As the Internet of Things advances,gesture recognition emerges as a prominent domain in human-machine interaction(HMI).However,interactive wearables based on conductive hydrogels for individuals with single-arm functi...As the Internet of Things advances,gesture recognition emerges as a prominent domain in human-machine interaction(HMI).However,interactive wearables based on conductive hydrogels for individuals with single-arm functionality or disabilities remain underexplored.Here,we devised a wearable one-handed keyboard with gesture recognition,employing machine learning algorithms and hydrogel-based mechanical sensors to boost productivity.PCG(PAM/CMC/rGO)hydrogels are composed of polyacrylamide(PAM),sodium carboxymethyl cellulose(CMC),and reduced graphene oxide(rGO),which function as a strain,pressure sensor,and electrode material.The PAM chains offer the gel’s elasticity by covalent cross-linking,while the biocompatible CMC improves the dispersion of rGO and promotes electromechanical properties.Integrating rGO sheets into the polymer matrix facilitates cross-linking and generates supple-mentary conductive pathways,thereby augmenting the gel system’s elasticity,sensitivity,and durability.Our hydrogel sensors include high sensitivity(gage factor(GF)=8.18,395.6%-551.96%)and superior pressure sensing capabilities(Sensitivity(S)=0.3116 kPa^(-1),0-9.82 kPa).Furthermore,we developed a wearable keyboard with up to 98.13%accuracy using convolutional neural networks and a custom data acquisition system.This study establishes the groundwork for creating multifunctional gel sensors for intelligent machines,wearable devices,and brain-computer interfaces.展开更多
Surgical robots are designed to provide enhanced precision and dexterity compared to manual surgical procedures,which mainly rely on multimodal sensing technologies for the surgeon to seamlessly operate the robotic ar...Surgical robots are designed to provide enhanced precision and dexterity compared to manual surgical procedures,which mainly rely on multimodal sensing technologies for the surgeon to seamlessly operate the robotic arms and instruments.Compared with single-mode sensors,optical and mechanical bi-modal sensors provide improved precision,enhanced safety,and robustness of human-machine interaction systems.Here,the template-guided and pneumatic printing technologies are combined to construct perovskite and graphene parallel structures with both optical and mechanical sensing capabilities.The printed uniformly crystallized perovskite microstructure exhibits fast and sensitive photoelectric response characteristics,enabling shadow recognition functionality.The combination of graphene and elastic rubber endows the great printability to prepare parallel structures near the perovskite arrays for force sensing capabilities.Thus,the printed perovskite and graphene structures possess non-contact optical sensing capabilities to detect hand position by recognizing shadows between the hand and the sensor,as well as contact mechanical sensing capabilities to detect touch force applied by the hand.It provides a synergistic platform for real-time and multidimensional feedback to improve human-machine interaction.展开更多
Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexib...Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexible fiber sensors.Through the preform-tofiber manufacturing technique,a variety of fiber sensors with complex functionalities spanning from the nanoscale to kilometer scale can be automated in a short time.Examples include temperature,acoustic,mechanical,chemical,biological,optoelectronic,and multifunctional sensors,which operate on diverse sensing principles such as resistance,capacitance,piezoelectricity,triboelectricity,photoelectricity,and thermoelectricity.This review outlines the principles of the thermal drawing process and provides a detailed overview of the latest advancements in various thermally drawn fiber sensors.Finally,the future developments of thermally drawn fiber sensors are discussed.展开更多
Two-dimensional(2D)materials have great potential in the fields of flexible electronics and photoelectronic devices due to their unique properties derived by special structures.The study of the mechanical properties o...Two-dimensional(2D)materials have great potential in the fields of flexible electronics and photoelectronic devices due to their unique properties derived by special structures.The study of the mechanical properties of 2D materials plays an important role in next-generation flexible mechanical electronic device applications.Unfortunately,traditional experiment models and measurement methods are not suitable for 2D materials due to their atomically ultrathin thickness,which limits both the theoretical research and practical value of the 2D materials.In this review,we briefly summarize the characterization of mechanical properties of 2D materials by in situ probe nanoindentation experiments,and discuss the effect of thickness,grain boundary,and interlayer interactions.We introduce the strain-induced effect on electrical properties and optical properties of 2D materials.Then,we generalize the mechanical sensors based on various 2D materials and their future potential applications in flexible and wearable electronic devices.Finally,we discuss the state of the art for the mechanical properties of 2D materials and their opportunities and challenges in both basic research and practical applications.展开更多
The strain and temperature sensing performance of fiber-optic Bragg gratings （FBGs） with soft polymeric coating, which can be used to sense internal strain in superconducting coils, are evaluated under variable cryo...The strain and temperature sensing performance of fiber-optic Bragg gratings （FBGs） with soft polymeric coating, which can be used to sense internal strain in superconducting coils, are evaluated under variable cryogenic field and magnetic field. The response to a temperature and strain change of coated-soft polymeric FBGs is tested by comparing with those of coated-metal FBGs. The results indicate that the coated-soft polymeric FBGs can freely detect temperature and thermal strain, their At variable magnetic field, the tested results indicate accuracy and repeatability are also discussed in detail. that the cross-coupling effects of FBGs with different matrixes are not negligible to measure electromagnetic strain during fast excitation. The present results are expected to be able to provide basis measurements on the strain of pulsed superconducting magnet/cable （cable- around-conduit conductors, cable-in-conduit conductors）, independently or utilized together with other strain measurement methods.展开更多
To realize a hyperconnected smart society with high productivity,advances in flexible sensing technology are highly needed.Nowadays,flexible sensing technology has witnessed improvements in both the hardware performan...To realize a hyperconnected smart society with high productivity,advances in flexible sensing technology are highly needed.Nowadays,flexible sensing technology has witnessed improvements in both the hardware performances of sensor devices and the data processing capabilities of the device’s software.Significant research efforts have been devoted to improving materials,sensing mechanism,and configurations of flexible sensing systems in a quest to fulfill the requirements of future technology.Meanwhile,advanced data analysis methods are being developed to extract useful information from increasingly complicated data collected by a single sensor or network of sensors.Machine learning(ML)as an important branch of artificial intelligence can efficiently handle such complex data,which can be multi-dimensional and multi-faceted,thus providing a powerful tool for easy interpretation of sensing data.In this review,the fundamental working mechanisms and common types of flexible mechanical sensors are firstly presented.Then how ML-assisted data interpretation improves the applications of flexible mechanical sensors and other closely-related sensors in various areas is elaborated,which includes health monitoring,human-machine interfaces,object/surface recognition,pressure prediction,and human posture/motion identification.Finally,the advantages,challenges,and future perspectives associated with the fusion of flexible mechanical sensing technology and ML algorithms are discussed.These will give significant insights to enable the advancement of next-generation artificial flexible mechanical sensing.展开更多
Because of the interesting and multifunctional properties,recently,ZnO nanostructures are considered as excellent material for fabrication of highly sensitive and selective gas sensors.Thus,ZnO nanomaterials are widel...Because of the interesting and multifunctional properties,recently,ZnO nanostructures are considered as excellent material for fabrication of highly sensitive and selective gas sensors.Thus,ZnO nanomaterials are widely used to fabricate efficient gas sensors for the detection of various hazardous and toxic gases.The presented review article is focusing on the recent developments of NO2gas sensors based on ZnO nanomaterials.The review presents the general introduction of some metal oxide nanomaterials for gas sensing application and finally focusing on the structure of ZnO and its gas sensing mechanisms.Basic gas sensing characteristics such as gas response,response time,recovery time,selectivity,detection limit,stability and recyclability,etc are also discussed in this article.Further,the utilization of various ZnO nanomaterials such as nanorods,nanowires,nano-micro flowers,quantum dots,thin films and nanosheets,etc for the fabrication of NO2gas sensors are also presented.Moreover,various factors such as NO2concentrations,annealing temperature,ZnO morphologies and particle sizes,relative humidity,operating temperatures which are affecting the NO2gas sensing properties are discussed in this review.Finally,the review article is concluded and future directions are presented.展开更多
With the rapid development of the intelligent technology,flexible sensors have widely applied in wearable electronic products,human-computer interaction,soft robots,health care and other emerging fields.At present,mec...With the rapid development of the intelligent technology,flexible sensors have widely applied in wearable electronic products,human-computer interaction,soft robots,health care and other emerging fields.At present,mechanical sensors are based on resistance or capacitance changes alone to achieve a perceived response to force.Meanwhile the methods of flexible mechanical sensors to improve the sensitivity are mainly micro-structuring of the electrode or dielectric layer,which is a complicated process and less probing of the electrode shape.Therefore,this paper proposes a flexible sensor based liquid metal to measure mechanics through resistive-capacitive coupling.Through testing,we obtained the optimal preparation scheme.We also explored the mechanical properties of the sensor design with different combinations of liquid metal electrode shapes using simulation,and then tested the mechanical properties of the double helix liquid metal sensor prepared according to the model structure.With resistive-capacitive coupling,the sensor can achieve a sensitivity of 0.4653 kPa^(-1) with a response range of 10~343 Pa,and it has good tensile and compressive response,and cyclic stability.This study provides a new structural design direction for the subsequent application of liquid metal in flexible sensing with high sensitivity.展开更多
The development of automation industry is inseparable from the progress of sensing technology.As a promising self-powered sensing technology,the durability and stability of triboelectric sensor(TES)have always been in...The development of automation industry is inseparable from the progress of sensing technology.As a promising self-powered sensing technology,the durability and stability of triboelectric sensor(TES)have always been inevitable challenges.Herein,a continuous charge supplement(CCS)strategy and an adaptive signal processing(ASP)method are proposed to improve the lifetime and robustness of TES.The CCS uses low friction brushes to increase the surface charge density of the dielectric,ensuring the reliability of sensing.A triboelectric mechanical motion sensor(TMMS)with CCS is designed,and its electrical signal is hardly attenuated after 1.5 million cycles after reasonable parameter optimization,which is unprecedented in linear TESs.After that,the dynamic characteristics of the CCS-TMMS are analyzed with error rates of less than 1%and 2%for displacement and velocity,respectively,and a signal-to-noise ratio of more than 35 dB.Also,the ASP used a signal conditioning circuit for impedance matching and analog-to-digital conversion to achieve a stable output of digital signals,while the integrated design and manufacture of each hardware module is achieved.Finally,an intelligent logistics transmission system(ILTS)capable of wirelessly monitoring multiple motion parameters is developed.This work is expected to contribute to automation industries such as smart factories and unmanned warehousing.展开更多
Skin,the largest organ in the human body,is sensitive to external stimuli.In recent years,an increasing number of skin-inspired electronics,including wearable electronics,implantable electronics,and electronic skin,ha...Skin,the largest organ in the human body,is sensitive to external stimuli.In recent years,an increasing number of skin-inspired electronics,including wearable electronics,implantable electronics,and electronic skin,have been developed because of their broad applications in healthcare and robotics.Physical sensors are one of the key building blocks of skin-inspired electronics.Typical physical sensors include mechanical sensors,temperature sensors,humidity sensors,electrophysiological sensors,and so on.In this review,we systematically review the latest advances of skin-inspired mechanical sensors,temperature sensors,and humidity sensors.The working mechanisms,key materials,device structures,and performance of various physical sensors are summarized and discussed in detail.Their applications in health monitoring,human disease diagnosis and treatment,and intelligent robots are reviewed.In addition,several novel properties of skin-inspired physical sensors such as versatility,self-healability,and implantability are introduced.Finally,the existing challenges and future perspectives of physical sensors for practical applications are discussed and proposed.展开更多
Three-dimensional(3D)functional systems are of rapidly growing interest over the past decade,from the perspective of both the fundamental and applied research.In particular,tremendous efforts have been devoted to the ...Three-dimensional(3D)functional systems are of rapidly growing interest over the past decade,from the perspective of both the fundamental and applied research.In particular,tremendous efforts have been devoted to the developments of 3D flexible,physical sensors,partly because of their substantial advantages over planar counterparts in many specific performances.In this review,we summarize recent advances in diverse categories of 3D flexible physical sensors,covering the photoelectric,mechanical,temperature,magnetic,and other physical sensors.This review mainly focuses on their design strategies,working principles and applications.Finally,we offer an outlook on the future developments,and provide perspectives on the remaining challenges and opportunities in this area.展开更多
In this paper, we report some results about the effects of varying the wavelength in a structure of a non-holographic fiber specklegram sensor. In these arrangements, the speckle pattern produced by a multi-mode optic...In this paper, we report some results about the effects of varying the wavelength in a structure of a non-holographic fiber specklegram sensor. In these arrangements, the speckle pattern produced by a multi-mode optical fiber is coupled to the asingle-mode optical fiber with lower numerical aperture, which produces a filtering effect that can be used as an optical transduction mechanism. The influence of the wavelength on the sensor performance is evaluated by changing the laser wavelength, and a strong effect on the linearity and reproducibility of its response is found. Lasers emitting at 1310nm, 1550nm, and 1625nm are used.展开更多
The remarkable ability of biological systems to sense and adapt to complex environmental conditions has inspired the design of next-generation electronics with advanced functionalities.This review focuses on emerging ...The remarkable ability of biological systems to sense and adapt to complex environmental conditions has inspired the design of next-generation electronics with advanced functionalities.This review focuses on emerging bio-inspired strategies for the development of flexible and stretchable electronics that can accommodate mechanical deformations and integrate seamlessly with biological systems.We will provide an overview of the practical considerations in the materials and structure designs of flexible and stretchable electronics.Recent progress in bio-inspired pressure/strain sensors,stretchable electrodes,mesh electronics,and flexible energy devices are then discussed,with an emphasis on their unconventional micro/nanostructure designs and advanced functionalities.Finally,current challenges and future perspectives are identified and discussed.展开更多
Background The Jiangmen Underground Neutrino Observatory(JUNO)is a multipurpose neutrino experiment designed to determine neutrino mass hierarchy and precisely measure oscillation parameters and study the solar neutri...Background The Jiangmen Underground Neutrino Observatory(JUNO)is a multipurpose neutrino experiment designed to determine neutrino mass hierarchy and precisely measure oscillation parameters and study the solar neutrino,supernova neutrino,geo-neutrino,etc.JUNO's central detector(CD)has 20 kilo-ton liquid scintillator as target mass,which is contained by a huge acrylic sphere with the inner diameter of 35.4 m,and the acrylic sphere is supported by a stainless steel structure through 590 connecting bars.Motivation Part of the connecting bars bear pull force and the other bars bear push force.There is a direct relationship between the stress of connecting bars and that of acrylic sphere.For the installation process of the CD,the pretightening force and axial force of the connecting bars should be monitored with accuracy,and for the filling process and running condition,the precise measurement of axial force can indicate the safety of structure of the CD.Methods Statistical method was used to evaluate the performance of measurement schemes,and 4-fiber Bragg grating measurement scheme was determined to be the final scheme,which can get the measurement uncertainty better than 0.7 kN.Performance of different measurement schemes are discussed in detail,and some related finite element analysis and evalu-ation method are also introduced in this paper.展开更多
基金supported by the China Postdoctoral Science Foundation(No.2022BG011)the Fundamental Research Funds for Central Universities(No.2020CDJ-LHZZ-077)+1 种基金the Natural Science Foundation of Chongqing,China(No.c stc2020jcyj-msxmX0397)the Fundamental Research Funds for Central Universities(No.00007717).
文摘As the Internet of Things advances,gesture recognition emerges as a prominent domain in human-machine interaction(HMI).However,interactive wearables based on conductive hydrogels for individuals with single-arm functionality or disabilities remain underexplored.Here,we devised a wearable one-handed keyboard with gesture recognition,employing machine learning algorithms and hydrogel-based mechanical sensors to boost productivity.PCG(PAM/CMC/rGO)hydrogels are composed of polyacrylamide(PAM),sodium carboxymethyl cellulose(CMC),and reduced graphene oxide(rGO),which function as a strain,pressure sensor,and electrode material.The PAM chains offer the gel’s elasticity by covalent cross-linking,while the biocompatible CMC improves the dispersion of rGO and promotes electromechanical properties.Integrating rGO sheets into the polymer matrix facilitates cross-linking and generates supple-mentary conductive pathways,thereby augmenting the gel system’s elasticity,sensitivity,and durability.Our hydrogel sensors include high sensitivity(gage factor(GF)=8.18,395.6%-551.96%)and superior pressure sensing capabilities(Sensitivity(S)=0.3116 kPa^(-1),0-9.82 kPa).Furthermore,we developed a wearable keyboard with up to 98.13%accuracy using convolutional neural networks and a custom data acquisition system.This study establishes the groundwork for creating multifunctional gel sensors for intelligent machines,wearable devices,and brain-computer interfaces.
基金supported by the National Natural Science Foundation of China(Grant Nos.52222313,22075296,52321006,T2394480,and T2394484)the National Key R&D Program of China(Grant Nos.2023YFE0111500,2021YFB3200701,and 2022YFB4700804)+1 种基金Beijing National Laboratory for Molecular Sciences(Grant No.BNLMSCXXM-202005)Beijing Municipal Science&Technology Commission(Grant No.Z231100005923039).
文摘Surgical robots are designed to provide enhanced precision and dexterity compared to manual surgical procedures,which mainly rely on multimodal sensing technologies for the surgeon to seamlessly operate the robotic arms and instruments.Compared with single-mode sensors,optical and mechanical bi-modal sensors provide improved precision,enhanced safety,and robustness of human-machine interaction systems.Here,the template-guided and pneumatic printing technologies are combined to construct perovskite and graphene parallel structures with both optical and mechanical sensing capabilities.The printed uniformly crystallized perovskite microstructure exhibits fast and sensitive photoelectric response characteristics,enabling shadow recognition functionality.The combination of graphene and elastic rubber endows the great printability to prepare parallel structures near the perovskite arrays for force sensing capabilities.Thus,the printed perovskite and graphene structures possess non-contact optical sensing capabilities to detect hand position by recognizing shadows between the hand and the sensor,as well as contact mechanical sensing capabilities to detect touch force applied by the hand.It provides a synergistic platform for real-time and multidimensional feedback to improve human-machine interaction.
基金supported by the National Key Research and Development Program of China(2023YFB3809800)the National Natural Science Foundation of China(52172249,52525601)+2 种基金the Chinese Academy of Sciences Talents Program(E2290701)the Jiangsu Province Talents Program(JSSCRC2023545)the Special Fund Project of Carbon Peaking Carbon Neutrality Science and Technology Innovation of Jiangsu Province(BE2022011).
文摘Flexible fiber sensors,However,traditional methods face challenges in fabricating low-cost,large-scale fiber sensors.In recent years,the thermal drawing process has rapidly advanced,offering a novel approach to flexible fiber sensors.Through the preform-tofiber manufacturing technique,a variety of fiber sensors with complex functionalities spanning from the nanoscale to kilometer scale can be automated in a short time.Examples include temperature,acoustic,mechanical,chemical,biological,optoelectronic,and multifunctional sensors,which operate on diverse sensing principles such as resistance,capacitance,piezoelectricity,triboelectricity,photoelectricity,and thermoelectricity.This review outlines the principles of the thermal drawing process and provides a detailed overview of the latest advancements in various thermally drawn fiber sensors.Finally,the future developments of thermally drawn fiber sensors are discussed.
基金Fundamental Research Funds for the Central Universities,Grant/Award Numbers:31020190QD010,3102019PY004,3102019JC004Ministry of Education-Singapore,Grant/Award Numbers:MOE2015-T2-2-043,MOE2017-T2-2-136,Tier 1 RG7/18+2 种基金National Natural Science Foundation of China,Grant/Award Number:11904289Natural Science Foundation of Shaanxi Province,Grant/Award Number:2019JQ-613Start-up funds from Northwestern Polytechnical University,Grant/Award Numbers:19SH020159,19SH020123。
文摘Two-dimensional(2D)materials have great potential in the fields of flexible electronics and photoelectronic devices due to their unique properties derived by special structures.The study of the mechanical properties of 2D materials plays an important role in next-generation flexible mechanical electronic device applications.Unfortunately,traditional experiment models and measurement methods are not suitable for 2D materials due to their atomically ultrathin thickness,which limits both the theoretical research and practical value of the 2D materials.In this review,we briefly summarize the characterization of mechanical properties of 2D materials by in situ probe nanoindentation experiments,and discuss the effect of thickness,grain boundary,and interlayer interactions.We introduce the strain-induced effect on electrical properties and optical properties of 2D materials.Then,we generalize the mechanical sensors based on various 2D materials and their future potential applications in flexible and wearable electronic devices.Finally,we discuss the state of the art for the mechanical properties of 2D materials and their opportunities and challenges in both basic research and practical applications.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11302225,11121202 and 11327802the National Key Project of Magneto-Constrained Fusion Energy Development Program under Grant No 2013GB110002the Postdoctoral Science Foundation of China under Grant No 2014M560820
文摘The strain and temperature sensing performance of fiber-optic Bragg gratings （FBGs） with soft polymeric coating, which can be used to sense internal strain in superconducting coils, are evaluated under variable cryogenic field and magnetic field. The response to a temperature and strain change of coated-soft polymeric FBGs is tested by comparing with those of coated-metal FBGs. The results indicate that the coated-soft polymeric FBGs can freely detect temperature and thermal strain, their At variable magnetic field, the tested results indicate accuracy and repeatability are also discussed in detail. that the cross-coupling effects of FBGs with different matrixes are not negligible to measure electromagnetic strain during fast excitation. The present results are expected to be able to provide basis measurements on the strain of pulsed superconducting magnet/cable （cable- around-conduit conductors, cable-in-conduit conductors）, independently or utilized together with other strain measurement methods.
基金support from National Natural Science Foundation of China(Nos.62274140,61904141,52173234)the State Key Laboratory of Mechanics and Control of Mechanical Structures(Nanjing University of Aeronautics and Astronautics)(Grant No.MCMS-E-0422G03)the Shenzhen-Hong Kong-Macao Technology Research Program(Type C,202011033000145,SGDX2020110309300301).
文摘To realize a hyperconnected smart society with high productivity,advances in flexible sensing technology are highly needed.Nowadays,flexible sensing technology has witnessed improvements in both the hardware performances of sensor devices and the data processing capabilities of the device’s software.Significant research efforts have been devoted to improving materials,sensing mechanism,and configurations of flexible sensing systems in a quest to fulfill the requirements of future technology.Meanwhile,advanced data analysis methods are being developed to extract useful information from increasingly complicated data collected by a single sensor or network of sensors.Machine learning(ML)as an important branch of artificial intelligence can efficiently handle such complex data,which can be multi-dimensional and multi-faceted,thus providing a powerful tool for easy interpretation of sensing data.In this review,the fundamental working mechanisms and common types of flexible mechanical sensors are firstly presented.Then how ML-assisted data interpretation improves the applications of flexible mechanical sensors and other closely-related sensors in various areas is elaborated,which includes health monitoring,human-machine interfaces,object/surface recognition,pressure prediction,and human posture/motion identification.Finally,the advantages,challenges,and future perspectives associated with the fusion of flexible mechanical sensing technology and ML algorithms are discussed.These will give significant insights to enable the advancement of next-generation artificial flexible mechanical sensing.
基金supported by NSTIP strategic technologies programs,number(12-NAN2551-02)in the Kingdom of Saudi Arabia
文摘Because of the interesting and multifunctional properties,recently,ZnO nanostructures are considered as excellent material for fabrication of highly sensitive and selective gas sensors.Thus,ZnO nanomaterials are widely used to fabricate efficient gas sensors for the detection of various hazardous and toxic gases.The presented review article is focusing on the recent developments of NO2gas sensors based on ZnO nanomaterials.The review presents the general introduction of some metal oxide nanomaterials for gas sensing application and finally focusing on the structure of ZnO and its gas sensing mechanisms.Basic gas sensing characteristics such as gas response,response time,recovery time,selectivity,detection limit,stability and recyclability,etc are also discussed in this article.Further,the utilization of various ZnO nanomaterials such as nanorods,nanowires,nano-micro flowers,quantum dots,thin films and nanosheets,etc for the fabrication of NO2gas sensors are also presented.Moreover,various factors such as NO2concentrations,annealing temperature,ZnO morphologies and particle sizes,relative humidity,operating temperatures which are affecting the NO2gas sensing properties are discussed in this review.Finally,the review article is concluded and future directions are presented.
基金supported by Beijing Natural Science Foundation(Grand No.L223017)Foundation of China(12332019,U20A20390)the 111 Project(Project No.B13003).
文摘With the rapid development of the intelligent technology,flexible sensors have widely applied in wearable electronic products,human-computer interaction,soft robots,health care and other emerging fields.At present,mechanical sensors are based on resistance or capacitance changes alone to achieve a perceived response to force.Meanwhile the methods of flexible mechanical sensors to improve the sensitivity are mainly micro-structuring of the electrode or dielectric layer,which is a complicated process and less probing of the electrode shape.Therefore,this paper proposes a flexible sensor based liquid metal to measure mechanics through resistive-capacitive coupling.Through testing,we obtained the optimal preparation scheme.We also explored the mechanical properties of the sensor design with different combinations of liquid metal electrode shapes using simulation,and then tested the mechanical properties of the double helix liquid metal sensor prepared according to the model structure.With resistive-capacitive coupling,the sensor can achieve a sensitivity of 0.4653 kPa^(-1) with a response range of 10~343 Pa,and it has good tensile and compressive response,and cyclic stability.This study provides a new structural design direction for the subsequent application of liquid metal in flexible sensing with high sensitivity.
基金The authors are grateful for the support received from the National Key R&D Project from the Minister of Science and Technology(Nos.2021YFA1201601 and 2021YFA1201604)the Open Research Project Programme of the State Key Laboratory of Internet of Things for Smart City(University of Macao)(No.SKL-IoTSC(UM)-2021-2023/ORPF/A17/2022).
文摘The development of automation industry is inseparable from the progress of sensing technology.As a promising self-powered sensing technology,the durability and stability of triboelectric sensor(TES)have always been inevitable challenges.Herein,a continuous charge supplement(CCS)strategy and an adaptive signal processing(ASP)method are proposed to improve the lifetime and robustness of TES.The CCS uses low friction brushes to increase the surface charge density of the dielectric,ensuring the reliability of sensing.A triboelectric mechanical motion sensor(TMMS)with CCS is designed,and its electrical signal is hardly attenuated after 1.5 million cycles after reasonable parameter optimization,which is unprecedented in linear TESs.After that,the dynamic characteristics of the CCS-TMMS are analyzed with error rates of less than 1%and 2%for displacement and velocity,respectively,and a signal-to-noise ratio of more than 35 dB.Also,the ASP used a signal conditioning circuit for impedance matching and analog-to-digital conversion to achieve a stable output of digital signals,while the integrated design and manufacture of each hardware module is achieved.Finally,an intelligent logistics transmission system(ILTS)capable of wirelessly monitoring multiple motion parameters is developed.This work is expected to contribute to automation industries such as smart factories and unmanned warehousing.
基金National Key Basic Research and Development Program,Grant/Award Number:2016YFA0200103National Natural Science Foundation of China,Grant/Award Numbers:21975141,51672153National Program for Support of Top-notch Young Professionals,Grant/Award Number:N/A。
文摘Skin,the largest organ in the human body,is sensitive to external stimuli.In recent years,an increasing number of skin-inspired electronics,including wearable electronics,implantable electronics,and electronic skin,have been developed because of their broad applications in healthcare and robotics.Physical sensors are one of the key building blocks of skin-inspired electronics.Typical physical sensors include mechanical sensors,temperature sensors,humidity sensors,electrophysiological sensors,and so on.In this review,we systematically review the latest advances of skin-inspired mechanical sensors,temperature sensors,and humidity sensors.The working mechanisms,key materials,device structures,and performance of various physical sensors are summarized and discussed in detail.Their applications in health monitoring,human disease diagnosis and treatment,and intelligent robots are reviewed.In addition,several novel properties of skin-inspired physical sensors such as versatility,self-healability,and implantability are introduced.Finally,the existing challenges and future perspectives of physical sensors for practical applications are discussed and proposed.
基金supported by the Henry Fok Education Foundation[171003]National Natural Science Foundation of China[12002189,12050004,11921002,61904095]the Institute for Guo Qiang,Tsinghua University[2019GQG1012]。
文摘Three-dimensional(3D)functional systems are of rapidly growing interest over the past decade,from the perspective of both the fundamental and applied research.In particular,tremendous efforts have been devoted to the developments of 3D flexible,physical sensors,partly because of their substantial advantages over planar counterparts in many specific performances.In this review,we summarize recent advances in diverse categories of 3D flexible physical sensors,covering the photoelectric,mechanical,temperature,magnetic,and other physical sensors.This review mainly focuses on their design strategies,working principles and applications.Finally,we offer an outlook on the future developments,and provide perspectives on the remaining challenges and opportunities in this area.
文摘In this paper, we report some results about the effects of varying the wavelength in a structure of a non-holographic fiber specklegram sensor. In these arrangements, the speckle pattern produced by a multi-mode optical fiber is coupled to the asingle-mode optical fiber with lower numerical aperture, which produces a filtering effect that can be used as an optical transduction mechanism. The influence of the wavelength on the sensor performance is evaluated by changing the laser wavelength, and a strong effect on the linearity and reproducibility of its response is found. Lasers emitting at 1310nm, 1550nm, and 1625nm are used.
基金supported by the National Natural Science Foundation of China (52373201,52103252 and 52090033)the Fundamental Research Funds for the Central Universities (2232024Y-01)the State Key Laboratory for Modification of Chemical Fibers and Polymer Materials (Donghua University)。
基金We thank Dr.Jidong Shi from The Hong Kong Polytechnic University for helpful discussions.This work is supported by the National Natural Science Foundation of China(Nos.21790393 and 51972073)Frontier Research Program of the Chinese Academy of Sciences(No.XDB32030100).
文摘The remarkable ability of biological systems to sense and adapt to complex environmental conditions has inspired the design of next-generation electronics with advanced functionalities.This review focuses on emerging bio-inspired strategies for the development of flexible and stretchable electronics that can accommodate mechanical deformations and integrate seamlessly with biological systems.We will provide an overview of the practical considerations in the materials and structure designs of flexible and stretchable electronics.Recent progress in bio-inspired pressure/strain sensors,stretchable electrodes,mesh electronics,and flexible energy devices are then discussed,with an emphasis on their unconventional micro/nanostructure designs and advanced functionalities.Finally,current challenges and future perspectives are identified and discussed.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA100102)
文摘Background The Jiangmen Underground Neutrino Observatory(JUNO)is a multipurpose neutrino experiment designed to determine neutrino mass hierarchy and precisely measure oscillation parameters and study the solar neutrino,supernova neutrino,geo-neutrino,etc.JUNO's central detector(CD)has 20 kilo-ton liquid scintillator as target mass,which is contained by a huge acrylic sphere with the inner diameter of 35.4 m,and the acrylic sphere is supported by a stainless steel structure through 590 connecting bars.Motivation Part of the connecting bars bear pull force and the other bars bear push force.There is a direct relationship between the stress of connecting bars and that of acrylic sphere.For the installation process of the CD,the pretightening force and axial force of the connecting bars should be monitored with accuracy,and for the filling process and running condition,the precise measurement of axial force can indicate the safety of structure of the CD.Methods Statistical method was used to evaluate the performance of measurement schemes,and 4-fiber Bragg grating measurement scheme was determined to be the final scheme,which can get the measurement uncertainty better than 0.7 kN.Performance of different measurement schemes are discussed in detail,and some related finite element analysis and evalu-ation method are also introduced in this paper.
