Numerical Modeling of Photothermal Self‐Excited Composite Oscillators

Autonomous motion, such as self‐excited oscillation, emerges from the intricate interaction between structural deformation and external stimulation. By carefully engineering this interaction, diverse modes of locomotion have been achieved without the need for real‐time human control or external intervention. However, quantitatively capturing and modeling such behavior inevitably require solving a set of highly coupled equations across multiple physical fields. In this study, we develop a numerical framework for simulating photothermal self‐excited composite oscillators, which couples the light‐heat conversion, the heat transfer within the composite, and thermal strain‐induced large deformation. We systematically study the influence of various operating conditions and material properties on oscillation and establish the criteria and conditions for the onset of self‐excited oscillation. This study aims to provide design guidelines for future autonomous actuators and robotic systems.