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1. Mashrafi, Sheikh. X-ray microscope performance enhancement through control architecture change.

Degree: MS, 0133, 2014, University of Illinois – Urbana-Champaign

The goal of this thesis is to apply control algorithms to improve the performance of nanopositioning devices used on the beamline in Advanced Photon Source (APS) at Argonne National Laboratory (ANL). A prototype device, better known as the Early User Instrument (EUI) was the subject of this work. It consists of X-ray optics stage group that focuses the X-ray beam as a source-size-limited spot onto a sample held on the sample stage group. The controller algorithms that are used should provide the closed-loop with robust stability, large bandwidth, high resolution, disturbance rejection and noise attenuation. Conveniently, the field of scanning probe microscopes (SPMs) have already flourished on this aspect of controller algorithms proven to give desired closed-loop properties. Controller algorithms such as Proportional Integral Derivative (PID), Glover-McFarlane H-infinty algorithm, and 1DOF H-infinty controller were designed and implemented on the EUI system. The controller hardware used for implementation is National Instruments (NI) CompactRIO hardware that consists of a real-time controller, a FPGA built into the hardware chassis, analog I/O modules, and digital I/O modules. NI LabVIEW, the dedicated software to the NI hardware, was used to represent the discrete controllers as biquads structures that ran in the FPGA as a part of the closed-loop . The largest closed-loop bandwidth achieved is of 65 Hz through the 1DOF H-infinty controller and is a 171% improvement over the traditional PID controller. Highest closed- loop resolution achieved by the EUI with a 50 Hz bandwidth 1DOF H-infinty controller is 1.4 nanometers, which is a 180% improvement over the open loop resolution of 7 nanometers. Advisors/Committee Members: Salapaka, Srinivasa M. (advisor), Preissner, Curt (advisor).

Subjects/Keywords: control; Control Architecture; Advanced Photon Source (APS); Argonne National Laboratory (ANL); control algorithms; nanopositioning; nanopositioning devices; Early User Instrument (EUI); X-ray; optics; robust stability; bandwidth; resolution; disturbance rejection; noise attenuation; scanning probe microscope (SPM); closed-loop properties; Proportional Integral Derivative (PID); Glover-McFarlane h-infinity algorithm; 1DOF h-infinity controller; h-infinity; Glover-McFarlane controller; Keith Glover; Duncan McFarlane; controller; controller implementation; National Instruments (NI); CompactRIO; real-time controller; Field-Programmable Gate Array (FPGA); LabVIEW; biquads structures; closed-loop bandwidth; U.S. Department of Energy (DOE); Office of Science; DE-AC02-06CH11357; DE-SC0004283; Cross Power Spectral Density (CPSD); Power Spectral Density (PSD); Degree Of Freedom (DOF); Discrete-Time Fourier Transform (DTFT); Hardware Description language (HDL); High-Level Synthesis (HLS); Hard X-ray Nanoprobe (HXN); In Situ Nanoprobe (ISN); Laser Doppler Displacement Meter (LDDM); Physik Instrumente (PI); Reconfigurable Input/Output (RIO); Advanced Photon Source (APS) beamline; full-field imaging microscopy; fluorescence mapping; nanodiffraction; transmission imaging; reliability and repeatability of positioning systems; modeling uncertainties; insensitive modeling uncertainties; quantifying trade-offs; trade-offs; design flexibility; design methodology; feedforward; feedback; performance objectives; robustness; Advanced Photon Source (APS) user; beamline scientist; imaging resolution and bandwidth; imaging resolution; nanoprobe; model fitting; curve fitting; model reduction; feedback controllers; X-ray nanoprobe instrument; third-generation synchrotron radiation source; zone plate optics; zone plate; flexure stages; piezoelectric actuators stacks; flexure; Piezoelectric; high-stiffness stages; high-resolution weak-link stages; piezoelectric-transducer; sub-nanometer resolution; subnanometer; optical heterodyning; heterodyning; Optodyne; frequency-shifted laser beam; PID controller; digital to analog converter (DAC); analog input modules; digital input modules; analog output modules; cRIO-9118; Virtex-5; Virtex-5 LX110 FPGA chassis; NI-9223; NI-9402; NI-9263; System Identification; Identification; black-box identification; parametric model; non-parametric model; welch; pwelch; tfestimate; invfreqs; time domain data; band-limited uniform Gaussian white noise; band-limited; white noise; resonant peak; Balance Realization; minimal realization; controllability; observability; Experimental Frequency response; transfer function; Hankel singular values; Hankel norm; balanced truncation; noise histogram; Open Loop Resolution; closed Loop Resolution; Simulink simulation; LabVIEW simulation; discrete controller; continuous controllers; discrete; Tustin; tustins method; discretization; complementary sensitivity transfer function; sensitivity transfer function; robust stabilization; coprime factorization; Bezout identity; Bezout; stability margin; algebraic Riccati equation; Riccati equation; sub-optimal; suboptimal; sub-optimal controller; optimal controller; mixed-sensitivity optimization; sensitivity optimization; generalized framework; generalized controller framework; stabilizing controller; closed-loop objectives; generalized plant; nominal plant; linear fractional transformation; weighting transfer functions; weighted sensitivity; hinfsyn; bode integral law; waterbed effect; second waterbed formula; Skogestad; Poslethwaite; sensitivity weighting; sensitivity weighting transfer function; nanopositioner; nanopositioning device; nanopositioning system; second order sections; ASPE 28th Annual Meeting; American Society for Precision Engineering (ASPE); Synchrotron Radiation Instrumentation; Synchrotron; Nanoprobe Instrument

…estimated PSD for each segmented data, and then averages this PSD estimates. The pwelch function… 

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Mashrafi, S. (2014). X-ray microscope performance enhancement through control architecture change. (Thesis). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/46671

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Mashrafi, Sheikh. “X-ray microscope performance enhancement through control architecture change.” 2014. Thesis, University of Illinois – Urbana-Champaign. Accessed December 07, 2019. http://hdl.handle.net/2142/46671.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Mashrafi, Sheikh. “X-ray microscope performance enhancement through control architecture change.” 2014. Web. 07 Dec 2019.

Vancouver:

Mashrafi S. X-ray microscope performance enhancement through control architecture change. [Internet] [Thesis]. University of Illinois – Urbana-Champaign; 2014. [cited 2019 Dec 07]. Available from: http://hdl.handle.net/2142/46671.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Mashrafi S. X-ray microscope performance enhancement through control architecture change. [Thesis]. University of Illinois – Urbana-Champaign; 2014. Available from: http://hdl.handle.net/2142/46671

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.