Block Diagram

The robot uses IR sensors to sense the line, an array of 8 IR LEDs (Tx) and sensors (Rx), facing the ground has been used in this setup. The output of the sensors is an analog signal which depends on the amount of light reflected back, this analog signal is given to the comparator to produce 0s and 1s which are then fed to the µC.

Left Center Right

Sensor Array

Starting from the center, the sensors on the left are named L1, L2, L3, L4 and those on the right are named R1, R2, R3, R4.

Let us assume that when a sensor is on the line it reads 0 and when it is off the line it reads 1

The µC decides the next move so as to position the robot such that L1 and R1 both read 0 and the rest read 1.

Left Center Right

Desired State L1=R1=0, and Rest=1

Algorithm: (more…)