Driving a specific distance

For this behavior, we'll use the PI Controller again, and incorporate the distance measurements into our encoder object. We will calculate how many ticks we want the left wheel to have turned for a given distance, and then use this instead of a timeout component.

Refactoring unit conversions into the EncoderCounter class

We'll want the conversions for our encoders in the the EncoderCounter class so that we can use them in these behaviors. Open up your encoder_counter.py class. First, we need the math import:

from gpiozero import DigitalInputDevice
import math
...

At the top of the class, add ticks_to_mm_const as a class variable (not an instance variable) so that we can use it without any...