Augmentative and Alternative Communication systems for the motor disabled

This chapter discusses Augmentative and Alternative Communication (AAC) for individuals with motor disabilities. Motor disabilities do not only affect movement, but very often also affect speech. In these cases where voice is very weak, speech is unintelligible, or motor problems in the human speech production systems do not allow a person to speak, AAC is introduced. Aided and unaided communication is explained, and low and high tech AAC examples are illustrated. The ITHACA framework for building AAC applications is used as a paradigm in order to highlight the AAC software lifecycle. The same framework is also used to highlight AAC software design issues concerning component-based development (the open source model and the Design for All principles). Key features of an AAC application like virtual keyboards, scanning techniques, symbol dashboards, symbolic communication systems, message editors, symbol translation, word prediction, text to speech, and remote communication are presented. Finally, practical hints for choosing an AAC system are given and a case study of informally evaluating it is cited.