Several security elements are necessary, such as alarm and
stop commands, to avoid dangerous situations. These codes can
be generated by means of the blink and alpha waves in EEG
to detect when the eyelids are closed. The automatic wheelchair
system must also be able to navigate in indoor and outdoor environments
and should switch automatically between navigation
modes for these environments. Therefore, this system can be
applied to different navigation modes depending on the degree
of handicap of the user, always using the most efficient technique
for each person. Different support systems have to be used
for avoiding collisions (“bumpers,” ultrasonic and infrared sensors,
etc.) and the robotic system can automatically switch over
to controlling the system in an autonomous way. For example,
if the user loses control and the system becomes unstable, the
wheelchair should stop and take the control of the system.