Fig. 2: Instability-induced undulation and bifurcation.
From: Bio-inspired multimodal soft actuator with environmental self-adaptation
A Schematics and snapshots of the asymmetric trilayer during the undulation cycle from optical images, IR images, and simulation results. B Actuation stress of LCE/CSNP monolayer and bilayer under DMA isostrain condition (pink and purple regions refer to the temperature ranges of LCE/CSNP monolayer and bilayer, respectively, under constant illumination). C Comparison of tip amplitude and frequency over a long time, where the undulation frequency is defined as the buckling frequency. D Motion tracking with the angle change during the first two cycles at the input of 3.728 W/cm2 (green, cyan, and blue refer to left, middle, and right points of the defect region, while violet and purple refer to the midpoint and tip of Region III, respectively). E Amplitude adaptation to increasing input, calculated from the trajectory of the cantilever tip (white region for undulation, while pink region for oscillation; the maximum amplitude is the buckling amplitude in undulation or the oscillation amplitude in oscillation; the residual amplitude is the amplitude of the last complete swing before buckling in undulation, which does not exist in oscillation). F The undulation-oscillation bifurcation at the input of 5.494 W/cm2. G Average kinetic energy variation across the two bifurcation points.
