Photo-Activated Snap-Through of Nematic Shallow Spherical Shells

Photo-responsive nematic polymers can transduce light into mechanical work, but the rate is limited by the quasi-static deformation. To enhance the work output, a strategy of exploiting photo-triggered snap-through of glassy nematic shallow spherical shells with hemeotropic director alignment is examined here. The criterion for the nonlinear instability is derived analytically by using the modified iteration method. It is shown that, for thin shells of small height and large basal radius, snap-through can be caused by an incident light with moderate irradiation intensity. The phenomenon may inspire some new designs of contactless and ultra-fast actuation devices with high-rate output of mechanical work.