PATHFINDER Contd....PART 2

Input system:

Line sensor module:


LED PHOTRANSISTOR pair

Each sensor module consists of one emitter (LED) and one receiver (Photo transistor).
If white surface is present beneath the LED, rays are reflected and are sensed by the receiver phototransistor’s base, the phototransistor gets on.
While in case of black surface, the light gets absorbed and hence receiver phototransistor become off.
Thus the presence of white and black surface is sensed by the sensor module and the system can follow a line.

IR obstacle sensor module::

IR LED for emitter IR photodiode for receiver

The obstacle sensor consists of one emitter (IR LED) and one receiver (IR Photo diode).
If obstacle is present the IR rays are reflected back and are sensed by the receiver photo diode, the photo diode gets forward biased (on).
While in case of no obstacle, the IR rays don’t get reflected back and hence receiver photo diode become reverse biased (off).
Thus the presence of obstacle is sensed by the sensor module.


CONTD.........