Electroactive Polymer Actuators and Devices (EAPAD) XXII最新文献

{"title":"Influence of the electrode on the actuation of thin-film DE transducers","authors":"A. Masoud, Timm Krueger, J. Maas","doi":"10.1117/12.2559096","DOIUrl":"https://doi.org/10.1117/12.2559096","url":null,"abstract":"In this contribution, an analytical modeling approach to describe the influence of electrodes on the actuation behaviour of DE-transducers is presented and validated by corresponding FE-simulations. As the impact of electrodes has almost been neglected in previous work, our theoretical approach considers the electrode’s dimensions and stiffness with respect to quantities of the elastomeric poly- mer film covered by the electrodes. The analytical modeling is based on energy considerations utilizing hyperelastic models for both, the polymer film and the compliant electrodes and by bal- ancing forces in each direction. The corresponding FE-analysis performed in COMSOL multiphysics validate the analytically obtained results. It turned out that area, thickness and stiffness of the electrodes regarding to the polymer’s quantities have a strong impact of the actuation behaviour of DE-transducers. Obtained results are reflected by published measurements validating our findings.","PeriodicalId":341018,"journal":{"name":"Electroactive Polymer Actuators and Devices (EAPAD) XXII","volume":"127 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132931260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inkjet printing and characterization of applied electrodes for dielectric elastomer transducer","authors":"Ozan Çabuk, M. Wegener, B. Gruber, S. Seidel, J. Maas","doi":"10.1117/12.2558545","DOIUrl":"https://doi.org/10.1117/12.2558545","url":null,"abstract":"Dielectric elastomer (DE) transducers consist of a dielectric elastomer layer coated with flexible electrodes on both surfaces. Apart from the dielectric film, the properties of the electrodes affect the electromechanical behavior of the DEtransducers as well. Electrodes must be able to sustain conductivity at large deformations, must exhibit a low stiffness and provide sufficient adhesion to the DE-layer. Different processing technologies exist for application of electrodes suitable for DE-transducer. Among them, the inkjet printing technique gained attention in recent years as a very precise and purely non-contact deposition method to fabricate thin electrode layers. In contrast to other methods, e. g. using a shadow mask in case of spraying, the inkjet technique is very versatile and allows a fast adjustment of the processed electrode geometry. In order to describe the requirements of the inkjet printing process and ink adaptation itself, we present a theoretical description of those processes accompanied with the definition of parameters, which need to be considered during experimental processing. Furthermore, we present first results of our adaptation of an ink formulation and an inkjet printing procedure. For this purpose a commercial electrode paste, Elastosil LR 3162, made of carbon black-silicone composite, was adapted to the inkjet printing process. In first experimental studies, the adapted ink was inkjet printed onto dielectric elastomer layers by varying the inkjet printing parameters. Different measurements were performed in order to characterize separate dots as well as continuous lines and areas of the inkjet printed electrodes. The electrode thicknesses and its shapes were recorded by surface-profile measurements. The electrical properties of the printed electrodes as well as their mechanical influence on the elastic properties of the elastomer layers were measured under continuous and cyclic mechanical stretching.","PeriodicalId":341018,"journal":{"name":"Electroactive Polymer Actuators and Devices (EAPAD) XXII","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134463063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An automatically rainproofing bike helmet through light-sensitive hydrogel meshes: design, modeling and experiments","authors":"Adrian Ehrenhofer, A. Mieting, Sascha Pfeil, J. Mersch, C. Cherif, G. Gerlach, T. Wallmersperger","doi":"10.1117/12.2557728","DOIUrl":"https://doi.org/10.1117/12.2557728","url":null,"abstract":"For everyday cycling, one needs to carry rainproof clothing just for the case of unexpected downpours. In the present research, we present a concept for a helmet which is automatically rainproof when the rain starts. When the sun comes out, the helmet is breathable again even before it completely dries up. This functionality is provided by active hydrogel meshes. Hydrogel meshes offer great advantages due to their ability to change the aperture size with swelling and deswelling. In our current work, we present the design and modeling steps for hydrogel-layered active meshes which use (i) swelling and deswelling in hydrated state and (ii) swelling starting from the dry state. The main goal is to close the air openings of a bicycle helmet when rain starts as an automatic rainproofing. This can be achieved through the swelling of the hydrogel pNiPAAM-co-chlorophyllin in the meshes, which leads to closing when hydrated. At the same time, the light-sensitive behavior leads to opening of the apertures under direct sun exposure, i.e. when the sun appears again after the rain. We present the steps of modeling and design using the Normalized Extended Temperature-Expansion-Model (NETEM) to perform simulations in Abaqus. The model is capable of describing both the swelling of the hydrogel under light stimulus and the volume change due to hydration. It is based on the analogy between free swelling and thermal expansion and defined for nonlinear displacements. We also discuss the fabrication process of hydrogel-layered fibers and challenges in their application and simulation. As a proof of concept for hydrogel-layered meshes, we show preliminary experimental results of a poly(acrylamide)/poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAAm/PAMPS) hydrogel with semi-interpenetrated network (SIPN) structure and its swelling capacities on a mesh. Starting from the active hydrogel meshes as presented in the current work, the next step can be smart textiles that harness the power of hydrogels: the adaptation to combinations of stimuli – like humidity, temperature and brightness - that define environments.","PeriodicalId":341018,"journal":{"name":"Electroactive Polymer Actuators and Devices (EAPAD) XXII","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121702606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}