An impedance tunable and highly efficient triboelectric nanogenerator for large-scale, ultra-sensitive pressure sensing applications

Rasel, M. Salauddin,Maharjan, Pukar,Salauddin, Md.,Rahman, M. Toyabur,Cho, Hyun Ok,Kim, Jae Woo,Park, Jae Yeong Elsevier 2018 Nano energy Vol.49 No.-

<P><B>Abstract</B></P> <P>Precise triboelectric nanogenerators (TENGs) with large-scale pressure sensing ability can be realized by effectively harvesting physical pressure. Extensive research on efficient pressure sensors is ongoing, yet the pressure detection limit and sensitivity of most of the reported pressure sensors are not satisfactory for practical and wearable device applications. Herein, we demonstrate a highly efficient approach toward detecting a wide range of pressures, from 5 kPa to 450 kPa, with a record high sensitivity of 0.51 V/kPa. We aim at maximizing the energy conversion efficiency of 48.17% by optimally tuning the internal impedance of the triboelectric nanogenerator at 2.5 MΩ, because low internal impedance results in high output power. This paper reports the structural design, fabrication, and experimental validation of a self-powered and highly durable TENG pressure sensor for large-scale pressure detection based on double-side tribological layers of micro-patterned polydimethylsiloxane (PDMS) and PDMS-multiwall carbon nanotube (CNT) nanocomposites. An in-sole application of the proposed TENG is demonstrated for varying foot pressures corresponding to different walking patterns, which is likely to be applicable in sports sciences, high-risk diabetic foot ulceration, and rehabilitation. Our present contribution not only facilitates large-scale pressure sensing but also paves the way toward the realization of next-generation self-powered and maintenance-free sensing devices.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A self-powered triboelectric nanogenerator with record high pressure detection range (From 5 kPa to 450 kPa). </LI> <LI> A maximum of 0.51 V/kPa sensitivity. </LI> <LI> Up to 48.17% energy conversion efficiency. </LI> <LI> Low internal impedance of 2.5 MΩ. </LI> <LI> In-sole application. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Design and experiment of hybridized electromagnetic-triboelectric energy harvester using Halbach magnet array from handshaking vibration

Salauddin, M.,Rasel, M.S.,Kim, J.W.,Park, Jae Y. Elsevier 2017 Energy conversion and management Vol.153 No.-

<P><B>Abstract</B></P> <P>We have proposed a new design of hybridized electromagnetic-triboelectric energy harvester using Halbach magnet array from handshaking vibration and validated it theoretically and experimentally. The Halbach array helps to enhance the magnetic flux density and reduce the overall volume as well as generate high power at low frequency. In particular, the proposed dual Halbach array allows the concentrated magnetic flux lines to interact with the same coil in a way where maximum flux linkage occurs. To obtain much higher power generation in low amplitude and low frequency vibrations, the proposed harvester was comprised of a Halbach magnet array, sandpaper passed microstructure PDMS, TENG, and magnetic springs. A prototype of the hybridized energy harvester has been fabricated and tested both using a vibration exciter test and by manual handshaking. Under vibration exciter test, the fabricated prototype of hybridized harvester delivered a high output current and power of 2.9mA and 11.75mW, respectively, corresponding to a volume power density of 381W/m<SUP>3</SUP> under a loading resistance of 1.39kΩ at 5Hz resonant frequency and 0.5g acceleration. It is also capable of delivering output current and power of 2.85mA and 8.1mW, respectively, by handshaking vibration. The fabricated hybridized harvester exhibited much higher power density than the recently reported similar works. Our proposed work takes a significant step toward hybrid energy harvesting from human-body-induced motions such as handshaking, walking, running and its potential applications in self powered portable electronics.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A new hybrid energy harvester design has been proposed and verified. </LI> <LI> Low frequency driven electromagnetic-triboelectric hybrid mechanism. </LI> <LI> Halbach array converges the magnetic flux density and helps higher power density. </LI> <LI> Sandpaper assisted inexpensive micro-patterned PDMS film has been utilized. </LI> </UL> </P>

A magnetic-spring-based, low-frequency-vibration energy harvester comprising a dual Halbach array

Salauddin, M,Halim, M A,Park, J Y IOP 2016 Smart materials & structures Vol.25 No.9

<P>Energy harvesting that uses low-frequency vibrations is attractive due to the availability of such vibrations throughout the ambient environment. Significant power generation at low-frequency vibrations, however, is challenging because the power flow decreases as the frequency decreases; moreover, designing a spring-mass system that is suitable for low-frequency-vibration energy harvesting is difficult. In this work, our proposed device overcomes both of these challenges by using a dual Halbach array and magnetic springs. Each Halbach array concentrates the magnetic-flux lines on one side of the array while suppressing the flux lines on the other side; therefore, a dual Halbach array allows for an interaction between the concentrated magnetic-flux lines and the same coil so that the maximum flux linkage occurs. During the experiment, vibration was applied in a horizontal direction to reduce the gravity effect on the Halbach-array structure. To achieve an increased power generation at low-amplitude and low-frequency vibrations, the magnetic structure of the dual Halbach array and the magnetic springs were optimized in terms of the operating frequency and the power density; subsequently, a prototype was fabricated and tested. The prototype device offers a normalized power density of 133.45 <I>μ</I>W cm<SUP>−3</SUP> g<SUP>−2</SUP> that is much higher than those of recently reported electromagnetic energy harvesters; furthermore, it is capable of delivering a maximum average power of 1093 <I>μ</I>W to a 44 Ω optimum load, at an 11 Hz resonant frequency and under a 0.5 g acceleration.</P>

Miniaturized springless hybrid nanogenerator for powering portable and wearable electronic devices from human-body-induced vibration

Salauddin, Md,Toyabur, R.M.,Maharjan, P.,Rasel, M.S.,Kim, J.W.,Cho, Hyunok,Park, Jae Yeong Elsevier 2018 Nano energy Vol.51 No.-

<P><B>Abstract</B></P> <P>In this paper, a springless hybridized NG (nanogenerator) was newly designed to have a non-resonant behavior, in which the output power continuously increases with the input frequency and amplitude. To achieve a considerably higher output power generation at low-frequency vibrations and low amplitude, the proposed springless hybrid electromagnetic and triboelectric nanogenerator (SHEMG-TENG) utilizes a dual-Halbach array, which is fabricated with contact-separation and sliding-mode TENGs. The proposed SHEMG-TENG is fabricated and verified from a vibration exciter and human-body-induced vibration. Under the vibration exciter test (horizontal position), the fabricated SHEMG-TENG generated an output current and power of 2.04 mA and 5.41 mW, respectively, which corresponds to a volume power density of 395.4 W/m<SUP>3</SUP> under a matching load resistance of 1.1 KΩ at an applied frequency and acceleration of 6 Hz and 1 g, respectively. For a number of basic human activities such as handshaking, walking, and slow running, the SHEMG-TENG was able to deliver output powers are 2.9 mW, 1.2 mW, and 1.7 mW (horizontal position), respectively, and 1.6 mW, 0.74 mW, and 2.3 mW (vertical position), respectively. This work presents an important step toward realizing SHEMG-TENG from human-body-induced vibration powered to enable wearable and portable smart electronic applications, and is expected to be widely accepted by the general public in their daily lifestyle.</P> <P><B>Highlights</B></P> <P> <UL> <LI> New design and modeling of springless hybrid nanogenerator. </LI> <LI> EMG, contact-separation and sliding mode of TENG. </LI> <LI> Dual Halbach magnet array, nano structured of PTFE, Al grass, and Al porous. </LI> <LI> Higher output-power generation in non-resonant and low-frequency operation. </LI> <LI> Powered wearable and portable electronic devices. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Hand clapping inspired integrated multilayer hybrid nanogenerator as a wearable and universal power source for portable electronics

Rasel, M. Salauddin,Maharjan, Pukar,Park, Jae Yeong Elsevier 2019 Nano energy Vol.63 No.-

<P><B>Abstract</B></P> <P>We report a human skin-based wearable and hybrid triboelectric-piezoelectric nanogenerator (HTEPENG) for harvesting biomechanical energy from hand clapping to eliminate the need for batteries to drive portable electronic devices. Through smart integration of polyimide encapsulated polarized polyvinylidene fluoride (PVDF) film between two nanopillar polydimethylsiloxane (n-PDMS) films, the hybrid nanogenerator can produce two triboelectric outputs and one piezoelectric output simultaneously upon a single clap. The output performances of the HTEPENG have been optimized through systematic analysis and experimental validation of the surface morphology and coupling effect of interfacing materials. The as-fabricated HTEPENG device delivers a peak power density of 3.7 W/m<SUP>2</SUP> at a matched resistance of 23.08 MΩ. After the use of a custom-designed power conversion and management system (PCMS), the nanogenerator was able to drive a commercial pedometer and successfully recharged a trimmer, pocket Wi-Fi router, and smartphone individually, which might speed up commercialization of the wearable nanogenerators. Furthermore, the HTEPENG possesses a unique characteristic of modulated multi-level outputs, which has the potential to bring extensive application prospects in the field of logic devices, power supply, prosthetics, antistatic protection, and self-powered sensor networks. Even though clapping is a natural human activity to applaud somebody which is very common in many environments like a concert, theatre, and stadium, it is also well known to improve the overall human health by improving the blood circulation to various organs. Thereby, other than serving as a universal power source, the proposed hybrid nanogenerator can promote additional health benefit for the human.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Hand clapping inspired biomechanical energy harvesting from skin-contact is reported. </LI> <LI> Charge compensation problem of conventional multilayer nanogenerators is solved. </LI> <LI> The concept of multi-level outputs of the nanogenerator is newly established. </LI> <LI> The output performance of the hybrid nanogenerator is optimized systematically. </LI> <LI> A power management circuit is introduced for powering portable electronics. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Electromagnetic energy harvester based on a finger trigger rotational gear module and an array of disc Halbach magnets

Kim, Jae Woo,Salauddin, Md,Cho, Hyunok,Rasel, M. Salauddin,Park, Jae Yeong Elsevier 2019 APPLIED ENERGY Vol.250 No.-

<P><B>Abstract</B></P> <P>We propose a non-resonant finger-triggered electromagnetic energy harvester (EMEH) using multiple gear modules and an array of disc Halbach magnets, which can generate significant voltage and power under low input-frequency vibrations. The proposed EMEH converts the applied low frequencies into higher frequencies using a multiplying gear module and forwards the linear excitation to a rotational module by gear parts. The multiplying gear module was used for increasing the speed of magnet motion. In the energy generation part, an array of disc Halbach magnets were used for concentrating the magnetic flux toward the coils. The proposed energy harvester generated an open-circuit voltage of 1.39 V at an average power of 7.68 mW, with an optimal load of 36 Ω at an input frequency of 3 Hz. The prototype harvester offers a power density of 0.833 mWcm<SUP>−3</SUP>, which is much higher than those of recently reported EMEHs. We demonstrate wearable and portable electronics such as a stopwatch and pedometer-based on finger triggering. This study presents an important step toward low-frequency-vibration-powered devices for portable smart electronic applications and is expected to be widely applicable.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Finger-triggered EMEH using gear modules and Halbach magnets array. </LI> <LI> Non-resonant output behavior of the EMEH. </LI> <LI> Frequency up conversion through multiple gear module. </LI> <LI> Low-frequency vibration based EMEH for portable smart electronics application. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Nanogenerator for scavenging low frequency vibrations

Park, Jae Yeong,Salauddin, Md,Rasel, M Salauddin IOP 2019 Journal of micromechanics and microengineering Vol.29 No.5

<P>Energy harvesting technologies have being developed swiftly in the last couple of years owing to the recent developments of low power consuming features of portable and wearable electronic devices. For operating these devices and systems, eco-friendly and low frequency vibration based nanogenerators have been researched and developed. The major reason behind this rapid growth of such nanogenerators is the abundance of low frequence vibrations, which exist almost everywhere and have the potential to be easily harvested by many different transduction mechanisms. This paper reviews the key ideas and performances of these reported nanogenerators for scavenging energy from low frequency vibrations. In addition, various types of vibration sources, approaches, device architectures, materials, fabrications and practical applications of these energy scavenging devices are also reviewed.</P>

A fully enclosed, 3D printed, hybridized nanogenerator with flexible flux concentrator for harvesting diverse human biomechanical energy

Maharjan, Pukar,Cho, Hyunok,Rasel, M. Salauddin,Salauddin, Md.,Park, Jae Yeong Elsevier 2018 Nano energy Vol.53 No.-

<P><B>Abstract</B></P> <P>Human body motion is highly regarded as a promising source of energy for powering body-worn electronic devices and health monitoring sensors. Transforming the human biomechanical energy into an electrical energy provides a sustainable energy to drive those devices and sensors, reducing their battery dependency. This work presents a fully-enclosed wrist-wearable hybridized electromagnetic-triboelectric nanogenerator (FEHN) for effectively scavenging energy from the low-frequency natural human wrist-motion (≤ 5 Hz). The FEHN incorporates the rolling electrostatic induction and electromagnetic induction using a freely moving magnetic ball inside a hollow circular tube. The materials used in 3D printing technology are used as energy harvesting material for easy, quick and worthwhile fabrication of the FEHN. A thin flexible flux concentrating material is introduced to increase the emf and enhances the electromagnetic output performance. The FEHN can harvest energy under the diverse circumstances and irregular wrist-motions, such as swinging, waving, shaking, etc. Following the experiments, the FEHN achieves an average power density of 0.118 mW cm<SUP>−3</SUP> and can drive a commercial wrist-watch continuously for more than 23 min from just 5 s of wrist motion. This successful demonstration renders an effective approach for scavenging wasted biomechanical energy and provides a promising solution towards the development of sustainable power supply for wearable electronic devices and self-powered healthcare monitoring sensors.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A fully enclosed, 3D printed and hybridized nanogenerator, isolated from external environment is newly developed </LI> <LI> Sustainable nanogenerator for powering body-worn wearable electronic devices and healthcare monitoring sensors. </LI> <LI> Highly capable of harvesting energy from diverse wrist motions such as swinging, waving, shaking, twisting, etc. </LI> <LI> A flexible FeSiCr/PDMS composite based flux concentrator around the copper coil is applied to increase the induced emf. </LI> <LI> 5 s of wrist motion is enough to power a commercial electronic wrist-watch for more than 23 min continuously. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Spatial optimisation of mango leather production and colour estimation through conventional and novel digital image analysis technique

Sarkar Tanmay,Salauddin Molla,Choudhury Tanupriya,Um Jung-Sup,Pati Siddhartha,Hazra Sudipta Kumar,Chakraborty Runu 대한공간정보학회 2021 Spatial Information Research Vol.29 No.4

Being a seasonal fruit mango cannot be cherished over the year; dehydration may be a solution to preserve the deliquesce of mango as mango leather. The processing parameters like puree load (0.4–0.6 g/cm2 ), total soluble solid (20–30 B), oven temperature (60–80 C), and microwave power level (100–300 W) were optimised for a superior textural attribute (hardness) primitive drying method like sun drying, industrially practiced modern methods like hot air oven drying and microwave drying and cutting-edge drying technique like freeze-drying. Response surface methodology and artificial neural network technique were adapted to model these drying procedures by considering the central composite design. The mathematical operations guiding to describe the model were studied. Being an imperative parameter colour quantification is essential for food industries. Current research employs microwave drying to produce mango leather with colour quantification approach. The L, ‘a’ and ‘b’ values of the product have been measured by Hunter Lab colorimeter and by digital image analysis, to determine the chromatic view harmonious to human vision. The relative analysis of colour measurement through these two techniques has been studied.

Prevalence of Feline Leukemia Virus Infection in Cats in Bangladesh

Siddiqur Rahman,Salauddin Bhuiyan,Taohidul Islam,Azimun Nahar,Roma Rani Sarker,Emtiaj Alam,Amitavo Chakrabarty,Abu Sayed Sarker,Laila Akhter,채준석 한국임상수의학회 2014 한국임상수의학회지 Vol.31 No.1

Feline leukemia virus (FeLV) is a retrovirus that represents one of the most common and important infectiousdiseases of cats worldwide and it is responsible for more deaths among cats than any other infectious diseases. Prevalence data are necessary to define prophylactic, management and therapeutic measures for stray, feral and ownedcats which are lacking in Bangladesh. The study was carried out to determine the prevalence of FeLV infection inMymensingh district of Bangladesh using RapiGEN® FeLV Ag Test Kit (RapiGEN® Inc., Republic of Korea), a rapidone-step immunochromatographic assay. Blood samples from total 130 cats (23 owned cats and 107 unowned cats)were collected and tested following the manufacturer’s instruction. An overall prevalence of FeLV infection was 1.54%(2/130). Prevalence was found 1.79% (2/112) on Day 0-up to one year aged cats (young) but no positive case wasfound in above 1 year (Adult) aged group. In male and female cats, the prevalence was 1.72% (1/58) and 1.39%(1/72), respectively. In un-owned cats the prevalence was 1.87%. Positive cases to FeLV were found only in clinicallysick cats. No significant relationship was found according to age, sex, ownership status and health status. To the bestof our knowledge this is the first report of the prevalence of FeLV infection in Bangladesh using RapiGEN® FeLVtest kits which is very much effective because it is easy to apply, less expensive and quick screening of such typeof infection.