Overcoming Speech Barriers: Non-Verbal Voice Cue Interaction Technique for Enhancing Smart Voice Assistant Accessibility for Individuals with Dysarthria

Inclusive user experience design that caters to a broad range of users can enhance the ease of interaction with systems. Despite progress, certain systems like smart voice assistants often remain inaccessible to some user types, particularly individuals with dysarthria whose speech may not be recognized by these devices. In this article, we present a novel interaction technique that relies on non-verbal voice cues instead of words and sentences. To evaluate the usability, user experience, and workload of this approach, we developed a system (DARIA) and conducted two studies, exploring two different design options. The first study tested the system without a customization option, while the second introduced a customization option. We used three questionnaires and conducted post-study interviews for thorough evaluation. The findings indicated user acceptance of this interaction technique in general was high. When compared with a market leader product (Alexa), DARIA showed higher performance in terms of accessibility. Users found the non-verbal system to be more usable and likable. Interestingly, the customizable design was found less usable than the pre-defined.