Case Study

Low cost VR system for Media Study, University at Buffalo

Projectors and filters



Specifics of UB system and decisions
  • Penguin PC running linux for the graphics 
    • waited for linux drivers for the dual head cards
    • started with a matrox 450, now have GeForce 4
  • Projectors
    • Sharp projectors with lens shift - this feature makes it easier to align the 2 channels of video
    • We got the last 2 on the market
  • Circular polarizing filters for the projectors and for the glasses
    • circular polarization means that polarization is not lost if the user tilts their head
Screen, tracker antenna
  • Screen
    • 7' x 5' (2.1 x 1.5 metres) Disney black screen with aluminum frame
    • The sharp projectors had a long throw distance and therefore the space where the system was installed was a limiting factor in determining the possible size of the screen
    • We decided against bouncing the image of a mirror - largely because of logistics, and there can also be some tricky problems with the passive stereo which Dave will touch on later
    • Fears that the aluminum screen would create noise in the tracker proved unfounded
wanda, tracking sensors
  • Ascension SpacePad Tracker 
    • purchased because we were familiar with it and found it reliable and its relatively inexpensive.
    • we built our own antenna - from a diagram supplied by Greg Dawe at EVL
    • we bought 3 tracking sensors, 1 for the head, 1 for each hand
  • Hand-me-down tracking PC 
    • running windows 98
    • isa-slot for space-pad card - the card is extremely large
  • Murray Consulting Wanda 
    • purchased because we were familiar with it, and knew it would work
    • one tracking sensor is installed in the wanda
speaker, black walls
  • Sound
    • mackie mixer
    • four speakers
    • linux PC running Pd for spatialization and sound design
    • black sound proofing and painted black walls for elegance
crayoland on sheet
  • Current Software setup
    • CAVElib
    • OpenGL
    • Performer
    • because of our own legacy software and preferences we wanted to be able to use Performer, and this was one of the major reasons for opting for the linux OS
    • Pd and Bergen sound software
Use of System >>