Self-Sustained Oscillation of a Photothermal-Responsive Pendulum under Steady Illumination

<div>Mechanism of self-excited oscillation of the PSM pendulum, for <span class="nowrap"><svg height="12.5794pt" id="M140" style="vertical-align:-3.29107pt" version="1.1" viewbox="-0.0498162 -9.28833 32.4048 12.5794" width="32.4048pt" 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="M475 507C475 612 440 712 326 712C139 712 23 420 23 215C23 96 58 -12 180 -12C369 -12 475 293 475 507ZM391 522C391 486 387 448 379 394H126C155 538 222 677 310 677C386 677 391 571 391 522ZM373 346C344 193 283 22 189 22C126 22 106 114 106 196C106 243 111 293 118 346H373Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,6.149,3.132)"><path d="M245 635C92 635 37 457 37 312C37 149 91 -12 244 -12C395 -12 449 166 449 312C449 469 395 635 245 635ZM243 598C332 598 358 454 358 312C358 173 334 26 245 26C158 26 128 174 128 313S152 598 243 598Z"></path></g><g transform="matrix(.013,0,0,-0.013,14.727,0)"><path d="M535 323V373H52V323H535ZM535 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Mathematical Problems in Engineering

fig4

Figure 4

Figure 4: Self-Sustained Oscillation of a Photothermal-Responsive Pendulum under Steady Illumination 