Did you notice?

Wheel Pointers

The white pointers on the EV3's tires help you to see how much the wheels are rotating.

Wheels and Turning

The robot's movement is based on the way the two motors move. The motion you get is determined using different combinations of powers on those motors.

If both motors go forward, the robot moves straight forward as shown in the image below.

 

If both motors run backward, the robot moves straight backward.

 

If they run in opposite directions, the robot spins in place.

 

If the left side moves forward while the right moves back, the robot spins to the right.

 

If the right side moves forward while the left moves back, the robot spins to the left.