Talks and presentations

Control and Optimization in Multi-agent Systems: A Trilogy

March 20, 2026

Talk, Pennovation Center, Philadelphia, PA

Multi-agent systems are collections of interacting autonomous agents that are becoming increasingly prevalent with the rising popularity of learning-enabled autonomy. Achieving coordinated behavior in collaborative multi-agent settings raises fundamental challenges, including limited or structured communication, complex heterogeneous system architectures, and stringent safety requirements. In this talk, we develop theoretical tools and algorithms that address these challenges across communication, optimization, and safety. First, we leverage applied sheaf theory to model heterogeneous agents and tasks over complex communication topologies, and we propose an asynchronous nonlinear sheaf diffusion method for coordination. Second, we introduce a fully asynchronous momentum-based algorithm that accelerates convergence in parallel optimization without requiring known bounds on communication or computation delays. Finally, we develop a control barrier function (CBF) selection framework with time-varying CBFs called Delta-CBF that preserves safety guarantees while accelerating task completion.

Reactive Swarm Control for Unpredictable Environments

April 15, 2025

Talk, Office of Naval Research (ONR) Program Review (Remote), Atlanta, GA

Control barrier functions (CBFs) are widely used in multi-robot systems to augment control commands to enforce system safety. However, this safety guarantee can come at the cost of slower robot navigation. Therefore, in this work we introduce a framework for using time-invariant CBFs to form a time-varying CBF that guarantees safety while accelerating multi-robot navigation tasks. We first show that a time-varying convex combination of time-invariant CBFs forms a valid time-varying CBF, which renders the time-dependent safe set forward invariant. We also prove that the safe set is uniformly asymptotically stable. Then we introduce an algorithm that alters CBF shapes in real time to accelerate navigation tasks. The performance of the proposed algorithm is validated in hardware experiments in congested multi-robot environments, and it achieves up to a 43% reduction in the time required to complete navigation tasks compared to a baseline time-invariant CBF implementation.