Design of safety monitor schemes for a fault tolerant flight control system

• Published in: IEEE transactions on aerospace and electronic systems Vol. 42; no. 2; pp. 562 - 571
• Main Authors: Perhinschi, M.G., Napolitano, M.R., Campa, G., Seanor, B., Burken, J., Larson, R.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.04.2006; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Aerospace control; Aerospace safety; Aerospace simulation; Air safety; Aircraft; Computer simulation; Computerized monitoring; Design engineering; Fault tolerance; Fault tolerant; Fault tolerant systems; Flight control systems; Flight simulation; Logic testing; Mathematical models; NASA; Safety; System testing
• ISSN: 0018-9251; 1557-9603
• DOI: 10.1109/TAES.2006.1642572

For a research aircraft, "conventional" control laws (CLs) are implemented on a "baseline" flight computer (FC) while research CLs are typically housed on a dedicated research computer. Therefore, for an experimental aircraft used to test specific fault tolerant flight control systems, a safety logic scheme is needed to ensure a safe transition from conventional to research CLs (while at nominal conditions) as well as from research CLs at nominal conditions to conditions with "simulated" failures on specific control surfaces. This paper describes the design of such a safety scheme for the NASA Intelligent Flight Control System (IFCS) F-15 Program. The goals of the IFCS F-15 program are to investigate the performance of a set of fault tolerant CLs based on the use of dynamic inversion with neural augmentation. The different transitions are monitored using information relative to flight conditions and controller-related performance criteria. The testing of the scheme is performed with a Simulink-based flight simulation code and interface developed at West Virginia University for the NASA IFCS F-15 aircraft.