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The Durham adaptive optics real-time controller was initially a proof of concept design for a generic adaptive optics control system. It has since been developed into a modern and powerful CPU based real-time control system, capable of…

Instrumentation and Methods for Astrophysics · Physics 2010-10-18 Alastair Basden , Deli Geng , Richard Myers , Eddy Younger

L1 adaptive controller has been recognized for having a structure that allows decoupling between robustness and adaption owing to the introduction of a low pass filter with adjustable gain in the feedback loop. The trade-off between…

Systems and Control · Computer Science 2018-09-17 Hashim A. Hashim , Sami El-Ferik , Mohamed A. Abido

In recent decades, one of the scientists' main concerns has been to improve the accuracy of satellite attitude, regardless of the expense. The obvious result is that a large number of control strategies have been used to address this…

Systems and Control · Electrical Eng. & Systems 2022-02-23 Xin Wang , SeyedMehdi Abtahi , Mahmood Chahari , Tianyu Zhao

SPHERE (Spectro Polarimetric High contrast Exoplanet REsearch), the planet finder instrument for the VLT is designed to study relatively bright extrasolar giant planets around young or nearby stars. SPHERE is a set of three instruments fed…

Several approaches have been introduced in literature for active noise control (ANC) systems. Since FxLMS algorithm appears to be the best choice as a controller filter, researchers tend to improve performance of ANC systems by enhancing…

Other Computer Science · Computer Science 2010-04-28 P. Babu , A. Krishnan

Reaching the high angular resolution and contrast level desired for exoplanetary science requires us to equip large telescopes with extreme adaptive optics (XAO) systems to compensate for the effect of the atmospheric turbulence at a very…

Instrumentation and Methods for Astrophysics · Physics 2025-11-20 A. Striffling , C. -T. Héritier , R. J. -L Fétick , O. Fauvarque , J. -F Sauvage , A. Carlotti , B. Neichel T. Fusco

A fractional-order (FO) based controller for a grid-connected PV system is presented in this paper. A single phase two-stage grid-connected photovoltaic generator (PVG) is used to test the performance of the FO controller. The main…

Systems and Control · Electrical Eng. & Systems 2020-04-30 Shah Fahad , Nasim Ullah , Ali Jafer Mahdi , Asier Ibeas , Arman Goudarzi

Adaptive optics (AO) systems and image reconstruction algorithms are indispensable tools when it comes to high-precision astrometry. In this paper, we analyze the potential of combining both techniques, i.e. by applying image reconstruction…

Instrumentation and Methods for Astrophysics · Physics 2019-03-13 Felix Bosco , Jörg-Uwe Pott , Rainer Schödel

Future large space telescopes will be equipped with adaptive optics (AO) to overcome wavefront aberrations and achieve high contrast for imaging faint astronomical objects, such as earth-like exoplanets and debris disks. In contrast to AO…

Instrumentation and Methods for Astrophysics · Physics 2020-01-07 He Sun , N. Jeremy Kasdin , Robert Vanderbei

We propose a design of an adaptive optics (AO) system for the high-resolution fiber-fed echelle spectrograph installed at the Nasmyth focus of the 6-m BTA telescope at the Special Astrophysical Observatory (SAO) of the Russian Academy of…

Instrumentation and Methods for Astrophysics · Physics 2022-08-17 Eduard Muslimov , Gennadiy Valyavin , Vincent Chambouleyron , Felipe Pedreros Bustos , Idir Boudjema

A novel adaptive control approach is proposed to solve the globally asymptotic state stabilization problem for uncertain pure-feedback nonlinear systems which can be transformed into the pseudo-affine form. The pseudo-affine pure-feedback…

Systems and Control · Computer Science 2016-09-29 Mingzhe Hou , Zongquan Deng , Guangren Duan

Adaptive optics (AO) is critical in astronomy, optical communications and remote sensing to deal with the rapid blurring caused by the Earth's turbulent atmosphere. But current AO systems are limited by their wavefront sensors, which need…

Instrumentation and Methods for Astrophysics · Physics 2020-10-23 Barnaby R. M. Norris , Jin Wei , Christopher H. Betters , Alison Wong , Sergio G. Leon-Saval

Input constraints as well as parametric uncertainties must be accounted for in the design of safe control systems. This paper presents an adaptive controller for multiple-input-multiple-output (MIMO) plants with input magnitude and rate…

Optimization and Control · Mathematics 2019-07-30 Joseph E. Gaudio , Anuradha M. Annaswamy , Michael A. Bolender , Eugene Lavretsky

In this paper, we develop a safe control synthesis method that integrates state estimation and parameter estimation within an adaptive optimal control (AOC) and control barrier function (CBF)-based control architecture. The developed…

Systems and Control · Electrical Eng. & Systems 2025-10-24 Tochukwu E. Ogri , Muzaffar Qureshi , Zachary I. Bell , Wanjiku A. Makumi , Rushikesh Kamalapurkar

Cognitive radio (CR) networks face significant challenges in spectrum sensing, especially under spectrum scarcity. Fluid antenna systems (FAS) can offer an unorthodox solution due to their ability to dynamically adjust antenna positions for…

Signal Processing · Electrical Eng. & Systems 2024-11-14 Junteng Yao , Ming Jin , Tuo Wu , Maged Elkashlan , Chau Yuen , Kai-Kit Wong , George K. Karagiannidis , Hyundong Shin

Currently planned second-generation gravitational-wave laser interferometers such as Advanced LIGO exploit the extensively investigated signal-recycling (SR) technique. Candidate Advanced LIGO configurations are usually designed to have two…

General Relativity and Quantum Cosmology · Physics 2009-02-23 Henning Rehbein , Helge Mueller-Ebhardt , Kentaro Somiya , Stefan L. Danilishin , Roman Schnabel , Karsten Danzmann , Yanbei Chen

This paper proposes a novel model-free secondary voltage control (SVC) for microgrids using nonlinear multiple models adaptive control. The proposed method is comprised of two components. Firstly, a linear robust adaptive controller is…

Optimization and Control · Mathematics 2019-12-30 Zixiao Ma , Zhaoyu Wang , Yifei Guo , Yuxuan Yuan , Hao Chen

This paper considers the problem of regulating a linear dynamical system to the solution of a convex optimization problem with an unknown or partially-known cost. We design a data-driven feedback controller - based on gradient flow dynamics…

Optimization and Control · Mathematics 2022-04-05 Liliaokeawawa Cothren , Gianluca Bianchin , Emiliano Dall'Anese

Disturbance rejection in high-precision control applications can be significantly improved upon via online convex optimization (OCO). This includes classical techniques such as recursive least squares (RLS) and more recent, regret-based…

Systems and Control · Electrical Eng. & Systems 2025-04-08 Joyce Lai , Peter Seiler

We investigate methods to calibrate the non-common path aberrations at an adaptive optics system having a wavefront-correcting device working at an extremely high resolution (larger than 150x150). We use focal-plane images collected…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Visa Korkiakoski , Christoph U. Keller , Niek Doelman , Matthew Kenworthy , Gilles Otten , Michel Verhaegen