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Autonomy Levels for Unmanned Systems (ALFUS) Framework Volume I: Terminology Version 2.0



Hui-Min Huang


This document identifies and defines terms to support the system (UMS) community, particularly from the perspectives of characterizing the autonomy and measuring the autonomous capability of the UMS. This document, Version 2.0 of the Autonomy Levels for Unmanned Systems (ALFUS) Terminology is based on Version 1.1 that was published in 2004 as NIST Special Publication 1011. This work is a collective effort of the Ad Hoc ALFUS Working Group. The Group later formed the Performance Measures Subcommittee of the Society of Automotive Engineers (SAE) AS-4 Unmanned Systems Committee
Special Publication (NIST SP) - 1011
Report Number


autonomy, control, environment, human independence, human robot interaction, measurement, metrics, mission, robot, unmanned system


Huang, H. (2004), Autonomy Levels for Unmanned Systems (ALFUS) Framework Volume I: Terminology Version 2.0, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed July 21, 2024)


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Created September 30, 2004, Updated November 10, 2018