Using BeagleBone Blue to build an Autopilot Robot (part 1) – Circuit Cellar article

Hi folks! My name is Pedro Bertoleti and I’m a software engineer from Brazil.

The October issue of Circuit Cellar’s magazine came out yesterday (9/18/2018), and I’ve written one of the articles of this issue (Title: “Building an Autopilot Robot (part 1)”, page 16). This article shows the groundwork for reliable  speed estimation based in the accelerometer measurements and uses this speed in a PID controller to make an Autopilot system for a 4-wheel robot.

This project uses as development kit the amazing BeagleBone Blue, a board focused on robotics projects usage.

Autopilot Robot – project features

This project consists of two main features:

  • Reliable speed estimation based on accelerometer measurements. The accelerometer I used is the one present in IMU chip of BeagleBone Blue board (no extra/external sensors needed).
  • PID Speed control. Using the estimated speed, an Autopilot control is made for the 4-wheel robot. This speed control is a PID control, implemented in robot’s software. No extra/external circuits required (I used all motor-driving circuits present on BeagleBone Blue board).

Robot control library was widely used in this project software and all software was written in C language, in order to achieve the best performance possible.

Concepts and approaches covered by this article

This article (part 1 of “Building an Autopilot Robot” article series) covers the following concepts and approaches:

  • Digital Signal Processing techniques to go from raw accelerometer measures to reliable speed estimation, detailed explained with equations, graphics step-by-step explanation and all results achieved discussed
  • Robot Control Library usage: wisely reading sensors and controlling DC Motors.
  • PID control from the scratch

What’s next

The part 2 of this article (to be released next month) will merge all the concepts and approaches shown in part 1, in order to build the real robot prototype. Also, all robot prototype data (speed and PID control accurate) will be shown in graphical and numerical forms and analysed/discussed, in order to prove the project works as expected.

For those who like Internet of Things, there’re two more very interesting things too: the setup of autopilot remotely, using Internet and the telematics of robot’s speed over Internet.

Useful links