Biasing Bending DEA-enabled Serial Kinematic thin Soft Robot for Locomotion and Manipulation in Confined Spaces

Soft robotics, actuated by smart materials and compliant mechanisms, offer significant potential for miniaturization, enabling deployment in confined spaces for inspection and maintenance tasks—areas where is a challenge for traditional robots. However, existing miniaturized soft robots generally exhibit limited locomotion modes, limiting their applicability in real-world scenarios. This research introduces a novel serial kinematic thin soft robot (SK-TS-Robot) featuring a biasing bending dielectric elastomer actuator (DEA) as active joint. The SK-TS-Robot comprises two thin soft robots (TS-Robot) connected by the basing bending DEA and is capable of five gaits. It is able to perform crawling, steering, climbing, transitioning, and manipulation in confined spaces. The biasing bending DEA, constructed with an elastic bending frame and four-layer dielectric elastomers, can bend up to 90° when unactuated and unfold to a flat state when actuated. The joint provides sufficient force to ensure effective transitioning and manipulation. Using this active joint, we demonstrated the SK-TS-Robot's ability to 'repair' an electric circuit, lighting an LED, and program Morse code 'SOS' through controllable joint actuation.