Flat plate type
The piezoelectric foil which can be shaped into an elongated hexagon type to conform to the bending distribution of a standard sole of shoe, as depicted by Paradiso and Shenck
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)
Flat plate type