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Introduction to Introduction to Virtual EnvironmentsVirtual Environments

CIS 4930/6930CIS 4930/6930

Benjamin LokBenjamin Lok

Spring 2009Spring 2009

OutlineOutline

Define Virtual Reality / Virtual Define Virtual Reality / Virtual EnvironmentsEnvironments

Explore the spectrum of VRExplore the spectrum of VR

Components of VRComponents of VR

Applications of VRApplications of VR22

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Virtual Reality DefinitionVirtual Reality Definition

What is virtual reality?What is virtual reality? Virtual – Virtual –

being in essence or effect, but not in factbeing in essence or effect, but not in factExample VRAMExample VRAM

Reality –Reality –the state or quality of being real. Something that the state or quality of being real. Something that exists independently of ideas concerning it. exists independently of ideas concerning it. Something that constitutes a real or actual thing as Something that constitutes a real or actual thing as distinguished from something that is merely distinguished from something that is merely apparent.”apparent.”

What was the first VR?What was the first VR?

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What was the first VR?What was the first VR?

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Define VRDefine VR

Take a few minutes and write a 1-2 sentence Take a few minutes and write a 1-2 sentence definition.definition. What are the important components?What are the important components?

Burdea (Rutgers):Burdea (Rutgers):Virtual reality is a high-end user-computer Virtual reality is a high-end user-computer interface that involves real-time simulation and interface that involves real-time simulation and interactions through multiple sensorial channels. interactions through multiple sensorial channels. These sensorial modalities are visual, auditory, These sensorial modalities are visual, auditory, tactile, smell, and taste.tactile, smell, and taste.

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Burdea’s 3 I’s of VRBurdea’s 3 I’s of VR

Interactivity – user impacts worldInteractivity – user impacts world DefineDefine ChannelsChannels

Immersion – believing you are thereImmersion – believing you are there DefineDefine What contributes to it?What contributes to it?

Imagination – user ‘buying’ into the experienceImagination – user ‘buying’ into the experience Examples Examples Why is this necessary?Why is this necessary?

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Our definition (from Brooks’ What’s Our definition (from Brooks’ What’s Real About Virtual Reality)Real About Virtual Reality)

Virtual Reality Experience – the user is Virtual Reality Experience – the user is effectively immersed in a responsive virtual effectively immersed in a responsive virtual world.world.

Implies -> user dynamic control of viewpointImplies -> user dynamic control of viewpoint

Control becomes an important element of VR Control becomes an important element of VR systems.systems. Differentiates VR from books and movies (or watching Differentiates VR from books and movies (or watching

movies in HMD)movies in HMD) Why is control more important?Why is control more important?

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Ivan Sutherland’s Ivan Sutherland’s The Ultimate DisplayThe Ultimate Display

““Don’t think of that thing as a Don’t think of that thing as a screen, think of it as a screen, think of it as a window, a window through window, a window through which one looks into a virtual which one looks into a virtual world. The challenge to world. The challenge to computer graphics is to make computer graphics is to make that virtual world look real, that virtual world look real, sound real, move and sound real, move and respond to interaction in real respond to interaction in real time, and even feel real.”time, and even feel real.”

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Key Elements of Virtual Reality Key Elements of Virtual Reality ExperienceExperience

Virtual World - content of a given mediumVirtual World - content of a given medium

Immersion – sensation of being in an Immersion – sensation of being in an environmentenvironment

mental immersion – suspension of disbeliefmental immersion – suspension of disbelief physical immersion – bodily entering the physical immersion – bodily entering the

mediummedium Related to Related to presencepresence – (mentally immersed) – (mentally immersed)

the participant’s sensation of being in the the participant’s sensation of being in the virtual environment (Slater)virtual environment (Slater)

Walking Experiment atUNC – Chapel Hill

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Key Elements of Virtual Reality Key Elements of Virtual Reality ExperienceExperience

Sensory Feedback – information about the Sensory Feedback – information about the virtual world is presented to the participant’s virtual world is presented to the participant’s sensessenses

Visual (most common)Visual (most common) AudioAudio TouchTouch

Interactivity – the virtual world responds to the Interactivity – the virtual world responds to the user’s actions.user’s actions.

Computer makes this possibleComputer makes this possible Real-timeReal-time

Walking Experiment atUNC – Chapel Hill

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Why VR?Why VR?

When should we When should we apply VR?apply VR?

OutlineOutline

Define Virtual Reality/Virtual EnvironmentsDefine Virtual Reality/Virtual Environments

Explore the spectrum of VRExplore the spectrum of VR

Components of VRComponents of VR

Applications of VRApplications of VR

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Virtual EnvironmentsVirtual Environments

Augmented Reality (Mixed Reality)Augmented Reality (Mixed Reality)

TelepresenceTelepresence

Artificial RealityArtificial Reality

Virtual RealityVirtual Reality

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Augmented RealityAugmented Reality

A combination of a A combination of a real scene viewed by real scene viewed by a user and a virtual a user and a virtual scene generated by a scene generated by a computer that computer that augments the scene augments the scene with additional with additional information.information.

Ultrasound Visualization Research atUNC – Chapel Hill

All Virtual Objects All Real Objects

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TelepresenceTelepresence

The use of various technologies to The use of various technologies to produce the effect of placing the user in produce the effect of placing the user in another location.another location.

All Virtual Objects All Real Objects

Mixed RealityMixed Reality

Merging of the real Merging of the real and virtual worldsand virtual worlds

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Virtual RealityVirtual Reality

Ideal for VR is that Ideal for VR is that everything you everything you experience is experience is computer-generated.computer-generated.

All Virtual Objects All Real Objects

OutlineOutline

Define Virtual Reality/Virtual EnvironmentsDefine Virtual Reality/Virtual Environments

Explore the spectrum of VRExplore the spectrum of VR

Components of VRComponents of VR

Applications of VRApplications of VR

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Components of VRComponents of VR

DisplayDisplay

Tracking SystemTracking System

UserUser

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2020

Immersive TechnologyImmersive TechnologyHead-mounted Head-mounted DisplayDisplay Optical SystemOptical System Image Source (CRT or Image Source (CRT or

LCD)LCD) Mounting ApparatusMounting Apparatus EarphonesEarphones Position TrackerPosition Tracker

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Immersive TechnologyImmersive Technology

Multi-screen Projection of Multi-screen Projection of stereoscopic images stereoscopic images (CAVE)(CAVE)

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Immersive TechnologyImmersive Technology

Single large Single large stereoscopic displaystereoscopic display Projection-basedProjection-based Head-trackedHead-tracked Possible tracking of Possible tracking of

hands and arms.hands and arms. Brings virtual objects Brings virtual objects

into the physical worldinto the physical world

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User’s perspectiveUser’s perspective

SettingSetting

Objects in worldObjects in world

Other participantsOther participants

Active/PassiveActive/Passive Factory SimulationFactory Simulation Architectural Architectural

WalkthroughWalkthrough

OutlineOutline

Define Virtual Reality/Virtual EnvironmentsDefine Virtual Reality/Virtual Environments

Explore the spectrum of VRExplore the spectrum of VR

Components of VRComponents of VR

Applications of VRApplications of VR

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ApplicationsApplications

Most current applications:Most current applications:

Special PurposeSpecial Purpose

Interaction simple and/or infrequentInteraction simple and/or infrequent

Sidestep limitations of graphics and Sidestep limitations of graphics and hapticshaptics

A few expensive systems are sold to a few A few expensive systems are sold to a few rich peoplerich people

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EntertainmentEntertainment

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Design VisualizationDesign Visualization

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Training (NASA)Training (NASA)

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Clinical Virtual RealityClinical Virtual Reality

The direct use of VR as a tool in the treatment or The direct use of VR as a tool in the treatment or assessment of psychological and physical assessment of psychological and physical

disorders.disorders.

Hunter HoffmanHITLab – University of Washington

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