Force and Displacement Preferences for an Alternative Keyboard

Over the past several years, much attention has been given to repetitive strain injuries (RSI’s) in the office environment. Perhaps the most common and widely publicized of these RSI’s is carpal tunnel syndrome (CTS). CTS is an insidious, progressive RSI that affects millions of typists every year. The effects of CTS are far reaching. In the office, CTS reduces worker job satisfaction and productivity which may ultimately affect the company’s bottom line. U.S. businesses spend in excess of $10 billion each year to combat the CTS problem. The AID-CTS keyboard (commercially referred to as the OrbiTouch by Keybowl, Inc.) is an alphanumeric input system that is developed to combat CTS and numerous other upper extremity disabilities. It is designed to offer all typists a more comfortable means of typing and navigation. The purpose of the current study was to determine what combination of dome force and dome displacement were most acceptable to the user. A study was conducted to evaluate different dome forces and different dome displacements using a variable force joystick to establish the most appropriate range of acceptable force and displacement characteristics. The study resulted in an optimum force and displacement that minimizes arm and wrist movements while maximizing user comfort.