Robot Building for Beginners, Third Edition

CHAPTER 6 ■ ROBOT LINE-FOLLOWING

Placing the Robot on the Center of the Line

When positioning the robot, the sensors should be centered over the line (see Figure 6-12). This way, the
amount of light received is equally balanced between the left and right pairs of sensors.

Figure 6-12. Placing the robot with sensors centered on the line

When the robot detects an imbalance of brightness, it knows it’s off center. It then applies power to
either the left or right motor to turn itself until the brightness is balanced again.

Adjusting Sensor Balance

At the front of the robot is a small hole leading to a sensor adjustment dial (see Figure 6-13). A tiny
screwdriver fits into the hole to turn the dial.