john@nmt.edu (John Shipman) (09/01/90)
A number of people have asked me about the advantages of the
Dvorak keyboard, so here are some excerpts from the article in
which I first found out about the Dvorak keyboard: ``The Dvorak
Simplified Keyboard: Forty Years of Frustration,'' by Robert
Parkinson, from the November 1972 issue of a magazine called
_Computers_and_Automation_.
---begin quoted excerpt---
BACKGROUND ON KEYBOARD DESIGN
[The QWERTY keyboard] was designed experimentally by
Christopher Sholes, the inventor of the typewriter, to SLOW THE
TYPIST DOWN. ...The keys on the early machines...pivoted up to
strike the platen (roller) from underneath.... Since the keys
had no springs on them, they fall back into place by gravity.
This meant their action was very sluggish, and if two keys that
were close together in one quadrant of this ``basket'' were
struck rapidly, one after another, they would jam. To overcome
this problem, Sholes moved the keys around experimentally until
the machine seemed to operate with a minimum of jamming. What
he actually did was to make many commonly-used letter sequences
awkward and slow to execute. Thus, by ``anti-engineering'' his
typewriter from a human factors point of view, he was able to
slow it down so it would function to his satisfaction. Now,
when we have [keyboards] that are mechanically quite
responsive, we are still bound by the old keyboard found on
those first (1873) machines. What an irony!
DEFECTS
Upon analysis, Dr. Dvorak found that the [QWERTY] keyboard had
several defects....
Hand overload: This occurs when more than one character has to
be typed by the fingers of the same hand.... The fastest and
easiest strokes occur for characters on the home row and on
opposite hands.
Unbalanced finger loads: [QWERTY] overworks certain fingers and
underworks others, all out of proportion to their capabilities
(taking into account strength and dexterity of each finger.)
Excess finger movement: Because of the way the characters are
spread out over the whole keyboard, fingers must reach from and
jump over the home row far too often....on the standard
keyboard the ``home row'' is not really a home row at all since
only 32% of all typing is done there.
Awkward strokes: ...many high frequency letter combinations are
unnecessarily complex and difficult to execute (just try typing
``December'' or ``minimum pumpkin'' without looking!).
RESEARCH
After several years of intensive research, during which
hundreds of keyboard arrangements were studied and rejected,
Dr. Dvorak received a patent for his Dvorak Simplified Keyboard
in 1932. The DSK solves the basic problems inherent in the
[QWERTY] keyboard.
Better hand alternation: The hand overload problem is solved by
maximizing alternate hand stroking. This is particularly
important in maintaining rhythm. As much as possible,
successive strokes should fall on alternate hands. This allows
what is called ``play for position.'' That is, while a finger
on one hand is in the process of stroking a key, another finger
on the opposite hand can be getting into position to stroke the
next key---and so on.... Dr. Dvorak solved this problem by
putting the vowels (which comprise 40% of all typing) on the
left hand side of the keyboard, and the major consonants which
go along with those vowels on the right hand side. This
guarantees good hand alternation since most syllables are made
up of vowel-consonant-vowel letter sequences.
/ , . P Y F G C R L Top row
A O E U I D H T N S Home row
^^^^^^^^^^^^^ ^^^^^^^^^^^^^ (home finger positions)
; Q J K X B M W V Z Bottom row
Better finger loads: ...the DSK arrangement precisely divides
the finger loads according to relative finger capabilities.
More work (70%) done on the home row: [diagram showing that on
the DSK, 22% of typing is done on the top row, 70% on the home
row, and 8% on the bottom row; for QWERTY, those numbers are
52%, 32%, and 18%.]
Awkward strokes minimized: The rest of the characters,
comprising the typing that has to be done off the home row, are
placed on the DSK in positions on the remaining rows according
to how hard it is to strike the keys in those rows. This is
done such that the total number of awkwards strokes is
minimized (the ``awkwardness'' of various types of strokes was
determined using high-speed time-and-motion movies)....since
awkward strokes are sometimes slower by a factor of three to
one, and since the DSK reduces the number of these strokes by a
factor of ten to one, one can see how it is possible to achieve
a faster typing rate on this keyboard (and why Dr. Dvorak's
students hold 12 out of 15 unbeaten world typing records.)
--- end quoted excerpt ---
The rest of this article describes the history of the keyboard,
or, as the next section head says, ``If it's so good, why is
nobody using it?''
However, this article is already pretty long. If enough people
request it, I will post that story here. For now, though,
here's a relevant quote from the end of the article:
...Dr. Frank Gilbreth (under whose direction Dr. Dvorak began
the research that led to developing the DSK), the father of
time and motion study, said, ``It is cheaper and more
productive to design machines to fit men rather than try and
force men to fit machines.''
--
John Shipman/Zoological Data Processing/Socorro, NM/john@jupiter.nmt.edu
``Let's go outside and commiserate with nature.'' --Dave Farber