803 KiB
Glossary and Acronyms - Tables
| label | name | description |
|---|---|---|
| ms | \ensuremath{m_s} | Mass of the sample |
| mn | \ensuremath{m_n} | Mass of the nano-hexapod |
| mh | \ensuremath{m_h} | Mass of the micro-hexapod |
| mt | \ensuremath{m_t} | Mass of the micro-station stages |
| mg | \ensuremath{m_g} | Mass of the granite |
| xf | \ensuremath{x_f} | Floor motion |
| ft | \ensuremath{f_t} | Disturbance force of the micro-station |
| fs | \ensuremath{f_s} | Direct forces applied on the sample |
| d | \ensuremath{d} | Measured motion between the nano-hexapod and the granite |
| fn | \ensuremath{f_n} | Force sensor on the nano-hexapod |
| psdx | \ensuremath{Φx} | Power spectral density of signal $x$ |
| asdx | \ensuremath{Γx} | Amplitude spectral density of signal $x$ |
| cpsx | \ensuremath{Φx} | Cumulative Power Spectrum of signal $x$ |
| casx | \ensuremath{Γx} | Cumulative Amplitude Spectrum of signal $x$ |
| key | abbreviation | full form |
|---|---|---|
| haclac | HAC-LAC | High Authority Control - Low Authority Control |
| hac | HAC | High Authority Control |
| lac | LAC | Low Authority Control |
| nass | NASS | Nano Active Stabilization System |
| asd | ASD | Amplitude Spectral Density |
| psd | PSD | Power Spectral Density |
| cps | CPS | Cumulative Power Spectrum |
| cas | CAS | Cumulative Amplitude Spectrum |
| frf | FRF | Frequency Response Function |
| iff | IFF | Integral Force Feedback |
| rdc | RDC | Relative Damping Control |
| drga | DRGA | Dynamical Relative Gain Array |
| rga | RGA | Relative Gain Array |
| hpf | HPF | high-pass filter |
| lpf | LPF | low-pass filter |
| dof | DoF | Degree of freedom |
| svd | SVD | Singular Value Decomposition |
| mif | MIF | Mode Indicator Functions |
| dac | DAC | Digital to Analog Converter |
| fem | FEM | Finite Element Model |
| apa | APA | Amplified Piezoelectric Actuator |
Title Page
Members of the Examination Committee
Prof. Loïc Salles (President of the Committee)≠wline University of Liège (Liège, Belgium)
Prof. Christophe Collette (Supervisor)≠wline University of Liège (Liège, Belgium)
Prof. Olivier Bruls≠wline University of Liège (Liège, Belgium)
Dr. Jonathan Kelly≠wline Diamond Light Source (Oxfordshire, United Kingdom)
Prof. Gérard Scorletti≠wline École Centrale de Lyon, Laboratoire Ampère (Écully, France)
Dr. Olivier Mathon≠wline European Synchrotron Radiation Facility (Grenoble, France)
Abstract
The recent advent of the 4th generation light sources in synchrotron radiation facilities has resulted in X-ray beams that are 100 times more brilliant with the capability to be focused down to smaller, sub-micron sizes. While these advancements open unprecedented scientific opportunities, they simultaneously present significant challenges, especially regarding end-stations that must achieve enhanced sample positioning accuracy and scan speeds.
At the European Synchrotron Radiation Facility (ESRF), the ID31 beamline is equipped with an end-station designed for positioning samples along complex trajectories. A key experimental application is diffraction-tomography, wherein the beam is focused on the sample, which is continuously rotated. However, the accuracy of this end-station is currently limited to the micrometer range due to thermal drifts, mechanical vibrations, and insufficient precision of various mechanical guiding elements. Consequently, it fails to maintain the point of interest of the sample on the focused beam throughout experiments.
This thesis aims to develop a system for actively stabilizing the sample's position in the nanometer range while the end-station executes complex trajectories. The system comprises an external metrology measuring the sample's position, an high dynamic stabilization stage fixed between the end-station and the sample, and dedicated control architecture. The development of such a system presents several challenges that are addressed in this thesis. The first challenge relates to the design methodology. The performance of this complex mechatronic system may be affected by various phenomena. Several dynamical models of increasing complexity and accuracy were employed to predict performance and anticipate design flaws early in the project. This methodical design approach facilitated convergence to a solution that fully satisfies the requirements. The second challenge stems from the control requirements, specifically the need to stabilize samples with masses ranging from 1 to 50 kg, which necessitated the development of specialized control architectures. Finally, experimental validation was performed through the construction and testing of the Nano Active Stabilization System on the ID31 beamline.
The thesis demonstrates the feasibility of enhancing the positioning performance of an existing end-station through the implementation of an active stabilization system, thereby contributing to the advancement of experimental capabilities in synchrotron radiation facilities.
\begingroup ≤t\clearpage\relax \chapter*{Résumé} \endgroup
Résumé
Acknowledgments
First and foremost, I would like to express my deepest gratitude to my advisor, Professor Christophe Collette, for his constant support throughout this journey. His ability to challenge my thinking and dedication to mentoring my growth as a researcher has been invaluable. His door was always open, and he generously shared his time and expertise, providing feedback and guidance at every stage of the research process. Our discussions during the regular journeys between Liege and Brussels laboratories transformed routine travel into moments of scientific inspiration. His passion and dedication for research were truly inspiring, and I could not have wished for a better advisor.
I am honored that Professor Loïc Salles accepted the role of president of the jury for this thesis. My sincere appreciation goes to my thesis committee members, Professor Olivier Bruls and Professor Jean-Claude Golinval, for following my work and providing insightful advice through the years.
I extend my gratitude to the jury members: Dr. Jonathan Kelly, Professor Gérard Scorletti, Dr. Olivier Mathon and Professor Olivier Bruls for their willingness to participate in the examination committee of this doctoral thesis. Their time, expertise, and careful consideration of my work are greatly appreciated.
My time at the Precision Mechatronics Laboratory during the first two years of this project was enriched by interesting discussions and collaborations with Ahmad, Mohit, Jennifer, Vicente, Guoying, and Haidar. I am particularly grateful for the opportunity to have worked alongside such talented and dedicated individuals. Thank you, my friends, for making my stay in Belgium such a wonderful memory.
The subsequent five years at the ESRF were made possible by several key individuals: Veijo Honkimaki (ID31's Scientist), Michael Krish (Head of the Instrumentation Division), Philippe Marion (Head of the Mechanical Engineering Group), and Muriel Magnin-Mattenet (Mechanical Engineer in charge of ID31). I especially want to acknowledge their efforts in providing me with the resources, facilities, and technical expertise necessary to conduct my research at the ESRF.
The technical aspects of this work benefited greatly from various collaborations. I am grateful for the fruitful collaboration on mechanical design with Julien Bonnefoy and Damien Coulon. Special thanks to Philipp Brumund for his invaluable Finite Element Analysis expertise and constant encouragement to complete my PhD thesis. I am especially thankful to Marc Lesourd for introducing me to the world of vibration measurements and modal analysis, and Noel Levet for our interesting discussions about dimensional metrology and his tremendous support with the alignment of the developed instrument. The remarkable technical support from Pierrick Got and Kader Amraoui in electronics allowed smooth implementation of the developed system on the ID31 beamline. I also thank Hans Peter and Ludovic for granting me access to the outstanding mechatronics laboratory at the ESRF.
I am grateful to the master thesis students I had the chance to supervise: Adrien Jublan for his work on multi-body modelling, Youness Benyaklhef for his contribution to the metrology system and Caio Belle for his research on multi-variable control.
Finally, my profound thanks go to my family and close friends. To my father, who inspired me to pursue research, and my mother, whose unwavering support has been precious beyond words. And to Juliette, for being incredibly supportive through the inevitable tough times that are part of the PhD journey.
Reproducible Research
Grants
Table of Contents
Introduction
<<chap:introduction>>
Conclusion and Future Work
<<chap:conclusion>>
Bibliography
List of Publications
Glossary
Footnotes
1DLPVA-100-B from Femto with a voltage input noise is $2.4\,nV/\sqrt{\text{Hz}}$ 2Mark Product L-22D geophones are used with a sensitivity of $88\,\frac{V}{m/s}$ and a natural frequency of $\approx 2\,\text{Hz}$ 3Mark Product L4-C geophones are used with a sensitivity of $171\,\frac{V}{m/s}$ and a natural frequency of $\approx 1\,\text{Hz}$
4As this matrix is in general non-square, the Moore–Penrose inverse can be used instead. 5NVGate software from OROS company. 6OROS OR36. 24bits signal-delta ADC. 7Kistler 9722A2000. Sensitivity of $2.3\,mV/N$ and measurement range of $2\,kN$ 8PCB 356B18. Sensitivity is $1\,V/g$, measurement range is $\pm 5\,g$ and bandwidth is $0.5$ to $5\,\text{kHz}$.
9It was probably caused by rust of the linear guides along its stroke. 10Laser source is manufactured by Agilent (5519b). 11The special optics (straightness interferometer and reflector) are manufactured by Agilent (10774A). 12C8 capacitive sensors and CPL290 capacitive driver electronics from Lion Precision. 13The Spindle Error Analyzer is made by Lion Precision. 14The tools presented here are largely taken from cite:&taghirad13_paral. 15Rotations are non commutative in 3D. 16Ball cage (N501) and guide bush (N550) from Mahr are used. 17Modified Zonda Hexapod by Symetrie. 18Made by LAB Motion Systems. 19HCR 35 A C1, from THK.
20Such equation is called the velocity loop closure 21The pose represents the position and orientation of an object 22Different architecture exists, typically referred as "6-SPS" (Spherical, Prismatic, Spherical) or "6-UPS" (Universal, Prismatic, Spherical)
23Cedrat technologies 24The manufacturer of the APA95ML was not willing to share the piezoelectric material properties of the stack.