EV3 is a robotics sets from LEGO Mindstorms. With EV3 you could build an infinite number of robots like Vehicles, Animals and Tanks. The set comes in two parts - base set (45544) and a resource set (45560). EV3 robots are very popular at LEGO Mindstorms Robotics Competitions
Umjaho - from the language of the Zulu tribe. It means "competition"
This LEGO Mindstorms EV3 robot has three sensors - touch, color and ultrasonic. When the touch sensor is pressed the robot starts moving. The color sensor is used for following lines and the ultrasonic sensor is used to detect any robots in front of the robot.
This is the simplest possible line following robot. It has just one sensor in the front between the two driving wheels and uses beams as pivots instead of a third wheel. Try it out. Follow the building instructions and start following lines in a number of minutes.