@inproceedings{90d888f64d844027a7ad3aa63ac8c9f4,
title = "Load alleviation using direct load feedback with extremum seeking control",
abstract = "This work presents an alleviation control system for the rotorcraft pitch link load based on the dynamic inversion controller using direct load feedback and extremum seeking control to regulate the load. The proposed method is applied to a compound utility rotorcraft with similar airframe properties as a UH-60A along with lifting wings. The nonlinear model is developed in FLIGHTLAB{\textregistered} from where the vehicle dynamics and critical fatigue loads are extracted as a linear time-periodic system due to its cyclic nature. Via harmonic decomposition, this model is converted to a high-order linear time-invariant (LTI) system and then a reduced-order method is applied to extract a more tractable system for controller design over a range of airspeeds. The design is tested in both, the high-order LTI and the nonlinear system. The results present a significant reduction in the pitch link peak-to-peak loads with a minimum change in the response characteristics.",
author = "Mariano Scaramal and Horn, {Joseph F.}",
note = "Funding Information: This research was partially funded by the U.S. Government under agreement no. W911 W6-17-2-0003. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Aviation Development Directorate or the U.S. Government. Publisher Copyright: {\textcopyright} 2022, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.; AIAA AVIATION 2022 Forum ; Conference date: 27-06-2022 Through 01-07-2022",
year = "2022",
doi = "10.2514/6.2022-3281",
language = "English (US)",
isbn = "9781624106354",
series = "AIAA AVIATION 2022 Forum",
publisher = "American Institute of Aeronautics and Astronautics Inc, AIAA",
booktitle = "AIAA AVIATION 2022 Forum",
}