Abstract
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.
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Project supported by the the National Natural Science Foundation of China (No. 51775485)
Dr. Tao LIU, corresponding author of this invited review article, received M. Eng. degree in mechanical engineering from the Harbin Institute of Technology, Harbin, China, in 2003 and Ph. D. in engineering from Kochi University of Technology, Kochi, Japan, in 2006. He was an assistant professor in the Department of Intelligent Mechanical Systems Engineering, Kochi University of Technology, Japan, from 2009 to 2013. He is currently a professor at the State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, China, and Director of Institute of Micro-/Nanotechnology and Precision Engineering in the Department of Mechanical Engineering, Zhejiang University, China. His current research interests include wearable sensor systems, rehabilitation robots, biomechanics, and human motion analysis.
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Dong, Ty., Zhang, Xl. & Liu, T. Artificial muscles for wearable assistance and rehabilitation. Frontiers Inf Technol Electronic Eng 19, 1303–1315 (2018). https://doi.org/10.1631/FITEE.1800618
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DOI: https://doi.org/10.1631/FITEE.1800618
Key words
- Artificial muscle
- Smart material
- Dielectric elastomers (DE)
- Polyvinyl chloride (PVC) gel
- Actuator
- Wearable assistance
- Rehabilitation