Multi-Touch: A New Tactile 2-D Gesture Interface for Human-Computer Interaction

The naturalness and variety of a touch-based hand gesture interface offers new opportunities for human-computer interaction. Using a new type of capacitive sensor array, a Multi-Touch Surface (MTS) can be created that is not limited in size, that can be presented in many configurations, that is robust under a variety of environmental operating conditions, and that is very thin. Typing and gesture recognition built into the Multi-Touch Surface allow users to type and perform bilateral gestures on the same surface area and in a smaller footprint than is required by current keyboard and mouse technologies. The present approach interprets asynchronous touches on the surface as conventional single-finger typing, while motions initiated by chords are interpreted as pointing, clicking, gesture commands, or hand resting. This approach requires learning only a few new chords for graphical manipulation, rather than a vocabulary of new chords for typing the whole alphabet. Graphical manipulation seems a better use of chords in today's computing environment.

Comparison of Mouse, Touchpad and Multitouch Input Technologies

Twelve subjects used fixed-angle split keyboards with a conventional mouse, an integrated touchpad, or an integrated MultiTouch surface. Three tasks were tested in each condition: data entry, text editing and cursor positioning. Wrist posture, performance (speed, errors) and subjective ratings were recorded. Results showed that mouse use was fastest for data entry, text editing tasks, and cursor positioning. MultiTouch was faster than the touchpad for cursor positioning, but slower for data entry and text editing. The mouse was rated as easiest to use. MultiTouch and the mouse were rated as more comfortable than the touchpad. There was marginally less wrist extension with use of the MultiTouch or the mouse than with use of the touchpad. Familiarity with keyboard and mouse use may have played a substantial role in the findings.

Effects of a Chair-Mounted Split Keyboard on Performance, Posture and Comfort

In a repeated measures experiment, twelve female typists performed typing and cursor positioning tasks using a chair-mounted split keyboard (FAK) and a conventional keyboard (CK) on an articulated tray. Results showed that the FAK significantly reduced ulnar deviation, but did not reduce wrist extension compared with the CK arrangement. Typing speed was slower for the FAK than the CK, but accuracy was unaffected. Videomotion analysis showed that more subjects sat fully back in their chair with their shoulders relaxed and their hands in less ulnar deviation when using the FAK to type. Other postural changes are described. Subjective comfort and strain ratings are described. Results are discussed within the limitations of a short-term laboratory study.