Design and Developing Methodology for 8-dot Braille Code Systems

Braille code, employing six embossed dots evenly arranged in rectangular letter spaces or cells, constitutes the dominant touch reading or typing system for the blind. Limited to 63 possible dot combinations per cell, there are a number of application examples, such as mathematics and sciences, and assistive technologies, such as braille displays, in which the 6-dot cell braille is extended to 8-dot. This work proposes a language-independent methodology for the systematic development of an 8-dot braille code. Moreover, a set of design principles is introduced that focuses on: achieving an abbreviated representation of the supported symbols, retaining connectivity with the 6-dot representation, preserving similarity on the transition rules applied in other languages, removing ambiguities, and considering future extensions. The proposed methodology was successfully applied in the development of an 8-dot literary Greek braille code that covers both the modern and the ancient Greek orthography, including diphthongs, digits, and punctuation marks.