Bobble-Bot: An educational platform for real-time control with ROS

To help meet the growing needs of the robotics community, the Robot Operating System (ROS) is currently undergoing a major redesign in which one of its primary design goals is to prioritize support for real-time computing (ROS2). Real-time computing techniques are found in most industrial robots, and yet this capability is noticeably lacking from many of the open-source ROS robots in existence today. This knowledge gap is problematic for students using ROS and their future employers with realtime systems requiring development and maintenance. Bobble-Bot is an open-source ROS robot that was created to close this gap. The robot demonstrates the use of real-time control using ROS in a fun and engaging way. Bobble-Bot is a modern example of the classic inverted pendulum problem that is commonly covered in control theory. It is a controls problem that requires a real-time controller to maintain stability. This paper introduces Bobble-Bot and its accompanying simulator in order to demonstrate how to design a real-time system that uses the ROS and ROS2 frameworks. In addition, results from simulation and hardware tests are provided along with links to Bobble-Bot's open-source software and project documentation.