Tese de Mestrado, Engenharia Informática, 2023, Universidade de Lisboa, Faculdade de CiênciasMobile touchscreen devices like smartphones or smartwatches are a predominant part
of our lives. They have evolved, and so have their applications. Due to the constant
growth and advancements in technology, using such devices as a means to accomplish a
vast amount of tasks has become common practice.
Nonetheless, relying on touch-based interactions, requiring good spatial ability and
memorization inherent to mobile devices, and lacking sufficient tactile cues, makes these
devices visually demanding, thus providing a strenuous interaction modality for visually impaired people. In scenarios occurring in movement-based contexts or where onehanded use is required, it is even more apparent.
We believe devices like smartwatches can provide numerous advantages when addressing such topics. However, they lack accessible solutions for several tasks, with most
of the existing ones for mobile touchscreen devices targeting smartphones. With communication being of the utmost importance and intrinsic to humankind, one task, in particular, for which it is imperative to provide solutions addressing its surrounding accessibility
concerns is text entry.
Since Braille is a reading standard for blind people and provided positive results in
prior work regarding accessible text entry approaches, we believe using it as the basis for
an accessible text entry solution can help solidify a standardization for this type of interaction modality. It can also allow users to leverage previous knowledge, reducing possible
extra cognitive load. Yet, even though Braille-based chording solutions achieved good
results, due to the reduced space of the smartwatch’s touchscreen, a tapping approach is
not the most feasible. Hence, we found the best option to be a gesture-based solution.
Therefore, with this thesis, we explored and validated the concept and feasibility of
Braille-based shapes as the foundation for an accessible gesture-based smartwatch text
entry method for visually impaired people
