Model-Based Experimental Development of Passive Compliant Robot Legs from Fiberglass Composites

<div>The resultant stiffness (a) and equivalent elastic moduli (b) of the fiberglass composite strips made by the E-glass <svg height="13.0648pt" id="M74" style="vertical-align:-2.268101pt" version="1.1" viewbox="-0.0498162 -10.7967 70.4587 13.0648" width="70.4587pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z" id="g113-41"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="346" vert-adv-y="346"></glyph.data></g><g transform="matrix(.013,0,0,-0.013,4.498,0)"><path d="M535 230V280H52V230H535Z" id="g117-33"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="587" vert-adv-y="587"></glyph.data></g><g transform="matrix(.013,0,0,-0.013,12.129,0)"><path d="M456 178V225H360V632H320C217 496 115 347 20 206V178H280V106C280 40 276 34 189 27V0H445V27C364 34 360 39 360 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366 395 238 395C212 395 165 379 127 364L153 550Z" id="g121-51"></path><glyph.data ascent="989" descent="-360" horiz-adv-x="480" vert-adv-y="480"></glyph.data></g><g transform="matrix(.0091,0,0,-0.0091,61.738,-5.741)"><path d="M339 262C339 340 273 403 193 403S48 340 48 262S113 121 193 121S339 184 339 262ZM283 262C283 210 242 168 193 168S104 210 104 262S144 356 193 356S283 314 283 262Z" id="g54-73"></path><glyph.data ascent="3443" descent="-2856" horiz-adv-x="385" vert-adv-y="385"></glyph.data></g><g transform="matrix(.013,0,0,-0.013,65.753,0)"><path d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z" id="g113-42"></path><glyph.data ascent="3473" descent="-2876" horiz-adv-x="346" vert-adv-y="346"></glyph.data></g></svg> and the E-glass <svg height="13.0648pt" id="M75" style="vertical-align:-2.268101pt" version="1.1" viewbox="-0.0498162 -10.7967 19.4075 13.0648" width="19.4075pt" xmlns="http://www.w3.org/2000/svg" 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Applied Bionics and Biomechanics

fig9

Figure 9

Figure 9: Model-Based Experimental Development of Passive Compliant Robot Legs from Fiberglass Composites 