Design of electronic interface and actuators
Fig. 1 depicts the diagram of the sorting system. The images
captured by camera were recalled immediately to the workspace
of Matlab. The detection algorithm identified a stage
of maturity for individual Date fruits within 0.67 s in average.
Then the results from the detection algorithm were sent to the
interface circuit. An optical sensor (Autonics, model BEN5MMFR)
was placed 2–3 cm away from the paddle wheel feeder,
in such a way that it was able to sense the presence of passing
fruit. A signal from the sensor was then sent to the actuator to
activate a paddle wheel feeder in an appropriate time to move
a fruit toward the right exit port. If detected fruit was raw
(Khalal), then step motor 1 opened the normally closed port
and the fruit dropped out of port (Fig. 2). If detected fruit
was semi ripe (Rotab), step motor 2 rotated the paddle wheel
by 90CW (Fig. 2). If the fruit was completely ripe (Tamar),
step motor 2 rotated the paddle wheel 90CCW. Fig. 3 illustrates
the prototype sorting system of Date fruits.