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Comparative Analysis of ACAS-Xu and DAIDALUS Detect-and-Avoid SystemsThe Detect and Avoid (DAA) capability of a recent version (Run 3) of the Airborne Collision Avoidance System-Xu (ACAS-Xu) is measured against that of the Detect and AvoID Alerting Logic for Unmanned Systems (DAIDALUS), a reference algorithm for the Phase 1 Minimum Operational Performance Standards (MOPS) for DAA. This comparative analysis of the two systems' alerting and horizontal guidance outcomes is conducted through the lens of the Detect and Avoid mission using flight data of scripted encounters from a recent flight test. Results indicate comparable timelines and outcomes between ACAS-Xu's Remain Well Clear alert and guidance and DAIDALUS's corrective alert and guidance, although ACAS-Xu's guidance appears to be more conservative. ACAS-Xu's Collision Avoidance alert and guidance occurs later than DAIDALUS's warning alert and guidance, and overlaps with DAIDALUS's timeline of maneuver to remain Well Clear. Interesting discrepancies between ACAS-Xu's directive guidance and DAIDALUS's "Regain Well Clear" guidance occur in some scenarios.
Document ID
Document Type
Technical Memorandum (TM)
Davies, Jason T.
(Universities Space Research Association Moffett Field, CA, United States)
Wu, Minghong G.
(NASA Ames Research Center Moffett Field, CA, United States)
Date Acquired
March 2, 2018
Publication Date
February 1, 2018
Subject Category
Air Transportation And Safety
Report/Patent Number
Funding Number(s)
Distribution Limits
Public Use Permitted.
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