外乱に頑健なバックアップ制御バリア関数：不確かなダイナミクス下での安全性
Disturbance-Robust Backup Control Barrier Functions: Safety Under Uncertain Dynamics
外乱を含む非線形システムに対し、ノミナル系の周囲に拡張するノルム球チューブの安全性を保証することで、オンラインで前方不変集合を構成するDR-bCBFを提案した。
著者: David E. J. van Wijk, Samuel Coogan, Tamas G. Molnar, Manoranjan Majji, Kerianne L. Hobbs
分類: eess.SY, cs.RO, cs.SY, math.DS
原文アブストラクト
Obtaining a controlled invariant set is crucial for safety-critical control with control barrier functions (CBFs) but is non-trivial for complex nonlinear systems and constraints. Backup control barrier functions allow such sets to be constructed online in a computationally tractable manner by examining the evolution (or flow) of the system under a known backup control law. However, for systems with unmodeled disturbances, this flow cannot be directly computed, making the current methods inadequate for assuring safety in these scenarios. To address this gap, we leverage bounds on the nominal and disturbed flow to compute a forward invariant set online by ensuring safety of an expanding norm ball tube centered around the nominal system evolution. We prove that this set results in robust control constraints which guarantee safety of the disturbed system via our Disturbance-Robust Backup Control Barrier Function (DR-bCBF) solution. The efficacy of the proposed framework is demonstrated in simulation, applied to a double integrator problem and a rigid body spacecraft rotation problem with rate constraints.
