Bio-Inspired Pneumatic Modular Actuator for Peristaltic Transport

Peristalsis, a biologically inspired mechanism, plays a crucial role in locomotion and material transport in living systems. While extensively studied in nature, its application in soft robotics for handling and transporting objects has seen progress but remains limited. This study presents a pneumatic modular actuator, fabricated from silicone polymer, that is scalable, adaptable, and repairable in situ. The system integrates donut-shaped actuation modules capable of radial and axial inflation, coupled with real-time pressure feedback for synchronized control across multiple stacked modules. Experimental validation demonstrates the actuator's ability to grasp and transport objects with diameters as small as 0.4 times its inner diameter at a speed of $2.08 \pm 0.07\ {\mathrm{mm/s}}$. The system successfully handles a range of object materials, including deformable soft tubes, solid handheld levels, and irregularly shaped bundles of pens. This work advances peristaltic actuation on object transportation, enabling safe and reliable manipulation of deformable and irregularly shaped materials across various applications, such as underwater specimen delivery and field robotics operations.