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arXiv · 2504.04347

ChronoSync: A Decentralized Chronometer Synchronization Protocol for Multi-Agent Systems

Federico M. Zegers·Sean Phillips
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Abstract

This work presents a decentralized time synchronization algorithm for multi-agent systems. Each agent possesses two clocks, a hardware clock that is perturbed by environmental phenomena (e.g., temperature, humidity, pressure, g forces, etc.) and a steerable software clock that inherits the perturbations affecting the hardware clock. Under these disturbances and the independent time kept by the hardware clocks, our consensus-based controller enables all agents to steer their software-defined clocks into practical synchronization while achieving a common user-defined clock drift. Furthermore, we treat the drift of each hardware clock as an unknown parameter, which our algorithm can accurately estimate. The coupling of the agents is modeled by a connected, undirected, and static graph. However, each agent possesses a timer mechanism that determines when to broadcast a sample of its software time and update its own software-time estimate. Hence, communication between agents can be directed, intermittent, and asynchronous. The closed-loop dynamics of the ensemble is modeled using a hybrid system, where a Lyapunov-based stability analysis demonstrates that a set encoding the time synchronization and clock drift estimation objectives is globally practically exponentially stable. The performance suggested by the theoretical development is confirmed in simulation.

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Federico M. Zegers, Sean Phillips. 2025-04-06. ChronoSync: A Decentralized Chronometer Synchronization Protocol for Multi-Agent Systems. https://arxiv.org/abs/2504.04347

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