From: gauteam@ifi.uio.no (Gaute Amundsen)
Subject: TECH: Sensory Deprivation and VR
Date: Wed, 22 Apr 1992 21:22:24 GMT
Message-ID: <1992Apr22.212224.10717@ifi.uio.no>
Organization: Dept. of Informatics, University of Oslo, Norway



I had this idea some time ago for how to build a VR interface from 
off-the-shelf parts that could give both a full field of view and 
an almost full "bodily presence". 

It involves a bit too much hardware for a computer science student like 
me to test out easily, but I have thought it over for a couple of weeks, 
and I still think it could work. Do you?

The idea is that instead of constructing HMDs and data suits to allow 
the user to "move in data space", one could, by stimulating 
the mind in the right way, use the enormous imaginative and 
adaptive powers of the mind to create an illusion of movement without 
moving the body at all. Not even 5 millimeters... What I am thinking about 
is sensory deprivation (flotation tanks and the like) and the effects 
this can have, such as hallucinations and distortions of your body image.
Combine this with a skin stimulation suit, a state of the art 
simulator system, and some brain machine/hypnosis/subliminal technology, 
and I think you could get some very interesting results.

More specifically I am imagining some kind of "body mold" 
lined with a number of "bladders" or pillows filled with 
body temperature epsom salt solution and dampened by some sponge-like material.
These would each contain a pressure sensor and would be linked 
together by solenoid valves.

The start of a VR session would then go like this...

First you undress and put on the skin stimulation suit 
including gloves, socks, and perhaps a face mask, and make sure the 
stimulation electrodes are in correct alignment.

You plug the suit in and lie down on the "mold", face down, and adjust the 
hand molds and the view port to a comfortable position. 

The solenoids are now closed and the mold feels a bit bumpy, 
but as the mold closes around you they open and as the gentle hum 
and whispers of the brain machine fills your ears and strange floating 
images appear in front of you the mold shapes it self around you and soon 
fades out of existence. Soon after your body image fades too and you 
exist only as a mind in space. As the EEG, pulse, breathing, 
skin resistance, and other monitors built into the system register 
signs of this the solenoids close again, the  scenery changes, and 
you find yourself naked, standing in the gentle surf of some pristine beach 
feeling the water around your legs and the wind in your face. 
The pressure sensors now monitoring every attempted movement.

As you try to move you stagger a bit as your body faintly 
reports that you are not moving at all, but you can see your legs move and 
feel the resistance of the water and hear it splash around your feet.
As the felling of vertigo  disappears and you walk down the beach toward 
the portal standing there the wind gradually takes on another texture, 
more like small feathery points suspended in space like a grid.
then you walk through the portal, and enter your work space.

As you can see something like this would require some quite heavy engineering 
and equipment, especially the skin stimulation and the simulator/VR part, 
but since your head would be stationary the optics could be of a quality 
never possible in an HMD.

Of course all this hinges on the question of weather the brain can learn to 
perceive pressure or attempted movement as the movement that would have 
resulted if it was free to move. And also, to a lesser degree, on the 
question of how the balance organs would react.
 
The last problem there are ways around, like moving the "mold" around, or 
perhaps some kind of electrical or magnetic stimulation. 
Around the first one? Hardly, but at least I think I know a 
quite simple ("non HMD") way to test the principle... 

What you (I) need is a computer with a good flight simulator, a spare key-
board, a good chair and a video projector or a big screen tv. Then, on the 
chair, you build a rig with a helmet or a head-band that will keep your head immobile. Some simple switches on this rig, connected to the keys for up, down, 
left, right, and rear view, detect attempted movement. 

Now place your chair real close to the screen, turn off the lights, 
grab hold of your joystick, and blast away. Then, when the enemy disappears 
off the edge of the screen...

If you have the parts this should be quite close to a one evening project.
With a bit of electronics and some hacking it may even be possible to get 
a continuously variable view. Somebody must have tried this...

Why haven't I done it yet, well.. for one thing I need a flight sim for my Mac.

Gaute Amundsen
gauteam@ifi.uio.no