The final module for our line-following robot is This program initiates the pipes that will instantiate the,, and programs as separate processes using multiple Popen() functions. It provides a minimal user-text-mode interface, provides the logic to handle button functions, and most importantly provides the logic to steer the robot.


The following shows the steps to download as well as the explanation of the code's functionality:

  1. Use the command line to open a new instance of the Python 2 IDLE (it does not need to have root privilege).
  2. Download from the Chapter 8 folder at
  3. Open in the Python IDE (non-privileged). ...

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