Shubham Patel, Faheem Ershad, Min Zhao, Roslyn Rivkah Isseroff, Bin Duan, Yubin Zhou, Yong Wang, Cunjiang Yu
Wound healing is one of the most complex processes in the human body, supported by many cellular events that are tightly coordinated to repair the wound efficiently. Chronic wounds have potentially life-threatening consequences. Traditional wound dressings come in direct contact with wounds to help them heal and avoid further complications. However, traditional wound dressings have some limitations. These dressings do not provide real-time information on wound conditions, leading clinicians to miss the best time for adjusting treatment. Moreover, the current diagnosis of wounds is relatively subjective. Wearable electronics have become a unique platform to potentially monitor wound conditions in a continuous manner accurately and even to serve as accelerated healing vehicles. In this review, we briefly discuss the wound status with some objective parameters/biomarkers influencing wound healing, followed by the presentation of various novel wearable devices used for monitoring wounds and accelerating wound healing. We further summarize the associated device working principles. This review concludes by highlighting some major challenges in wearable devices toward wound healing that need to be addressed by the research community.
{"title":"Wearable electronics for skin wound monitoring and healing.","authors":"Shubham Patel, Faheem Ershad, Min Zhao, Roslyn Rivkah Isseroff, Bin Duan, Yubin Zhou, Yong Wang, Cunjiang Yu","doi":"10.20517/ss.2022.13","DOIUrl":"https://doi.org/10.20517/ss.2022.13","url":null,"abstract":"<p><p>Wound healing is one of the most complex processes in the human body, supported by many cellular events that are tightly coordinated to repair the wound efficiently. Chronic wounds have potentially life-threatening consequences. Traditional wound dressings come in direct contact with wounds to help them heal and avoid further complications. However, traditional wound dressings have some limitations. These dressings do not provide real-time information on wound conditions, leading clinicians to miss the best time for adjusting treatment. Moreover, the current diagnosis of wounds is relatively subjective. Wearable electronics have become a unique platform to potentially monitor wound conditions in a continuous manner accurately and even to serve as accelerated healing vehicles. In this review, we briefly discuss the wound status with some objective parameters/biomarkers influencing wound healing, followed by the presentation of various novel wearable devices used for monitoring wounds and accelerating wound healing. We further summarize the associated device working principles. This review concludes by highlighting some major challenges in wearable devices toward wound healing that need to be addressed by the research community.</p>","PeriodicalId":74837,"journal":{"name":"Soft science","volume":"2 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10093663/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9302896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gels, as typical flexible and soft materials, possess the intrinsic merits of transparent bionic structures, superior mechanical properties and excellent elasticity and viscosity. Recently, gel-based materials have attracted significant attention as a result of their broad and promising applications in biomedical, energy storage, light emission, actuator, military and aerospace devices, especially the intelligent sensing for human-related applications. Among the various flexible and soft pressure sensors, gel-based ones have been gradually studied as an emerging hot research topic. This review focuses on the latest findings in the rapidly developing field of gel-based pressure sensors. Firstly, the classification and properties of the three types of gels and their corresponding fabrication methods are introduced. Secondly, the four basic working principles of pressure sensors are summarized with a comparison of their advantages and disadvantages, followed by an introduction to the construction of pressure sensors based on gel structures. Thirdly, the latest representative research on the three types of gel-based materials towards various wearable sensing applications, including electronic skin, human motion capture, healthcare and rehabilitation, physiological activity monitoring and human-machine interactions, is comprehensively reviewed. Finally, a summary of the remaining challenges and an outline of the development trend for this field are presented.
{"title":"Recent advances in flexible and soft gel-based pressure sensors","authors":"Gui-zhen Sun, Peng Wang, Yongxiang Jiang, Hongchang Sun, Chuizhou Meng, Shijie Guo","doi":"10.20517/ss.2022.16","DOIUrl":"https://doi.org/10.20517/ss.2022.16","url":null,"abstract":"Gels, as typical flexible and soft materials, possess the intrinsic merits of transparent bionic structures, superior mechanical properties and excellent elasticity and viscosity. Recently, gel-based materials have attracted significant attention as a result of their broad and promising applications in biomedical, energy storage, light emission, actuator, military and aerospace devices, especially the intelligent sensing for human-related applications. Among the various flexible and soft pressure sensors, gel-based ones have been gradually studied as an emerging hot research topic. This review focuses on the latest findings in the rapidly developing field of gel-based pressure sensors. Firstly, the classification and properties of the three types of gels and their corresponding fabrication methods are introduced. Secondly, the four basic working principles of pressure sensors are summarized with a comparison of their advantages and disadvantages, followed by an introduction to the construction of pressure sensors based on gel structures. Thirdly, the latest representative research on the three types of gel-based materials towards various wearable sensing applications, including electronic skin, human motion capture, healthcare and rehabilitation, physiological activity monitoring and human-machine interactions, is comprehensively reviewed. Finally, a summary of the remaining challenges and an outline of the development trend for this field are presented.","PeriodicalId":74837,"journal":{"name":"Soft science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67660057","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}
Interventional surgery has the advantages of small skin incision, little bleed loss, low postoperative infection and short recovery time, and thus has gradually become the preferred surgical approach over traditional open surgeries. Even though great achievements have been made towards clinical applications, limitations still exist, among which the loss of natural tactile perception of surgeons due to their indirect touch sense along the long catheter to the intervening human tissue is the crucial one. In recent years, researchers have dedicated great efforts in developing advanced medical catheters with smart tactile perception ability and made considerable progress. In this regard, we review the most recent development on the state-of-the-art miniature flexible and soft tactile sensors that are able to be integrated in the tip or on the side wall of medical catheters, with focus on the sensing mechanism, design requirement, device configuration and sensing performance of different types of sensors as well as their application demonstration in synthetic anatomical models and in-vivo animal experiment. After reviewing the representative research work, challenges that still exist are summarized and prospects toward future development are put forward.
{"title":"A brief review on miniature flexible and soft tactile sensors for interventional catheter applications","authors":"Yurui Li, Peng Wang, Chuizhou Meng, Wenqiang Chen, Longyuan Zhang, Shijie Guo","doi":"10.20517/ss.2022.05","DOIUrl":"https://doi.org/10.20517/ss.2022.05","url":null,"abstract":"Interventional surgery has the advantages of small skin incision, little bleed loss, low postoperative infection and short recovery time, and thus has gradually become the preferred surgical approach over traditional open surgeries. Even though great achievements have been made towards clinical applications, limitations still exist, among which the loss of natural tactile perception of surgeons due to their indirect touch sense along the long catheter to the intervening human tissue is the crucial one. In recent years, researchers have dedicated great efforts in developing advanced medical catheters with smart tactile perception ability and made considerable progress. In this regard, we review the most recent development on the state-of-the-art miniature flexible and soft tactile sensors that are able to be integrated in the tip or on the side wall of medical catheters, with focus on the sensing mechanism, design requirement, device configuration and sensing performance of different types of sensors as well as their application demonstration in synthetic anatomical models and in-vivo animal experiment. After reviewing the representative research work, challenges that still exist are summarized and prospects toward future development are put forward.","PeriodicalId":74837,"journal":{"name":"Soft science","volume":"360 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67659593","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}
Self-assembled monolayers (SAMs) have found use in diverse applications that range from corrosion prevention to biosensing. However, for all of these applications, stability remains a key challenge for the utilization of SAMs. Over the last decade, intermolecular crosslinking as a method to enhance the thermal and chemical stability of SAMs has attracted increased attention from scientists and engineers. As such, this review introduces a variety of crosslinked SAMs: (1) aromatic thiol-based SAMs; (2) olefinic- and acetylenic-based alkanethiols; (3) other aliphatic alkanethiols; (4) silane-based alkanethiols; (5) boronic acid-based alkanethiols; and (6) crosslinked SAMs realized by hydrogen bonding. By offering insight into the structure-application relationships of the aforementioned SAMs, this review seeks to inspire researchers toward the development of new classes of SAMs with enhanced stabilities and working lifetimes.
{"title":"Crosslinked organosulfur-based self-assembled monolayers: formation and applications","authors":"Tianlang Yu, Maria D. Marquez, H. Tran, T. Lee","doi":"10.20517/ss.2022.04","DOIUrl":"https://doi.org/10.20517/ss.2022.04","url":null,"abstract":"Self-assembled monolayers (SAMs) have found use in diverse applications that range from corrosion prevention to biosensing. However, for all of these applications, stability remains a key challenge for the utilization of SAMs. Over the last decade, intermolecular crosslinking as a method to enhance the thermal and chemical stability of SAMs has attracted increased attention from scientists and engineers. As such, this review introduces a variety of crosslinked SAMs: (1) aromatic thiol-based SAMs; (2) olefinic- and acetylenic-based alkanethiols; (3) other aliphatic alkanethiols; (4) silane-based alkanethiols; (5) boronic acid-based alkanethiols; and (6) crosslinked SAMs realized by hydrogen bonding. By offering insight into the structure-application relationships of the aforementioned SAMs, this review seeks to inspire researchers toward the development of new classes of SAMs with enhanced stabilities and working lifetimes.","PeriodicalId":74837,"journal":{"name":"Soft science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67659583","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}
Portable flexible electronics based on petroleum-based polymers have stepped onto the stage of modern technology. Increasing environmental problems facilitate emerging technologies based on cellulose because of its abundant sources and the nature of CO2 consumption and biodegradability. Bacterial cellulose (BC) stands out among all cellulose materials because of its unique features, including the abundant hydrogen bonds, small diameter, three-dimensional nano-networked structures, high purity and crystallinity, and the degree of polymerization. The adequate properties impart BC and its nano-nano composites with superior balance among ductility, strength, and porosity, which are crucial for wearables. The principles of this balance, the fabrication of the nano-nano composites, and the wearable electronic applications based on BC are discussed in detail in this review.
{"title":"Flexible, high-strength, and porous nano-nano composites based on bacterial cellulose for wearable electronics: a review","authors":"Fangyi Guan, C. Guo","doi":"10.20517/ss.2021.19","DOIUrl":"https://doi.org/10.20517/ss.2021.19","url":null,"abstract":"Portable flexible electronics based on petroleum-based polymers have stepped onto the stage of modern technology. Increasing environmental problems facilitate emerging technologies based on cellulose because of its abundant sources and the nature of CO2 consumption and biodegradability. Bacterial cellulose (BC) stands out among all cellulose materials because of its unique features, including the abundant hydrogen bonds, small diameter, three-dimensional nano-networked structures, high purity and crystallinity, and the degree of polymerization. The adequate properties impart BC and its nano-nano composites with superior balance among ductility, strength, and porosity, which are crucial for wearables. The principles of this balance, the fabrication of the nano-nano composites, and the wearable electronic applications based on BC are discussed in detail in this review.","PeriodicalId":74837,"journal":{"name":"Soft science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67659958","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}
Soft actuators have been receiving tremendous attention as a result of their excellent adaptability to the environment. However, due to their inherently low stiffness, soft actuators are difficult to adapt to high-load tasks. Despite previous efforts in developing stiffness-tunable actuators by utilizing variable stiffness materials, they still suffer from limitations, including relatively low load and locking capacity to grasp weights and difficulties regarding their fabrication with complex structures. This work reports a novel stiffness-tunable and shape-locking soft (Tri-S) actuator using hybrid multi-material 3D printing. The Tri-S actuator consists of polylactic acid, thermoplastic polyurethane and a flexible carbon fiber heating wire. Its stiffness can be effectively tuned by Joule heating. A soft robotic gripper equipped with three Tri-S actuators demonstrates their stiffness-tunable and shape-locking capability by grasping and holding objects of various shapes and weights. The gripper can grasp weights up to 2.2 kg with an external driving force by tuning the stiffness and hold weights up to 310 g depending on its own shape locking without an external driving power source.
{"title":"Stiffness-tunable and shape-locking soft actuators based on 3D-printed hybrid multi-materials","authors":"","doi":"10.20517/ss.2022.19","DOIUrl":"https://doi.org/10.20517/ss.2022.19","url":null,"abstract":"Soft actuators have been receiving tremendous attention as a result of their excellent adaptability to the environment. However, due to their inherently low stiffness, soft actuators are difficult to adapt to high-load tasks. Despite previous efforts in developing stiffness-tunable actuators by utilizing variable stiffness materials, they still suffer from limitations, including relatively low load and locking capacity to grasp weights and difficulties regarding their fabrication with complex structures. This work reports a novel stiffness-tunable and shape-locking soft (Tri-S) actuator using hybrid multi-material 3D printing. The Tri-S actuator consists of polylactic acid, thermoplastic polyurethane and a flexible carbon fiber heating wire. Its stiffness can be effectively tuned by Joule heating. A soft robotic gripper equipped with three Tri-S actuators demonstrates their stiffness-tunable and shape-locking capability by grasping and holding objects of various shapes and weights. The gripper can grasp weights up to 2.2 kg with an external driving force by tuning the stiffness and hold weights up to 310 g depending on its own shape locking without an external driving power source.","PeriodicalId":74837,"journal":{"name":"Soft science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67660127","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}
Nam-in Kim, Jong Moon Lee, Mina Moradnia, Jie Chen, S. Pouladi, Miad Yarali, Ja Yeon Kim, M. Kwon, T. R. Lee, J. Ryou
Whereas piezoelectric pressure sensors (PPSs) have been applied in the monitoring of human body movement and physiological parameters, they show inherent limitations in wearable applications, including toxicity, degradation, and brittleness. In this study, we develop safe, stable, and mechanically flexible composite thin films consisting of polyvinylidene fluoride (PVDF), BaTiO3 nanoparticles (BTO-NPs), and textured aluminum nitride (AlN) thin film for the demonstration of wearable PPS with enhanced output performance and biocompatibility. The PPS made of BTO-NP-embedded-PVDF and AlN film on Cu foil is attached to different parts of human body to measure different output voltages depending on the physiological and physical stimulus. The simple bending (from breathing, chewing, and swallowing), joint motions (at wrist, elbow, and finger), and low- (from eyeball movement) and high-pressure applications (by squat, lunge, and walking) are measured. Our PVDF+BTO-NP/AlN-PPS (PBA-PPS) device has the potential for personal safety, healthcare, and activity monitoring applications with easy wearability.
{"title":"Biocompatible composite thin-film wearable piezoelectric pressure sensor for monitoring of physiological and muscle motions","authors":"Nam-in Kim, Jong Moon Lee, Mina Moradnia, Jie Chen, S. Pouladi, Miad Yarali, Ja Yeon Kim, M. Kwon, T. R. Lee, J. Ryou","doi":"10.20517/ss.2022.06","DOIUrl":"https://doi.org/10.20517/ss.2022.06","url":null,"abstract":"Whereas piezoelectric pressure sensors (PPSs) have been applied in the monitoring of human body movement and physiological parameters, they show inherent limitations in wearable applications, including toxicity, degradation, and brittleness. In this study, we develop safe, stable, and mechanically flexible composite thin films consisting of polyvinylidene fluoride (PVDF), BaTiO3 nanoparticles (BTO-NPs), and textured aluminum nitride (AlN) thin film for the demonstration of wearable PPS with enhanced output performance and biocompatibility. The PPS made of BTO-NP-embedded-PVDF and AlN film on Cu foil is attached to different parts of human body to measure different output voltages depending on the physiological and physical stimulus. The simple bending (from breathing, chewing, and swallowing), joint motions (at wrist, elbow, and finger), and low- (from eyeball movement) and high-pressure applications (by squat, lunge, and walking) are measured. Our PVDF+BTO-NP/AlN-PPS (PBA-PPS) device has the potential for personal safety, healthcare, and activity monitoring applications with easy wearability.","PeriodicalId":74837,"journal":{"name":"Soft science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67659665","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}
Additive manufacturing is an arising technology for soft materials and structures with improved complexity and functionality, and it has been gradually widespread in fields including soft robotics, flexible electronics and biomedical devices. Along with the development of material systems and fabrication techniques, mechanical design principles for additive manufactured soft materials were greatly developed and evolved over the past few years, and some special issues that are distinct from conventional manufacturing techniques emerged. In this short review, we mainly focus on additive manufactured soft materials that are in great request of mechanical models/simulations to provide design guidelines, therefore, topics such as soft robotics and electronics are out of scope here. We firstly discuss the mechanical designs for controlling shape distortions and interfacial strength, as they are directly related to the quality and reliability of additive manufactured soft materials. Then, design principles and manufacturing strategies for bio-inspired composites, which makes up a large part of current researches on additive manufactured soft materials, are summarized integrally from three aspects. In addition, basic mechanical considerations for additive manufactured 4D shape changing structures are explained, together with the review of recent theories and numerical approaches. Finally, suggestions and perspectives are given for future developments of soft material additive manufacturing.
{"title":"A brief review of mechanical designs for additive manufactured soft materials","authors":"Qiang Zhang, Yan Shi, Zeang Zhao","doi":"10.20517/ss.2021.22","DOIUrl":"https://doi.org/10.20517/ss.2021.22","url":null,"abstract":"Additive manufacturing is an arising technology for soft materials and structures with improved complexity and functionality, and it has been gradually widespread in fields including soft robotics, flexible electronics and biomedical devices. Along with the development of material systems and fabrication techniques, mechanical design principles for additive manufactured soft materials were greatly developed and evolved over the past few years, and some special issues that are distinct from conventional manufacturing techniques emerged. In this short review, we mainly focus on additive manufactured soft materials that are in great request of mechanical models/simulations to provide design guidelines, therefore, topics such as soft robotics and electronics are out of scope here. We firstly discuss the mechanical designs for controlling shape distortions and interfacial strength, as they are directly related to the quality and reliability of additive manufactured soft materials. Then, design principles and manufacturing strategies for bio-inspired composites, which makes up a large part of current researches on additive manufactured soft materials, are summarized integrally from three aspects. In addition, basic mechanical considerations for additive manufactured 4D shape changing structures are explained, together with the review of recent theories and numerical approaches. Finally, suggestions and perspectives are given for future developments of soft material additive manufacturing.","PeriodicalId":74837,"journal":{"name":"Soft science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67660036","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":"Mechanically flexible and flame-retardant cellulose nanofibril-based films integrated with MXene and chitosan","authors":"","doi":"10.20517/ss.2022.20","DOIUrl":"https://doi.org/10.20517/ss.2022.20","url":null,"abstract":"","PeriodicalId":74837,"journal":{"name":"Soft science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67660137","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}
T. Wong, Chunki Yiu, Jingkun Zhou, Zhenhao Song, Yiming Liu, Ling Zhao, K. Yao, Woo-Mi Park, Woojung Yoo, E. Song, Zhaoqian Xie, Xinge Yu
Flexible electronic skin (e-skin) has been successfully utilized in diverse applications, including prosthesis sensing, body-motion monitoring and human-machine interfaces, due to its excellent mechanical properties and electrical characteristics. However, current e-skins are still relatively thick (> 10 µ m) and uncomfortable for long-term usage on the human body. Herein, an ultrathin skin-integrated strain sensor with miniaturized dimensions, based on the piezoresistive effect, with excellent stability and robustness, is introduced. The fractal curve-shaped Au electrode in a serpentine format, which is the dominant component of the strain sensor, is sensitive to ambient strain variations and can turn the mechanical motion into a stable electrical signal output. With the advanced design of metallic electrodes, the device presents good operational stability and excellent mechanical tolerance towards bending, stretching and twisting. The stain sensor allows intimate mounting onto the human epidermal surface for the detection of body motion. By adopting a liquid bandage as an encapsulation layer, the device exhibits an ultrathin thickness (6.2 µ m), high sensitivity towards mechanical deformations and capability for the clear
{"title":"Tattoo-like epidermal electronics as skin sensors for human machine interfaces","authors":"T. Wong, Chunki Yiu, Jingkun Zhou, Zhenhao Song, Yiming Liu, Ling Zhao, K. Yao, Woo-Mi Park, Woojung Yoo, E. Song, Zhaoqian Xie, Xinge Yu","doi":"10.20517/ss.2021.09","DOIUrl":"https://doi.org/10.20517/ss.2021.09","url":null,"abstract":"Flexible electronic skin (e-skin) has been successfully utilized in diverse applications, including prosthesis sensing, body-motion monitoring and human-machine interfaces, due to its excellent mechanical properties and electrical characteristics. However, current e-skins are still relatively thick (> 10 µ m) and uncomfortable for long-term usage on the human body. Herein, an ultrathin skin-integrated strain sensor with miniaturized dimensions, based on the piezoresistive effect, with excellent stability and robustness, is introduced. The fractal curve-shaped Au electrode in a serpentine format, which is the dominant component of the strain sensor, is sensitive to ambient strain variations and can turn the mechanical motion into a stable electrical signal output. With the advanced design of metallic electrodes, the device presents good operational stability and excellent mechanical tolerance towards bending, stretching and twisting. The stain sensor allows intimate mounting onto the human epidermal surface for the detection of body motion. By adopting a liquid bandage as an encapsulation layer, the device exhibits an ultrathin thickness (6.2 µ m), high sensitivity towards mechanical deformations and capability for the clear","PeriodicalId":74837,"journal":{"name":"Soft science","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45597523","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}