All-3D-Printed Multi-Environment Modular Microrobots Powered by Large-Displacement Dielectric Elastomer Microactuators.

Microrobots are expected to push the boundaries of robotics by enabling navigation in confined and cluttered environments due to their sub-centimeter scale. However, most microrobots perform best only in the specific conditions for which they are designed and require complete redesign and fabrication to adapt to new tasks and environments. Here, fully 3D-printed modular microrobots capable of performing a broad range of tasks across diverse environments are introduced. For multi-environment navigation, large-displacement dielectric elastomer microactuators with a soft-stiff hybrid structure are developed, capable of powering microrobots to stride over obstacles on various terrestrial terrain and rapidly propel themselves across aquatic terrain. To further expand their capabilities beyond mere navigation, ten task-specific modules for the microrobots are developed. All modules are fabricated using a digital light processing multimaterial 3D printer capable of simultaneously printing multiple photocurable resins, providing a broadly applicable platform for fabricating mesoscale robotic components. The microrobots navigate across smooth, rough, granular, and aquatic environments, demonstrating tasks such as controlling the movements of nearby robots, interacting with humans to avoid collisions, and collaboratively dragging heavy objects through multi-unit operation. The study addresses key limitations hindering the integration of modular design into microrobots, enabling adaptation to new environments and tasks.