The Use of Two Fingers to Control Virtual Keyboards with Leap Motion Sensor

Abstract

This research proposes two virtual keyboard designs and two control methods of virtual keyboards. The Keyboard I layout is a $4\times 10$ matrix with QWERTY array keypad and the Keyboard II layout is a $7\times 6$ matrix with alphabet array keypad. Both methods use thumb and index finger only to operate the keyboards. These two fingers can execute five commands: right searching, down searching, selecting character, clearing monitor, and activating the buzzer. The directions of fingers are detected by a Leap Motion sensor. The Algorithm I has two-finger gestures and 4 variables of time. The first gesture is the pointing down index finger with three functions which depends on the time variable: right searching, down searching and clearing monitor. The thumb finger pointing to the inside palm is the second gesture for selecting and activating the buzzer. The algorithm II has one additional gesture, but it has only 3 variables of time. The extra gesture is a slightly left movement of the index finger. This movement is for the down searching. The time variable is only used to clear the monitor and activate the buzzer in the 2nd algorithm. The results showed that algorithm II can reduce the time consumed to type a single character in both keyboard types. The Algorithm I spent approximately 6.7 seconds/character. This number was reduced by Algorithm II into only 5 seconds/character. The Algorithm I had a less finger gesture, but too much time variables confused the user in operating the system. Both algorithms and virtual keyboard designs had successfully been implemented in this research. Those who can just use at least the index finger and thumb would enable them to chat with others by using this application.