Vol. 8 No. 2 (2022): Special Issue on Distributed Hybrid Systems
Special Issue on Distributed Hybrid Systems

Real-Time Verification for Distributed Cyber-Physical Systems

Hoang-Dung Tran
University of Nebraska-Lincoln, Lincoln, Nebraska, USA
Luan Viet Nguyen
University of Dayton, Dayton, Ohio, USA
Patrick Musau
Vanderbilt University, Nashville, Tennessee, USA
Weiming Xiang
Augusta University, Nashville, Tennessee, USA
Taylor T. Johnson
Vanderbilt University, Nashville, Tennessee, USA

Published 2022-12-07


  • Verification,
  • Reachability Analysis,
  • Distributed Cyber-Physical Systems

How to Cite

Tran, H.-D., Nguyen, L.V., Musau, P., Xiang, W. and Johnson, T.T. 2022. Real-Time Verification for Distributed Cyber-Physical Systems. Leibniz Transactions on Embedded Systems. 8, 2 (Dec. 2022), 07:1–07:19. DOI:https://doi.org/10.4230/LITES.8.2.7.


Safety-critical distributed cyber-physical systems (CPSs) have been found in a wide range of applications. Notably, they have displayed a great deal of utility in intelligent transportation, where autonomous vehicles communicate and cooperate with each other via a high-speed communication network. Such systems require an ability to identify maneuvers in real-time that cause dangerous circumstances and ensure the implementation always meets safety-critical requirements. In this paper, we propose a real-time decentralized reachability approach for safety verification of a distributed multi-agent CPS with the underlying assumption that all agents are time-synchronized with a low degree of error. In the proposed approach, each agent periodically computes its local reachable set and exchanges this reachable set with the other agents with the goal of verifying the system safety. Our method, implemented in Java, takes advantages of the timing information and the reachable set information that are available in the exchanged messages to reason about the safety of the whole system in a decentralized manner. Any particular agent can also perform local safety verification tasks based on their local clocks by analyzing the messages it receives. We applied the proposed method to verify, in real-time, the safety properties of a group of quadcopters performing a distributed search mission.


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