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Sensors 5

TYPICALLY ROBOTIC SENSORS MIMIC BIOLOGICAL SENSES
like hearing, sight, touch, smell, and taste. Balance and body posi-
tion derived from the inner ear are sometimes considered a sixth
sense. Biological senses are neurally based, while robotic senses
are electrically based. One could argue the point that they are
both electrically based by pointing out that both the neural path-
ways and signals pass an electrochemical signal. However, neural 59
sensors function differently than electrically based sensors. So,
not to confuse technologies, it’s important to define them as elec-
trically based.

If one wants to truly imitate biological senses, neural sensors are
needed. The human ear is an example of a neural sensor. Let’s ex-
amine it. The human ear is not a linear instrument. Its response to
sound is logarithmic. Because of this, a tenfold increase in sound
intensity is only perceived by the human ear as a doubling of
sound volume. In contrast, a common sound sensor, for instance,
a microphone, has a linear response to sound intensity. There-
fore, a tenfold increase in sound intensity is read by a computer
(microcontroller or electronic circuit) as a tenfold increase in
sound intensity.
Sensors detect and/or measure an aspect of the environment and
can produce a proportional electrical signal. The signal information
must then be read or interpreted by the intelligence [central pro-
cessing unit (CPU)] or neural network on the robot. Although we
may categorize the sensors as they relate to human senses, sensors
are typically divided by the type of energy that the sensor responds

Team LRN Sensors

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