Robust convex lateral feedback control synthesis for a BWB aircraft

Abstract

This paper presents the robust multi-objective design of a lateral feedback control law for a large flexible blended wing body (BWB) type passenger aircraft. An initial controller is synthesized and optimized using a convex synthesis approach based on the Youla parameterization and an LMI formulation. A multitude of both time-and frequency-domain design constraints are considered aiming to improve disturbance rejection. The obtained control law is numerically validated on several mass cases of the aircraft model, showing high loads alleviation and vibration reduction performance while obeying all stringent design constraints.

Robust lateral blended-wing-body aircraft feedback control design using a parameterized LFR model and DGK-iteration

“…Utilizing the Robust Modal Control Toolbox (see [10]), a low-order output feedback control law is generated which robustly assigns partial eigenstructure speci¦cations (as in [11,18]). An output feedback controller K init of dynamic order 1 is obtained.…”

“…A multitude of stringent constraints and goals are given in the time and frequency domain. An initial controller is designed using robust modal control design [10,11] to achieve some of the goals most closely related to eigenstructure assignment. Based on the preshaped plant, a parameterized high-accuracy LFR is built which serves as basis for robust feedback control design by DGKiteration.…”

“…Previous, closely related studies started on a larger BWB passenger aircraft predesign model: for LQ-based lateral control designs see [13], the application of a genetic algorithm for parameter optimization of a multiobjective H ∞ DK-iteration design has been treated in [14]. Using a Youla parameterization of the feedback control loop, a convex controller synthesis for lateral BWB control has been performed in [11] with a subsequent scheduled feedforward control design in [15]. Longitudinal BWB control using LPV control concepts has been studied in [16].…”

An ℋ∞full information approach for the feedforward controller design of a large blended wing body flexible aircraft

“…Two further convex synthesis approaches for lateral control of a BWB type §exible aircraft are presented in [7,8]. In [8], the focus is on a robust multiobjective feedback design, considering both time-and frequency-domain speci¦cations.…”

“…In [8], the focus is on a robust multiobjective feedback design, considering both time-and frequency-domain speci¦cations. Thereby, signi¦cant reductions of loads and vibrations are obtained.…”