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248 CHAPTER 7 ■ NAVIGATION

In the next section, I will discuss how I can reduce some of the errors relating to positional
inaccuracy by giving the robot the ability to know where it is absolutely in an environment.
This process is called localization.

7.2 Localization

Localization is the process of giving the robot the ability to position itself in its environment. In
the last chapter, the robot was able to move in a vector, but this vector had no start point, and
its end point had large amounts of error because of environmental factors like wheel slippage,
errors in conversion, and so on. In this section, I’ll show you how to reduce this error by using
sonar to calculate a start and an end position.
To begin, I am going to set the environment of the robot to be in a Perfect World as defined
in the last section. This is a 100-inch × 100-inch grid with no obstacles. (See Figure 7-9.)

Figure 7-9. Perfect World

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