[sci.virtual-worlds] Cheap head-mounted display

cdshaw@cs.ualberta.ca (Chris Shaw) (05/09/91)

In article <LongerAndLongerAndLongerAndLonger> Greg ? writes:
>Second, does anyone have any ideas about a cheap version of eyephones?  

There's a device called the "Private Eye", which is a head-mounted display
device that uses a spinning mirror to scan a column of 280 LEDs across
your face. Resolution = 720x280. It's pretty cheap. It's made by
Reflection Technology, Inc. Sorry no address. Anybody got an address for these
people?

>It seems to me that a powerglove could be used for the position sensor 
>(just aim it backwards, and put the receivers behind you) and still 
>let you use a power glove for a glove.  

The noisiness of the data given by the ultrasound sensors will drive you wild.
You'll probably have to use a Polhemus Isotrak for head tracking.

>Then, 2 EGA/VGA cards...

The rest of the post is on the right track. See Randy Pausch's paper in CHI 91,
"Virtual Reality on Five Dollars a Day". The most expensive part of his system
is the Isotrak at $3000. His total system cost is $10,000, and he's doing
some of the best work in this area.

>     -Greg
-- 
Chris Shaw     University of Alberta
cdshaw@cs.UAlberta.ca           Now with new, minty Internet flavour!
CatchPhrase: Bogus as HELL !

wave@media-lab.media.mit.edu.MEDIA.MIT.EDU (Michael B. Johnson) (05/11/91)

In article <1991May10.205155.27367@milton.u.washington.edu> you write:
>>
>>
>>
>>In article <LongerAndLongerAndLongerAndLonger> Greg ? writes:
>>>Second, does anyone have any ideas about a cheap version of eyephones?
>>
>>There's a device called the "Private Eye", which is a head-mounted display
>>device that uses a spinning mirror to scan a column of 280 LEDs across
>>your face. Resolution = 720x280. It's pretty cheap. It's made by
>>Reflection Technology, Inc. Sorry no address. Anybody got an address for these

>>people?
>>

Reflection Technology
240 Bear Hill Road
Waltham, MA 02154
617-890-5905
617-890-5918 FAX

NOTE: this is their new address - I just typed it in from a FAX I got from
a friend a few weeks ago, so I'm sure it's current.

Also, I believe a developer's kit for a Private Eye can be ordered
from PC Connection.  With the PC CGA emulation card, I believe the kit is
~$500.  Just the Private Eye is ~$400.  Call yourself for the real numbers.

-- 

-->  Michael B. Johnson
-->  MIT Media Lab      --  Computer Graphics & Animation Group
-->  (617) 253-0663     --  wave@media-lab.media.mit.edu

fenwick@clipper.ingr.com (Stephen Fenwick) (05/14/91)

In article <1991May10.205155.27367@milton.u.washington.edu> cdshaw@cs.
ualberta.ca (Chris Shaw) writes:

>In article <LongerAndLongerAndLongerAndLonger> Greg ? writes:
>>It seems to me that a powerglove could be used for the position sensor 
>>(just aim it backwards, and put the receivers behind you) and still 
>>let you use a power glove for a glove.  
>
>The noisiness of the data given by the ultrasound sensors will drive you wild.
>You'll probably have to use a Polhemus Isotrak for head tracking.

Your tarring the whole technology with a too-broad brush.  Ultrasonics
can be used for reliable 2-d and 3-d positioning; I've done it.

The project was a derivation of a head-mouse for the Mac (forgot the name)
that used three receivers on a headband (one on top, one at each ear, all face
forward) and a single transmitter in a base unit placed on top of the Mac.
I'm not sure how much I can say about the techniques used (don't recall
what non-disclosures were signed at the time), but it was quite possible
to get reasonable 3-d positioning (one axis direct, two by translating
rotations to translations) based on a single 68HC11, some cheap glue
logic, and simple software.  Very little filtering (s/w or h/w) was required.

Send me e-mail for more details.

Steve Fenwick
-- 
Do you seriously think my company would let me speak for it?
E-Mail routes: { uunet!ingr! } clipper!fenwick
USPS: Intergraph APD, 2400 Geng Road, Palo Alto, California  94303
AT&Tnet: (415) 852-2325

cdshaw@cs.ualberta.ca (Chris Shaw) (05/15/91)

Steve Fenwick :

>In article cdshaw@cs.ualberta.ca (Chris Shaw) writes:
>>The noisiness of the data given by the ultrasound sensors will drive you 
>>wild.
>>You'll probably have to use a Polhemus Isotrak for head tracking.
>
>You're tarring the whole technology with a too-broad brush.  Ultrasonics
>can be used for reliable 2-d and 3-d positioning; I've done it.
>Steve Fenwick

Perhaps I am, perhaps not.

The original post in this thread suggested that the Power Glove ultrasonic
trackers be used for head tracking. This means that you need to track
position and orientation, at all attitudes (no dead spots). For head tracking,
the data should also be low noise, else the jitter will "drive you nuts".
Ultrasonics are probably ideal for position-only tracking, but currently the
powerglove will give only roll-of-forearm data, and will only work when 
your arm is facing the sensor array. Of course, you COULD use this to detect
head-turn +/- 90 degrees, but that's all. No looking up or down with this 
setup. 

Ultrasound is certainly worth looking into, though, because it's got a 
big price advantage.
-- 
Chris Shaw     University of Alberta
cdshaw@cs.UAlberta.ca           Now with new, minty Internet flavour!
CatchPhrase: Bogus as HELL !

fenwick@clipper.ingr.com (Steve Fenwick) (05/16/91)

In article <1991May16.055148.2358@milton.u.washington.edu> cdshaw@cs.ualberta.ca
 (Chris Shaw) writes:

|> Steve Fenwick :
|> >In article cdshaw@cs.ualberta.ca (Chris Shaw) writes:
|> >>The noisiness of the data given by the ultrasound sensors will drive you 
|> >>wild.
|> >>You'll probably have to use a Polhemus Isotrak for head tracking.
|> >
|> >You're tarring the whole technology with a too-broad brush.  Ultrasonics
|> >can be used for reliable 2-d and 3-d positioning; I've done it.
|> >Steve Fenwick
|> 
|> Perhaps I am, perhaps not.
|> 
|> The original post in this thread suggested that the Power Glove ultrasonic
|> trackers be used for head tracking. This means that you need to track
|> position and orientation, at all attitudes (no dead spots). For head tracking
,
|> the data should also be low noise, else the jitter will "drive you nuts".
|> Ultrasonics are probably ideal for position-only tracking, but currently the
|> powerglove will give only roll-of-forearm data, and will only work when 
|> your arm is facing the sensor array. Of course, you COULD use this to detect
|> head-turn +/- 90 degrees, but that's all. No looking up or down with this 
|> setup. 
|> 
|> Ultrasound is certainly worth looking into, though, because it's got a 
|> big price advantage.

Serves me right for jumping into the middle of a thread!  I assume the
powerglove you're talking about is the Nintendo glove.  I can't agree about
the roll-of-forearm only, since it seems to pick up pitch, yaw, and one axis of
translation (at least when my cousin/video-game addict uses it!)
This holds with what I found out in my project, which seems to have been
exactly the same as the powerglove, but wearing the three sensors instead
of the transmitter.

You're right, in that the three receiver/one transmitter scheme won't
let you pick up absolute 3-d position and attitude;  it will give
you three easy-to-use degrees of freedom (pitch, yaw, one translation),
and can thus be used a a 3-d control.

I was working on this in 1987, well before the glove came out,
and the project was based on a 1986 Mac mouse replacement (head-mounted;
lots of apps for handicapped.)  Contact Dr. Mark Friedman at Carnegie-Mellon
for more details.

P.S.  I tried replying to your mail, Chris, but it bounced locally.

fenwick@clipper.ingr.com        +-----------------------------------------+
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-- 
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(415) 852-2325/494-8800