This is a line following Arduino robot I built at Metrix, my local makerspace.
I’ve been taking classes at Metrix. It’s been a great opportunity to work with the Arduino and freshen-up on on my electronics skills. The video is the line-following robot that I built in the last of the series of Arduino classes.
It uses an LED to illuminate the ground in front of it, providing a high contrast surface to sense with a photocell. The Arduino uses the data from the sensor to drive the robot so that it will continue to straddle the line.