Dielectric elastomers(DEs)show complex mechanical behaviors with different boundary conditions,geometry sizes,and prestress.In this study,a three-component linear visco-hyperelastic model of DE film is developed based...Dielectric elastomers(DEs)show complex mechanical behaviors with different boundary conditions,geometry sizes,and prestress.In this study,a three-component linear visco-hyperelastic model of DE film is developed based on equibiaxial tension.By applying hereditary integrals to analyze multiple-segment loading processesof film stretching,the model parameters are extracted by fitting the visco-hyperelastic film model to the experimental data.To demonstrate the performance of proposed model,the obtained predictive results are compared with the experimental results under different equibiaxial loading conditions.The good agreement between them shows that the linear visco-hyperelastic model is a promising tool for analytically investigating the property of pre-stretched DE actuators.Finally,the Prony series coefficients are calculated according to the relaxation function.This is helpful for simulation analysis using commercial finite element software.展开更多
Traditional exoskeletons have made considerable contributions to people in terms of providing wearable assistance and rehabilitation. However, exoskeletons still have some disadvantages, such as being heavy, bulky, st...Traditional exoskeletons have made considerable contributions to people in terms of providing wearable assistance and rehabilitation. However, exoskeletons still have some disadvantages, such as being heavy, bulky, stiff, noisy, and having a fixed center of rotation that can be a burden on elders and patients with weakened muscles. Conversely, artificial muscles based on soft, smart materials possess the attributes of being lightweight, compact, highly flexible, and have mute actuation, for which they are considered to be the most similar to natural muscles. Among these materials, dielectric elastomer(DE) and polyvinyl chloride(PVC) gel exhibit considerable actuation strain, high actuation stress, high response speed, and long life span, which give them great potential for application in wearable assistance and rehabilitation. Unfortunately, there is very little research on the application of these two materials in these fields. In this review, we first introduce the working principles of the DE and PVC gel separately. Next, we summarize the DE materials and the preparation of PVC gel. Then, we review the electrodes and self-sensing systems of the two materials. Lastly, we present the initial applications of these two materials for wearable assistance and rehabilitation.展开更多
基金supported by the Natural Science Fund for colleges and universities in Jiangsu Province (No.18KJB530012)Advanced Study of Professional Leaders in Higher Vocational College of Jiangsu Province (No.2019GRGDYX113)+2 种基金National Key Research and Development Program (No.2017YFB1300600)the Middle-aged & Young key teachers of Colleges and Universities of Jiangsu Province (Grant:2016-15)PhD Foundation of Nanjing Institute of Information Technology (No.YB20160201)
文摘Dielectric elastomers(DEs)show complex mechanical behaviors with different boundary conditions,geometry sizes,and prestress.In this study,a three-component linear visco-hyperelastic model of DE film is developed based on equibiaxial tension.By applying hereditary integrals to analyze multiple-segment loading processesof film stretching,the model parameters are extracted by fitting the visco-hyperelastic film model to the experimental data.To demonstrate the performance of proposed model,the obtained predictive results are compared with the experimental results under different equibiaxial loading conditions.The good agreement between them shows that the linear visco-hyperelastic model is a promising tool for analytically investigating the property of pre-stretched DE actuators.Finally,the Prony series coefficients are calculated according to the relaxation function.This is helpful for simulation analysis using commercial finite element software.
基金supported by the the National Natural Science Foundation of China(No.51775485)
文摘Traditional exoskeletons have made considerable contributions to people in terms of providing wearable assistance and rehabilitation. However, exoskeletons still have some disadvantages, such as being heavy, bulky, stiff, noisy, and having a fixed center of rotation that can be a burden on elders and patients with weakened muscles. Conversely, artificial muscles based on soft, smart materials possess the attributes of being lightweight, compact, highly flexible, and have mute actuation, for which they are considered to be the most similar to natural muscles. Among these materials, dielectric elastomer(DE) and polyvinyl chloride(PVC) gel exhibit considerable actuation strain, high actuation stress, high response speed, and long life span, which give them great potential for application in wearable assistance and rehabilitation. Unfortunately, there is very little research on the application of these two materials in these fields. In this review, we first introduce the working principles of the DE and PVC gel separately. Next, we summarize the DE materials and the preparation of PVC gel. Then, we review the electrodes and self-sensing systems of the two materials. Lastly, we present the initial applications of these two materials for wearable assistance and rehabilitation.