Development of Flexible Biceps Tremors Sensing Chip of PVDF Fibers with Nano-Silver Particles by Near-Field Electrospinning

Polyvinylidene fluoride (PVDF) and AgNO3/PVDF composite piezoelectric fibers were prepared using near-field electrospinning technology. The prepared fibers are attached to the electrode sheet and encapsulated with polydimethylsiloxane to create an energy acquisition device and further fabricated into a dynamic sensing element. The addition of AgNO3 significantly increased the conductivity of the solution from 40.33 μS/cm to 883.59 μS/cm, which in turn made the fiber drawing condition smoother with the increase of high voltage electric field and reduced the fiber wire diameter size from 0.37 μm to 0.23 μm. The tapping test shows that the voltage signal can reach ~0.9 V at a frequency of 7 Hz, and the energy conversion efficiency is twice that of the PVDF output voltage. The addition of AgNO3 effectively enhances the molecular bonding ability, which effectively increases the piezoelectric constants of PVDF piezoelectric fibers. When the human body is exercised for a long period of time and the body is overloaded, the biceps muscle is found to produce 8 to 16 tremors/second through five arm flexion movements. The voltage output of the flexible dynamic soft sensor is between 0.7–0.9 V and shows an orderly alternating current waveform of voltage signals. The sensor can be used to detect muscle tremors after high-intensity training and to obtain advance information about changes in the symptoms of fasciculation, allowing for more accurate diagnosis and treatment.

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Dynamical Peculiarities of Concatenational Changes in Functional Cardiovascular Parameters

Baltic Journal of Sport and Health Sciences ◽

10.33607/bjshs.v3i82.322 ◽

2018 ◽

Vol 3 (82) ◽

Author(s):

Eurelija Venskaitytė ◽

Jonas Poderys ◽

Tadas Česnaitis

Keyword(s):

Time Series ◽

Time Series Analysis ◽

Functional State ◽

The Body ◽

Functional Changes ◽

High Intensity Training ◽

Series Analysis ◽

Greco Roman ◽

St Segment ◽

Standard Lead

Research background and hypothesis. Traditional time series analysis techniques, which are also used for the analysis of cardiovascular signals, do not reveal the relationship between the changes in the indices recorded associated with the multiscale and chaotic structure of the tested object, which allows establishing short-and long-term structural and functional changes.Research aim was to reveal the dynamical peculiarities of interactions of cardiovascular system indices while evaluating the functional state of track-and-field athletes and Greco-Roman wrestlers.Research methods. Twenty two subjects participated in the study, their average age of 23.5 ± 1.7 years. During the study standard 12 lead electrocardiograms (ECG) were recorded. The following ECG parameters were used in the study: duration of RR interval taken from the II standard lead, duration of QRS complex, duration of JT interval and amplitude of ST segment taken from the V standard lead.Research results. Significant differences were found between inter-parametric connections of ST segment amplitude and JT interval duration at the pre and post-training testing. Observed changes at different hierarchical levels of the body systems revealed inadequate cardiac metabolic processes, leading to changes in the metabolic rate of the myocardium and reflected in the dynamics of all investigated interactions.Discussion and conclusions. It has been found that peculiarities of the interactions of ECG indices interactions show the exposure of the functional changes in the body at the onset of the workload. The alterations of the functional state of the body and the signs of fatigue, after athletes performed two high intensity training sessions per day, can be assessed using the approach of the evaluation of interactions between functional variables. Therefore the evaluation of the interactions of physiological signals by using time series analysis methods is suitable for the observation of these processes and the functional state of the body.Keywords: electrocardiogram, time series, functional state.

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Investigation on Wireless Link for Medical Telemetry Including Impedance Matching of Implanted Antennas

Sensors ◽

10.3390/s21041431 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1431

Author(s):

Ilkyu Kim ◽

Sun-Gyu Lee ◽

Yong-Hyun Nam ◽

Jeong-Hae Lee

Keyword(s):

Real Time ◽

Human Body ◽

Near Field ◽

Impedance Matching ◽

The Body ◽

Field Pattern ◽

Communication Link ◽

Far Field ◽

Antenna Coupling ◽

Medical Telemetry

The development of biomedical devices benefits patients by offering real-time healthcare. In particular, pacemakers have gained a great deal of attention because they offer opportunities for monitoring the patient’s vitals and biological statics in real time. One of the important factors in realizing real-time body-centric sensing is to establish a robust wireless communication link among the medical devices. In this paper, radio transmission and the optimal characteristics for impedance matching the medical telemetry of an implant are investigated. For radio transmission, an integral coupling formula based on 3D vector far-field patterns was firstly applied to compute the antenna coupling between two antennas placed inside and outside of the body. The formula provides the capability for computing the antenna coupling in the near-field and far-field region. In order to include the effects of human implantation, the far-field pattern was characterized taking into account a sphere enclosing an antenna made of human tissue. Furthermore, the characteristics of impedance matching inside the human body were studied by means of inherent wave impedances of electrical and magnetic dipoles. Here, we demonstrate that the implantation of a magnetic dipole is advantageous because it provides similar impedance characteristics to those of the human body.

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Biomimetic tough helicoidally structured material through novel electrospinning based additive manufacturing

MRS Advances ◽

10.1557/adv.2019.313 ◽

2019 ◽

Vol 4 (43) ◽

pp. 2345-2354 ◽

Cited By ~ 2

Author(s):

Komal Agarwal ◽

Rahul Sahay ◽

Avinash Baji ◽

Arief S. Budiman

Keyword(s):

Structural Design ◽

Polyvinylidene Fluoride ◽

Architectural Design ◽

Mechanical Characteristics ◽

Near Field ◽

Structural Materials ◽

Electrospinning Technique ◽

Mantis Shrimp ◽

Novel Method ◽

Microstructural Design

ABSTRACTNatural structural materials (NSMs) such as nacre, teeth, bones and crustacean exoskeleton are usually made of weak biomaterials arranged in specific structural design imparting them remarkable mechanical characteristics. Such hierarchical structural layouts found in nature encourage designing of mechanically desirable synthetic structural materials (SSMs). Among variety of natural hierarchical layouts, this paper specifically focuses on helicoidal architectural design found in the tough dactyl club of mantis shrimp. We first decode the mechanics behind helicoidal microstructural design and document the development of impact resistant macroscale helicoidal architectured synthetic structural materials (HA-SSMs). Next, near-field electrospinning technique (NFES)- both melt (polycaprolactone) and solution (polyvinylidene fluoride) type has been discussed in detail, as a novel method for developing lab scale 3D biomimetic HA-SSMs in micro-nanoscale. Further, the effect of the helical arrangement, size of substructures and surface treatment on strength and toughness of NFES fabricated HA-SSMs samples is analysed.

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Validation of the Index to Determine Design Parameters of a WEC for the Cost Optimization of a Wave Farm

Volume 9: Ocean Renewable Energy ◽

10.1115/omae2015-41908 ◽

2015 ◽

Author(s):

Takashi Okamoto ◽

Yutaro Fukaya ◽

Yasushi Higo

Keyword(s):

Cost Optimization ◽

Energy Conversion Efficiency ◽

The Body ◽

Farm Size ◽

Design Parameters ◽

Parameter Combination ◽

Index Value ◽

The Cost ◽

Validation Tests ◽

Wave Farm

An index to estimate the cost of electricity (COE) generated by a wave farm from the design parameters of a wave energy converter (WEC), such as the body size and the generator capacity, was examined to show the validity of index value in this study. The validation tests are performed for three different wave farm settings at three different locations. The result displays the potential of index to capture the trend of COE value especially when the wave farm size is small. The calculation result of COE reveals that the parameter combination to give better profitability is determined by the balance between WEC construction fee and installation fee. So, it would be different from the optimum size to have the best energy conversion efficiency. It also explains the shift of parameter combination to give the better profitability when the size of wave farm is changed. However, the index contains certain level of error because of the lack of this feature. Therefore, the error becomes larger when the size of wave farm becomes larger. As a result, it was found that the modification of the index is needed to improve the accuracy by including the cost related to the number of buoys in the wave farm.

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A Micro-Force-Tracking System Based on PVDF Static Micro-Force Sensor and Fuzzy-PID Control Method

Advanced Engineering Forum ◽

10.4028/www.scientific.net/aef.2-3.489 ◽

2011 ◽

Vol 2-3 ◽

pp. 489-494

Author(s):

Zhi Yong Sun ◽

Wen Lin Chen ◽

Yun Quan Su ◽

Li Na Hao

Keyword(s):

Pid Control ◽

Polyvinylidene Fluoride ◽

Control Method ◽

Tracking System ◽

Force Sensor ◽

Fuzzy Pid ◽

Sensing Element ◽

Fuzzy Pid Control ◽

Force Tracking ◽

Micro Force Sensor

This article is intended to design a static micro-force sensor with a simple structure employing the polymer material PVDF (polyvinylidene fluoride) film as its sensing element, and will carry out some micro-force tracking tests. During the tracking tests, this paper employs a Fuzzy-PID control method and an ordinary PD control method to control the system, and will also analyze the results of them.

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Numerical Study on the Feasibility of a 24 GHz ISM-Band Doppler Radar Antenna for Near-Field Sensing of Human Respiration in Electromagnetic Aspects

Applied Sciences ◽

10.3390/app10186159 ◽

2020 ◽

Vol 10 (18) ◽

pp. 6159 ◽

Cited By ~ 1

Author(s):

Seungyong Park ◽

Sungpeel Kim ◽

Dong Kyoo Kim ◽

Jaehoon Choi ◽

Kyung-Young Jung

Keyword(s):

Human Body ◽

Doppler Radar ◽

Numerical Study ◽

Near Field ◽

The Body ◽

Ism Band ◽

Human Respiration ◽

Field Sensing ◽

Radar Antenna ◽

24 Ghz

The feasibility study of a 24 GHz industrial, scientific, and medical (ISM) band Doppler radar antenna in electromagnetic aspects is numerically performed for near-field sensing of human respiration. The Doppler radar antenna consists of a transmitting (Tx) antenna and a receiving (Rx) antenna close to the human body for a wearable device. The designed slot-type Doppler radar antenna is embedded between an RO4350B superstrate and an FR-4 substrate. To obtain the higher radiation pattern of the antenna towards the human body, a ground plane reflector is placed underneath the substrate. The measured −10 dB reflection coefficient (S11) bandwidth is 23.74 to 25.56 GHz and the mutual coupling (S21) between Tx and Rx antennas is lower than −30 dB at target frequencies. The Doppler radar performance of the proposed Doppler radar antenna is performed numerically by investigating the signal returned from the human body. The Doppler effect due to human respiration is investigated through the I/Q and arctangent demodulation of the returned signal. According to the results, the phase variation of the returned signal is proportional to the displacement of the body surface, which is about 0.8 rad in accordance with 1 mm displacement. The numerical experiments indicate that the proposed Doppler radar antenna can be used for near-field sensing of human respiration in electromagnetic aspects.

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Polyvinylidene Fluoride-Added Ceramic Powder Composite Near-Field Electrospinned Piezoelectric Fiber-Based Low-Frequency Dynamic Sensors

ACS Omega ◽

10.1021/acsomega.0c00805 ◽

2020 ◽

Vol 5 (28) ◽

pp. 17090-17101

Author(s):

Cheng-Tang Pan ◽

Shao-Yu Wang ◽

Chung-Kun Yen ◽

Ajay Kumar ◽

Shiao-Wei Kuo ◽

...

Keyword(s):

Polyvinylidene Fluoride ◽

Near Field ◽

Ceramic Powder ◽

Low Frequency ◽

Powder Composite ◽

Piezoelectric Fiber

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Experimental validation of a polyvinylidene fluoride sensing element in a tactile sensor

2010 Annual International Conference of the IEEE Engineering in Medicine and Biology ◽

10.1109/iembs.2010.5627847 ◽

2010 ◽

Cited By ~ 1

Author(s):

S Yahud ◽

S Dokos ◽

J W Morley ◽

N H Lovell

Keyword(s):

Polyvinylidene Fluoride ◽

Experimental Validation ◽

Tactile Sensor ◽

Sensing Element ◽

Fluoride Sensing

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Finger-Mounted Tactile Sensor for Evaluating Surfaces

Journal of Robotics and Mechatronics ◽

10.20965/jrm.2012.p0430 ◽

2012 ◽

Vol 24 (3) ◽

pp. 430-440 ◽

Cited By ~ 4

Author(s):

Ryo Kikuuwe ◽

◽

Kenta Nakamura ◽

Motoji Yamamoto

Keyword(s):

Polyvinylidene Fluoride ◽

Tactile Sensor ◽

Pvdf Film ◽

Signal Sequences ◽

Film Sensor ◽

Hand Motion ◽

Textile Fabrics ◽

Thin Structure ◽

Voltage Signal ◽

Area Expansion

This paper presents a finger-mounted tactile sensor for extracting information on fine surface properties of objects such as textile fabrics. The prototype sensor has a thin structure composed of a sheet of PVDF (polyvinylidene fluoride) film sensor and some metal parts for converting compressive forces into area expansion of the PVDF film. By using a signal processing program based on the FFT (fast Fourier transform), voltage signal sequences from nine different fabrics were distinguished, even in the presence of variations in the pressing force and the speed of rubbing motion induced by the fluctuations in the user’s hand motion. In addition, the signal sequences from abraded fabrics were sorted by their levels of abrasion by extracting a signal component correlated with the abrasion level.11. This paper is the full translation from the transactions of JSME, Series C, Vol.77, No.784, 2011.

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