Low-cost system based on electro-oculography for communication of disabled people

This paper describes a new low-cost real-time communication assistive system for disabled people, especially those with only eye-motor coordination. The retinal resting potential causes an electric field around the eyeball, centred on the optical axis, which can be measured by placing electrodes near to the eye. An acquisition system was implemented for measuring this potential in order to detect the movement of the eyes and to provide a relative gaze position, making it possible to codify ocular actions as commands. A human-computer interface (HCI) to control the mouse and a virtual screen keyboard, that offers simple setup combined with high performance, have also been developed. This device has multiple applications, especially in assistive research, where control is governed by means of the ocular position (eye displacement in its orbit). The theory behind the device and the hardware and software design of the system are presented.