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t directly with the objects
VR to walk around, stop, touch, manipulate and interact
VR can help to improve the visual appearance; texture mapping, surface properties. lighting
VR to define kinematic behaviour of objects to demonstrate operation of a product.
How to Get Started in VR
2. WHAT IS VRContrasting VR against CAD
CAD: for entry of data for model creation. Then can rotate and view
VR: to display models, places users inside the model - to interact directly with the objects
VR to walk around, stop, touch, manipulate and interact
VR can help to improve the visual appearance; texture mapping, surface properties. lighting
VR to define kinematic behaviour of objects to demonstrate operation of a product.
The main components of a VR system
Virtual Environment Generator
A high performance computer that maintains the database and executes the VR software.
Database: Maintains shape representation (from CAD*) of the virtual objects
Maintains their visual & behaviour characteristics
(*eg. AutoCAD, Bentley, Unigraphics, Catia) or visual simulation modelling packages (eg. MultiGen, Designer’s Workbench)
Visual Interface (Seeing)
-Visual display interface: to render images in real-time
-For smooth simulations 30 frames/sec
-This large computational load is handled by the graphics hardware.
Auditory Interface (Hearing)
-The role of the auditory interface is to generate realistic auditory cues
-Takes either real or synthetic audio signals, spatialised in a 3600 sphere.
-Can be ‘space stabilised’ or moving around in space.
eg a ticking clock in a precise position appearing stationary
How to Get Started in VR - 2. WHAT IS VRHaptic Interface (Feeling) = tactile feedback + force feedback.
Tactile feedback when an object is lightly touched or stroked.
-to feel surface properties (roughness, smoothness, flatness and temperature)
Force feedback to stop user’s body parts penetrating into virtual rigid bodies.
Tracking Interface (Movement)
-SW&HW to track the positin of head and hand
-To sense where you are looking and your hand position.
See workbook for case studies
(eg. St Gregory’s School, Docklands Light Railway and Remodelling of Proof House
Junction in Birmingham.)
How to Get Started in VR
2. WHAT IS VRA complete VR system:
To provide links (eg. visual interface to generate images)
a tracking interface to follow the body movements of user
an auditory interface to generate realistic audio cues
a haptic interface to provide touch and force feedback to the user
VR system configurations
Non-immersive (Desk-top) VR
-Low cost option
-Display via conventional desk-based high-resolution monitor.
-A variation is ‘panoramic VR’: user fixed in one position and the surrounding world is mapped
to the inside of the sphere or drum.
-Provides 360° view of the environment. But limited zoom and vertical rotation functions.
Semi-immersive VR
-Projection-based VR systems. –
Eg Reality Centres and Immersive Workbenches
-Provide a wider field of view thus greater sense of presence .
Fully immersive VR
-A sense of full immersion.
-A visual image wherever the user is looking - 360° field of regard
-Use a head-coupled display: head-mounted or move with the head.
-Typical input devices track the natural body function, eg data glove
How to Get Started in VR
3. describing the different parts t