Aim:
Our object is to make an autonomous robot that can follow a white lined path placed over a black background. If the robot goes out of track then it senses the black region and return to the white line. The white path may take a turn and robot follows it.
Principle:
The robot consists of two light detecting sensors (LDR) paired with LEDs. The LEDs continuously emits light. When the robot is on white line, the light sent by LEDs is reflected back and received by LDRs, so that the robot moves forward. If a sensor come to black region then no light is reflected back to the LDR.
Motion of White line tracer:
When left sensor comes in black region then right motor stops while left motor continue to move so that right turn takes place and robot returns on white line. When right sensor comes in black region then left motor stops while right motor continue to move so that left turn takes place and robot returns on white line.
When both sensors are on white line then robot moves forward. The same concept helps to take a turn.
Our White line tracer:
