Jellyfish-inspired non-reciprocal light-fueled self-propelling liquid crystal elastomer-based fluidic saucer

Self-sustained oscillators can generate periodic motion under continuous stimulation. Most reported systems exhibit reciprocating motion, where the propulsive thrusts in opposite directions partially cancel each other, thus limiting their efficiency in achieving non-reciprocal propulsion. Inspired by jellyfish pulsatile jet propulsion, this study proposes a light-fueled fluidic saucer that realizes non-reciprocal bursting and propulsion through the coordinated coupling between a self-rotating liquid crystal elastomer torus structural backbone and a self-snapping liquid crystal elastomer spherical shell engine. The torus continuously drives the shell's snap-through in a single direction. Based on the photothermally responsive liquid crystal elastomer model, we derive the governing equations and characterize the dynamics. The results reveal two typical motion modes of the light-fueled fluidic saucer: braking mode and propulsive mode. Under constant illumination, the light-fueled fluidic saucer alternates between these modes to realize non-reciprocal self-propelling in fluid environment. In addition, the critical conditions for mode switching are determined. The light-fueled fluidic saucer's activation threshold and motion period can be controlled by adjusting contraction coefficient, geometric parameter, and power density per unit mass. We further analyze the velocity and the period of self-propelling. The proposed non-reciprocal self-propelling light-fueled fluidic saucer, characterized by its controllable period, electronics-free operation, and non-reciprocal motion, utilizes a non-contact, light-driven mechanism to enable programmable and tunable periodic responses, providing a conceptual design and theoretical guidance for applications such as stratospheric micro-vehicles, environmental probes, and autonomous robotics.