Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!gem.mps.ohio-state.edu!tut.cis.ohio-state.edu!bloom-beacon!primerd!hollin!ds
From: ds@hollin.prime.com
Newsgroups: comp.cog-eng
Subject: Re: one-finger keyboard
Message-ID: <24700003@hollin>
Date: 16 Oct 89 20:43:00 GMT
References: <221013@<1989Oct6>
Lines: 40
Nf-ID: #R:<1989Oct6:-22101300:hollin:24700003:000:2185
Nf-From: hollin.prime.com!ds    Oct 16 16:43:00 1989


Sorry I'm late in responding to this...  I think the best keyboard design for
using one finger is the "wipe" design that appeared in a magazine some years
ago (sorry, can't remember where, maybe Byte or Radio Electronics).

The idea was that the most common English digraphs and trigraphs were located
in adjacent left-to-right positions.  You could type some common words such as
"the" and "you" in a single wipe across three keys.

I think this would work best when the keys do not move (that is, they sense
when a finger makes contact with them, such as by sensing the impedance
difference in a tuned circuit due to the capacitive effect of the finger).

Having a groove or channel or at least flatness between keys would make wiping
easier, but would make accurate positioning for single-character pressing
harder (as compared with providing a concave indentation in the solid keyboard
the size of each key).

Considering different keyboard layouts of course assumes that users are
willing to spend the considerable time and effort required to learn them.  I
suspect that, in general, they are not.

The above applies mostly to non-handicapped users.  If I were handicapped to
the extent that I could use only one finger, I would want a keyboard whose
keys I could periodically remap such that most keys corresponded to character
strings I frequently used, or even to whole phrases, sentences, or other
meaningful constructs (I might press one key to specify a general topic and
another one or two keys to narrow it down).  Such a keyboard would have
user-programmable modes, one for common strings, one for all the ASCII
characters, and other modes as I thought them up.  I would display the strings
currently mapped to each key in a window on the display screen, and I would
watch the screen rather than the keys as I typed (even better would be a
display screen/keyboard combination).  The design would have to reflect the
different contexts in which a keyboard is used, such as to communicate
directly with people (assuming I cannot speak, for example), to program a
computer, to write a letter, etc.

David Spector
Prime Computer, Inc.
ds@primerd.prime.com (until the layoff)