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Flight Envelope Load Factor Limit Logic Design for Helicopter Fly-By-Wire Controller
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 Title & Authors
Flight Envelope Load Factor Limit Logic Design for Helicopter Fly-By-Wire Controller
Choi, In-Ho;
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This paper reports the load factor logic design for a fly-by-wire helicopter flight envelope protection. As a helicopter is very complex system with a rotor, fuselage, engine, etc., there are many constraints on the flight region. Because of these constraints, pilots should consider them carefully and have a heavy workload, which causes controllability degradation. In this respect, automatic logic is needed to free the pilot from these considerations. As one of these logics, the flight envelope protection logic for the load factor of a FBW helicopter was designed. The flight to exceed the load factor is caused by an abrupt pitch cyclic stick change. In this scheme, the load factor limit logic was added between the pilot stick command block and pitch attitude command block. From the current load value, the available attitude range was calculated dynamically and simulated on the helicopter simulator model to verify the performance. A comparison of the simulation results at the hovering and forward speed region with and without applying the load limiting logic showed that the load factor limit was exceeded more than 20% when the logic was not applied, whereas with the load factor limit logic the load factor was within the limit. In conclusion, a dynamically allocated limitation logic to helicopter FBW controller was verified by simulation.
ACAH;ADS-33E;Helicopter;Flight control;FBW;
 Cited by
Jeffrey J. Jeram, "Open platform for limit protection with carefree maneuver application", Georgia Institute of Technology, Dec. 2004.

Ilkay Yavrucuk, J.V.R. Prasad, Suraj Unnikrishnan, "Envelope protection for Autonomous unmanned aerial vehicles", Journal of guidance, control, and dynamics, Vol.32, No. 1, January - February 2009.

Ho-Hyun Shin, Sang-Hyun Lee, Youdan Kim, Eung-Tae Kim, and Ki-Jung Sung, "Design of a Flight Envelope Protection System Using a Dynamic Trim Algorithm", Int'l J. Aeronautical & Space Sci. Vol. 12, No. 3, 241-251, 2011 DOI: crossref(new window)

Robert C. Allen and Harry G. Kwatny, "Maneuverability and envelope protection in the prevention of aircraft loss of control", 2011 8th Asian Control Conference, pp. 381-386, May 2011.

W. Falkena, C. Borst, Q.P. Chu, and J. A. Mulder, "Investigation of practical envelope protection systems for small aircraft", J. of Guidance, Control, and Dynamics, Vol. 34, No. 4, pp. 976-988, 2011. DOI: crossref(new window)

In-Ho Choi, Eung-Tai Kim, and Jung-Wook Hyun, "Helicopter FBW Flight Control Law Design for the Handling Quality Performance", Vol. 14, No. 4, pp. 1561-1567, 2013. crossref(new window)