This is a single PCB small line following robot. However, it also has the ability to control with Bluetooth.

Basically, it is a robot designed to follow the line and automatically deliver the object to its destination. This robot uses a closed-loop system to follow the track accurately.

These IR sensors are mounted on the lower part of the robot which tracks the line and moves towards its destination according to the received input. In this line track robot i uses the HC-05 Bluetooth Module . This module receives input from the smartphone and functions according to commands received from the user.

Line sensors are nothing but an active IR sensor. It consists of a transmitter and a receiver. The transmitter is nothing but an IR source, which emits IR rays continuously and when these rays collide with an object, these rays return from there to the module. An IR detector mounted on the sensor captures those reflected rays and these signals are then delivered to the micro-controller which detects the presence of the object based on the instruction the programmer has stored in the program memory.

For the line follower sensor, we are using black tape and we have patched it onto the reflective surface. When the IR light falls on the black tape, the IR rays will be absorbed from the surface and if those rays fall on the reflective surface then it will reflect back to the sensor and in this way, by calculating the reflected signals we will decide whether the robot is on the track or not.