Harnessing Symmetry Breaking in Soft Robotics: A Novel Approach for Underactuated Fingers

Soft robotics, an emerging domain in modern robotics, introduces innovative possibilities alongside challenges in controllability, particularly with multi-degree inflatable actuators. We present a novel manipulation method using underactuated soft fingers that addresses these challenges by harnessing symmetry breaking. Central to our approach is the mechanism of self-organization within a ring actuator equipped with five fingers. Typically considered a drawback, we exploit the actuator’s buckling behavior to facilitate in-hand manipulation. This strategic utilization enables object motion in both clockwise and counterclockwise directions via system perturbations and adjustments in frequency and duty cycle parameters. Employing the self-organizing properties of our actuator, our method is empirically validated through simulations and real actuator experiments, demonstrating the system’s ability in manipulating objects by leveraging the inherent flexibility and morphological advantages. The design enables two degrees of freedom with minimal input, allowing objects to rotate due to the actuator’s self-organizing actions. This simplification of control mechanisms is essential for soft robotics manipulation. Our findings indicate that control systems in soft robotics can be significantly simplified, harnessing the adaptable behavior inherent in its morphology.