SOKEYTO v2 : a toolkit for designing and evaluating virtual keyboards

Abstract

Designing virtual keyboards adapted to the needs of upper limbs motor impairment for text input or application control command requires an integrated tool to design and evaluate it. There are platforms of virtual keyboard design. These platforms enable to design virtual keyboards for text input, environment control command but also application control application like Internet. Several studies have defined models and parameters to measure the performance of text entry. Some adjustments of Fitts' law have been proposed to consider the motor behavior of upper limbs motor impairment. This paper will describe the SOftware KEYboard TOolkit (SOKEYTO v2). It is an upgrade of SOKEYTO v1. Text entry and environment controls are available functionalities of software keyboards designed by (SOKEYTO v2). SOKEYTO is the result of brainstorming sessions, review of related work on tools and test of current environment Clavicom NG, CiviKey. SOKEYTO v2 is a complete tool: it enables to design, generate and evaluate software keyboards. The evaluation process is an integral part of SOKEYTO; then it is possible to measure the impact of the layout on speed rate, for example, at each design step of virtual keyboard SOKEYTO v2 also allows the management of multi-layer of software keyboard; each layer could be customized. In regards to related work, SOKEYTO particularities are: predictive models adapted to motor impairment; possibility of customized keyboard layout and a program generator of software keyboard. Firstly, this paper will describe the method used to define the components of SOKEYTO and the characteristics of SOKEYTO with an emphasis on the SOKEYTO particularities. Then, we will report the predictive evaluation of software keyboards designed by the SOKEYTO platform.