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a robust direct-integration method for rotorcraft maneuver and periodic responseThe Newmark-Beta method and the Newton-Raphson iteration scheme are combined to develop a direct-integration method for evaluating the maneuver and periodic-response expressions for rotorcraft. The method requires the generation of Jacobians and includes higher derivatives in the formulation of the geometric stiffness matrix to enhance the convergence of the system. The method leads to effective convergence with nonlinear structural dynamics and aerodynamic terms. Singularities in the matrices can be addressed with the method as they arise from a Lagrange multiplier approach for coupling equations with nonlinear constraints. The method is also shown to be general enough to handle singularities from quasisteady control-system models. The method is shown to be more general and robust than the similar 2GCHAS method for analyzing rotorcraft dynamics.
Document ID
19930026922
Document Type
Reprint (Version printed in journal)
Authors
Panda, Brahmananda
(McDonnell Douglas Helicopter Co. Mesa, AZ, United States)
Date Acquired
August 15, 2013
Publication Date
July 1, 1992
Publication Information
Publication: American Helicopter Society, Journal
Volume: 37
Issue: 3
ISSN: 0002-8711
Subject Category
AIRCRAFT STABILITY AND CONTROL
Funding Number(s)
CONTRACT_GRANT: NAS2-12340
Distribution Limits
Public
Copyright
Other