A human computer interface operated with head-movements, eye-movements & eye-blinks

A method for a real-time hands-free communication system is presented. The system is able to use two different signals to control cursor movement over a computer screen: (1) the person's direction of gaze and, (2) the person's head movements. The creation of an innovative algorithm, allows an efficient and accurate determination of gaze position. This algorithm is a real-time approach that combines eye position data and head position data to output the direction of the user's line of sight. Eye movements are measured with a pupil-corneal reflection device and head movements are measured with a magnetic tracking system.; Another important feature of the interface is its ability to detect and classify the user's eye closures as either involuntary blinks or voluntary eye closures. The purpose of this algorithm is to emulate the personal computer's mouse clicks. Voluntary blinks are used to trigger mouse clicks and therefore, enable interaction. The presence of a voluntary eye-blink is declared when the duration of a blink event surpasses an experimental pre-fixed time value. Preliminary tests suggest that the system is capable of being used as an alternative input modality for the purpose of human computer interaction.