10
Videos and experiment examples:
Videos, literature and other probes can be found
at
Technical background:
The philosophy behind Edu-Logger’s plug and play
technology is based on each sensor’s ability to store its
own data due to an internal flash memory chip and
micro-controller in each plastic Edu-Logger body.
This technology allows the sensor to collect and then
store the digital data in the correct scientific units (
o
C,
o
F, Lux, %, ppm, for example).
The sensor is pre-calibrated at the factory. The built-in
software in the logger can be upgraded at any time
using software.
The
pulse
sensor’s
probe
consists
of
a
fingertip/earlobe clip which houses an infrared light
source and an infrared light detector on opposite sides.
The blood in the finger flows forward (oxygenated
with oxygen) and backward (deoxygenated with CO
2
).
The IR light absorbed by the deoxygenated blood and
the detected light intensity changes are according to
the heart pulses.
The light average intensity changes according to the
skin color, thickness, the probe pressure etc. The
sensor electronics offsets the average intensity,
amplifies and passes the pulses only to the internal
controller, which calculates the pulses' rate.
