The Experts below are selected from a list of 381 Experts worldwide ranked by ideXlab platform
Hirohisa Tamagawa - One of the best experts on this subject based on the ideXlab platform.
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Dynamic Characteristics of Selemion CMV-Based IPMC Actuators in High Humidity Environment
Journal of Computational Chemistry, 2014Co-Authors: H. Ngetha, Hirohisa Tamagawa, Minoru Sasaki, Satoshi Ito, K. IkedaAbstract:Electrically-induced bending of Selemion IPMC is caused by the charge induced into the IPMC. This induced charge quantity is susceptible to the absolute humidity of environment. There are two types of charges, the charge causing bending and the rest of charge that causes no bending. In the high humidity environments, where absolute humidity is above 10 gm-3, the quantity of charge causing no bending accounts for the large part of whole charge induced into the Selemion IPMC, while quantity of such charge is negligibly small at the absolute humidity of less than 10 gm-3. Estimating the quantity of those two types of charges individually, we successively analyzed the bending stability of Selemion IPMC at the absolute humidity above 10 gm-3. Consequently, we deduced the following conclusions. 1) There exists a large time delay in the current in response to the voltage input, 2) Current is highly dumping, and 3) Bending behavior is marginally stable under the input of any frequency.
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IPMC bending predicted by the circuit and viscoelastic models considering individual influence of Faradaic and non-Faradaic currents on the bending
Sensors and Actuators B: Chemical, 2014Co-Authors: Kota Ikeda, Minoru Sasaki, Hirohisa TamagawaAbstract:Abstract Electrically induced bending behavior of a highly dehydrated Selemion CMV-based IPMC was analyzed theoretically. The experimental observation suggested that even the highly dehydrated IPMC bending was under the influence of not only Faradaic current but also non-Faradaic current. Hence, it was essential to know the Faradaic and non-Faradaic current influences on the IPMC bending separately for predicting the IPMC bending behavior. A circuit model was proposed for deriving the time-dependent behavior of charge, which was caused by both Faradaic and non-Faradaic currents, passing through the IPMC. In the course of derivation of the time dependence of charge, electrical properties of the IPMC such as resistance and capacitance were obtained, and those physical quantities were reasonable from the stand point of physical chemistry. The time dependent charge behaviors obtained by employing the circuit model successfully resulted in the prediction of bending behavior of the IPMC. The electric properties obtained by the analysis of circuit model was combined with a viscoelastic model we proposed for predicting the bending behavior of IPMC, and the newly proposed viscoelastic model successfully reproduced the experimentally observed behavior of Selemion CMV-based IPMC bending.
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Self-Sensing Control of Nafion-Based Ionic Polymer-Metal Composite (IPMC) Actuator in the Extremely Low Humidity Environment
Actuators, 2013Co-Authors: Minoru Sasaki, Hirohisa Tamagawa, Satoshi Ito, Wenyi Lin, Keiko KikuchiAbstract:This paper presents feedforward, feedback and two-degree-of-freedom control applied to an Ionic Polymer-Metal Composite (IPMC) actuator. It presents a high potential for development of miniature robots and biomedical devices and artificial muscles. We have reported in the last few years that dehydration treatment improves the electrical controllability of bending in Selemion CMV-based IPMCs. We tried to replicate this controllability in Nafion-based IPMC. We found that the displacement of a Nafion-based IPMC was proportional to the total charge imposed, just as in the Selemion-CMV case. This property is the basis of self-sensing controllers for Nafion-based IPMC bending behavior: we perform bending curvature experiments on Nafion-based IPMCs, obtaining the actuator's dynamics and transfer function. From these, we implemented self-sensing controllers using feedforward, feedback and two-degree-of-freedom techniques. All three controllers performed very well with the Nafion-based IPMC actuator.
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Ionic Polymer–Metal Composite of Thermo-Responsive Selemion AMV Coated with Gold Foils
Advanced Robotics, 2012Co-Authors: Hirohisa Tamagawa, Keiko Kikuchi, Kenta Takagi, Minoru SasakiAbstract:Highly dehydrated gold foil-coated Selemion AMV exhibited large bending under electrical stimulation. It bore a relatively well-controllable bending characteristic by the control of electrical stimulation. Conventional ionic polymer–metal composite bending mechanisms could not explain its bending behavior. We speculated that Joule heat played a central role in the bending induction. Employing the classical lamination theory, the influence of Joule heat on its bending behavior was theoretically investigated. The results calculated roughly agreed with the experimental results. Hence, we concluded that the Joule heat was the primary cause of bending induction.
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ionic polymer metal composite of thermo responsive Selemion amv coated with gold foils
Advanced Robotics, 2012Co-Authors: Hirohisa Tamagawa, Keiko Kikuchi, Kenta Takagi, Minoru SasakiAbstract:Highly dehydrated gold foil-coated Selemion AMV exhibited large bending under electrical stimulation. It bore a relatively well-controllable bending characteristic by the control of electrical stimulation. Conventional ionic polymer–metal composite bending mechanisms could not explain its bending behavior. We speculated that Joule heat played a central role in the bending induction. Employing the classical lamination theory, the influence of Joule heat on its bending behavior was theoretically investigated. The results calculated roughly agreed with the experimental results. Hence, we concluded that the Joule heat was the primary cause of bending induction.
Claude Gavach - One of the best experts on this subject based on the ideXlab platform.
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recovery of spent acid by electrodialysis in the zinc hydrometallurgy industry performance study of different cation exchange membranes
Hydrometallurgy, 1997Co-Authors: Mario Boucher, Gérald Pourcelly, Roger Sandeaux, Nancy Turcotte, Virginie Guillemette, Gaetan Lantagne, Agnes Chapotot, Claude GavachAbstract:Abstract A performance study of four different cation-exchange membranes was conducted on laboratory and pilot scale (172 cm 2 /membrane, model CS-0 from Asahi Glass Co.) electrodialysis cells, using Neosepta CMS from Tokuyama Soda Co.; Morgane CRA from Solvay; Selemion CHV from Asahi Glass Co. and Nafion 117 from DuPont, coupled with a Morgane ARA 17-10 anion-exchange membrane. Comparisons were made of the sulphuric acid recovery rate, water transport, metal leakage and energy intake for these membranes. Proton permselectivity and metal leakage, co- and counter-ion transport numbers of the CMS membrane were investigated using Hittorf's method and radiotracer methods. This study shows that electrodialysis is suitable for the treatment of zinc hydrometallurgy effluents. However, R & D work must still be done in order to improve and optimize the technology for its use in future industrial applications. In particular, research efforts must concentrate on the synthesis of affordable and stable cation-exchange membranes showing high selectivity towards protons.
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treatment of uranium leach solution by electrodialysis for anion impurities removal
Hydrometallurgy, 1997Co-Authors: Azzedine Lounis, Claude GavachAbstract:Abstract The purpose of this paper is to determine whether electrodialysis (ED) is suitable for removing molybdenum, carbonate and bicarbonate ions from leach solutions containing uranium. Four different anion exchange membranes were used for the operation: AMV Selemion, A229 Morgane, RAI 5035 and AR 204 UZL 412 Ionics. The results obtained can be considered as providing a basis for developing an electrodialysis process of separation between uranium and molybdenum.
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Influence of the nature of cation on water splitting at the interface of a cation exchange membrane during electrodialysis
Journal de Chimie Physique, 1996Co-Authors: M. Taky, Gérald Pourcelly, A Elmidaoui, Claude GavachAbstract:Le phenomene de la dissociation de l'eau a l'interface d'une membrane echangeuse de cations Selemion CMV au contact de solutions de cations monovalent, bivalent et trivalent est etudie. Les techniques d'investigation sont l'enregistrement des reponses courant-potentiel, la mesure des nombres de transport et des variations de pH. La nature du cation et principalement son caractere acide expliquent la difference de comportement de la membrane CMV au contact des differentes solutions.
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transport properties of electrodialysis membranes in the presence of arginine ii competition between the electrotransport of organic and inorganic ions through a cation exchange membrane in an aqueous solution of arginine chlorhydrate and sodium chlo
Journal of Membrane Science, 1994Co-Authors: Asmaa Fares, Jacqueline Sandeaux, Roger Sandeaux, Claude GavachAbstract:Abstract Electrotransport of ionic species, organic and inorganic, were examined for the same system as in the first part of this study. The CMV Selemion membrane was in contact with an aqueous solution containing both sodium chloride and arginine chlorhydrate. The concentrations ranged from 10 −3 to 10 −1 M and the pH was maintained at pH 7, that is, here the arginine molecule bears a positive charge. Using radiotracers, it was possible to measure the individual fluxes of sodium and arginine counter-ions and also those ofchloride co-ions crossing the membrane under a constant electric current. The experimental results were analysed taking into consideration the kinetics of ion transport. The transport numbers of each ion through the membrane, the ionic concentration in the boundary layer and the rate constant of ion transfer at the membrane–solution interface could be determined and allowed to explain the loss of permselectivity of the ion-exchange membrane in the presence of organic ions.
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Transport properties of electrodialysis membranes in the presence of arginine I. Equilibrium properties of a cation exchange membrane in an aqueous solution of arginine chlorhydrate and sodium chloride
Journal of Membrane Science, 1994Co-Authors: Jacqueline Sandeaux, Asmaa Fares, Roger Sandeaux, Claude GavachAbstract:Abstract Arginine is an amino acid which bears a positive electrical charge at neutral pH. We studied the equilibrium properties of a cation exchange membrane widely used in electrodialysis, the CMV Selemion membrane in contact with aqueous solutions containing both sodium chloride and arginine chlorhydrate. The water content of the membrane, the amount of each ionic species present in the membrane and the individual mobilities of sodium and arginine ions in the membrane were determined as a function of the arginine concentration (10−3 to 10−1M) in the external aqueous solution. The last parameter was obtained by combining the electric resistance and self-diffusion flux measurements. The mobility of the sodium ion was lowered by the presence of arginine inside the membrane material. This result was analysed taking into consideration the variation of the water content in the membrane containing the amino acid.
Sung-hwa Lin - One of the best experts on this subject based on the ideXlab platform.
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in situ measuring osmosis effect of Selemion cmv asv module during ed process of concentrated brine from dsw
Desalination, 2011Co-Authors: Chih-shan Lin, Shih-chi Lee, Jyh-ping Hsu, Shiojenn Tseng, Sung-hwa LinAbstract:Continuing our previous work, in which we analyzed the performance of Selemion ASV membrane (Asahi Glass Engineering) used to reduce the content of sulfate ions in concentrated brine from deep sea water (DSW) via a laboratory-scale electrodialysis (ED) apparatus, we analyze in situ the osmosis effect for Selemion CMV/ASV module (Asahi Glass Engineering) during ED process in this work. By recording the liquid volume in both concentrate and dilute tanks, it is found possible that the water flow across the membranes due to the osmosis effect could be estimated through the measurement of ionic volume flow. The analysis reveals that, when a higher DC voltage is applied, water flows from the concentrate to the dilute at initial stage of ED process, and it flows reversely at later stage; however if a lower DC voltage is applied, water flows from the concentrate to the dilute during whole ED process. Via a carpet searching process, a reasonable effective dynamic hydration number for hydrated ions is found as 3.5, and the water permeability of CMV/ASV module is estimated as 0.25214 cm/h.
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In situ measuring osmosis effect of Selemion CMV/ASV module during ED process of concentrated brine from DSW
Desalination, 2011Co-Authors: Chih-shan Lin, Shih-chi Lee, Jyh-ping Hsu, Shiojenn Tseng, Sung-hwa LinAbstract:Continuing our previous work, in which we analyzed the performance of Selemion ASV membrane (Asahi Glass Engineering) used to reduce the content of sulfate ions in concentrated brine from deep sea water (DSW) via a laboratory-scale electrodialysis (ED) apparatus, we analyze in situ the osmosis effect for Selemion CMV/ASV module (Asahi Glass Engineering) during ED process in this work. By recording the liquid volume in both concentrate and dilute tanks, it is found possible that the water flow across the membranes due to the osmosis effect could be estimated through the measurement of ionic volume flow. The analysis reveals that, when a higher DC voltage is applied, water flows from the concentrate to the dilute at initial stage of ED process, and it flows reversely at later stage; however if a lower DC voltage is applied, water flows from the concentrate to the dilute during whole ED process. Via a carpet searching process, a reasonable effective dynamic hydration number for hydrated ions is found as 3.5, and the water permeability of CMV/ASV module is estimated as 0.25214 cm/h.
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In situ measuring osmosis effect of Selemion CMV/ASV module during ED process of concentrated brine from DSW
Desalination, 2011Co-Authors: Chih-shan Lin, Shih-chi Lee, Jyh-ping Hsu, Shiojenn Tseng, Sung-hwa LinAbstract:[[abstract]]Continuing our previous work, in which we analyzed the performance of Selemion ASV membrane (Asahi Glass Engineering) used to reduce the content of sulfate ions in concentrated brine from deep sea water (DSW) via a laboratory-scale electrodialysis (ED) apparatus, we analyze in situ the osmosis effect for Selemion CMV/ASV module (Asahi Glass Engineering) during ED process in this work. By recording the liquid volume in both concentrate and dilute tanks, it is found possible that the water flow across the membranes due to the osmosis effect could be estimated through the measurement of ionic volume flow. The analysis reveals that, when a higher DC voltage is applied, water flows from the concentrate to the dilute at initial stage of ED process, and it flows reversely at later stage; however if a lower DC voltage is applied, water flows from the concentrate to the dilute during whole ED process. Via a carpet searching process, a reasonable effective dynamic hydration number for hydrated ions is found as 3.5, and the water permeability of CMV/ASV module is estimated as 0.25214 cm/h.[[notice]]補正完畢[[incitationindex]]SCI[[cooperationtype]]國
Fumio Nogata - One of the best experts on this subject based on the ideXlab platform.
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Charge and water in need for the precise control of Selemion bending
Sensors and Actuators B: Chemical, 2007Co-Authors: Hirohisa Tamagawa, Fumio NogataAbstract:Abstract Curvature of Selemion, C, exhibited a quite definite relationship to the charge, Q. There was an almost perfect linear relationship between them, as long as the applied voltage to Selemion was higher than Vth, which was a threshold voltage in need for the induction of redox reaction 2Ag + 1 2 O2 ↔ Ag2O. At Vth or above, a larger quantity of charge was given to the Selemion owing to the reaction. Although such a linear relationship slightly worsened, once the voltage polarity was reversed, Q versus C still maintained a certain definite relationship. Therefore, it was speculated that the Selemion bending curvature was still controllable through the control of charge (or current). Besides charge (or current), the existence of water inside Selemion was an essential factor for the induction of its bending. Because Selemion is an electrically insulating material, quite indifferently to the applied voltage, and the water contained in Selemion created ions, and Selemion must have been converted into a semi-conductive material that could respond to the applied voltage.
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Charge quantity as a sole factor quantitatively governing curvature of Selemion
Sensors and Actuators B: Chemical, 2007Co-Authors: Hirohisa Tamagawa, Fumio Nogata, Minoru SasakiAbstract:It was reported previously that the curvature of largely dehydrated silver-plated Selemion had a quantitatively direct correlation to the charge given to it, as long as the redox reaction of silver layers was induced. It was interpreted such that the control of charge quantity given to Selemion led to the precise control of its bending curvature, which was a quite preferable characteristic for the actuator. On the other hand, it was found previously that the curvature of Selemion was largely influenced by the environmental humidity. Therefore, such a quantitative correlation between the charge quantity and curvature might change once the environmental humidity changes. This paper discusses the limits of validity of this correlation. We derived a conclusion that the Selemion curvature was solely governed by the charge quantity, despite the occurrence of significant alteration of Selemion's electric property in accordance with environmental humidity change. Based on this conclusion, we further proposed a mathematical model which related the charge quantity with the Selemion bending curvature.
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atomic structural change of silver plating layers on the surfaces of Selemion resulting in its excellent bending controllability
Sensors and Actuators B-chemical, 2006Co-Authors: Hirohisa Tamagawa, Fumio NogataAbstract:Abstract One of the ion-exchange polymer membranes called Selemion, containing –SO3H groups in the largely dehydrated state, where its top and bottom surfaces are plated with silver, exhibits an excellent bending controllability for fairly a long while by the applied voltage control unlike the conventionally well-investigated hydrated ion-exchange polymer membranes, such as Nafion. The exact mechanism of such an excellent bending controllability of Selemion has not been elucidated yet. However, the involvement of silver redox reaction in this excellent bending controllability was strongly suggested before. XRD measurement in this study clearly suggests the occurrence of redox reaction, 4Ag + O2 = 2Ag2O. By the bending controllability testing and the current measurements along with this XRD measurement on Selemion and Nafion, we reached the conclusion that the atomic structural change of Ag and Ag2O on the top and bottom surfaces of Selemion caused by the redox reaction is responsible for the excellent Selemion bending controllability. This bending mechanism is totally different from the conventionally accepted mechanism for the bending of hydrated ion-exchange polymer membranes, which cannot exhibit a good bending controllability even for a short while.
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Contribution of Charge to The Control of Selemion Bending
2006 IEEE Conference on Robotics Automation and Mechatronics, 2006Co-Authors: Hirohisa Tamagawa, Fumio NogataAbstract:One of ion exchange polymer membranes (IEPM's) called Selemion (Asahi glass, Co. Ltd., Japan) exhibits a large bending upon an applied voltage. Previously, Selemion curvature was found to have an intimate correlation with charge given to it. This study suggests that the charge created by the occurrence of redox reaction of silver layers on Selemion surfaces brings about such a intimate correlation between charge and curvature. It can be interpreted as the curvature can be precisely controlled with the control of charge (or current).
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Dominant factor for the precise bending control of Selemion
Sensors and Actuators B: Chemical, 2006Co-Authors: Hirohisa Tamagawa, Fumio NogataAbstract:Abstract Not long before, the bending of silver plated Selemion – one of ion exchange polymer membranes (IEPMs) – in the largely dehydrated state was found to be controllable quite precisely through the control of applied voltage even for hours unlike a largely hydrated one, despite the wide belief that the hydration treatment to IEPM is essential for the electrical induction of its bending. Although the current flowing through the Selemion could not be well associated with its bending curvature, we found that the predominant factor for such a precisely controllable bending was attributed to the total charge given to it. Furthermore, it was found to have a predominant effect even on the force Selemion could generate.
Minoru Sasaki - One of the best experts on this subject based on the ideXlab platform.
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Dynamic Characteristics of Selemion CMV-Based IPMC Actuators in High Humidity Environment
Journal of Computational Chemistry, 2014Co-Authors: H. Ngetha, Hirohisa Tamagawa, Minoru Sasaki, Satoshi Ito, K. IkedaAbstract:Electrically-induced bending of Selemion IPMC is caused by the charge induced into the IPMC. This induced charge quantity is susceptible to the absolute humidity of environment. There are two types of charges, the charge causing bending and the rest of charge that causes no bending. In the high humidity environments, where absolute humidity is above 10 gm-3, the quantity of charge causing no bending accounts for the large part of whole charge induced into the Selemion IPMC, while quantity of such charge is negligibly small at the absolute humidity of less than 10 gm-3. Estimating the quantity of those two types of charges individually, we successively analyzed the bending stability of Selemion IPMC at the absolute humidity above 10 gm-3. Consequently, we deduced the following conclusions. 1) There exists a large time delay in the current in response to the voltage input, 2) Current is highly dumping, and 3) Bending behavior is marginally stable under the input of any frequency.
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IPMC bending predicted by the circuit and viscoelastic models considering individual influence of Faradaic and non-Faradaic currents on the bending
Sensors and Actuators B: Chemical, 2014Co-Authors: Kota Ikeda, Minoru Sasaki, Hirohisa TamagawaAbstract:Abstract Electrically induced bending behavior of a highly dehydrated Selemion CMV-based IPMC was analyzed theoretically. The experimental observation suggested that even the highly dehydrated IPMC bending was under the influence of not only Faradaic current but also non-Faradaic current. Hence, it was essential to know the Faradaic and non-Faradaic current influences on the IPMC bending separately for predicting the IPMC bending behavior. A circuit model was proposed for deriving the time-dependent behavior of charge, which was caused by both Faradaic and non-Faradaic currents, passing through the IPMC. In the course of derivation of the time dependence of charge, electrical properties of the IPMC such as resistance and capacitance were obtained, and those physical quantities were reasonable from the stand point of physical chemistry. The time dependent charge behaviors obtained by employing the circuit model successfully resulted in the prediction of bending behavior of the IPMC. The electric properties obtained by the analysis of circuit model was combined with a viscoelastic model we proposed for predicting the bending behavior of IPMC, and the newly proposed viscoelastic model successfully reproduced the experimentally observed behavior of Selemion CMV-based IPMC bending.
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Self-Sensing Control of Nafion-Based Ionic Polymer-Metal Composite (IPMC) Actuator in the Extremely Low Humidity Environment
Actuators, 2013Co-Authors: Minoru Sasaki, Hirohisa Tamagawa, Satoshi Ito, Wenyi Lin, Keiko KikuchiAbstract:This paper presents feedforward, feedback and two-degree-of-freedom control applied to an Ionic Polymer-Metal Composite (IPMC) actuator. It presents a high potential for development of miniature robots and biomedical devices and artificial muscles. We have reported in the last few years that dehydration treatment improves the electrical controllability of bending in Selemion CMV-based IPMCs. We tried to replicate this controllability in Nafion-based IPMC. We found that the displacement of a Nafion-based IPMC was proportional to the total charge imposed, just as in the Selemion-CMV case. This property is the basis of self-sensing controllers for Nafion-based IPMC bending behavior: we perform bending curvature experiments on Nafion-based IPMCs, obtaining the actuator's dynamics and transfer function. From these, we implemented self-sensing controllers using feedforward, feedback and two-degree-of-freedom techniques. All three controllers performed very well with the Nafion-based IPMC actuator.
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Ionic Polymer–Metal Composite of Thermo-Responsive Selemion AMV Coated with Gold Foils
Advanced Robotics, 2012Co-Authors: Hirohisa Tamagawa, Keiko Kikuchi, Kenta Takagi, Minoru SasakiAbstract:Highly dehydrated gold foil-coated Selemion AMV exhibited large bending under electrical stimulation. It bore a relatively well-controllable bending characteristic by the control of electrical stimulation. Conventional ionic polymer–metal composite bending mechanisms could not explain its bending behavior. We speculated that Joule heat played a central role in the bending induction. Employing the classical lamination theory, the influence of Joule heat on its bending behavior was theoretically investigated. The results calculated roughly agreed with the experimental results. Hence, we concluded that the Joule heat was the primary cause of bending induction.
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ionic polymer metal composite of thermo responsive Selemion amv coated with gold foils
Advanced Robotics, 2012Co-Authors: Hirohisa Tamagawa, Keiko Kikuchi, Kenta Takagi, Minoru SasakiAbstract:Highly dehydrated gold foil-coated Selemion AMV exhibited large bending under electrical stimulation. It bore a relatively well-controllable bending characteristic by the control of electrical stimulation. Conventional ionic polymer–metal composite bending mechanisms could not explain its bending behavior. We speculated that Joule heat played a central role in the bending induction. Employing the classical lamination theory, the influence of Joule heat on its bending behavior was theoretically investigated. The results calculated roughly agreed with the experimental results. Hence, we concluded that the Joule heat was the primary cause of bending induction.