title: A voice-input voice-output communication aid for people with severe speech impairment.
abstract: A new form of augmentative and alternative communication (AAC) device for people with severe speech impairment-the voice-input voice-output communication aid (VIVOCA)-is described. The VIVOCA recognizes the disordered speech of the user and builds messages, which are converted into synthetic speech. System development was carried out employing user-centered design and development methods, which identified and refined key requirements for the device. A novel methodology for building small vocabulary, speaker-dependent automatic speech recognizers with reduced amounts of training data, was applied. Experiments showed that this method is successful in generating good recognition performance (mean accuracy 96%) on highly disordered speech, even when recognition perplexity is increased. The selected message-building technique traded off various factors including speed of message construction and range of available message outputs. The VIVOCA was evaluated in a field trial by individuals with moderate to severe dysarthria and confirmed that they can make use of the device to produce intelligible speech output from disordered speech input. The trial highlighted some issues which limit the performance and usability of the device when applied in real usage situations, with mean recognition accuracy of 67% in these circumstances. These limitations will be addressed in future work.
authors.affiliation: School of Health and Related Research, University of Sheffield, Sheffield, UK. mark.hawley@sheffield.ac.uk
authors.forename: Mark S
authors.initials: MS
authors.lastname: Hawley
authors.forename: Stuart P
authors.initials: SP
authors.lastname: Cunningham
authors.forename: Phil D
authors.initials: PD
authors.lastname: Green
authors.forename: Pam
authors.initials: P
authors.lastname: Enderby
authors.forename: Rebecca
authors.initials: R
authors.lastname: Palmer
authors.forename: Siddharth
authors.initials: S
authors.lastname: Sehgal
authors.forename: Peter
authors.initials: P
authors.lastname: O'Neill
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001185:Artificial Intelligence; D003143:Communication Devices for People with Disabilities; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013018:Sound Spectrography / Q000295:instrumentation*; D013064:Speech Disorders / Q000534:rehabilitation*; D013068:Speech Production Measurement / Q000295:instrumentation*; D049250:Speech Recognition Software; D016896:Treatment Outcome; D018875:Vocabulary, Controlled