This document proposes an eye tracking interpretation system to help paralyzed or physically disabled people communicate. It uses a Raspberry Pi 2 with a CMOS camera and IR sensor to track eye movements via the corneal reflection and pupil center method. The system analyzes eye-related measurements and potentially other physiological signals to interpret the user's intentions and provide a natural interface without need for physical input devices. It was designed to enable communication through eye movements alone.

1. EYE TRACKING INTERPRETATION SYSTEM
Applications
References
Conclusion
Problem Statement
As Paralyzed/physically disabled people couldn’t
convey their messages to others, hence build a
system to communicate themselves to the outside
world
Objective
To track and Interpret Eye Movements with Human
Computer Interaction by using corneal-
reflection/pupil-centre method and also by tracing the
gaze reflections.
Software & Hardware
Software Hardware
Open CV Raspberry Pi 2
Raspbian CMOS Camera
IR Sensor
Methodology
Future Scope
•Eye-related measurements such as the pupil size and
microsaccades can be used for interpretation.
• It can also be combined with other measurements
from the user’s face and body, enabling multimodal
physiological computing.
•It can offer a ate the user in a smart way interface
that complements the user’s natural behavior.
Introduction
• Eye tracking is a technique whereby an individual’s
eye movements are measured so that we come to
know that where a person is looking at any given
time and the sequence in which their eyes are
shifting from one location to another.
• Eye-movement recordings can provide an objective
source of interface-evaluation data that can inform
the design of improved interfaces.
• Eye movements can also be captured and used as
control signals to enable people to interact with
interfaces directly without the need for mouse or
keyboard input, which can be a major advantage for
certain populations of users such as disabled
individuals.
•Can be used by paralyzed/physically disabled people for
communication purpose.
•Marketing research and Medical research (neurological
diagnosis).
•The car industry does research in this field too, with the aim of
developing assistant systems for cars. For example, an eye
tracker in the car could warn the driver when she or he falls
asleep while driving the car.
•Specific applications include the tracking eye movement in
language reading, music reading, human activity recognition, the
perception of advertising.
•Video-based eye tracking, provides a fairly
comfortable non-invasive (contact-free) option
for the users.
•Systems that combine the video with infrared (i.e.
track both the pupil and the IR corneal reflection)
also provide reasonable freedom of head movement
without sacrificing the accuracy too much.
•We use “corneal-reflection/pupil-centre” method in this there will be processor infrared them easier to track.
•The light enters the retina and a large proportion of it is reflected back, making the CMOS camera mounted beneath a
display monitor with Open CV locate and identify the features of the eye used for tracking ,the infrared LED are located on
camera is first directed into the eye to create strong reflections in target eye features to make pupil appear as a bright, well
defined disc (known as the “bright pupil” effect).The corneal reflection is also generated by the infrared light, appearing as a
small, but sharp and glint .
•Once the image processing software has identified the centre of the pupil and the location of the corneal reflection the
vector between them is measured.
•Video-based eye trackers need to be fine-tuned to the particularities of each person’s eye movements by a “calibration”
process. This calibration works by displaying a dot on the screen, and if the eye fixes for longer than a certain threshold time
and within a certain area, the system records that pupil-centre/corneal-reflection relationship as corresponding to a specific
x,y coordinate on the screen.
• Alex Poole and Linden J. Ball.
Eye Tracking in Human-Computer Interaction and
Usability Research: Current Status and Future
Prospects
Block Diagram