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An iterative-based feedforward-feedback control approach to high-speed atomic force microscope imaging / Ying Wu in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N° 6 (Novembre 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N° 6 (Novembre 2009) . - 09 p. Titre : An iterative-based feedforward-feedback control approach to high-speed atomic force microscope imaging Type de document : texte imprimé Auteurs : Ying Wu, Auteur ; Qingze, Zou, Auteur Année de publication : 2010 Article en page(s) : 09 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : atomic  force  microscopy;  design;  errors;  feedback;  feedforward  control;  imaging;  iterative  learning  control Résumé : This article presents an iterative-based feedforward-feedback control approach to achieve high-speed atomic force microscope (AFM) imaging. AFM-imaging requires precision positioning of the probe relative to the sample in all x-y-z axes directions. Particularly, this article is focused on the vertical z-axis positioning. Recently, a current-cycle-feedback iterative-learning-control (CCF-ILC) approach has been developed for precision tracking of a given desired trajectory (even when the desired trajectory is unknown), which can be applied to achieve precision tracking of sample profile on one scanline. In this article, we extend this CCF-ILC approach to imaging of entire sample area. The main contribution of this article is the convergence analysis and the use of the CCF-ILC approach for output tracking in the presence of desired trajectory varation between iterations—the sample topography variations between adjacent scanlines. For general case where the desired trajectory variation occurs between any two successive iterations, the convergence (stability) of the CCF-ILC system is addressed and the allowable size of desired trajectory variation is quantified. The performance improvement achieved by using the CCF-ILC approach is discussed by comparing the tracking error of using the CCF-ILC technique to that of using feedback control alone. The efficacy of the proposed CCF-ILC control approach is illustrated by implementing it to the z-axis control during AFM-imaging. Experimental results are presented to show that the AFM-imaging speed can be substantially increased. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/Issue.aspx?issueID=26505&di [...] [article] An iterative-based feedforward-feedback control approach to high-speed atomic force microscope imaging [texte imprimé] / Ying Wu, Auteur ; Qingze, Zou, Auteur . - 2010 . - 09 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N° 6 (Novembre 2009) . - 09 p. Mots-clés : atomic  force  microscopy;  design;  errors;  feedback;  feedforward  control;  imaging;  iterative  learning  control Résumé : This article presents an iterative-based feedforward-feedback control approach to achieve high-speed atomic force microscope (AFM) imaging. AFM-imaging requires precision positioning of the probe relative to the sample in all x-y-z axes directions. Particularly, this article is focused on the vertical z-axis positioning. Recently, a current-cycle-feedback iterative-learning-control (CCF-ILC) approach has been developed for precision tracking of a given desired trajectory (even when the desired trajectory is unknown), which can be applied to achieve precision tracking of sample profile on one scanline. In this article, we extend this CCF-ILC approach to imaging of entire sample area. The main contribution of this article is the convergence analysis and the use of the CCF-ILC approach for output tracking in the presence of desired trajectory varation between iterations—the sample topography variations between adjacent scanlines. For general case where the desired trajectory variation occurs between any two successive iterations, the convergence (stability) of the CCF-ILC system is addressed and the allowable size of desired trajectory variation is quantified. The performance improvement achieved by using the CCF-ILC approach is discussed by comparing the tracking error of using the CCF-ILC technique to that of using feedback control alone. The efficacy of the proposed CCF-ILC control approach is illustrated by implementing it to the z-axis control during AFM-imaging. Experimental results are presented to show that the AFM-imaging speed can be substantially increased. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/Issue.aspx?issueID=26505&di [...]

Design and Control of Optimal Scan Trajectories: Scanning Tunneling Microscope Example / Perez, Hector in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 126 N° 1 (Mars 2004) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 126 N° 1 (Mars 2004) . - 187-197 p. Titre : Design and Control of Optimal Scan Trajectories: Scanning Tunneling Microscope Example Titre original : Conception et Commande de Trajectoire Optimale de Balayage : Exemple de Balayage de Microscope de Perçage d'un Tunnel Type de document : texte imprimé Auteurs : Perez, Hector, Auteur ; Qingze, Zou, Auteur ; Devasia, Santosh Article en page(s) : 187-197 p. Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Conception  optimale  Trajectoire  de  balayage  Microscope  de  perçage  Trajectoire  optimale  Trajectoire  de  rendement Index. décimale : 629.8 Résumé : This article addresses the optimal (minimal input energy) design of scan trajectories, which is important in applications such as the imaging and manipulation of nano-scale surface phenomena using scanning tunneling microscopes (STM), MEMS-based micro-scanners, quick-return mechanisms and cams used in manufacturing, and general repeating processes. The contribution of this article is the systematic solution of the optimal scan-trajectory design problem. As opposed to existing techniques that require pre-specification of the desired output trajectory (such prespecifications can be ad hoc), the optimal output trajectory is found as a result of the proposed input-energy minimization approach. In this sense, the proposed approach leads to a systematic solution of the optimal output-trajectory-design problem. The proposed optimal scanning method is applied to an experimental scanning tunneling microscope; simulation and experimental results are presented to illustrate the efficacy of the proposed approach to design optimal scan-trajectories. Cet article adresse la conception optimale (d'énergie minimale d'entrée) de la trajectoire de balayage, qui est importante dans les applications telles que la formation image et la manipulation de nano-mesurent les phénomènes extérieurs à l'aide des microscopes de perçage d'un tunnel de balayage (STM), les modules de balayage micro MEMS-basés, les mécanismes rapides et les cames de retour utilisés à la fabrication, et le général répétant des processus. La contribution de cet article est la solution systématique du problème optimal de conception de trajectoire de balayage. Par opposition aux techniques existantes qui exigent des pré-spécifications de la trajectoire désirée de rendement (de tels prespecifications peuvent être ad hoc), la trajectoire optimale de rendement est trouvée en raison de l'approche proposée de minimisation d'énergie d'entrée. Dans ce sens, l'approche proposée mène à une solution systématique du problème optimal de conception de trajectoire de rendement. La méthode optimale proposée de balayage est appliquée à un microscope expérimental de perçage d'un tunnel de balayage ; la simulation et les résultats expérimentaux sont présentés pour illustrer l'efficacité de l'approche proposée pour concevoir la trajectoire optimale de balayage. En ligne : hperez@upbbga.edu.co, qzouatuw@u.washington.edu, devasia@u.washington.edu [article] Design and Control of Optimal Scan Trajectories: Scanning Tunneling Microscope Example = Conception et Commande de Trajectoire Optimale de Balayage : Exemple de Balayage de Microscope de Perçage d'un Tunnel [texte imprimé] / Perez, Hector, Auteur ; Qingze, Zou, Auteur ; Devasia, Santosh . - 187-197 p. Génie Mécanique Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 126 N° 1 (Mars 2004) . - 187-197 p. Mots-clés : Conception  optimale  Trajectoire  de  balayage  Microscope  de  perçage  Trajectoire  optimale  Trajectoire  de  rendement Index. décimale : 629.8 Résumé : This article addresses the optimal (minimal input energy) design of scan trajectories, which is important in applications such as the imaging and manipulation of nano-scale surface phenomena using scanning tunneling microscopes (STM), MEMS-based micro-scanners, quick-return mechanisms and cams used in manufacturing, and general repeating processes. The contribution of this article is the systematic solution of the optimal scan-trajectory design problem. As opposed to existing techniques that require pre-specification of the desired output trajectory (such prespecifications can be ad hoc), the optimal output trajectory is found as a result of the proposed input-energy minimization approach. In this sense, the proposed approach leads to a systematic solution of the optimal output-trajectory-design problem. The proposed optimal scanning method is applied to an experimental scanning tunneling microscope; simulation and experimental results are presented to illustrate the efficacy of the proposed approach to design optimal scan-trajectories. Cet article adresse la conception optimale (d'énergie minimale d'entrée) de la trajectoire de balayage, qui est importante dans les applications telles que la formation image et la manipulation de nano-mesurent les phénomènes extérieurs à l'aide des microscopes de perçage d'un tunnel de balayage (STM), les modules de balayage micro MEMS-basés, les mécanismes rapides et les cames de retour utilisés à la fabrication, et le général répétant des processus. La contribution de cet article est la solution systématique du problème optimal de conception de trajectoire de balayage. Par opposition aux techniques existantes qui exigent des pré-spécifications de la trajectoire désirée de rendement (de tels prespecifications peuvent être ad hoc), la trajectoire optimale de rendement est trouvée en raison de l'approche proposée de minimisation d'énergie d'entrée. Dans ce sens, l'approche proposée mène à une solution systématique du problème optimal de conception de trajectoire de rendement. La méthode optimale proposée de balayage est appliquée à un microscope expérimental de perçage d'un tunnel de balayage ; la simulation et les résultats expérimentaux sont présentés pour illustrer l'efficacité de l'approche proposée pour concevoir la trajectoire optimale de balayage. En ligne : hperez@upbbga.edu.co, qzouatuw@u.washington.edu, devasia@u.washington.edu

A new approach to scan-trajectory design and track: AFM force measurement example / Kyong-Soo Kim in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 130 N°5 (Septembre 2008) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 130 N°5 (Septembre 2008) . - 10 p. Titre : A new approach to scan-trajectory design and track: AFM force measurement example Type de document : texte imprimé Auteurs : Kyong-Soo Kim, Auteur ; Chanmin Su, Auteur ; Qingze, Zou, Auteur Année de publication : 2008 Article en page(s) : 10 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : oscillations;  dynamics  (mechanics);  force;  atomic  force  microscopy;  trajectories  (physics);  design;  errors;  measurement;  algorithms;  simulation;  modeling;  piezoelectric  actuators Résumé : In this article, two practical issues encountered in the design and track of scan trajectories are studied: One issue is the large output oscillations occurring during the scanning, and the other one is the effect of modeling errors on trajectory tracking. Output oscillations need to be small in scanning operations, particularly for lightly damped systems, such as the piezoelectric actuators and the flexible structures. Moreover, modeling errors are ubiquitous in practical applications. The proposed approach extends the recently developed optimal scan-trajectory design and control method by introducing the prefilter design to reduce the output oscillations. Furthermore, a novel enhanced inversion-based iterative control (EIIC) algorithm is proposed. The EIIC algorithm is then integrated with the optimal scan-trajectory design method to compensate for the effect of modeling errors on the scanning. The convergence of the iterative control law is discussed, and the frequency range of the convergence is quantified. The proposed approach is illustrated by implementing it to the high-speed adhesion-force measurements using atomic force microscope. Simulation and experimental work are presented and discussed to demonstrate the efficacy of the proposed approach. The experimental results show that compared to the conventional DC-gain method, the proposed approach can reduce the tracking error by over 25 times during the force-curve measurements. En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] A new approach to scan-trajectory design and track: AFM force measurement example [texte imprimé] / Kyong-Soo Kim, Auteur ; Chanmin Su, Auteur ; Qingze, Zou, Auteur . - 2008 . - 10 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 130 N°5 (Septembre 2008) . - 10 p. Mots-clés : oscillations;  dynamics  (mechanics);  force;  atomic  force  microscopy;  trajectories  (physics);  design;  errors;  measurement;  algorithms;  simulation;  modeling;  piezoelectric  actuators Résumé : In this article, two practical issues encountered in the design and track of scan trajectories are studied: One issue is the large output oscillations occurring during the scanning, and the other one is the effect of modeling errors on trajectory tracking. Output oscillations need to be small in scanning operations, particularly for lightly damped systems, such as the piezoelectric actuators and the flexible structures. Moreover, modeling errors are ubiquitous in practical applications. The proposed approach extends the recently developed optimal scan-trajectory design and control method by introducing the prefilter design to reduce the output oscillations. Furthermore, a novel enhanced inversion-based iterative control (EIIC) algorithm is proposed. The EIIC algorithm is then integrated with the optimal scan-trajectory design method to compensate for the effect of modeling errors on the scanning. The convergence of the iterative control law is discussed, and the frequency range of the convergence is quantified. The proposed approach is illustrated by implementing it to the high-speed adhesion-force measurements using atomic force microscope. Simulation and experimental work are presented and discussed to demonstrate the efficacy of the proposed approach. The experimental results show that compared to the conventional DC-gain method, the proposed approach can reduce the tracking error by over 25 times during the force-curve measurements. En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]