Código
You can find the code for the line follower here. After uploading the code, sweep/move the sensor array over the black line from left to right for roughly 3 seconds. This is done in order to calibrate and find the max and min values for reflectance. After that, place the robot on the line and watch the bot follow it. If you're using the Pololu QTR-8A reflectance array sensor, then no significant changes may be required. Try to check the values coming from the sensor through the serial monitor. Based on those values, adjust the values in the code correspondingly.
For those who made the custom board, find the rough values of reflectance over the black line and the outer surface. Substitute these values in the code and calibrate it. You can use normal black insulation tape as the line for your robot to follow. See the line follower in action below.
