A Fabrication Free, 3D Printed, Multi-Material, Self-Sensing Soft Actuator

Soft robotics offers a range of attractive features relative to traditional rigid robots, including inherently safer human-robot interactions, and continuous passive dynamics that enable morphological computation. Here we present an actuator with an integrated print-in-place strain sensor which is produced entirely via multi-material additive manufacturing and requires no post processing or manual fabrication steps. One natural application of this technology is the end effector of robotic arms; incorporating deformable actuators into a gripping mechanism allows for the safe integration of robotic assistance in human-occupied settings. While numerous soft robot actuators have been implemented without feedback, force sensing and proprioception are valuable signals to leverage in extending the capabilities of these systems. Prior approaches to integrating sensors into soft robot components have relied on manual processes, or specialized fabrication tools. Our work shows a novel method for automatically manufacturing soft pneumatically-driven actuators with embedded sensors through readily available 3D printing tools with no human fabrication required. Automatically manufacturing these sensor-actuator systems enables more complex, capable, and integrate-able designs, because the labor of assembly is eliminated; actuator-sensor designs that would be tedious or impossible to manufacture become tractable with our approach.