12 papers
Robust Adaptive Backup Control Barrier Functions
Ersin Daş, David E. J. van Wijk, Tamas G. Molnar +2
We propose a notion of robust adaptive backup control barrier functions for nonlinear control affine systems with parametric uncertainty in both the drift dynamics and actuation ma…
Output Feedback Backup Control Barrier Functions: Safety Guarantees Under Input Bounds and State Estimation Error
David E. J. van Wijk, Tamas G. Molnar, Samuel Coogan +3
Guaranteeing the safety of controllers is vital for real-world applications, but is markedly difficult when the states are not perfectly known and when the control inputs are bound…
Safety Guardrails in the Sky: Realizing Control Barrier Functions on the VISTA F-16 Jet
Andrew W. Singletary, Max H. Cohen, Tamas G. Molnar +1
The advancement of autonomous systems -- from legged robots to self-driving vehicles and aircraft -- necessitates executing increasingly high-performance and dynamic motions withou…
Integral Control Barrier Functions with Input Delay: Prediction, Feasibility, and Robustness
Adam K. Kiss, Ersin Das, Tamas G. Molnar +1
Time delays in feedback control loops can cause controllers to respond too late, and with excessively large corrective actions, leading to unsafe behavior (violation of state const…
Generalizations of Backup Control Barrier Functions: Expansion and Adaptation for Input-Bounded Safety-Critical Control
David E. J. van Wijk, Dohyun Lee, Ersin Das +3
Guaranteeing the safety of nonlinear systems with bounded inputs remains a key challenge in safe autonomy. Backup control barrier functions (bCBFs) provide a powerful mechanism for…
Enforcing Mixed State-Input Constraints with Multiple Backup Control Barrier Functions: A Projection-based Approach
Laszlo Gacsi, Adam K. Kiss, Ersin Das +1
Ensuring the safety of control systems often requires the satisfaction of constraints on states (such as position or velocity), control inputs (such as force), and a mixture of sta…
Braking within Barriers: Constructive Safety-Critical Control for Input-Constrained Vehicles via the Backup Set Method
Laszlo Gacsi, Adam K. Kiss, Tamas G. Molnar
This paper presents a safety-critical control framework to maintain bounded lateral motions for vehicles braking on asymmetric surfaces. We synthesize a brake controller that assis…
Safety-Critical Control with Bounded Inputs: A Closed-Form Solution for Backup Control Barrier Functions
David E. J. van Wijk, Ersin Das, Tamas G. Molnar +2
Verifying the safety of controllers is critical for many applications, but is especially challenging for systems with bounded inputs. Backup control barrier functions (bCBFs) offer…
Activated Backstepping with Control Barrier Functions for the Safe Navigation of Automated Vehicles
Laszlo Gacsi, Max H. Cohen, Tamas G. Molnar
This paper introduces a novel safety-critical control method through the synthesis of control barrier functions (CBFs) for systems with high-relative-degree safety constraints. By…
Navigating Polytopes with Safety: A Control Barrier Function Approach
Tamas G. Molnar
Collision-free motion is a fundamental requirement for many autonomous systems. This paper develops a safety-critical control approach for the collision-free navigation of polytope…
Uncertainty Estimators for Robust Backup Control Barrier Functions
David E. J. van Wijk, Ersin Das, Anil Alan +5
Designing safe controllers is crucial and notoriously challenging for input-constrained safety-critical control systems. Backup control barrier functions offer an approach for the…
A Learning-Based Framework for Safe Human-Robot Collaboration with Multiple Backup Control Barrier Functions
Neil C. Janwani, Ersin Daş, Thomas Touma +3
Ensuring robot safety in complex environments is a difficult task due to actuation limits, such as torque bounds. This paper presents a safety-critical control framework that lever…