Tiltrotor whirl-flutter stability analysis using the maximum Lyapunov characteristic exponent estimated from time series

Tiltrotor whirl-flutter stability analysis using the maximum Lyapunov characteristic exponent estimated from time series

Gianni Cassoni, Alessandro Cocco, Aykut Tamer, Andrea Zanoni, Pierangelo Masarati

Abstract. Stability analysis and assessment are fundamental in the analysis and design of dynamical systems. Particularly in rotorcraft dynamics, problems often exhibit time-periodic behavior, and modern designs consider nonlinearities to achieve a more accurate representation of the system dynamics. Nonlinearities in rotorcraft may arise from factors such as nonlinear damper constitutive laws or the influence of fluid-structure interaction, among others. Regardless of their origin, quantifying the stability of nonlinear systems typically relies on calculating their Jacobian matrix. However, accessing the Jacobian matrix of a system is often challenging or impractical, calling for the use of data-driven methods. This introduces additional complexity in capturing the characteristic dynamics of the system. Hence, a data-driven approach is proposed that utilizes the Largest Lyapunov Characteristic Exponent, obtained by analyzing the system’s time series.

Keywords
Lyapunov Characteristic Exponents, Whirl-Flutter, Stability, Multibody Dynamics, Jacobian-Less Methods

Published online 11/1/2023, 4 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Gianni Cassoni, Alessandro Cocco, Aykut Tamer, Andrea Zanoni, Pierangelo Masarati, Tiltrotor whirl-flutter stability analysis using the maximum Lyapunov characteristic exponent estimated from time series, Materials Research Proceedings, Vol. 37, pp 30-33, 2023

DOI: https://doi.org/10.21741/9781644902813-7

The article was published as article 7 of the book Aeronautics and Astronautics

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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