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Runtime Analysis with R2U2: A Tool Exhibition Report
Runtime Verification
  • Johann Schumann, NASA Ames Research Center
  • Patrick Moosbrugger, Vienna University of Technology
  • Kristin Yvonne Rozier, Iowa State University
Document Type
Conference Proceeding
The16th International Conference on Runtime Verification
Publication Version
Published Version
Publication Date
Conference Title
The 16th International Conference on Runtime Verification
Conference Date
September 23–30, 2016
(40.4167754, -3.7037901999999576)

We present R2U2 (Realizable, Responsive, Unobtrusive Unit), a hardware-supported tool and framework for the continuous monitoring of safety-critical and embedded cyber-physical systems. With the widespread advent of autonomous systems such as Unmanned Aerial Systems (UAS), satellites, rovers, and cars, real-time, on-board decision making requires unobtrusive monitoring of properties for safety, performance, security, and system health. R2U2 models combine past-time and future-time Metric Temporal Logic, “mission time” Linear Temporal Logic, probabilistic reasoning with Bayesian Networks, and model-based prognostics.

The R2U2 monitoring engine can be instantiated as a hardware solution, running on an FPGA, or as a software component. The FPGA realization enables R2U2 to monitor complex cyber-physical systems without any overhead or instrumentation of the flight software. In this tool exhibition report, we present R2U2 and demonstrate applications on system runtime monitoring, diagnostics, software health management, and security monitoring for a UAS. Our tool demonstration uses a hardware-based processor-in-the-loop “iron-bird” configuration.


This proceeding is published as Schumann J., Moosbrugger P., Rozier K.Y. (2016) "Runtime Analysis with R2U2: A Tool Exhibition Report." The 16th International Conference on Runtime Verification, Madrid, Spain, Sept. 23-30, 2016. In: Falcone Y., Sánchez C. (eds) Runtime Verification. RV 2016. Lecture Notes in Computer Science, vol 10012. DOI: 10.1007/978-3-319-46982-9_35.

Works produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted.
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Citation Information
Johann Schumann, Patrick Moosbrugger and Kristin Yvonne Rozier. "Runtime Analysis with R2U2: A Tool Exhibition Report" Madrid, SpainRuntime Verification (2016) p. 504 - 509
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