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?