This HoneyBot exactly follows the line using Line Follower Array Sensor.You might have known about this sensor and the concept of line follower as well as how to code it if you have completed our Advance Level. And also they are using Ultrasonic Sensor for obstacle detection, you might have learned this concept in the Expert Level.
Isn't it amazing that we can also build mini HoneyBot with our Kits in Advance Level and the Expert Level?Build more honeybots :P like this :)
Source: Engadget