title: Usability of a one-hand ternary chord keyboard.
abstract: Five subjects learned to operate a one-hand ternary chord keyboard with 18 different characters, on average, in just over 30 min. Subjects practised inputting numeric-type text for an additional 60 h and attained an average peak keying speed of 170 characters/min. Because of the short learning time, high performance, and low space requirement, the one-hand ternary chord keyboard is an attractive input device for tasks with small character sets.
authors.affiliation: Industrial Ergonomics Laboratory, Human Factors Engineering Center, Industrial and Systems Engineering Department, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0118, USA.
authors.forename: M L
authors.initials: ML
authors.lastname: McMulkin
authors.forename: K H
authors.initials: KH
authors.lastname: Kroemer