CHAPTER 6 ■ ROBOT LINE-FOLLOWING
Even with a basic design, a decent robot still isn’t particularly simple. There’s a lot to learn and a lot to
build. Only after understanding the individual components, circuits, and techniques will you be ready to
combine them into a robot.
This chapter introduces the project goals. The following chapters walk you through component parts
in detail. The line-following robot acts as a context for discussing many of the parts and circuits, but the
part-specific information applies to all robots.
Defining the Course Conditions
By making life easy on the robot, we’ll make life easy on ourselves. Since this is a controlled scientific
experiment, there’s nothing wrong with reducing the environmental factors or variables that the robot is
required to deal with.
Surface Materials
The terrain must be flat and smooth, like a linoleum floor. Also acceptable is short, solid carpeting like
commercial or non-patterned Berber loop-pile. Although softer flooring can reduce the robot’s speed,
the flooring is gentler on the robot’s wheels and any parts that drag. On the other hand, sidewalk concrete
quickly grinds down parts.
Do not permit obstacles, doors, or domesticated animals (including children) to interfere with the
robot’s path.
Course Lighting
Indoor lighting conditions without heavy shadows are essential. Although you can make a robot to handle
both indoor and outdoor driving, you would need additional electronics.
Defining the Line
The width of the line to be followed should average from 1.8 cm to 2.54 cm (from ½ inch to an inch). The
line must contrast well with the floor. Both the line and the floor should be solid colors, not patterns. In fact,
a solid white line on a solid black floor makes the robot happiest (see Figure 6-2). The line and floor must
remain the same color throughout the course.
Figure 6-2. A course made with ordinary masking tape on a flat, dark surface