From: dstamp@watserv1.waterloo.edu (Dave Stampe-Psy+Eng)
Subject: Re: 6-D Gyroscopic mouse announced
Date: Sun, 8 Dec 1991 02:44:28 GMT
Message-ID: <1991Dec8.024428.7243@watserv1.waterloo.edu>
Organization: University of Waterloo


dither@vms.macc.wisc.edu (Dennis Adams) writes:

>>Three axes of movement, three axes of rotation? Does this mouse do
>>this?
>
>No.  According to the literature I have from Gyration, it provides three
>axes (rotation).  It is up to the application to decide to use this for
>rotation or (rather non-intuitive) translation.  There are switches that
>could be used to toggle or set modes (Five total, one of which senses
>when it is sitting on your desk).  It is not clear how it acts as a 2D
>mouse when it is on the desk.  Also, it is limited in two or three of the
>axes -- if you move past about 80 degrees in pitch (and perhaps roll) the
>gyros gimbal-lock and need to be reset (15 seconds).  Yaw does not have
>this problem.

That sounds pretty much as I imagined it.  This is still right in the
needed range for head-angle tracking.  You can use other techniques for
position, since resolution and noise are less important.

Did the literature specify price, resolution, noise, response speed, etc?
Is there a maximum rotation rate that it can track?  Another important
parameter is drift.  All gyros drift by some angle: question is if it's
1 degree/sec (typical of RC helicopter gyros) or 1 degree/min (VR quality)
or 1 degree/week (navigational quality).

--------------------------------------------------------------------------
| My life is Hardware,                    |                              | 
| my destiny is Software,                 |         Dave Stampe          |
| my CPU is Wetware...                    |                              | 
| Anybody got a SDB I can borrow?         | dstamp@watserv1.uwaterloo.ca |
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