Monolithic Desktop Digital Fabrication of Autonomous Walking Robots

Abstract

The fully automated fabrication of robots has long been a holy grail with the potential to revolutionize various industries, including manufacturing, construction, disaster relief, and space exploration. 3D printing offers a promising approach to automation, but the ability to print entire, complex robots with multiple materials remains limited. Previous approaches have simplified robot manufacturing by using fluidic control circuits, but these rely on labor‐intensive methods like silicone molding and manual assembly, limiting accessibility and replicability. Recent work, including this work, has demonstrated 3D‐printed robotic grippers and crawlers with embedded control circuits, but generating cyclic control outputs for legged locomotion in rough terrain remains challenging. This study addresses the challenge with a monolithic 3D‐printable four‐phase bistable oscillating valve, capable of generating coordinated motion of multiple limbs from a steady source of pressurized air. The ability of the oscillator to control an electronics‐free autonomous legged robot capable of walking on rough terrain, which can be fully fabricated on a desktop 3D printer without postassembly is demonstrated. The robot is operational immediately upon connection to an air supply. This development marks a significant step toward accessible, customizable, and biodegradable autonomous soft robots that can be produced using desktop 3D printers with no human intervention.