Single hidden layer neural network based model reference adaptive controller for estimation of periodic disturbances

2019-01-01
Gezer, Rüştü Berk
Kutay, Ali Türker
© 2019 by German Aerospace Center (DLR). Published by the American Institute of Aeronautics and Astronautics, Inc.A model reference adaptive controller effective for systems under periodic disturbances is proposed. The disturbance on the system is assumed to be purely periodic. The parametrization of the adaptive controller uses single hidden layer neural network architecture. The basis functions of this parametrization are formed by elements of Fourier series. The adaptation is done by using a Lyapunov based weight update law which also uses the results of the FFT calculations of the estimated periodic disturbance on the system, as roots of the sigma modification. Proposed adaptation method vary from the adaptation mechanisms discussed in the literature in the following way. First, it takes the disturbance estimation from state-space to time domain, then it carries it to frequency domain. The effectiveness of the method against periodic disturbances is demonstrated through simulations.

Suggestions

Fully transient conjugate analysis of silica-phenolic charing ablation coupled with interior ballistics
Alanyalıoğlu, Çetin Ozan; Özyörük, Yusuf (2019-01-01)
© 2019, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.Due to its excellent insulation capability, usage of silica-phenolic charring ablator as nozzle liner is a common practice in solid rocket motor industry. During the design of a solid rocket motor employing silica-phenolic as nozzle liner, it is desired to conduct an accurate analysis yielding in-depth thermal response and recession characteristics. As the interior ballistics and nozzle recession rate mutually interact...
Multidisciplinary optimization and performance analysis tool for ballistic missiles
Adsız, Mısra Ayşe; Kutay, Ali Türker (2019-01-01)
© 2019 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.During rocket/missile system design process, system design must be made in accordance with military standards, which have very strict rules. Product delivery dates usually are very rigid. Despite this, during conceptual design, requirements are often updated within the design process that requires the design to be updated frequently. It is essential to perform these steps as efficiently and quickly as possible. The pr...
Modeling and controller design of a VTOL air vehicle
Önen, Anıl Sami; Tekinalp, Ozan; Kurtuluş, Dilek Funda; Department of Aerospace Engineering (2015)
This thesis focuses on modeling, controller design, production and flight test of a VTOL unmanned air vehicle. The air vehicle that is designed and manufactured for this study has three propellers. A nonlinear mathematical model of the aircraft is developed. For this both numerical codes as well as wind tunnel tests have been carried out. A simulation code is then written in MATLAB/Simulink environment that describes the physical properties of the system in detail. After trimming the air vehicle at appropri...
Computational fluid dynamics and proper orthogonal decomposition based control of flow over supersonic cavities
Gelisli, Kubra Asena; Aradag, Selin; Tascioglu, Yigit; Özer, Mehmet Bülent (2019-01-01)
© 2019, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.A Computational Fluid Dynamics (CFD) study is conducted to investigate the unsteady, turbulent supersonic cavity flow characteristics and to control the severe effects of the flow field. Simulations of Mach 1.5 supersonic cavity flow with a length to depth ratio of 5.07 are performed using commercial ANSYS Fluent solver. Unsteady density-based Reynolds Averaged Navier-Stokes equations are modeled with standard k-ω turb...
A viscous-inviscid interaction method for 2-D unsteady, compressible flows
Tuncer, İsmail Hakkı; Platzer, Max F. (1993-01-01)
© 1993 American Institute of Aeronautics and Aerodynamics, Inc. All rights reserved.A Navier-Stokes/potential flow interactive solution method suitable for the solution of steady-state and unsteady flowfields around airfoils has been developed. The Navier-Stokes equations are solved in the close proximity of an airfoil and in its wake. The inviscid flowfield surrounding the viscous flow regions is assumed to be irrotational and isentropic. In the inviscid flow region, the potential flow equations, which are...
Citation Formats
R. B. Gezer and A. T. Kutay, “Single hidden layer neural network based model reference adaptive controller for estimation of periodic disturbances,” 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/56252.