Safety and Efficiency in Robotics: The Control Barrier Functions Approach

This paper aims at presenting an introductory overview of the theoretical framework of Control Barrier Func- tions (CBFs) and of its application to the design of safety-related controllers for robotic systems. The article starts by describing the basic concepts of CBFs and how they can be used to build optimization problems embedding CBF-based constraints, whose solution corresponds to the control input enforcing desired safety properties into the behavior of the controlled system. Simple examples, understandable for readers with a basic background in control theory and accompanied with source code for their simulation, are used to highlight the appealing features of the CBF-based approach. Then, more complex formulations applicable to robotic manipulators are introduced, recalling recent literature results allowing to implement a robust design methodology. Finally, it is shown that CBFs are suitable for the implementation of safe human-robot collaboration in a realistic industrial scenario, by means of the experimental validation in an industrial setup for collaborative robotics.