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Impedance Spectroscopy (IWIS), International Workshop on

作者： Bilel Ghoul Rim Barioul Mariem Hafsa Salwa Sahnoun Ahmed Fakhfakh Olfa Kanoun Measurement and Sensor Technology Faculty of Electrical Engineering and Information Technology Chemnitz University of Technology Chemnitz Germany Laboratory of Signals Systems Artificial Intelligence and Networks Digital Research Centre of Sfax National School of Electronics and Telecommunications of Sfax Technopole of Sfax Ons City Tunisia LATIS- Laboratory of Advanced Technology and Intelligent Systems Université de Sousse Ecole Nationale d'Ingénieurs de Sousse Sousse Tunisie

ISBN: (数字)9798331507626

ISBN: (纸本)9798331507633

Electrical Impedance Tomography (EIT) is increasingly being used to recognize hand signs due to its internal sensing capabilities. EIT systems operate by injecting a lowamplitude electrical current into the forearm through a set of electrodes and recording the resulting voltages for signal processing. However, this method can result in high power consumption in wearable hand gesture recognition applications due to the current injection-based principle. To overcome this limitation, our investigation focuses on reducing the power consumption of EIT systems by minimizing the number of injected currents. In this study, we propose an injection reduction approach based on ambiguity analysis and the reduction of non-relevant voltage readings. As a result, the proposed method eliminates 3 out of 8 current injections, leading to a 37.5 % reduction in power consumption. This decreases energy usage by 22.5 mW per measurement for a current amplitude of ${150} \mu \mathrm{A}$ over 10 trials. Further, acquisition time was reduced from 1 second to 0.6 seconds. The classification accuracy using the KNN classifier reached 99 % with full measurements and 96 % with reduced injections. Moreover, a comparative analysis of the reduced injections to forearm anatomy is performed. It demonstrates that bones and high-density muscle areas can affect the current flow and result in inaccurate measurements. These findings demonstrate the potential for reducing current injections in EIT to produce more energy-efficient wearable hand sign recognition systems.

关键词： Hands Electrodes Electrical impedance tomography Electric potential Power demand Accuracy Current measurement Muscles Nearest neighbor methods Impedance

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Study for the Minimization of the Number of Frequencies for Cole-Cole Model for Bioimpedance Spectroscopy

Study for the Minimization of the Number of Frequencies for ...

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Impedance Spectroscopy (IWIS), International Workshop on

作者： Cherif Ouni Nour Ammar Ahmed Yahia Kallel Hanen Nouri Bilel Ben Atitallah Ahmed Fakhfakh Olfa Kanoun Measurement and Sensor Technology Faculty of Electrical Engineering and Information Technology Chemnitz University of Technology Chemnitz Germany Laboratory of Signals Systems Artificial Intelligence and Networks Digital Research Centre of Sfax National School of Electronics and Telecommunications of Sfax Technopole of Sfax Ons City Tunisia Control and Energy Management Laboratory National Engineering School of Sfax University of Sfax Sfax Tunisia

Wearable bioimpedance devices are a growing trend toward low-power and portable devices. These devices offer many advantages, including portability, convenience, and integration into daily life. However, wearable BIS devices face power consumption issues. Reducing the frequencies in the stimulation signal has been proposed to address this issue. This study investigates the effect of minimizing the number of excitation signals on BIS performance using synthetic data from a Cole-Cole model. In the absence of noise, the simulation indicates that two frequencies are sufficient to reconstruct the impedance of a dispersion. When simulating noise variance levels of 10%, 5%, and 1%, the accuracy of component values and their relationship to frequency is affected. It should be noted that beyond a certain threshold, the results or component values are not significantly improved in the presence of noise by increasing the number of frequencies. However, when dealing with noise levels up to about 1%, it is critical to use at least three frequencies to accurately reconstruct the impedance spectrum. This approach reduces power consumption while maintaining the accuracy of the BIS measurements.

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Planar mapping of the liquid fraction of froth using ultrasound Flächige Darstellung des Wassergehaltes von Schaum mittels Ultraschall 21

Planar mapping of the liquid fraction of froth using ultraso...

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21. ITG/GMA-Fachtagung sensoren und Messsysteme - 21st ITG/GMA Conference on sensors and Measuring Systems

作者： Emmerich, Hannes Knüpfer, Leon Trtik, Pavel Eckert, Kerstin Heitkam, Sascha Starke, Eric Weik, David Büttner, Lars Czarske, Jürgen Technical University Dresden Laboratory of Measurement and Sensor System Techniques Dresden01069 Germany Helmholtz-Zentrum Dresden-Rossendorf Institute of Fluid Dynamics Dresden01328 Germany Paul Scherrer Institut Laboratory for Neutron Scattering and Imaging Villigen5232 Switzerland Technical University Dresden Institute of Process Engineering and Environmental Technology Dresden01069 Germany SICK Engineering GmbH Bergener Ring 27 Ottendorf-Okrilla01458 Germany

ISBN: (纸本)9783800758364

Flotation processes are essential processes for resource separation, the monitoring of which can save vast amounts of water and energy. To control them, it is necessary to measure the phase fractions present in the froth. Currently, no suitable measurement method exists that can be easily integrated into the existing process and has a penetration depth of more than 5 cm. Therefore, in this paper we present a measurement system for determining the liquid distribution in foam using ultrasound. To counteract the strong attenuating effect of the foam on the ultrasound, we use low-frequency probes with a center frequency of 135 kHz. Electrodes determine an integral liquid fraction by conductivity measurement. Within a liquid range of 0.17 ·10−2 to 0.82 ·10−2, the measurement system was first calibrated for a penetration depth of 9.2 cm and validated by simultaneous neutron imaging. An absolute and relative measurement uncertainty of 0.23 ·10−2 and 42.5 % was the respective result. A resolution of 7.5 mm in the axial, 13 mm in lateral direction and 1 Hz in time were obtained. In a dynamic inhomogeneous case, the measurement system was additionally validated for a use case. This investigation represents a first step towards process optimization in flotation processes. © VDE VERLAG GMBH ∙ Berlin ∙ Offenbach.

关键词： Ultrasonics

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Flexible Human-Machine Interface Touch Pad S Based on Double-Network Solid-State Ionic Conductive Elastomers

SSRN

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SSRN 2024年

作者： Zhan, Wang Zhang, Qi Ye, Zhilu Yang, Zihao Wang, Yijing Zhang, Cuiling Zhang, Zeying Xue, Li Ma, Feng Wang, Zhiguang Peng, Niancai Jiang, Zhuangde Lyu, Yi Liu, Ming Zhang, Xiaohui State Key Laboratory for Manufacturing Systems Engineering The Key Laboratory of Biomedical Information Engineering of Ministry of Education Center for Mitochondrial Biology and Medicine School of Life Science and Technology International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technology Xi'an Key Laboratory for Biomedical Testing and High-end Equipment Xi'an Jiaotong University Shannxi Xi’an710049 China National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine Shaanxi Provincial Key Laboratory of Magnetic Medicine Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong University No. 277 West Yanta Road Shaanxi Xi’an710061 China State Key Laboratory for Manufacturing Systems Engineering Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education Engineering Research Center of Spin Quantum Sensor Chips Universities of Shaanxi Province School of Electronic Science and Engineering Xi'an Jiaotong University Xi’an710049 China State Key Laboratory for Manufacturing Systems Engineering School of Instrument Science and Technology International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technology Xi’an Key Laboratory for Biomedical Testing and High-end Equipment Xi’an Jiaotong University Xi’an710054 China State Key Laboratory for Manufacturing Systems Engineering International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technology Xi’an Jiaotong University Shaanxi Xi’an710049 China

In the rapidly evolving fields of artificial intelligence and the Internet of Things (IoTs), traditional rigid touch pads fall short in fulfilling the flexibility demands of cutting-edge human-machine interface technologies. Recent trends have seen the adoption of soft gel-based ionic conductors in the development of touch pads to enhance flexibility. Yet, these gel-based systems are hampered by intrinsic limitations like dehydration and ion/organic reagent leakage. Here, we report a flexible touch pad, ingeniously combining a surface-capacitive system with solid-state ionic conductive elastomers. Combination of salt-in-polymer and double-network structure strategies effectively addresses the longstanding trade-off between mechanical robustness and ionic conductivity. This pad supports a range of applications, from singular "point" interactions (flexible touch buttons) to "line" applications (stepless sound control and page turning) and finally, "surface" functionalities (game control and handwriting recognition). This research contributes significant insights to the advancement of next-generation human interfaces and IoTs. © 2024, The Authors. All rights reserved.

关键词： Interface states

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Research of laser atmospheric propagation of large-aperture antenna measurement 8

Research of laser atmospheric propagation of large-aperture ...

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8th International Conference on Speckle Metrology, Speckle 2023

作者： Zhang, Xuan Gao, Ming Wang, Hu Lin, Shangmin Jin, Yu Lai, Yunqiang Lv, Hong He, Wenlong Xi'an Technological University No.2 Xuefuzhonglu Road Shaanxi Xi'an710021 China Xi an Institute of Optics and Precision Mechanics Chinese Academy of Science No.17 Xinxi Road Shaanxi Xi'an710119 China University of Chinese Academy of Sciences No.1 Yanqihu East Rd Huairou District Beijing101408 China Xi an Space Sensor Optical Technology Engineering Research Center No.17 Xinxi Road Shaanxi Xi'an710119 China Key Laboratory of Space Precision Measurement Technology Chinese Academy of Sciences No.17 Xinxi Road Shaanxi Xi'an710119 China

ISBN: (数字)9781510674592

ISBN: (纸本)9781510674585

Laser measurement technology is widely used in antenna main reflector and subreflector deformation or pose measurement. Based on the laser measurement technology, atmospheric turbulence caused by the atmospheric characteristics or the convergence effect of the antenna itself will affect the refractive index disturbance during laser propagation, which affects the accuracy of the laser measurement of the antenna deformation or pose. In order to solve the problem of laser atmospheric propagation deflection caused by atmospheric turbulence on the near-ground of a large-aperture antenna, firstly, this paper decomposes the laser atmospheric propagation path into multiple isotropic air layers, calculates the atmospheric refractive index of each air layer, obtains the atmospheric refractive index of the whole laser propagation path through curve fitting methods, and then assesses the laser deflection. Secondly, the turbulence intensity under sunny daytime and cloudy nighttime are evaluated, the laser spot position deviation is compared and analyzed, and the matching relationship among turbulence intensity, theoretical deviation of the laser spots, and actual spot deviation is obtained. Finally, the deflection of laser atmospheric propagation is fitted and calculated by measuring environmental data matched to the actual experimental data of the Nanshan 26m radio telescope antenna, which verifies the effectiveness and feasibility of the proposed method. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.

关键词： Refractive index

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A Double Node Thin-Film Thermocouples for In-Situ measurement

A Double Node Thin-Film Thermocouples for In-Situ Measuremen...

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Automation, Robotics and Computer engineering (ICARCE), International Conference on

作者： Rong Ma Meiju Zhang Zhongkai Zhang Manguo Huang Xiaobo Liang Jiangjiang Liu Zhaojun Liu Bian Tian State Key Laboratory for Mechanical Manufacturing Systems Engineering Xi'an Jiaotong University Xi'an China Beijing Changcheng Aeronautic Measurement and Control Technology Research Institute Aviation Key Laboratory of Science and Technology on Special Condition Monitoring Sensor Technology Beijing China

ISBN: (纸本)9781665475495

The design, fabrication, testing and implementation of a new high-performance tungsten-rhenium thin film thermocouple are introduced. In this paper, tungsten-rhenium TFTCs are taken as the research object, after simulation analysis in COMSOL software and design, it is made by screen-printing technology and magnetron sputtering. This kind of thin film thermocouple primarily utilizes two kinds of electrode materials with varying composition combination, mainly tungsten with 5% rhenium and tungsten with 26% rhenium. Furthermore, high-temperature annealing is performed to maintain the mechanical properties and thus improve thermoelectric performance. The results demonstrate that the performance is reliable in the temperature range of 150-600 C° with a repeatability of 2.02%, providing application value for high-temperature in-situ sensing.

关键词： Temperature measurement Temperature distribution Thermocouples Tungsten Robot sensing systems Software sensors

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3D Geometry Design of the Human Thorax and Forward Calculation for Electrical Impedance Tomography

3D Geometry Design of the Human Thorax and Forward Calculati...

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IEEE SSD International Multi-Conference on Systems, Signals and Devices

作者： Youssef Alwaz Oumaima Bader Najoua Essoukri Ben Amara Olfa Kanoun National Engineering School of Sousse University of Sousse Sousse Tunisia Ecole Nationale d’Ingénieurs de Sousse LATIS- Laboratory of Advanced Technology and Intelligent Systems Université de Sousse Sousse Tunisie Professorship Measurement and Sensor Technology Technische Universität Chemnitz Chemnitz Germany

Electrical Impedance Tomography (EIT) for lung monitoring reflects the internal conductivity distribution of human tissues based on the boundary voltages that are measured through given electrodes. The electrodes are placed around the human chest. A low-amplitude current is injected through driving electrodes, and the boundary voltages are measured through other electrodes. In this context, this work has elaborated a strategy for the design of a 3D geometry of the human thorax based on sequential Computed Tomography (CT) scans. This geometry will be used for the simulation and analysis of the EIT measurement. Image segmentation has been used to extract the contour within different layers of the CT scans to form the final 3D geometry of the chest containing the lungs and the thorax. The generated geometry was later meshed and repaired. Mesh properties were controlled through the Skewness quality metric. A multi-layered design has been elaborated to mimic different human chest layers such as body fluid, muscle, and skin resulting in three models. These models had given the accuracy of 62%, 63%, and 65% of skewed elements relative to the existing volume. Later on, the electrodes were placed on the thorax geometry for EIT forward simulation, and the effect of the multi-layered model has been investigated.

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Human-Exoskeleton Interaction Force Estimation Based on Quasi-Direct Drive Actuators

Human-Exoskeleton Interaction Force Estimation Based on Quas...

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IEEE/RAS-EMBS International Conference on Biomedical Robotics and Biomechatronics (BioRob)

作者： Julian Seiler Niklas Schêfer Guoping Zhao Bastian Latsch Martin Grimmer Philipp Beckerle Mario Kupnik Measurement and Sensor Technology Group Technical University of Darmstadt Germany School of Mechanical Engineering Southeast University China Lauflabor Locomotion Laboratory Technical University of Darmstadt Germany Control and Cyber-Physical Systems Technical University of Darmstadt Germany Chair of Autonomous Systems and Mechatronics Friedrich-Alexander-Universität Erlangen Nurnberg Germany

ISBN: (数字)9798350386523

ISBN: (纸本)9798350386530

Exoskeletons have emerged as a promising tech-nological solution to provide functional compensation, training support, physical enhancement, and rehabilitation for an aging population. High torque density and control bandwidth are essential for exoskeleton actuation. In addition, monitoring and control of human-exoskeleton interaction forces is essential for the effectiveness, safety, and comfort of exoskeletons. Quasi-direct drives (QDD) have the potential to address the actuation requirements by enabling proprioceptive actuation with low mechanical output impedance. We present a test bench system to identify and validate the system dynamics, including torque constant, inertia, and friction properties of the QDD Cube-Mars AK10-9 V1.1. The actuator is employed in a hip exoskeleton to evaluate open-loop torque tracking and interaction force estimation in an assisted gait scenario with one participant walking on a treadmill. The model estimates interaction forces with a mean absolute error (MAE) of 2.78±0.58N (6.4% of rated force output). Model-based open-loop control improves the torque tracking MAE by 23%. Our analysis indicates that considering the soft coupling between human and exoskeleton has the potential to further improve the torque tracking and interaction force estimation accuracy. Altogether, the findings demonstrate that QDD actuation enables backdrivability, re-liable force estimation and controllable assistance, thereby providing an effective solution for exoskeleton actuation.

关键词： Actuators Torque Accuracy Friction Exoskeletons Force Dynamics Estimation Impedance Hip

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Lensless Near-Field Imaging with Enhanced Deep Super-Resolution Towards Real-Time Intraoperative Tumor Classification

Lensless Near-Field Imaging with Enhanced Deep Super-Resolut...

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Imaging Systems and Applications, ISA 2022

作者： Czarske, J.W. Wang, T. Wu, J. Uckermann, O. Galli, R. Kuschmierz, R. Laboratory of Measurement and Sensor Systems TU Dresden Helmholtzstrasse 18 Dresden01069 Germany TU Dresden Dresden Germany State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision Instruments Tsinghua University Beijing100084 China Department of Neurosurgery University Hospital Carl Gustav Carus TU Dresden Dresden Germany Division of Medical Biology Department of Psychiatry Faculty of Medicine University Hospital Carl Gustav Carus TU Dresden Germany Department of Medical Physics and Biomedical Engineering Faculty of Medicine Carl Gustav Carus TU Dresden Germany

A deep learning assisted fiber endoscopy is proposed. Resolutions beyond physical limitations are achieved, resulting in increased tumor diagnostic accuracy. This method is promising for rapid minimal-invasive intraop... 详细信息

ISBN: (纸本)9781557528209

关键词： Tumors

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Securing Data in Multimode Fibers by Exploiting Mode-Dependent Light Propagation Effects

arXiv

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arXiv 2022年

作者： Rothe, Stefan Besser, Karl-Ludwig Krause, David Kuschmierz, Robert Koukourakis, Nektarios Jorswieck, Eduard Czarske, Jürgen W. TU Dresden Faculty of Electrical and Computer Engineering Laboratory of Measurement and Sensor System Technique Dresden01062 Germany TU Braunschweig Faculty of Electrical Engineering Information Technology Physics Institute for Communications Technology Braunschweig38106 Germany TU Dresden Faculty of Physics Dresden01062 Germany

Multimode fibers hold great promise to advance data rates in optical communications but come with the challenge to compensate for modal crosstalk and mode-dependent losses, resulting in strong distortions. The holographic measurement of the transmission matrix enables not only correcting distortions but also harnessing these effects for creating a confidential data connection between legitimate communication parties, Alice and Bob. The feasibility of this physical-layer-security-based approach is demonstrated experimentally for the first time on a multimode fiber link to which the eavesdropper Eve is physically coupled. Once the proper structured light field is launched at Alice's side, the message can be delivered to Bob, and, simultaneously, the decipherment for an illegitimate wiretapper Eve is destroyed. Within a real communication scenario, we implement wiretap codes and demonstrate confidentiality by quantifying the level of secrecy. Compared to an uncoded data transmission, the amount of securely exchanged data is enhanced by a factor of 538. The complex light transportation phenomena that have long been considered limiting and have restricted the widespread use of multimode fiber are exploited for opening new perspectives on information security in spatial multiplexing communication systems. © 2022, CC BY.

关键词： Multimode fibers

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