Microstereolithography of Three-Dimensional Polymeric Springs for Vibration Energy Harvesting

<table class="table-group" id="tab4"><tr><td><table class="table"><tr><td class="thead-hr" colspan="7"><hr/></td></tr><tr class="thead"><td align="left">Generator</td><td align="center">Freq (Hz)</td><td align="center">Material</td><td align="center">Young’s modulus (GPa)</td><td align="center">Largest feature size (mm)</td><td align="center">Density g/cm<sup>3</sup></td><td align="center">Spring dimensions (mm)</td></tr><tr><td class="thead-hr" colspan="7"><hr/></td></tr><tr><td align="left">This work EM</td><td align="center">61</td><td align="center">HDDA</td><td align="center">0.53</td><td align="center">3.4</td><td align="center">1.011</td><td align="center"><svg height="11.225" id="M89" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 90.6875 11.225" width="90.6875" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,10.963)"><use xlink:href="#x30"></use></g><g transform="matrix(.017,-0,0,-.017,8.222,10.963)"><use xlink:href="#x2E"></use></g><g transform="matrix(.017,-0,0,-.017,12.098,10.963)"><use xlink:href="#x31"></use></g><g transform="matrix(.017,-0,0,-.017,20.257,10.963)"><use xlink:href="#x36"></use></g><g transform="matrix(.017,-0,0,-.017,28.416,10.963)"><use xlink:href="#x30"></use></g><g transform="matrix(.017,-0,0,-.017,40.35,10.963)"><use xlink:href="#xD7"></use></g><g transform="matrix(.017,-0,0,-.017,54.102,10.963)"><use xlink:href="#x30"></use></g><g transform="matrix(.017,-0,0,-.017,62.261,10.963)"><use xlink:href="#x2E"></use></g><g transform="matrix(.017,-0,0,-.017,66.137,10.963)"><use xlink:href="#x34"></use></g><g transform="matrix(.017,-0,0,-.017,74.296,10.963)"><use xlink:href="#x30"></use></g><g transform="matrix(.017,-0,0,-.017,82.455,10.963)"><use xlink:href="#x30"></use></g>
</svg> springs, 3.4 height</td></tr><tr><td align="left">Beeby, 2007 [<a href="/journals/smr/2012/741835/#B24">24</a>] EM</td><td align="center">52</td><td align="center">Double-polished single crystal silicon wafers</td><td align="center">185</td><td align="center">9</td><td align="center">2.329</td><td align="center"><svg height="11.175" id="M90" style="vertical-align:-0.20474pt" version="1.1" viewbox="0 0 88.025002 11.175" width="88.025002" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,10.862)"><path d="M244 635q90 0 143 -72t53 -177q0 -133 -65 -229.5t-171 -139.5q-79 -32 -140 -32l-5 30q109 18 185 91t101 186l-68 -36q-29 -16 -60 -16q-79 0 -129 51.5t-50 130.5q0 80 57 146.5t149 66.5zM228 602q-52 0 -78 -45.5t-26 -98.5q0 -69 36.5 -115.5t97.5 -46.5
q53 0 90 28q4 31 4 66q0 51 -9.5 95.5t-39 80.5t-75.5 36z" id="x39"></path></g><g transform="matrix(.017,-0,0,-.017,11.996,10.862)"><use xlink:href="#xD7"></use></g><g transform="matrix(.017,-0,0,-.017,25.748,10.862)"><use xlink:href="#x33"></use></g><g transform="matrix(.017,-0,0,-.017,37.681,10.862)"><use xlink:href="#xD7"></use></g><g transform="matrix(.017,-0,0,-.017,51.433,10.862)"><use xlink:href="#x30"></use></g><g transform="matrix(.017,-0,0,-.017,59.592,10.862)"><use xlink:href="#x2E"></use></g><g transform="matrix(.017,-0,0,-.017,63.468,10.862)"><use xlink:href="#x30"></use></g><g transform="matrix(.017,-0,0,-.017,71.627,10.862)"><use xlink:href="#x35"></use></g><g transform="matrix(.017,-0,0,-.017,79.787,10.862)"><use xlink:href="#x30"></use></g>
</svg> beam</td></tr><tr><td align="left">Ching, 2001 [<a href="/journals/smr/2012/741835/#B25">25</a>] EM</td><td align="center">110</td><td align="center">Copper</td><td align="center">110–128</td><td align="center">4</td><td align="center">8.94</td><td align="center">4 radius planar spring</td></tr><tr><td align="left">White, 2001 [<a href="/journals/smr/2012/741835/#B26">26</a>] PZ</td><td align="center">80</td><td align="center">AISI 316 steel and PZT</td><td align="center">193 and 49–63</td><td align="center">23</td><td align="center">8 and 7.5–7.6</td><td align="center">Trapezoid beam, 23 base, 11 top, and 10 height</td></tr><tr><td align="left">Park, 2010/11 [<a href="/journals/smr/2012/741835/#B27">27</a>, <a href="/journals/smr/2012/741835/#B28">28</a>] EM</td><td align="center">54</td><td align="center">100 silicon wafer</td><td align="center">185</td><td align="center">8</td><td align="center">2.329</td><td align="center"><svg height="11.125" id="M91" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 79.862503 11.125" width="79.862503" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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t98.5 -62.5q61 48 61 124q0 59 -29.5 90t-69.5 31zM248 20q46 0 76.5 33.5t30.5 89.5q0 50 -39 85.5t-110 71.5q-81 -54 -81 -137q0 -67 35.5 -105t87.5 -38z" id="x38"></path></g><g transform="matrix(.017,-0,0,-.017,11.996,10.862)"><use xlink:href="#xD7"></use></g><g transform="matrix(.017,-0,0,-.017,25.748,10.862)"><use xlink:href="#x38"></use></g><g transform="matrix(.017,-0,0,-.017,37.681,10.862)"><use xlink:href="#xD7"></use></g><g transform="matrix(.017,-0,0,-.017,51.433,10.862)"><use xlink:href="#x30"></use></g><g transform="matrix(.017,-0,0,-.017,59.592,10.862)"><use xlink:href="#x2E"></use></g><g transform="matrix(.017,-0,0,-.017,63.468,10.862)"><use xlink:href="#x30"></use></g><g transform="matrix(.017,-0,0,-.017,71.627,10.862)"><use xlink:href="#x34"></use></g>
</svg> planar spring</td></tr><tr><td align="left">Serre, 2007 [<a href="/journals/smr/2012/741835/#B29">29</a>] EM</td><td align="center">920</td><td align="center">Kapton polymer membrane</td><td align="center">2.5</td><td align="center">11</td><td align="center">2.7552 slugs/ft3</td><td align="center"><span style="width: 104.3375px;"><svg height="11.125" id="M92" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 104.3375 11.125" width="104.3375" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,10.862)"><use xlink:href="#x31"></use></g><g transform="matrix(.017,-0,0,-.017,8.222,10.862)"><use xlink:href="#x31"></use></g><g transform="matrix(.017,-0,0,-.017,20.155,10.862)"><use xlink:href="#xD7"></use></g><g transform="matrix(.017,-0,0,-.017,33.907,10.862)"><use xlink:href="#x31"></use></g><g transform="matrix(.017,-0,0,-.017,42.066,10.862)"><use xlink:href="#x31"></use></g><g transform="matrix(.017,-0,0,-.017,54,10.862)"><use xlink:href="#xD7"></use></g><g transform="matrix(.017,-0,0,-.017,67.752,10.862)"><use xlink:href="#x30"></use></g><g transform="matrix(.017,-0,0,-.017,75.911,10.862)"><use xlink:href="#x2E"></use></g><g transform="matrix(.017,-0,0,-.017,79.787,10.862)"><use xlink:href="#x31"></use></g><g transform="matrix(.017,-0,0,-.017,87.946,10.862)"><use xlink:href="#x32"></use></g><g transform="matrix(.017,-0,0,-.017,96.105,10.862)"><use xlink:href="#x38"></use></g>
</svg></span></td></tr><tr><td align="left">Yang, 2009 [<a href="/journals/smr/2012/741835/#B30">30</a>] EM</td><td align="center">350–600</td><td align="center">Acrylic</td><td align="center">3.2</td><td align="center">54</td><td align="center">1.4</td><td align="center"><svg height="11.225" id="M93" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 67.824997 11.225" width="67.824997" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,10.963)"><use xlink:href="#x35"></use></g><g transform="matrix(.017,-0,0,-.017,8.222,10.963)"><use xlink:href="#x34"></use></g><g transform="matrix(.017,-0,0,-.017,20.155,10.963)"><use xlink:href="#xD7"></use></g><g transform="matrix(.017,-0,0,-.017,33.907,10.963)"><use xlink:href="#x36"></use></g><g transform="matrix(.017,-0,0,-.017,45.84,10.963)"><use xlink:href="#xD7"></use></g><g transform="matrix(.017,-0,0,-.017,59.592,10.963)"><use xlink:href="#x31"></use></g>
</svg> beam</td></tr><tr><td align="left">Swallow, 2008 [<a href="/journals/smr/2012/741835/#B9">9</a>] PZ</td><td align="center">25–100</td><td align="center">Copper and PFC</td><td align="center">110–128 and 50 [31]</td><td align="center">171</td><td align="center">8.94 and 7.65</td><td align="center"><span style="width: 58.450001px;"><svg height="11.125" id="M94" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 58.450001 11.125" width="58.450001" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,10.862)"><use xlink:href="#x31"></use></g><g transform="matrix(.017,-0,0,-.017,8.222,10.862)"><use xlink:href="#x37"></use></g><g transform="matrix(.017,-0,0,-.017,16.381,10.862)"><use xlink:href="#x31"></use></g><g transform="matrix(.017,-0,0,-.017,28.314,10.862)"><use xlink:href="#xD7"></use></g><g transform="matrix(.017,-0,0,-.017,42.066,10.862)"><use xlink:href="#x32"></use></g><g transform="matrix(.017,-0,0,-.017,50.226,10.862)"><use xlink:href="#x32"></use></g>
</svg></span></td></tr><tr class="table-tr"><td colspan="7"><hr class="tbody-hr"/></td></tr></table></td></tr></table>

Smart Materials Research

tab4

Table 4

Table 4: Microstereolithography of Three-Dimensional Polymeric Springs for Vibration Energy Harvesting 