Use of harmonic decomposition models in rotorcraft flight control design with alleviation of vibratory loads

Umberto Saetti, Joseph Francis Horn

Research output: Chapter in Book/Report/Conference proceedingConference contribution

5 Citations (Scopus)

Abstract

An Explicit Model Following (EMF) control scheme is designed to achieve stability and desired Rate Command / Attitude Hold (RCAH) response around the roll, pitch and yaw axes, while alleviating vibratory loads through both feed-forward and feedback compensation. First, the effect of command model tailoring is explored to understand the effect of feed-forward compensation on vibratory loads, with a focus on the main rotor pitch links. Secondly, the harmonic decomposition methodology is extended to enable optimization of primary flight control laws that mitigate vibratory loads. Specifically, Linear Time Periodic (LTP) systems representative of the periodic rotorcraft dynamics are approximated by Linear Time Invariant (LTI) models, which are then reduced and used in LQR design to constrain the harmonics of the vibratory loads. The gains derived are incorporated in the EMF scheme for feedback compensation. Finally, simulation results with and without load alleviation are compared and the impact of feed-forward and feedback compensation on handling qualities Is assessed in terms of ADS-33E specifications.

Original languageEnglish (US)
Title of host publication43rd European Rotorcraft Forum, ERF 2017
PublisherAssociazione Italiana di Aeronautica e Astronautica (AIDAA)
Pages391-400
Number of pages10
Volume1
ISBN (Print)9781510865389
StatePublished - Jan 1 2017
Event43rd European Rotorcraft Forum, ERF 2017 - Milan, Italy
Duration: Sep 12 2017Sep 15 2017

Other

Other43rd European Rotorcraft Forum, ERF 2017
CountryItaly
CityMilan
Period9/12/179/15/17

Fingerprint

vibratory loads
rotary wing aircraft
flight control
Decomposition
harmonics
decomposition
commands
Feedback
linear quadratic regulator
yaw
Time varying systems
controllability
rotors
specifications
Rotors
methodology
Specifications
optimization
Compensation and Redress
simulation

All Science Journal Classification (ASJC) codes

  • Control and Systems Engineering
  • Aerospace Engineering
  • Instrumentation
  • Electrical and Electronic Engineering

Cite this

Saetti, U., & Horn, J. F. (2017). Use of harmonic decomposition models in rotorcraft flight control design with alleviation of vibratory loads. In 43rd European Rotorcraft Forum, ERF 2017 (Vol. 1, pp. 391-400). Associazione Italiana di Aeronautica e Astronautica (AIDAA).
Saetti, Umberto ; Horn, Joseph Francis. / Use of harmonic decomposition models in rotorcraft flight control design with alleviation of vibratory loads. 43rd European Rotorcraft Forum, ERF 2017. Vol. 1 Associazione Italiana di Aeronautica e Astronautica (AIDAA), 2017. pp. 391-400
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Saetti, U & Horn, JF 2017, Use of harmonic decomposition models in rotorcraft flight control design with alleviation of vibratory loads. in 43rd European Rotorcraft Forum, ERF 2017. vol. 1, Associazione Italiana di Aeronautica e Astronautica (AIDAA), pp. 391-400, 43rd European Rotorcraft Forum, ERF 2017, Milan, Italy, 9/12/17.

Use of harmonic decomposition models in rotorcraft flight control design with alleviation of vibratory loads. / Saetti, Umberto; Horn, Joseph Francis.

43rd European Rotorcraft Forum, ERF 2017. Vol. 1 Associazione Italiana di Aeronautica e Astronautica (AIDAA), 2017. p. 391-400.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Saetti U, Horn JF. Use of harmonic decomposition models in rotorcraft flight control design with alleviation of vibratory loads. In 43rd European Rotorcraft Forum, ERF 2017. Vol. 1. Associazione Italiana di Aeronautica e Astronautica (AIDAA). 2017. p. 391-400