Source: https://nerfgunwar.com/literature-review-beyond-the-limitation-of-portable-power-with-the-smart-shoe-powered-by-iot-technology/
Timestamp: 2019-04-26 08:19:20+00:00

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Beyond the limitation of portable power with the Smart Shoe powered by IOT technology.
In this chapter, we will be focusing on the secondary data used for the study based on books, journal articles, magazines, newspaper, etc. This will be focusing on Piezo electric power generators ,weaknesses of solar power energy generators for the wearable devices and IOT based technology .
(L. Mateu, 2006)Piezoelectric material will generate electric energy when it is pressed. For example, two piezoelectric ?lms which were connected in parallel directly put inside a shoe to generate electric energy from foot step Ref 9.
(L.M. Goncalves, J.G. Rocha, P.F. Rocha, M.P. Silva, S. LancerosMendez, 2010) Rocha, Goncalves and Silva realized a prototype based on an electrostatic generator located in the bottom of the shoe. The energy was gathered by the deformation of dielectric elastomer loaded. Researchers in Portugal have created a prototype using two PVDF piezoelectric sheets placed in zones subject to greater change of pressure .it is observed that energy has increased By coupling piezoelectric elements in this study .
Few prototype of smart shoes were developed by MIT media laboratory in Cambridge using different technologies. One of prototype consisted of glued 8 sheets of PVDF piezoelectric material with dominant polarization on the ?exible plastic sheet . The system recovers energy depend on the flexibility of the sole, generating a mean power of 1.1mW. The second prototype has been developed by the pressure exerted by the heel and using a layer of PZT (piezoelectric ceramic material) mounted on a sheet of spring steel. It could be generating a mean power of 1.8 mW. The last prototype adapts with a standard rotatable electromagnetic generator through a back plate located on the side of the shoe and it is activated by the pressing on the foot , It could be generating a mean power of 0.23 W. (Paradiso, 2001), (Kendall, 1998).According to the MIT studies ,It is observed that more electric power can be generated by second prototype which is capable to generate 1.8mW .The last prototype mentioned above is totally fail because less power generates and physical structure of the device is relatively large and it makes user uncomfortable, Actually it cannot be considered as a wearable smart device .
The smart energy harvesting systems incorporating piezo stack ,piezoelectric PVDF, buzzer with the aim of showing several different possible solutions to recover the energy needed to provide GPS module. As the ?rst solution, a PVDF piezoelectric sheet has been positioned at the place parallel to the heel of the sole (Luchetti, 2013). The shoe should have capability to subject considerable higher stresses .Thus, piezoelectric materials those are characterized by brittle behavior have been considered unsuitable for smart shoes and the choice has fallen on the PVDF material as its ?exibility.
In the second solution there are two energy generating systems four buzzers on the rear of the sole and the ?lm of PVDF piezoelectric material placed on the front of the sole . Though this model is most expensive and complex , this is the most ef?cient during the device operation even in lower weight user situations. The dual power system ensures the continue power generating even in case of failure of one power generating system or ensures the adaptation to any style of walking .
In the third solution, an Energy Harvesting system is based on ?-PVDF piezo electrical material which is capable of generating electric current not only walking, but in compression and when it is bent. In order to exploit this feature the piezoelectric sheet material must be kept folded .In this method maximum bent angle is limited and therefore more piezoelectric sheets should be merged to produce enough voltage to consume .
Frontoni(2013) developed a new device which can be built in a shoe, and the device was assembled ceramic piezo materials and polymer accomplished by injecting molding to implement both outdoor GPS tracker and indoor radio frequency identi?cation (RFID) (E. Frontoni, 2013) .Gatto(2014) presented four different solutions of smart shoes based on PVDF sheet to supply a GPS device .Hwang (2015) designed a piezoelectric floor tile based on PZT piezo material , which are indirect energy transmission using and a tip mass and springs, 55 mW electricity power can be generated through comparison of impedance (S. J. Hwang, and H. ParkH. J. Jung, J. H. Kim, J. H. Ahn, D. Song, T. H. Sung, Y. Song, H. L. Lee, S. P. Moon , 2015). The sole was divided into 8 elements that were connected in parallel, and each element can provide a 2 V open-circuit voltage can be generated when 70kg of weight human wear a shoe ( T. S. Gross and R. P. Bunch, 1988)Almusallam made a screen printed piezoelectric shoe including energy generator using an ?exible PZT-polymer material (A. Almusallam, R. N. Torah, D. Zhu, M. J. Tudor and S. P. Beeby, 2013) Ref 13. Razian(2003) created tri-hub transducer with 10 * 10 *2.7 mm made of PZT to estimation in-shoe force (M. A. Razian and M. G. Pepper, 2003).Moreover Geng (2010) built up a more smaller than normal tri-pivotal piezoelectric transducer made of PZT, which was just 10*10*1 mm (Zh. G. Geng, M. G. Pepper and Y. Yan, n.d.) .Nevill likewise built up a piezoelectric transducer made of copolymer (PVDF-TrFE) to quantify in-shoe press and accomplished an objective of 10% vulnerability ( A. J. Nevill, M. G. Pepper and M. Whiting, 1995).
Since this type piezoelectric transducer can create bigger strain than ?at plate compose, it can enhance the ef?ciency of piezoelectric power generation ( H. S. Kim, J. H. Kim and J. Kim, 2011) .MIT Lab in California teammates investigated an unpretentious 31 mode piezoelectric vitality scavenging based on PZT I sheets in shoes, which is known as a “dimorph”, comprising of two consecutive, single-sided unimorph.. The gadget is to tackle foot strike energy by ?attening bended. Hu propose a ridged PVDF bimorph control collector (H. P. Hu, Ch. Zhao, Sh. Y. Feng, Y. T. Hu, and Ch. Y. Chen, 2008). Also, they demonstrated that the versatility of a gatherer can be enhanced significantly by planning the reaping structure with customizable resounding recurrence., Zhao ( 2014) proposed a sandwich structure that is a multilayer PVDF ?lm sandwiched between two wavy surfaces, which is promptly perfect with a shoe (J. J. Zhao and Zh. You, 2014). The structure can enhance the generating performances since it empowers the PVDF ?lm to produce a substantial longitudinal stretch and diminish the reaper thickness. Additionally, the structure can be coordinated into a shoe whose inward space is restricted. Fourie built up a horseshoe-formed structure, which is situated on the foot rear area of shoes (Fourie, 2010) . PVDF ?lms were embedded in the notches vertically. Amid a foot rear area strike, for the ?exibility of the PVDF ?lm, the ?lm fortified on the plastic ?lm substrate twisted, and the substrate comes back to its previous shape after deformation the piezoelectric charges can be collected.
Kim(2004) built up a piezoelectric transducer in view of PZT which worked in ?ex-tensional (F-T) mode (H. W.Kim, A. Batra, S. Priya, K. Uchino, D. Markley, R. E. Newnham and H. F. Hofmann, 2004).Also Li (2011) built up a piezoelectric transducer which worked in ?ex-compressive (F-C) mode (X. T. Li, M. S. Guo, and Sh. X. Dong,, 2011). The transducer in F-C mode, which exchanges a transversely connected power F into an ampli?ed longitudinal power N to keep piezoelectric clay piece from being broken ,it can withstand a bigger force and enhance output voltage contrasted with F-T mode.
Palosaari produced a piezoelectric power generator using Cymbal design type which was made of PZT (J. Palosaari, M. Leinonen, J. Hannu, J. Juuti, H. Jantunen, 2012) Ref 24. Palosaari demonstrated that the generated power can fulfill the requests of some observing hardware or convenient gadgets., Daniels (2012) create a new piezoelectric power generator gadget that is known as the piezoelectric ?ex transducer (PFT).It can withstand relatively higher powers than cymbal transducer (A. Daniels, M. Zhu and A. Tiwari, 2013).The gadget made of PZT can create a normal most extreme energy of 2.5 mW when retro?tted into a shoe. Yangbuilt up a shell shape power generator, comprising of a PVDF ?lm connected to a bended substrate to overcome the dif?culty that the plan of a piezoelectric transducer required high moving rate to gather energy from human movement (B. Yang and K. S. Yun, 2012) .The structure can create high voltage and power although the user weight is low or the motional is low. Jung composed a capable bended piezoelectric generator by PVDF ?lm which was made of two bended piezoelectric generators associated consecutive (W. S. Jung, M. J. Lee, M. G. Kang, H. G. Moon, S. J. Yoon, S. H. Baek and Ch. Y. Kang, 174–181) .Average Output voltage of 14 V AC of and a average current of 18 mA AC can be gotten by incorporating the structure into a shoe-insole. The piezoelectric transducer in shoe can be intended to create vitality for controlling pedometer. For instance Ishida 2013 built up a shoe insole pedometer that comprises of a piezoelectric power generator and a 2 V natural pedometer circuit (K. Ishida, T. Ch. Huang, K. Honda, Y. Shinozuka, H. Fuketa, T. Yokota, U. Zschieschang, H. Klauk, G. Tortissier, T. Sekitani, H. Toshiyoshi, M. Takamiya, T. Someya, and T. Sakurai, 2013) . PVDF ?lm was utilized as a piezoelectric power generator and it was cut into little pieces and rolled to increase the surface , since generated current of the power generator is proportional to its surface area . Most prominently, one of the PVDF rolls was utilized as a pulse generator to identify step count . In this study, additionally recommended that the recti?ers ought to be appropriated taken after each PVDF those are in parallel to enhance the ef?ciency of the power generator .
Comparing other energy types , cantilever bar is straightforward and perfect. They are compatible with MEMS producing forms, which is about by studied numerous scientists. At the point when the force contact on beams the beam can come back to its initial shape and the inertia will reasoned to the beam make vibration around the underlying area . ( Y. M. Zheng, X. Wu, M. Parmar, and D. W. Lee, 2014).
de?ection is restricted in a useful shoe embed. Mostly shoes which can generate power consists of rectangular-shaped beam type piezoelectric transducers .
This part reviews about piezoelectric material for energy generations transdusers in addition to PZT and PVDF. , Klimiec (2011) developed mini power harvester based on PVDF polypropylene (PP) piezoelectric material to generate energy while walking (Anon., 2012). About 5.3 mW of electric power was produced by single layer PP ?lm and about 3.3 mW of electric power was prodused by poly vinylidene ?uoride ?lm. The collected voltage from polypropylene (PP) is about 12V and about 3.5V for PVDF ?lm. In the present most scientists attention studies about AlN ?lm and ZnO nanoparticles as new piezo electric materials., Elfrink (2009) presented the data sheets of AlN ?lm based piezoelectric energy generating ( R. Elfrink, T. M. Kamel, M. Goedbloed, S. Matova, D. Hohlfeld, Y. V. Andel and R. V. Schaijk,, 2009). The AlN ?lms which has a thickness about 400nm were deposited by reactive sputtering from an Al target. 60 mW output electrical powers can be generated by an unpacked AlN device at an acceleration of 2g with a resonance frequency of 570 Hz. AlN could be considered as a good piezoelectric material because of easiness of processing and high power generation compared to PZT. Prashanthi(2013) fabricated a nanocomposite adding ZnO nanoparticles (NPs) and a photosensitive SU-8 polymer matrix for energy generator ( K. Prashanthi, N. Miriyala, R. D. Gaikwad, W. Moussa, V. RamgopalRao, T. Thundat, 2013).The highly piezoelectric properties of ZnO and the photo-pattern of the SU-8 polymer can be combined by including ZnO nanoparticles into a photosensitive SU-8 polymer matrix. ZnO nanoparticles exhibits the both piezoelectric and semiconducting properties as well as the formation of a Schottky effect at the electrode contact, Due to excellent performances of these nanoparticle piezoelectric transducers, the wide range of study area will be covered by the researches in the future.
Today worldwide are linked into exchanges of data, news and views through Internet. According to Internet World Statistics, as of December 31st in 2011 there was an estimated 2, 267, 233, 000 Internet users worldwide (Anon., n.d.) . While coming to the Things that can be any object or person which can be distinguishable by the real world. Everyday objects include not only electronic devices we encounter and use daily and technologically advanced products such as devices and gadgets, but “things” which we do not normally think of as electronic at all. Such as food, clothing; and furniture; materials, parts and equipment, merchandise and specialized items; landmarks, monuments and works of art and all the miscellany of commerce, culture and sophistication (L.M. Goncalves,J.G. Rocha, P.F. Rocha, M.P. Silva, and S. LancerosMendez, 2010).The Internet of Things (IoT) enabled users to bring physical objects into the sphere of cyber world. This was made possible by different tagging technologies like NFC, RFID and 2D barcode which allowed physical objects to be identified and referred over the internet .
Near Field Communication (NFC) is a set of short range wireless technology at 13.56 MHz, typically requiring a distance of 4 cm. NFC technology makes life easier and more convenient for consumers around the world by making it simpler to make transactions, exchange digital content, and connect electronic devices with a touch. Allows intuitive initialization of wireless networks and NFC is complementary to Bluetooth and 802.11 with their long distance capabilities at a distance circa up to 10 cm. It also works in dirty environment, does not require line of sight, easy and simple connection method. It is first developed by Philips and Sony companies. Data exchange rate now days approximately 424 kbps. Power consumption during data reading in NFC is under 15ma.
ZigBee is one of the protocols developed for enhancing the features of wireless sensor networks. ZigBee technology is created by the ZigBee Alliance which is founded in the year 2001. Characteristics of ZigBee are low cost, low data rate, relatively short transmission range, scalability, reliability, flexible protocol design. It is a low power wireless network protocol based on the 802.15.4 standard (Chen, X.-Y. and Jin, Z.-G, 2012). ZigBee has range of around 100 meters and a bandwidth of 250 kbps and the topologies that it works are star, cluster tree and mesh. It is widely used in home automation, digital agriculture, industrial controls, medical monitoring ; power systems.
Wireless sensors and smart devices can be controlled by the internet anytime and anywhere with the IoT concept. Wireless sensor networks (WSNs) mostly seen in detecting events and identifying surrounding information. Since sensors which are in wearable devices are powered by portable battery , recharging the batteries of smart devices by home electricity is very hard to achieve. For the most of smart online operations, energy generating studies have been much attention through the researchers. The researchers said that energy generating technologies could be applied in, alarm sensors, smart meters, smoke detectors and remote controls. There will be 25 billions of Internet connected devices by 2020 according to calculations of statistics specialists . Wireless sensors which are included in IoT devices are connected to a network will gather information about the environment from the sensor terminals. A key requirement for IoT and M2M concept is the ability to locate place wireless sensors in any kind of locations to obtain the necessary signals .In spite of above there is another big issue is the battery use and life or the installation of power distribution by the wire network or the time period for the replacement of battery . It is worst that fixing this a problem with 10-20 batteries or huge battery with large capacity . there are lots of people those are concerns about not only initial costs for battery but also the large scale of maintenance costs .Those facts reasoned for spread the studies about the portable energy generation with the smart wearable devices. solar cells, piezoelectric elements, and thermoelectric elements are used as power generating elements to convert vibration, light and heat into electric power, then use that electric power efficiently. IoT based technologies and wireless networks would be produced now because semiconductors have achieved a point between the improving power generating element and reduction power consumption of active electronic devices. (Anon., n.d.) .The power generating type must be chosen considering the type of energy to be gathered from the environment, whether light, vibration or heat. Mostly solar, piezoelectric, or thermoelectric are used. power IC for use with the power generating element efficiently should gather the electric power from that element without energy loss. The generated power for each energy harvesting devices changes according to the size and the surrounding environment. It is necessary to consider the following. Selecting a power IC which is suitable for the power generating element. Regarding the selection of wireless communication type between wireless sensor network and computer , the selection can be attached for the power generating element. The communication distance, the type of network, the data transmission speed and the power consumption should be analyzed.
ZigBee ,EnOcean and Bluetooth technologies are low power consumption wireless technologies in the present. There is a point to be considered in energy harvesting, identify power generation and power consumption of the device. This is why of the device will not work if the energy generating is smaller than the consumed power of the device. Although the energy harvesting property of power generating devices are developing day by day, it is less possibility supply continuous power to a device . (Anon., n.d.).To overcome this problem generating energy is collected in a capacitor and execute sensor operation at intervals, resulting in a manner which balances the energy harvesting and power consumption. So the designer requires to have an good understanding of the surrounding environment of the power generating area and amount of the power generated and how long it is required.
RF power harvesting (RFH) is seems as a good method for the proactive power replenishment of next generation wireless networks. Unlike other power generating techniques that rely on the surrounding area, RFH can be on demand or predictable and as such it is better suited for supporting quality-of-service-based applications. However, RFH efficiency is scarce due to low RF-to-DC conversion efficiency and receiver sensitivity. In recent times, RF energy harvesting (RFH) has emerged as a promising technology for alleviating the node energy and network lifetime bottlenecks of wireless sensor networks (WSNs). (Anon., n.d.) .
(Armstrong, n.d.)Piezoelectric micro-electromechanical systems (MEMS) have been found a technology for generating small amplitude of vibrations. This technology gives ability for prevents replacing chemical batteries and complex wiring in circuits, moving us closer toward battery-less autonomous sensors systems and networks. The advantages of piezoelectric MEMS energy generating devices are follows sufficient voltage output, bandwidth, compactness, operating frequency, amplitude of input vibration, cost ,lifetime High power density ratio and wide bandwidth of resonance frequency . Lead-free piezoelectric materials Grown films , grain textured piezoelectric materials and thin films those have high piezoelectric coefficients are recently advancements made toward increasing the electromechanical energy conversion of piezoelectric generating devices . Nonlinear resonators are highly promising to deliver more electric power from the piezo electric beam with wide bandwidth. (Anon., n.d.).
According to Armstrong, at the low part of the power spectrum are the Nano power conversion requirements of energy generating devices likewise those mostly find in IoT devices, which require the use of power conversion ICs which execute in low levels of current and power.. These can be 10 micro- 1Nano amps of current,. State of the art and off the shelf EH technology for example in vibration energy harvesting and indoor or smart wearable photovoltaic cells, yield power levels in the order of milli watts under typical operating conditions. While such power levels may appear restrictive, the operation of harvesting elements over a number of years can mean that the technologies are broadly comparable to long-life primary batteries, both in terms of energy provision and the cost per energy unit provided. Moreover, systems incorporating EH will typically be capable of recharging after depletion something which systems powered by primary batteries cannot do. Nevertheless, most implementations will use an ambient energy source as the primary power source, but will supplement it with a primary battery that can be switched in if the sufficient energy source goes away or is disrupted.
A supercapacitor balancer is also integrated allowing for increased output storage. In 2015, Linear is going to implement the LTC3335 – a nanopower buck-boost DC/DC converter with an integrated coulomb counter obtained at wireless sensor networks and domestic energy harvesting applications. It is a high efficiency, low current (680nA) converter. Its integrated coulomb counter monitors accumulated battery discharge in long life battery powered applications. This counter stores the accumulated battery discharge in an internal register accessible via an I2C interface. The buck boost converter can operate down to1.80 Volts on its input and provides eight pin selectable output voltages with up to 50mA of output current. (sekine, n.d.)The Energy harvesting base wireless sensor network will be widely contribute to improve of constructing, using, maintaining and managing these infrastructures, and reducing environmental pollution obtained to host of Olympic Games in India as Mr. Sekine, obtaining for IoT era, the wireless sensor market expects rapid development with implementing billion of wireless sensors in worldwide. But the battery of each sensor has critical problem with it lifetime and its replacement. According to the iBeacon service which was announced by Apple company also requires battery based Beacon units for its service. Since it hasn’t solved battery-life and its replacement issues, therefore the market hasn’t been exponentially expanded, yet. The wireless sensor market has same issues. Cypress Energy Harvesting solution can solve these issues. Recently, new breakthroughs are made which are 3rd generation of Energy Harvesting of wireless sensor technology. The Bluetooth Low Energy (BLE) technology reduces power consumption compares with traditional protocol. In the present This new protocol is rapidly and broadly adopting in wearable devices. And its advantages of low power consumption and connectivity with Smart devices , the wireless market is also demanding to adopt this protocol. The new trend is going with combination of BLE and Energy Harvesting.
It also made breakthrough in harvester which is perovskite-solar-cell. This new solar cell can generate electricity with high efficiency and can manufacture with low cost. It’s still under research stage but is gathering high interest from Energy Harvesting Industry and solar-cell industry. The battery-less wireless sensor combined of perovskite-solar-cell and BLE is the key technology of upcoming wireless sensor market Cypress is providing 2 types of PMIC (Power Management IC) products as the core of Energy Harvesting. Regarding the Energy Harvesting, to manage time is also important in addition to manage traditional Power Management. Since the generation of electricity in Energy Harvesting system is unstable and small, the high efficient power management technology is crucial. Cypress Energy Harvesting PMICs are developed with focusing on the features of Energy management and high efficient electric power extraction. Our customer can extract electricity efficiently and manage it with leveraging of Energy Harvesting PMIC of MB39C811andMB39C831. India is 2nd largest country of population and has many rapidly developing cities. Therefore India has common problems of fast growing countries such as infrastructures (traffics, electricity, water-supply and gas,) and environment pollution. The advanced wireless sensor network to manage these infrastructures has ability to solve or improve these problems. Particularly, India has Power infrastructure problem, the wireless sensor network with Energy Harvesting is mandatory to precede these approach. The Energy harvesting base wireless sensor network will be widely adopt and contribute to improve of constructing, using, maintaining and managing these infrastructures, and reducing environmental pollution aiming to host of Olympic Games in India .
(Frontoni, 2013.)Internet Protocol (IP) is the primary network protocol used on the Internet, developed in 1970s. IP is the principal communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. The two versions of Internet Protocol (IP) are in use: IPv4 and IPv6. Each version defines an IP address differently. Because of its prevalence, the generic term IP address typically still refers to the addresses defined by IPv4. There are five classes of available IP ranges in IPv4: Class A, Class B, Class C, Class D and Class E, while only A, B, and C are commonly used. The actual protocol provides for 4.3 billion IPv4 addresses while the IPv6 will significantly augment the availability to 85,000 trillion addresses .IPv6 is the 21st century Internet Protocol. This supports around for 2128 addresses.
Energy Harvesting (EH) technologies could be a solution for many power supply related issues especially in IoT & wireless projects. EH technology is not only green and clean but decrease a lot of hassle & also price considerations. We hope to see our future in sight smart cities and smart wearable technologies and industrial technologies to be equipped with EH sensors and power modules with generating power by own.
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