A Miniature, 3D-Printed, Walking Robot With Soft Joints

Abstract

Miniature robots have many applications ranging from military surveillance to search and rescue in disaster areas. Nevertheless, the fabrication of such robots has traditionally been labor-intensive and time-consuming. This paper proposes to directly leverage multi-material 3D printing (MM3P) to fabricate centimeter-scale robots by utilizing soft materials to create soft joints in replacement of revolute joints. We demonstrate the capability of MM3P by creating a miniature, four-legged walking robot. Moreover, we establish a numerical method based on the Psuedorigid-Body (PRB) 1R model to predict the motion of the leg mechanism with multiple soft joints. Experimental results verify the proposed numerical method. Meanwhile, a functional walking robot actuated by a single DC motor is demonstrated with a locomotion speed of one body length/sec. The proposed design, fabrication, and analysis for the walking robot can be readily applied to other robots that have mechanisms with soft joints.