Light-mediated communication in responsive materials ranging from individual self-oscillators to feedback-driven...

The natural interactive materials under far-from-equilibrium conditions have significantly inspired advances in synthetic biomimetic materials. In artificial systems, there are means of interaction between individuals, for instance, mechanical contact, hydrodynamic coupling, thermal gradient, chemical diffusion and magnetic field. However, they generally lack high directionality or sufficient interaction ranges. Here, we present a method for constructing highly directed, interactive structures via optical feedback in light responsive materials far from their thermodynamic equilibria. We showcase a photomechanical operator system comprising a baffle and a soft actuator. Positive and negative operators are configured to induce light-triggered deformations, alternately interrupting the passage of two light beams in a closed feedback loop. The fundamental functionalities of this optically interconnected material loop include homeostasis-like self-oscillation and signal transmission from one material to another via light. Refinements in optical alignment allow remote sensing and feedback networks capable of adaptation in both materials' shape-morphing states and oscillating frequencies. The results show a versatile design method for light-mediated interaction among responsive materials, with applicability in everyday materials.