Rich media
JAVA applets – IBM Hot Media Panorama view – 360° Zoom
VRML97 models – TRIDENT Virtual telephone book When traditional methods will fade out ->
3D Directory services competitive solution
Lumeportti
Project in VTT Low cost visualization
environment Can be used for meetings,
training and entertainment
Lumeportti - Technologies
Networked PCs and video projector
All the participants can interact on project data with electronic pens or other interaction devices.
Resources
Virtual Helsinki http://www.virtualhelsinki.net http://www.arenanet.fi http://www.helsinkiarena2000.fi http://www.trident3d.net
Lumeportti http://mango2.vtt.fi:84/tte/projects/vr-cluster/kuvia/
Lumeportti_taitto4.pdf
Future developmentsA few years ago, Virtual Reality was treated as the immediate future by themedia, and then dismissed when technology could not evolve fast enough to be comfortable, affordable, and useful.
3D user interfaces - monitors with shutter glasses Home theaters
Immersive large displays, stereoscopic image, 3D sound Mobile phones, wearable computing -> mixed reality
Thank you
Questions?