Contractile Actuators for Edible Robots

Muscle contraction is the driving mechanism of animal movement. In contrast to biological muscles, current artificial contractile actuators are not made of biodegradable and edible because they require negative pressure or complex fabrication processes. Here we present an edible contractile actuator that can be easily fabricated and operated using positive pressure. We characterize multiple edible materials with varying softness levels and analyze their influence on the actuator's contractile motion and force output. Furthermore, we introduce a novel storage method that enhances both contraction performance and force generation. We validate the function of the proposed actuator within a partially edible linkage structure that mimics a musculoskeletal system.