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801 KiB

Open AccessArticle

E-textiles in Clinical Rehabilitation: A Scoping Review

by Amanda Fleury, Maddy Sugar and Tom Chau

Electronics 2015, 4(1), 173-203; https://doi.org/10.3390/electronics4010173 - 25 Feb 2015

Cited by 52 | Viewed by 11855

Abstract

Electronic textiles have potential for many practical uses in clinical rehabilitation. This scoping review appraises recent and emerging developments of textile-based sensors with applications to rehabilitation. Contributions published from 2009 to 2013 are appraised with a specific focus on the measured physiological or [...] Read more.

Electronic textiles have potential for many practical uses in clinical rehabilitation. This scoping review appraises recent and emerging developments of textile-based sensors with applications to rehabilitation. Contributions published from 2009 to 2013 are appraised with a specific focus on the measured physiological or biomechanical phenomenon, current measurement practices, textile innovations, and their merits and limitations. While fabric-based signal quality and sensor integration have advanced considerably, overall system integration (including circuitry and power) has not been fully realized. Validation against clinical gold standards is inconsistent at best, and feasibility with clinical populations remains to be demonstrated. The overwhelming focus of research and development has been on remote sensing but the opportunity for textile-mediated feedback to the wearer remains unexplored. Recommendations for future research are provided. Full article

(This article belongs to the Special Issue Wearable Electronics)

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5801 KiB

Open AccessArticle

The Diabetes Assistant: A Smartphone-Based System for Real-Time Control of Blood Glucose

by Patrick Keith-Hynes, Benton Mize, Antoine Robert and Jérôme Place

Electronics 2014, 3(4), 609-623; https://doi.org/10.3390/electronics3040609 - 14 Nov 2014

Cited by 62 | Viewed by 12018

Abstract

Type 1 Diabetes Mellitus (T1DM) is an autoimmune disease in which the insulin-producing beta cells of the pancreas are destroyed and insulin must be injected daily to enable the body to metabolize glucose. Standard therapy for T1DM involves self-monitoring of blood glucose (SMBG) [...] Read more.

Type 1 Diabetes Mellitus (T1DM) is an autoimmune disease in which the insulin-producing beta cells of the pancreas are destroyed and insulin must be injected daily to enable the body to metabolize glucose. Standard therapy for T1DM involves self-monitoring of blood glucose (SMBG) several times daily with a blood glucose meter and injecting insulin via a syringe, pen or insulin pump. An “Artificial Pancreas” (AP) is a closed-loop control system that uses a continuous glucose monitor (CGM), an insulin pump and an internal algorithm to automatically manage insulin infusion to keep the subject’s blood glucose within a desired range. Although no fully closed-loop AP systems are currently commercially available there are intense academic and commercial efforts to produce safe and effective AP systems. In this paper we present the Diabetes Assistant (DiAs), an ultraportable AP research platform designed to enable home studies of Closed Loop Control (CLC) of blood glucose in subjects with Type 1 Diabetes Mellitus. DiAs consists of an Android (Google Inc., Mountain View, CA, USA) smartphone equipped with communication, control and user interface software wirelessly connected to a continuous glucose monitor and insulin pump. The software consists of a network of mobile applications with well-defined Application Programming Interfaces (APIs) running atop an enhanced version of Android with non-essential elements removed. CLC and safety applications receive real-time data from the CGM and pump, estimate the patient’s metabolic state and risk of hypo- and hyperglycemia, adjust the insulin infusion rate, raise alarms as needed and transmit de-identified data to a secure remote server. Some applications may be replaced by researchers wishing to conduct outpatient ambulatory studies of novel Closed Loop Control, Safety or User Interface modules. Over the past three years the DiAs platform has been used in a series of AP clinical trials sponsored by the National Institutes of Health, the Juvenile Diabetes Research Foundation, the Helmsley Charitable Trust and the European Union AP@Home project. Results of clinical trials using DiAs indicate that a smartphone with targeted operating system modifications and appropriate system software can be successfully used in outpatient clinical trials of FDA Class III medical devices such as Artificial Pancreas. Full article

(This article belongs to the Special Issue Wearable Electronics)

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1709 KiB

Open AccessArticle

Garment-Integrated Bend Sensor

by Guido Gioberto and Lucy E. Dunne

Electronics 2014, 3(4), 564-581; https://doi.org/10.3390/electronics3040564 - 26 Sep 2014

Cited by 6 | Viewed by 7363

Abstract

Garment-integrated sensors equip clothes with a smart sensing capability, while preserving the comfort of the user. However, this benefit can be to the detriment of sensing accuracy due to the unpredictability of garment movement (which affects sensor positioning) and textile folds (which can [...] Read more.

Garment-integrated sensors equip clothes with a smart sensing capability, while preserving the comfort of the user. However, this benefit can be to the detriment of sensing accuracy due to the unpredictability of garment movement (which affects sensor positioning) and textile folds (which can affect sensor orientation). However, sensors integrated directly into garments or fabric structures can also be used to detect the movement of the garment during wearing. Specifically, a textile bend sensor could be used to sense folds in the garment. We tested a garment-integrated stitched sensor for five types of folds, stitched on five different weights of un-stretchable denim fabric and analyzed the effects of fold complexity and fabric stiffness, under un-insulated and insulated conditions. Results show that insulation improves the linearity and repeatability of the sensor response, particularly for higher fold complexity. Stiffer fabrics show greater sensitivity, but less linearity. Sensor response amplitude is larger for more complex fold geometries. The utility of a linear bending response (insulated) and a binary shorting response (un-insulated) is discussed. Overall, the sensor exhibits excellent repeatability and accuracy, particularly for a fiber-based, textile-integrated sensor. Full article

(This article belongs to the Special Issue Wearable Electronics)

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1268 KiB

Open AccessArticle

Investigation of a Switchable Textile Communication System on the Human Body

by Qiang Bai, Srijittra Swaisaenyakorn, Hyung-Joo Lee, Kenneth L. Ford, John C. Batchelor and Richard J. Langley

Electronics 2014, 3(3), 491-503; https://doi.org/10.3390/electronics3030491 - 18 Aug 2014

Cited by 8 | Viewed by 7131

Abstract

In this paper, a switchable textile communication system working at 2.45 GHz ISM band is presented and studied for different locations within a realistic on-body environment. A 3D laser scanner is used to generate a numerical phantom of the measured subject to improve [...] Read more.

In this paper, a switchable textile communication system working at 2.45 GHz ISM band is presented and studied for different locations within a realistic on-body environment. A 3D laser scanner is used to generate a numerical phantom of the measured subject to improve the accuracy of the simulations which are carried out for different body postures. For the off-body communications, the system is acting as an aperture coupled microstrip patch antenna with a boresight gain of 1.48 dBi. On-body communication is achieved by using a textile stripline, which gives approximately 5 dB transmission loss over 600 mm distance. The system is switched between on and off-body modes by PIN diodes. Common issues, such as shape distortion and body detuning effects which the textile antenna may experience in realistic use are fully discussed. Robust antenna performance is noted in the on-body tests, and an additional 3 dB transmission coefficient deduction was noticed in the most severe shape distortion case. Full article

(This article belongs to the Special Issue Wearable Electronics)

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1196 KiB

Open AccessArticle

Radiation Pattern Measurement of a Low-Profile Wearable Antenna Using an Optical Fibre and a Solid Anthropomorphic Phantom

by Tian Hong Loh, David Cheadle and Lawrence Rosenfeld

Electronics 2014, 3(3), 462-473; https://doi.org/10.3390/electronics3030462 - 5 Aug 2014

Cited by 8 | Viewed by 9251

Abstract

This paper presents a study into radiation pattern measurements of an electrically small dielectric resonator antenna (DRA) operating between 2.4 and 2.5 GHz in the industrial, scientific and medical (ISM) radio band for body-centric wireless communication applications. To eliminate the distortion of the [...] Read more.

This paper presents a study into radiation pattern measurements of an electrically small dielectric resonator antenna (DRA) operating between 2.4 and 2.5 GHz in the industrial, scientific and medical (ISM) radio band for body-centric wireless communication applications. To eliminate the distortion of the radiation pattern associated with the unwanted radiation from a metallic coaxial cable feeding the antenna we have replaced it with a fibre optic feed and an electro-optical (EO) transducer. The optical signal is then converted back to RF using an Opto-Electric Field Sensor (OEFS) system. To ensure traceable measurements of the radiation pattern performance of the wearable antenna a generic head and torso solid anthropomorphic phantom model has been employed. Furthermore, to illustrate the benefits of the method, numerical simulations of the co-polar and cross-polar H-plane radiation patterns at 2.4, 2.45, and 2.5 GHz are compared with the measured results obtained using: (i) an optical fibre; and (ii) a metallic coaxial cable. Full article

(This article belongs to the Special Issue Wearable Electronics)

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362 KiB

Open AccessArticle

A Low Latency Electrocardiographic QRS Activity Recovery Technique for Use on the Upper Left Arm

by William D. Lynn, Omar J. Escalona and David J. McEneaney

Electronics 2014, 3(3), 409-418; https://doi.org/10.3390/electronics3030409 - 16 Jul 2014

Cited by 5 | Viewed by 5497

Abstract

Empirical mode decomposition is used as a low latency method of recovering the cardiac ventricular activity QRS biopotential signals recorded from the upper arm. The recovery technique is tested and compared with the industry accepted technique of signal averaging using a database of [...] Read more.

Empirical mode decomposition is used as a low latency method of recovering the cardiac ventricular activity QRS biopotential signals recorded from the upper arm. The recovery technique is tested and compared with the industry accepted technique of signal averaging using a database of “normal” rhythm traces from bipolar ECG leads along the left arm, recorded from patient volunteers at a cardiology day procedure clinic. The same partial recomposition technique is applied to recordings taken using an innovative dry electrode technology supplied by Plessey Semiconductors. In each case, signal to noise ratio (SNR) is used as a metric for comparison. Full article

(This article belongs to the Special Issue Wearable Electronics)

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686 KiB

Open AccessArticle

SmartStep: A Fully Integrated, Low-Power Insole Monitor

by Nagaraj Hegde and Edward Sazonov

Electronics 2014, 3(2), 381-397; https://doi.org/10.3390/electronics3020381 - 18 Jun 2014

Cited by 41 | Viewed by 11592

Abstract

Shoe-mounted wearable sensors can be used in applications, such as activity monitoring, gait analysis, post-stroke rehabilitation, body weight measurements and energy expenditure studies. Such wearable sensors typically require the modification or alteration of the shoe, which is not typically feasible for large populations [...] Read more.

Shoe-mounted wearable sensors can be used in applications, such as activity monitoring, gait analysis, post-stroke rehabilitation, body weight measurements and energy expenditure studies. Such wearable sensors typically require the modification or alteration of the shoe, which is not typically feasible for large populations without the direct involvement of shoe manufacturers. This article presents an insole-based wearable sensor (SmartStep) that has its electronics fully embedded into a generic insole, which is usable with a large variety of shoes and, thus, resolves the need for shoe modification. The SmartStep is an always-on electronic device that comprises a 3D accelerometer, a 3D gyroscope and resistive pressure sensors implemented around a CC2540 system-on-chip with an 8051 processor core, Bluetooth low energy (BLE) connectivity and flash memory buffer. The SmartStep is wirelessly interfaced to an Android smart phone application with data logging and visualization capabilities. This article focuses on low-power implementation methods and on the method developed for reliable data buffering, alleviating intermittent connectivity resulting from the user leaving the vicinity of the smart phone. The conducted tests illustrate the power consumption for several possible usage scenarios and the reliability of the data retention method. The trade-off between the power consumption and supported functionality is discussed, demonstrating that SmartStep can be worn for more than two days between battery recharges. The results of the mechanical reliability test on the SmartStep indicate that the pressure sensors in the SmartStep tolerated prolonged human wear. The SmartStep system collected more than 98.5% of the sensor data, in real usage scenarios, having intermittent connectivity with the smart phone. Full article

(This article belongs to the Special Issue Wearable Electronics)

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1148 KiB

Open AccessArticle

Footwear and Wrist Communication Links using 2.4 GHz and UWB Antennas

by Domenico Gaetano, Patrick McEvoy, Max J. Ammann, Colm Brannigan, Louise Keating and Frances Horgan

Electronics 2014, 3(2), 339-350; https://doi.org/10.3390/electronics3020339 - 4 Jun 2014

Cited by 5 | Viewed by 7936

Abstract

It is reported that wearable electronic devices are to be used extensively in the next generation of sensors for sports and health monitoring. The information obtained from sensors on the human body depends on the biological parameters, the measurement rate and the number [...] Read more.

It is reported that wearable electronic devices are to be used extensively in the next generation of sensors for sports and health monitoring. The information obtained from sensors on the human body depends on the biological parameters, the measurement rate and the number of sensors. The choice of the wireless protocol depends on the required data rates and on system configurations. The communication link quality is achieved with narrowband technologies such as Bluetooth or Zigbee, provided that the number of sensors is small and data rates are low. However, real-time measurements using wideband channels may also be necessary. This paper reports narrowband link performance at 2.45 GHz for comparison with two UWB channels centered at 3.95 GHz and 7.25 GHz. A monopole antenna covering 2.45 GHz and UWB is optimized for an on-body communication link between the footwear and the wrist. The cumulative distribution function of several path loss measurements is reported and compared for a subject standing and walking. Results show that the larger bandwidth in the UWB channel reduces fading and stabilizes the channel predictability. Full article

(This article belongs to the Special Issue Wearable Electronics)

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1787 KiB

Open AccessArticle

End-Fire Antenna for BAN at 60 GHz: Impact of Bending, On-Body Performances, and Study of an On to Off-Body Scenario

by Anda R. Guraliuc, Nacer Chahat, Carole Leduc, Maxim Zhadobov and Ronan Sauleau

Electronics 2014, 3(2), 221-233; https://doi.org/10.3390/electronics3020221 - 8 Apr 2014

Cited by 16 | Viewed by 10430

Abstract

A compact end-fire wearable Yagi-Uda antenna covering the entire 57–64 GHz frequency band is characterized in free space, in the presence of a skin-equivalent phantom and under bending conditions. The results demonstrate that, when placed on the body and/or bended, the antenna preserves [...] Read more.

A compact end-fire wearable Yagi-Uda antenna covering the entire 57–64 GHz frequency band is characterized in free space, in the presence of a skin-equivalent phantom and under bending conditions. The results demonstrate that, when placed on the body and/or bended, the antenna preserves satisfactory performances. The possibility of its use for an on/off-body communications at 60 GHz is investigated numerically and experimentally in a representative scenario in terms of E-field and power flow distributions, as well as in terms of path gain. It is shown that this antenna is a suitable candidate for high-data-rate short-range on/off-body transmissions. Full article

(This article belongs to the Special Issue Wearable Electronics)

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888 KiB

Open AccessArticle

Use of a Wireless Network of Accelerometers for Improved Measurement of Human Energy Expenditure

by Alexander H. Montoye, Bo Dong, Subir Biswas and Karin A. Pfeiffer

Electronics 2014, 3(2), 205-220; https://doi.org/10.3390/electronics3020205 - 3 Apr 2014

Cited by 12 | Viewed by 7008

Abstract

Single, hip-mounted accelerometers can provide accurate measurements of energy expenditure (EE) in some settings, but are unable to accurately estimate the energy cost of many non-ambulatory activities. A multi-sensor network may be able to overcome the limitations of a single accelerometer. Thus, the [...] Read more.

Single, hip-mounted accelerometers can provide accurate measurements of energy expenditure (EE) in some settings, but are unable to accurately estimate the energy cost of many non-ambulatory activities. A multi-sensor network may be able to overcome the limitations of a single accelerometer. Thus, the purpose of our study was to compare the abilities of a wireless network of accelerometers and a hip-mounted accelerometer for the prediction of EE. Thirty adult participants engaged in 14 different sedentary, ambulatory, lifestyle and exercise activities for five minutes each while wearing a portable metabolic analyzer, a hip-mounted accelerometer (AG) and a wireless network of three accelerometers (WN) worn on the right wrist, thigh and ankle. Artificial neural networks (ANNs) were created separately for the AG and WN for the EE prediction. Pearson correlations (r) and the root mean square error (RMSE) were calculated to compare criterion-measured EE to predicted EE from the ANNs. Overall, correlations were higher (r = 0.95 vs. r = 0.88, p < 0.0001) and RMSE was lower (1.34 vs. 1.97 metabolic equivalents (METs), p < 0.0001) for the WN than the AG. In conclusion, the WN outperformed the AG for measuring EE, providing evidence that the WN can provide highly accurate estimates of EE in adults participating in a wide range of activities. Full article

(This article belongs to the Special Issue Wearable Electronics)

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1126 KiB

Open AccessArticle

Laboratory Validation of Inertial Body Sensors to Detect Cigarette Smoking Arm Movements

by Bethany R. Raiff, Çağdaş Karataş, Erin A. McClure, Dario Pompili and Theodore A. Walls

Electronics 2014, 3(1), 87-110; https://doi.org/10.3390/electronics3010087 - 27 Feb 2014

Cited by 24 | Viewed by 8017

Abstract

Cigarette smoking remains the leading cause of preventable death in the United States. Traditional in-clinic cessation interventions may fail to intervene and interrupt the rapid progression to relapse that typically occurs following a quit attempt. The ability to detect actual smoking behavior in [...] Read more.

Cigarette smoking remains the leading cause of preventable death in the United States. Traditional in-clinic cessation interventions may fail to intervene and interrupt the rapid progression to relapse that typically occurs following a quit attempt. The ability to detect actual smoking behavior in real-time is a measurement challenge for health behavior research and intervention. The successful detection of real-time smoking through mobile health (mHealth) methodology has substantial implications for developing highly efficacious treatment interventions. The current study was aimed at further developing and testing the ability of inertial sensors to detect cigarette smoking arm movements among smokers. The current study involved four smokers who smoked six cigarettes each in a laboratory-based assessment. Participants were outfitted with four inertial body movement sensors on the arms, which were used to detect smoking events at two levels: the puff level and the cigarette level. Two different algorithms (Support Vector Machines (SVM) and Edge-Detection based learning) were trained to detect the features of arm movement sequences transmitted by the sensors that corresponded with each level. The results showed that performance of the SVM algorithm at the cigarette level exceeded detection at the individual puff level, with low rates of false positive puff detection. The current study is the second in a line of programmatic research demonstrating the proof-of-concept for sensor-based tracking of smoking, based on movements of the arm and wrist. This study demonstrates efficacy in a real-world clinical inpatient setting and is the first to provide a detection rate against direct observation, enabling calculation of true and false positive rates. The study results indicate that the approach performs very well with some participants, whereas some challenges remain with participants who generate more frequent non-smoking movements near the face. Future work may allow for tracking smoking in real-world environments, which would facilitate developing more effective, just-in-time smoking cessation interventions. Full article

(This article belongs to the Special Issue Wearable Electronics)

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933 KiB

Open AccessArticle

Experimental Investigation of Subject-Specific On-Body Radio Propagation Channels for Body-Centric Wireless Communications

by Mohammad Monirujjaman Khan, Qammer Hussain Abbasi, Akram Alomainy and Clive Parini

Electronics 2014, 3(1), 26-42; https://doi.org/10.3390/electronics3010026 - 28 Jan 2014

Cited by 10 | Viewed by 8831

Abstract

In this paper, subject-specific narrowband (2.45 GHz) and ultra-wideband (3–10.6 GHz) on-body radio propagation studies in wireless body area networks (WBANs) were performed by characterizing the path loss for eight different human subjects of different shapes and sizes. The body shapes and sizes [...] Read more.

In this paper, subject-specific narrowband (2.45 GHz) and ultra-wideband (3–10.6 GHz) on-body radio propagation studies in wireless body area networks (WBANs) were performed by characterizing the path loss for eight different human subjects of different shapes and sizes. The body shapes and sizes of the test subjects used in this study are characterised as thin, medium build, fatty, shorter, average height and taller. Experimental investigation was made in an indoor environment using a pair of printed monopoles (for the narrowband case) and a pair of tapered slot antennas (for the ultra-wideband (UWB) case). Results demonstrated that, due to the different sizes, heights and shapes of the test subjects, the path loss exponent value varies up to maximum of 0.85 for the narrowband on-body case, whereas a maximum variation of the path loss exponent value of 1.15 is noticed for the UWB case. In addition, the subject-specific behaviour of the on-body radio propagation channels was compared between narrowband and UWB systems, and it was deduced that the on-body radio channels are subject-specific for both narrowband and UWB system cases, when the same antennas (same characteristics) are used. The effect of the human body shape and size variations on the eight different on-body radio channels is also studied for both the narrowband and UWB cases. Full article

(This article belongs to the Special Issue Wearable Electronics)

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Review

Jump to: Research

4974 KiB

Open AccessReview

Wearable Wireless Cardiovascular Monitoring Using Textile-Based Nanosensor and Nanomaterial Systems

by Prashanth Shyamkumar, Pratyush Rai, Sechang Oh, Mouli Ramasamy, Robert E. Harbaugh and Vijay Varadan

Electronics 2014, 3(3), 504-520; https://doi.org/10.3390/electronics3030504 - 19 Aug 2014

Cited by 59 | Viewed by 17325

Abstract

Wearable and ultraportable electronics coupled with pervasive computing are poised to revolutionize healthcare services delivery. The potential cost savings in both treatment, as well as preventive care are the focus of several research efforts across the globe. In this review, we describe the [...] Read more.

Wearable and ultraportable electronics coupled with pervasive computing are poised to revolutionize healthcare services delivery. The potential cost savings in both treatment, as well as preventive care are the focus of several research efforts across the globe. In this review, we describe the motivations behind wearable solutions to real-time cardiovascular monitoring from a perspective of current healthcare services, as well as from a systems design perspective. We identify areas where emerging research is underway, namely: nanotechnology in textile-based wearable monitors and healthcare solutions targeted towards smart devices, like smartphones and tablets. Full article

(This article belongs to the Special Issue Wearable Electronics)

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2398 KiB

Open AccessReview

Compact, Wearable Antennas for Battery-Less Systems Exploiting Fabrics and Magneto-Dielectric Materials

by Alessandra Costanzo, Diego Masotti and Martino Aldrigo

Electronics 2014, 3(3), 474-490; https://doi.org/10.3390/electronics3030474 - 18 Aug 2014

Cited by 9 | Viewed by 11201

Abstract

In this paper, we describe some promising solutions to the modern need for wearable, energy-aware, miniaturized, wireless systems, whose typical envisaged application is a body area network (BAN). To reach this goal, novel materials are adopted, such as fabrics, in place of standard [...] Read more.

In this paper, we describe some promising solutions to the modern need for wearable, energy-aware, miniaturized, wireless systems, whose typical envisaged application is a body area network (BAN). To reach this goal, novel materials are adopted, such as fabrics, in place of standard substrates and metallizations, which require a systematic procedure for their electromagnetic characterization. Indeed, the design of such sub-systems represents a big issue, since approximate approaches could result in strong deviations from the actual system performance. To face this problem, we demonstrate our design procedure, which is based on the concurrent use of electromagnetic software tools and nonlinear circuit-level techniques, able to simultaneously predict the actual system behavior of an antenna system, consisting of the radiating and of the nonlinear blocks, at the component level. This approach is demonstrated for the design of a fully-wearable tri-band rectifying antenna (rectenna) and of a button-shaped, electrically-small antenna deploying a novel magneto-dielectric substrate. Simulations are supported by measurements, both in terms of antenna port parameters and far-field results. Full article

(This article belongs to the Special Issue Wearable Electronics)

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1303 KiB

Open AccessReview

A Compact Dual-Mode Wearable Antenna for Body-Centric Wireless Communications

by Chia-Hsien Lin and Koichi Ito

Electronics 2014, 3(3), 398-408; https://doi.org/10.3390/electronics3030398 - 1 Jul 2014

Cited by 10 | Viewed by 8192

Abstract

The miniaturization of electronic devices is leading to the creation of body-centric wireless communications (BCWCs), in which wireless devices are attached to the human body. In particular, personal healthcare is considered as the biggest potential application. In this paper, we propose a compact [...] Read more.

The miniaturization of electronic devices is leading to the creation of body-centric wireless communications (BCWCs), in which wireless devices are attached to the human body. In particular, personal healthcare is considered as the biggest potential application. In this paper, we propose a compact wearable dual-mode (on-body and off-body modes) antenna for personal healthcare systems. For on-body mode at 10 MHz, received voltages are analyzed with a chest phantom, while for the off-body mode in the 2.4 GHz ISM band, reflection coefficient (S₁₁) and radiation patterns are studied. Full article

(This article belongs to the Special Issue Wearable Electronics)

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1692 KiB

Open AccessReview

Embroidery and Related Manufacturing Techniques for Wearable Antennas: Challenges and Opportunities

by Aris Tsolis, William G. Whittow, Antonis A. Alexandridis and J. C. Vardaxoglou

Electronics 2014, 3(2), 314-338; https://doi.org/10.3390/electronics3020314 - 30 May 2014

Cited by 209 | Viewed by 24209

Abstract

This paper will review the evolution of wearable textile antennas over the last couple of decades. Particular emphasis will be given to the process of embroidery. This technique is advantageous for the following reasons: (i) bespoke or mass produced designs can be manufactured [...] Read more.

This paper will review the evolution of wearable textile antennas over the last couple of decades. Particular emphasis will be given to the process of embroidery. This technique is advantageous for the following reasons: (i) bespoke or mass produced designs can be manufactured using digitized embroidery machines; (ii) glue is not required and (iii) the designs are aesthetic and are integrated into clothing rather than being attached to it. The embroidery technique will be compared to alternative manufacturing processes. The challenges facing the industrial and public acceptance of this technology will be assessed. Hence, the key opportunities will be highlighted. Full article

(This article belongs to the Special Issue Wearable Electronics)

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422 KiB

Open AccessReview

Wearable Photoplethysmographic Sensors—Past and Present

by Toshiyo Tamura, Yuka Maeda, Masaki Sekine and Masaki Yoshida

Electronics 2014, 3(2), 282-302; https://doi.org/10.3390/electronics3020282 - 23 Apr 2014

Cited by 664 | Viewed by 63790

Abstract

Photoplethysmography (PPG) technology has been used to develop small, wearable, pulse rate sensors. These devices, consisting of infrared light-emitting diodes (LEDs) and photodetectors, offer a simple, reliable, low-cost means of monitoring the pulse rate noninvasively. Recent advances in optical technology have facilitated the [...] Read more.

Photoplethysmography (PPG) technology has been used to develop small, wearable, pulse rate sensors. These devices, consisting of infrared light-emitting diodes (LEDs) and photodetectors, offer a simple, reliable, low-cost means of monitoring the pulse rate noninvasively. Recent advances in optical technology have facilitated the use of high-intensity green LEDs for PPG, increasing the adoption of this measurement technique. In this review, we briefly present the history of PPG and recent developments in wearable pulse rate sensors with green LEDs. The application of wearable pulse rate monitors is discussed. Full article

(This article belongs to the Special Issue Wearable Electronics)

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