IROS 2021: Measurement-Robust Control Barrier Functions: Certainty in Safety with Uncertainty in State

Ryan K. Cosner, Andrew W. Singletary, Andrew J Taylor, Tamas G. Molnar, Katherine L. Bouman, Aaron D. Ames. [pdf]


Abstract:

The increasing complexity of modern robotic systems and the environments they operate in necessitates the formal consideration of safety in the presence of imperfect measurements. In this paper we propose a rigorous framework for safety-critical control of systems with erroneous state estimates. We develop this framework by leveraging Control Barrier Functions (CBFs) and unifying the method of Backup Sets for synthesizing control invariant sets with robustness requirements---the end result is the synthesis of *Measurement-Robust Control Barrier Functions (MR-CBFs)*. This provides theoretical guarantees on safe behavior in the presence of imperfect measurements and improved robustness over standard CBF approaches. We demonstrate the efficacy of this framework both in simulation and experimentally on a Segway platform using an onboard stereo-vision camera for state estimation.

This is work performed in collaboration with Andrew Singletary, Andrew Taylor, Tamas Molnar, Katie Bouman, and Aaron Ames (Caltech). It was originally published at the 2021 IEEE IROS Conference.

The extended publication can be found here (https://arxiv.org/pdf/2104.14030.pdf).