Vowel-separated layout: a Thai touchscreen keyboard for people with hand movement disability

This paper introduces an approach to improve Thai text entry on virtual keyboards. We propose a word completion on new keyboard layouts called vowel-separated keyboard layouts. Based on a Thai writing system, all vowels locate only four positions i.e. top, bottom, left and right of a consonant. Thus, we design our keyboard layouts by grouping vowels with the same position together and place the vowel group buttons into four positions of keyboard area. This should reduce the searching time when typing vowels. While all consonants still contain in the middle area and the consonant's arrangement is based on standard Thai layout named Kedmanee layout. We design two type of the vowel-separated layouts i.e. distance-based layout and big-button layout. We compare the performance of the proposed layout with the ordinary layout. Both proposed layouts yield better performance than the ordinary one especially the big-button layout. Most of test subjects prefer to use big-button layout because the layout look more simple and they can easily find the character they want.