Versatile and Robust Soft Untethered Robots with Tight Integration of Soft Actuators and Flex Circuitry that Navigating Through Unstructured Terrains

Soft legged robots require robust walking dynamics and untethered functionality to approach the capability of their natural mammalian and reptilian counterparts to swiftly maneuver through unstructured environments. Achieving a soft robotics platform capable of biologically-relevant locomotion speeds depends on careful selection of actuators and electronics with soft materials and integration of power and control electronics. We demonstrate this with two untethered soft robotic testbeds that are both composed of flexible printed circuit board that integrates power and control electronics and electrically-powered soft limbs. The first implementation is a quadruped that is capable of walking at a maximum speed of 0.56 body length per second (3.2cm/s) and making 90 degree turns in two complete gait cycles (~5s). The second is a caterpillar-inspired robot capable of crawling with multiple gait at a speed of ~10mm/s over 25min. These robots are versatile and robust and have the capability of walking on a variety of surfaces, including up inclines, rocky terrain and poppy seeds, climbing over a half body height step, and maintaining continuous forward locomotion through confined space or after being dropped from an elevated height.