Model-Free Safety-Critical Control for Robotic Systems

Tamás G. Molnár, Ryan K. Cosner, Andrew W. Singletary, Wyatt Ubellacker, Aaron D. Ames

Abstract: This letter presents a framework for the safety-critical control of robotic systems, when safety is defined on safe regions in the configuration space. To maintain safety, we synthesize a safe velocity based on control barrier function theory without relying on a – potentially complicated – high-fidelity dynamical model of the robot. Then, we track the safe velocity with a tracking controller. This culminates in <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">model-free safety critical control</i> . We prove theoretical safety guarantees for the proposed method. Finally, we demonstrate that this approach is application-agnostic. We execute an obstacle avoidance task with a Segway in high-fidelity simulation, as well as with a Drone and a Quadruped in hardware experiments.