Circuit diagram

Make a line follower robot can be done with two transistors. Line Follower Robot series is one of the two transistors contor robot line follower circuit is in Bagun with two NPN transistor and the motor driver as well as processing of sensor signals.


In the circuit of line follower robot consists of two parts of the same, only different functions for the motor driver the right and left. Sensor circuit of line follower robot uses the LDR and LED. LDR sensor sensitivity can be set with the VR 10 is mounted in series with the LDR. For more details, see the following figure.

The working principle of the motor driver circuit between the right and left together, when the LDR get the reflection of light from the LED LDR resistance will decrease and make the transistor saturation and motor gets supply and rotates so that the robot moves forward. So at the moment is not the case then the motor did not get a supply, for example, only one sensor is exposed line and make the LDR did not receive the reflected light is then Motr in the stationary and the other motor rotates and makes the LDR are back in the reflection of light and the robot moves forward again.