|-- - -- - - - -ATOMIK and other touch screen keyboard layouts
|The most commonly used graphical keyboards have a QWERTY
layout, invented by Christopher Sholes, Carlos Glidden, and Samuel W.
Soule in 1868 for the purpose of minimizing mechanical jamming. QWERTY was so arranged that many adjacent letter pairs (digraphs) appear on the
opposite sides of the keyboard. Contrary to popular belief, this design
in fact is good for two handed typing, because it also facilitates alternation
of the left and right hand. When used as a stylus keyboard, however, it
means the stylus has to travel back and forth more frequently and over
longer distance than necessary.
Another way to arrange a stylus keyboard is strictly alphabetical along one dimension. Novice users can find keys easily in this layout. The eventual efficiency of such a layout, however, is also poor.
QWERTY as a stylus keyboard
A strictly alphabetical layout for ease of locating keys initially
Third, it maximizes, without sacrificing the first two features, the letter connectivity of the most common words. Many common words or comment fragments of words, such as "the" and "ing" are totally connected.
Stylus tapping points on each key tend to form a 2D Gaussian distribution. Keys in a stylus keyboard hence should be circular. Hexagon keys approximate circles but can still pack without gaps.
When shape writing on a graphical keyboard, the shape of the keys is irrelevant. We therefore used square keys in the revised ATOMIK layout for ShapeWriter. The most frequently used key in stylus tapping, the space key, is no longer as frequently needed and is moved out of the core layout. We also swapped D and K so ED and ING, two common word endings, are more separated.
The shape writing approach we later developed is superior to stylus keyboarding. However if one really wants to stay with the "chicken head motion" of tapping on graphical keyboard, some of the principles in ShapeWriter can be applied to relax the precision requirement of tapping inside every key. Based on a lexicon, an Elastic Stylus Keyboard (ESK) can automatically correct the mis-tapped keys by matching the geometric pattern the user taps against the correct word templates and give the user the word intended.
More technical information, together with literature review on the topics covered in this page, can be found in the following papers:
Research Contacts: Shumin Zhai, Barton A Smith