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Modeling piezoresponse force microscopy for low-dimensional material characterization / Amin Salehi-Khojin 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) . - 07 p. Titre : Modeling piezoresponse force microscopy for low-dimensional material characterization : theory and experiment Type de document : texte imprimé Auteurs : Amin Salehi-Khojin, Auteur ; Saeid Bashash, Auteur ; Jalili, Nader, Auteur Année de publication : 2010 Article en page(s) : 07 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : theorems  (mathematics);  force;  electric  potential;  motion;  piezoelectric  materials;  equations  of  motion;  materials  properties;  differential  equations;  modeling;  vibration;  microscopy;  elastic  constants;  frequency;  frequency  response;  parameter  estimation;  stiffness Résumé : Piezoresponse force microscopy (PFM) is an atomic force microscopy-based approach utilized for measuring local properties of piezoelectric materials. The objective of this study is to propose a practical framework for simultaneous estimation of the local stiffness and piezoelectric properties of materials. For this, the governing equation of motion of a vertical PFM is derived at a given point on the sample. Using the expansion theorem, the governing ordinary differential equations of the system and their state-space representation are derived under applied external voltage. For the proof of the concept, the results obtained from both frequency and step responses of a PFM experiment are utilized to simultaneously identify the microcantilever parameters along with local spring constant and piezoelectric coefficient of a periodically poled lithium niobate sample. In this regard, a new parameter estimation strategy is developed for modal identification of system parameters under general frequency response. Results indicate good agreements between the identified model and the experimental data using the proposed modeling and identification framework. This method can be particularly applied for accurate characterization of mechanical and piezoelectric properties of biological species and cells. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/Issue.aspx?issueID=26505&di [...] [article] Modeling piezoresponse force microscopy for low-dimensional material characterization : theory and experiment [texte imprimé] / Amin Salehi-Khojin, Auteur ; Saeid Bashash, Auteur ; Jalili, Nader, Auteur . - 2010 . - 07 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N° 6 (Novembre 2009) . - 07 p. Mots-clés : theorems  (mathematics);  force;  electric  potential;  motion;  piezoelectric  materials;  equations  of  motion;  materials  properties;  differential  equations;  modeling;  vibration;  microscopy;  elastic  constants;  frequency;  frequency  response;  parameter  estimation;  stiffness Résumé : Piezoresponse force microscopy (PFM) is an atomic force microscopy-based approach utilized for measuring local properties of piezoelectric materials. The objective of this study is to propose a practical framework for simultaneous estimation of the local stiffness and piezoelectric properties of materials. For this, the governing equation of motion of a vertical PFM is derived at a given point on the sample. Using the expansion theorem, the governing ordinary differential equations of the system and their state-space representation are derived under applied external voltage. For the proof of the concept, the results obtained from both frequency and step responses of a PFM experiment are utilized to simultaneously identify the microcantilever parameters along with local spring constant and piezoelectric coefficient of a periodically poled lithium niobate sample. In this regard, a new parameter estimation strategy is developed for modal identification of system parameters under general frequency response. Results indicate good agreements between the identified model and the experimental data using the proposed modeling and identification framework. This method can be particularly applied for accurate characterization of mechanical and piezoelectric properties of biological species and cells. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/Issue.aspx?issueID=26505&di [...]

A polynomial-based linear mapping strategy for feedforward compensation of hysteresis in piezoelectric actuators / Saeid Bashash in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 130 N° 3 (Mai/Juin 2008) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 130 N° 3 (Mai/Juin 2008) . - 10 p. Titre : A polynomial-based linear mapping strategy for feedforward compensation of hysteresis in piezoelectric actuators Type de document : texte imprimé Auteurs : Saeid Bashash, Auteur ; Jalili, Nader, Auteur Année de publication : 2010 Article en page(s) : 10 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : memory-based  properties;  piezoelectric  actuators;  Prandtl–Ishlinskii  hysteresis  operator Résumé : A set of memory-based properties is employed in this paper for modeling multiple-path hysteresis response of piezoelectric actuators. These properties, namely, targeting turning points, curve alignment, and wiping-out effect, are applied in a linear mapping strategy to develop a mathematical framework for modeling the hysteresis phenomenon. More specifically, the locations of turning points are detected and recorded for the prediction of future hysteresis trajectory. An internal trajectory is assumed to follow a multiple-segmented path via a continuous connection of several curves passing through every two consequent turning points. These curves adopt their shapes via a linear mapping strategy from the reference hysteresis curves with polynomial configurations. Experimental implementation of the proposed method demonstrates slight improvement over the widely used Prandtl–Ishlinskii hysteresis operator. However, to maintain the level of precision during the operation, a sufficient number of memory units must be included to record the turning points. Otherwise, in the event of memory saturation, two memory-allocation modes, namely, “open” and “closed” strategies, can be implemented. It is shown that the closed memory-allocation strategy demonstrates better performance by keeping the most important target points. The proposed modeling framework is adopted in an inverse model-based control scheme for feedforward compensation of hysteresis nonlinearity. The controller is experimentally implemented on a three-dimensional nanopositioning stage for surface topography tracking, a problem typically encountered in scanning probe microscopy applications. En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/Mobile/article.aspx?article [...] [article] A polynomial-based linear mapping strategy for feedforward compensation of hysteresis in piezoelectric actuators [texte imprimé] / Saeid Bashash, Auteur ; Jalili, Nader, Auteur . - 2010 . - 10 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 130 N° 3 (Mai/Juin 2008) . - 10 p. Mots-clés : memory-based  properties;  piezoelectric  actuators;  Prandtl–Ishlinskii  hysteresis  operator Résumé : A set of memory-based properties is employed in this paper for modeling multiple-path hysteresis response of piezoelectric actuators. These properties, namely, targeting turning points, curve alignment, and wiping-out effect, are applied in a linear mapping strategy to develop a mathematical framework for modeling the hysteresis phenomenon. More specifically, the locations of turning points are detected and recorded for the prediction of future hysteresis trajectory. An internal trajectory is assumed to follow a multiple-segmented path via a continuous connection of several curves passing through every two consequent turning points. These curves adopt their shapes via a linear mapping strategy from the reference hysteresis curves with polynomial configurations. Experimental implementation of the proposed method demonstrates slight improvement over the widely used Prandtl–Ishlinskii hysteresis operator. However, to maintain the level of precision during the operation, a sufficient number of memory units must be included to record the turning points. Otherwise, in the event of memory saturation, two memory-allocation modes, namely, “open” and “closed” strategies, can be implemented. It is shown that the closed memory-allocation strategy demonstrates better performance by keeping the most important target points. The proposed modeling framework is adopted in an inverse model-based control scheme for feedforward compensation of hysteresis nonlinearity. The controller is experimentally implemented on a three-dimensional nanopositioning stage for surface topography tracking, a problem typically encountered in scanning probe microscopy applications. En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/Mobile/article.aspx?article [...]