Virtual keyboard applications and alternative communication devices provide new means of communication to assist disabled people. To date, virtual keyboard optimization schemes based on script-specific information,along with multimodal input access facility, are limited.In this paper, we propose a novel method for optimizing the position of the displayed items for gaze-controlled tree based menu selection systems by considering a combination of letter frequency and command selection time.The optimized graphical user interface layout has been designed for a Hindi language virtual keyboard based on a menu wherein 10 commands provide access to type 88 different characters, along with additional text editing commands. The system can be controlled in two different modes: eye-tracking alone and eye-tracking with an access soft-switch. Five different keyboard layouts have been presented and evaluated with ten healthy participants. Furthermore, the two best performing keyboard layouts have been evaluated with eye-tracking alone on ten stroke patients.The overall performance analysis demonstrated significantly superior typing performance,high usability (87% SUS score), and low workload (NASA TLX with 17 scores) for the letter frequency and time-based organization with script specific arrangement design. This paper represents the first optimized gaze-controlled Hindi virtual keyboard, which can be extended to other languages.
|Number of pages||12|
|Journal||IEEE Transactions on Neural Systems and Rehabilitation Engineering|
|Early online date||12 Mar 2018|
|Publication status||E-pub ahead of print - 12 Mar 2018|
- Gaze tracking
- human computer interaction
- graphical user interfaces
- optimization methods
- performance evaluation.