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Sliding mode control of mechanical systems actuated by shape memory alloy / Hashem Ashrafiuon in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°1 (Janvier/Février 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 06 p. Titre : Sliding mode control of mechanical systems actuated by shape memory alloy Type de document : texte imprimé Auteurs : Hashem Ashrafiuon, Auteur ; Vijay Reddy Jala, Auteur Année de publication : 2009 Article en page(s) : 06 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : temperature;  phase  transitions;  cooling;  control  equipment;  robots;  wire;  shape  memory  alloys;  stress;  equations  of  motion;  sliding  mode  control;  actuators;  convection;  modeling;  equations;  Kalman  filters;  position  control;  heating Résumé : This paper presents a model-based sliding mode control law for mechanical systems, which use shape memory alloys (SMAs) as actuators. The systems under consideration are assumed to be fully actuated and represented by unconstrained equations of motion. A system model is developed by combining the equations of motion with SMA heat convection, constitutive law, and phase transformation equations, which account for hysteresis. The control law is introduced using asymptotically stable second-order sliding surfaces. Robustness is guaranteed through the inclusion of modeling uncertainties in the controller development. The control law is developed assuming only positions are available for measurement. The unmeasured states, which include velocities and SMA temperatures and stresses, are estimated using an extended Kalman filter based on the nonlinear system model. The control law is applied to a three-link planar robot for position control problem. Simulation and experimental results show good agreement and verify the robustness of the control law despite significant modeling uncertainty. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...] [article] Sliding mode control of mechanical systems actuated by shape memory alloy [texte imprimé] / Hashem Ashrafiuon, Auteur ; Vijay Reddy Jala, Auteur . - 2009 . - 06 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°1 (Janvier/Février 2009) . - 06 p. Mots-clés : temperature;  phase  transitions;  cooling;  control  equipment;  robots;  wire;  shape  memory  alloys;  stress;  equations  of  motion;  sliding  mode  control;  actuators;  convection;  modeling;  equations;  Kalman  filters;  position  control;  heating Résumé : This paper presents a model-based sliding mode control law for mechanical systems, which use shape memory alloys (SMAs) as actuators. The systems under consideration are assumed to be fully actuated and represented by unconstrained equations of motion. A system model is developed by combining the equations of motion with SMA heat convection, constitutive law, and phase transformation equations, which account for hysteresis. The control law is introduced using asymptotically stable second-order sliding surfaces. Robustness is guaranteed through the inclusion of modeling uncertainties in the controller development. The control law is developed assuming only positions are available for measurement. The unmeasured states, which include velocities and SMA temperatures and stresses, are estimated using an extended Kalman filter based on the nonlinear system model. The control law is applied to a three-link planar robot for position control problem. Simulation and experimental results show good agreement and verify the robustness of the control law despite significant modeling uncertainty. DEWEY : 629.8 ISSN : 0022-0434 En ligne : dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&issueid=2 [...]