New possibilities for enhanced keyboard input for the handicapped

Motor- and speech-impaired people can have severe problems with communication. If speech is hampered, the use of computerized communication devices can be a solution. Key entry limitations due to motor impairments may result in very low communication speeds--less than three words a minute is not unusual. The research described here deals with speed enhancement on the basis of redundancy in language. Two uses are explored: prediction and automatic decoding in the case of keyboards with a small number of keys. Prediction means that characters, words and (parts of) sentences are predicted on the basis of text which is already typed in. A prototype system is being designed which combines the features of the PAL prediction system from Dundee and the WRITE-keyboard from Boston. Decoding refers to two-step selection systems with a small number of keys in which the second selection is done automatically by a computer program. Keystroke savings of 40 to 50% are possible.