Energy harvesters, dielectric elastomer

From Boots to Buoys Promises and Challenges of Dielectric Elastomer Energy Harvesting... 

RD Kornbluh, R Pelrine, H Prahlad, A Wong-Foy, B McCoy, S Kim, J Eckerie, T Low, From Boots to Buoys Promises and Challenges of Dielectric Elastomer Energy Harvesting, SPIE Proc 7976 48-66, Bellingham, WA, 2011 [doi 10.1117/12.882367], reprinted with permission. 

We conclude with a discussion that summarizes the challenges that remain and how they can be addressed. It is a thesis of this paper that dielectric elastomer energy harvesting does indeed offer great potential if such challenges can be overcome. 

SRI developed and demonstrated the use of dielectric elastomers for harvesting the energy of ocean waves. This work included two sea trials in which SRI deployed a complete energy harvesting system at sea. Figure 3.7 shows the system for the first sea trial conducted in Tampa Bay near St. Petersburg, Florida. 

Keywords Dielectric elastomer Electroactive polymer Transducer Energy harvesting Lifetime Wave powerwave power... 

Next, we will introduce specific examples of energy harvesting systems that have been built or contemplated by the authors or collaborators. In addition to highlighting the potential of dielectric elastomer power generation, this section will also provide specihc examples of the systems-related issues and serve as a springboard for a discussion of these system issues such as lifetime. 

We have already touched on some of the unique properties of dielectric elastomers and the implications for energy harvesting. These unique properties and their implications are as follows ... 

Fig. 3.5 Notional dielectric elastomer devices that can harvest human kinetic energy. Kinetic energy is available from vertical motion and from the negative work done at the ankles, knees, and hips. Energy harvesting devices can be strategically located in equipage to selectively harvest this energy in order to provide power to electronic systems. This arrangement will not hamper mobility and should actually reduce fatigue. [Source adapted from Infoscitex Corp. and SRI International]...

B = Energy harvesting electronics C = Dielectric elastomer rolls... 

In this analysis, the dielectric elastomer transducer and energy harvesting circuits were modeled with highly simplified, experimentally validated lumped parameter models that did not include the interactions resulting from Eq. 3.1. Such models also did not include aU of the nonlinear effects detailed in Sect. 3.2 above. The circuits were also modeled separately using more specialized circuit modeling... 

Fig. 3.10 Highly modular distributed ocean wave energy harvesting system based on dielectric elastomer transducers...

In this chapter, we extend and apply the results on EAP materials and models to a few device and robotic applications. A robotic fish propelled by an IPMC caudal fin is first considered in Section 9.1. The use of IPMC for low-frequency energy harvesters is studied in Section 9.2. The design of an IPMC-enabled valveless pump is discussed in Section 9.3. We then present a novel micropump actuated by conjugated polymer petals, supported by both analytical and experimental results. Finally, in Section 9.5 we investigate the design, prototyping, and control of a robotic finger powered by dielectric elastomer actuators. 

Electro-electret (dielectric-elastomer actuator, sensor or energy harvester) External voltage induces charges on compliant electrodes Compression/ rarefaction of elastomer (charges stay on soft electrodes) Incompressibility leads to change in length/width or to bending... 

Ju W-E, Moon Y-J, Park C-H, Choi ST (2014) A flexible tactile-feedback touch screen using transparent ferroelectric polymer film vibrators. Smart Mater Stmct 23 074004-1-074004-10 Kawai H (1969) The piezoelectricity of poly (vinylidene fluoride). Jpn J Appl Phys 8 975-976 Kombluh RD, PeWne R, Prahlad H, Wong-Foy A, McCoy B, Kim S, Eckerle J, Low T (2012) Dielectric elastomers stretching the capabilities of energy harvesting. MRS Bnll 37 246-253 Lacour SP, Jones J, Wagner S, Li T, Suo Z (2005) Stretchable interconnects for elastic electronic surface. Proc IEEE 93 1459-1467... 

The unique advantages of dielectric elastomers have stimulated a great number of apphcations which can be categorized into actuators, energy harvesters, and sensors. This chapter presents multiple electromechanical transduction systems including biologically inspired robotics, tactile feedback and displays, tunable optics, fluid control and microfluidics, capacitive sensors, and energy harvesters. 

Brochu P (2012) Dielectric elastomers for actuation and energy harvesting. University of California, Los Angeles... 

Czech B, van Kessel R, Bauer P et al (2010) Energy harvesting using dielectric elastomers. In Proceedings of 14th international power electron motion control conference EPE-PEMC, Ohrid, S4,pp 18-23... 

Gisby TA, Xie SQ, CaUus EP, Anderson lA (2010) Leakage current as a predictor of failure in dielectric elastomer actuators. Proc SPIE 7642 764213. doi 10.1117/12.847835 Graf C, Maas J (2011) Energy harvesting cycles based on electro active polymers. Proc SPIE 7642 764217. doi 10.1117/12.853597... 

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