Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!zephyr.ens.tek.com!uw-beaver!milton!hopper@ntmtv.UUCP
From: hopper@ntmtv.UUCP (Ian Hopper)
Newsgroups: sci.virtual-worlds
Subject: Re: motion sickness problem
Message-ID: <866@ntmtv.UUCP>
Date: 4 Mar 90 03:55:11 GMT
References: <16311@well.sf.ca.us>
Sender: hlab@milton.acs.washington.edu
Organization: Northern Telecom, Mtn. View, CA
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Approved: hitl@hardy.u.washington.edu

>From article <16311@well.sf.ca.us>, by nelson_p@apollo.com:
> 
> 
>   At SIGGRAPH '89 in Boston there was a panel discussion on
>   Virtual Environments in which Scott Fisher from NASA/Ames 
>   indicated that one of the major problems that they've been
>   having with these experiments is motion sickness.   Virtual
>   reality devices like videophones produce input to the human
>   sensory system which is at odds with what the vestibular 
>   system indicates.    The more realistic the simulation the
>   worse the motion sickness becomes.   The problem apparently 
>   affects a significant percentage of people using such systems.
>   If this is so then it could greatly limit the applicablity
>   of virtual reality systems.   Does anyone know what the status
>   is of research to try to control this problem?
> 
>                                                ---Peter
I'll attempt to speak for Scott Fisher, who apparently does not post
on the net very often.

As has been said, the sickness is the result of a mis-match between
what the eyes are seeing versus what the balance organs of the inner-ear
are "feeling".

The usual problem si for those folks who are using the "ISO Track" 6-degree
of freedom position sensing system.  The positions it reports to your
favourite computer/graphics system are often a solid fraction of a second
behind the current position.

The effect on the person wearing the "eye-phones" is that the "world" takes
the same fraction of a second to "catch up" with your head motion.  Rather
like being REALLY drunk and is equally sickening.

The (lack of) performance of your computer/graphics engine can add to this 
effect. (That is where the $100K graphics system *might not* be fast enough.)

An interesting question is: How accurate do you have be in order to avoid the
effect?

An unsolvable version of the problem arises in flight-simulation systems,
the pilot is in the middle of a virtual strong turn, but there is none of
the appropriate sensation because the guy is not really sitting in an airplane.
Clearly the sensation of up-side down flight is difficult to simulate without
either turning the simulation platform upside down, or using your ACME anti-
gravity generator.

-- 
Ian Hopper		{amdahl.com,ames.arpa,hplabs}!ntmtv!hopper
Northern Telecom Inc.	[Clever comment under construction.]