Virtual Compact Two-Thumbs QWERTY Keyboard for Blind and Vision Impaired Users

Abstract

Physical keyboard are the most favourite input devices for text data, but for mobile devices and terminals, it becomes difficult to use physical keyboards to input data. Therefore, virtual keyboards become an ultimate choice for such devices. Due to small screen size, it is also not desirable to have full sized standard virtual keyboard, so compact virtual keyboard with few numbers of keys  an essential choice for mobile devices or terminals to improve typing as well as use mobile screen efficiently. Use of QWERTY layout with compact designs gives more accurate typing as compare to other layouts. Compact design with QWERTY layout is implemented with different keys combinations and key events to improve the typing experience. In this proposed virtual compact keyboard design, a QWERTY layout is suggested with limited number of keys with various key combinations and key events such as tapping, long press, and fling. It also manages the screen size effectively with few keys to utilize minimum of the screen size, as well as having enough size keys to reduce invalid key errors. It also offers sight-free typing and can be an effective solution for blinds and vision impaired users. Blinds and vision impaired users can easily type text with less movement of thumb and shows improved WPM rate with low typing errors. The proposed virtual compact keyboard design is tested for usability evaluation by measuring functionality, efficiency, and satisfaction using After Scenario Questionnaire (ASR) and shows an overall effectiveness of 75.93% for vision impaired users as compare to 44.44% for totally blind users. The overall satisfaction results show 4.7 out of 7 score in operating the application by vision impaired and blind users. The results also shows the expected improvement in WPM rate in next iteration of same task.