On transferring safety certificates across dynamical systems

TL;DR

This paper introduces a transferred control barrier function framework that enables safety guarantees to be transferred between different dynamical systems, even with mismatched models, using simulation functions and safety filters.

Contribution

The paper presents a novel transferred control barrier function approach that handles model mismatch and applies to systems with different dynamics and dimensions.

Findings

Successfully enforced collision avoidance on a quadrotor with mismatched dynamics.

The transferred barrier effectively accounts for model mismatch and maintains safety.

The approach is general and minimally invasive to existing controllers.

Abstract

Control barrier functions (CBFs) provide a powerful tool for enforcing safety constraints in control systems, but their direct application to complex, high-dimensional dynamics is often challenging. In many settings, safety certificates are more naturally designed for simplified or alternative system models that do not exactly match the dynamics of interest. This paper addresses the problem of transferring safety guarantees between dynamical systems with mismatched dynamics. We propose a transferred control barrier function (tCBF) framework that enables safety constraints defined on one system to be systematically enforced on another system using a simulation function and an explicit margin term. The resulting transferred barrier accounts for model mismatch and induces a safety condition that can be enforced on the target system via a quadratic-program-based safety filter. The proposed approach is general and does not require the two systems to share the same state dimension or dynamics. We demonstrate the effectiveness of the framework on a quadrotor navigation task with the transferred barrier ensuring collision avoidance for the target system, while remaining minimally invasive to a nominal controller. These results highlight the potential of transferred control barrier functions as a general mechanism for enforcing safety across heterogeneous dynamical systems.