Modifying Keyboard Layout to Reduce Finger-Travel Distance

Ample evidence shows that the Qwerty layout is inefficient for one-finger typing on virtual keyboards: letters in common digrams are placed on opposite sides of the keyboard, resulting in an unnecessarily long finger-travel distance. In this paper, we report on using simulated annealing for modifying keyboard layout to reduce finger-travel distance for entering letters of the English alphabet. Our investigation led to improved 3 X 10, 4 X 7, and 5 X 6 layouts, all of which reduced the weighted sum of finger-travel distances for all digrams (denoted by d) by about 40% over Qwerty. The most improved layout is the 5 X 6 layout, which reduces d from 3.31 key widths (the value of d for Qwerty) to 1.78 key widths. These layouts also outperform the best layout reported in the literature.