Policy Library CBF: Finite-Horizon Safety at Runtime via Parallel Rollouts
- URL: http://arxiv.org/abs/2605.16588v1
- Date: Fri, 15 May 2026 19:45:52 GMT
- Title: Policy Library CBF: Finite-Horizon Safety at Runtime via Parallel Rollouts
- Abstract summary: Policy Library Control Barrier Function(PL-CBF) is a runtime safety filter.<n>Policy Library Control Barrier Function(PL-CBF) is a runtime safety filter.
- Score: 11.99821055563793
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Safety-critical autonomy in unstructured environments poses significant challenges for online safety certification under evolving constraints. We propose Policy Library Control Barrier Function~(PL-CBF), a runtime safety filter that evaluates a library of fallback policies via parallel finite-horizon rollouts, selects the least invasive safe mode, and enforces safety by solving a quadratic program that minimally modifies a nominal policy. We provide a theoretical analysis based on a finite-horizon language metric over closed-loop behaviors, characterizing policy-library coverage requirements for certifying finite-horizon safety. Simulations on a planar double-integrator (4 states), highway driving with abrupt friction changes using a realistic nonlinear vehicle model (8 states), and 3D quadrotor navigation in crowded dynamic environments (12 states) demonstrate improved safety coverage over single-policy safety filters while retaining millisecond-level runtime.
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