locations which are formed from eyes center and nose
locations. User gaze and blinking gesture are used to provide
the robot direction and different timing commands. The
direction command is related with the movement direction of
electric wheelchair and the timing command is related with
the time condition when the wheelchair should moves. In
[12] another wheelchair model is presented, the authors use
one indoor camera for monitoring wheelchair movement and
another camera on the wheelchair to detect obstacles. A
similar technique uses gaze control is presented in [13] in
which stereo CCD cameras determine the user gaze and its
head pose and a range finder recognizes the surrounding
environment.
In [14] an eye motion tracking hardware that includes a
USB web camera mounted on a cap worn by the user is
presented. This camera is adjusted so that it lies in front of
one of the eye of user. The camera has inbuiIt light source,
so that it can capture bright images if darkness appears under
the cap. The drivers of the camera are installed in a PC to
which the camera is plugged in. The software module for
image processing works on three different modules: video
capturing, frame extraction and pixel color detection. The
image processing program performs these three steps based
on the coherence algorithm. The natural blinks of eye are
distinguished from the unnatural blinks. The user has to
blink his eye for a second if he wants to start moving or stop
moving the wheelchair.
The block diagram shown in Fig. 1 shows the block
diagram of the Eye Controlled Wheelchair used in [15]. The
eye movement is tracked using a camera mounted on to the
headgear. This headgear is interfaced to the laptop/desktop
via USB interface through which real time video of the eye is
sent. The laptop/desktop hosts image processing software
which processes the video feed from the camera and
determines the position of the pupil. The laptop/desktop then
sends signals corresponding to the pupil position to the
micro-controller circuitry which drives the motor