Adding a webcam for autonomous flight
At this point, your quadcopter is controlled by you via a wireless interface. However, you might want to experiment with allowing your quadcopter to control its own flight. Here you'll learn some basic concepts of Proportional-Integrative-Derivative (PID) control to begin exploring this space. There won't be complete or explicit instructions. That would take a book in and of itself. But you can at least get started.
To allow your quadcopter to fly itself, it will need some information about the world around it. One possible way to provide this is to use a webcam and some markers in your flight area. If you followed the instructions in Chapter 1, Preparing the BeagleBone Black, you should have installed all of the software you need in order to add a webcam and view the world around you.
You'll also need to review the concepts from Chapter 4, Vision and Image Processing, for your robotic project. In particular, what you'll want to do...