UMArm: Untethered, Modular, Portable, Soft Pneumatic Arm

TL;DR

UMArm introduces a lightweight, untethered, and reconfigurable soft pneumatic robotic arm with integrated actuators, enabling high payload, precision, and adaptability in unstructured environments, suitable for wearable and robotic applications.

Contribution

This work presents a novel hybrid pneumatic arm with integrated valves and controllers, eliminating external regulators and enhancing portability, payload, and precision over existing soft robotic arms.

Findings

Achieved full untethered operation with high payload capacity.

Demonstrated portability through wearable assistive arm experiments.

Showcased reconfigurability by transforming into an inchworm robot.

Abstract

Robotic arms are essential to modern industries, however, their adaptability to unstructured environments remains limited. Soft robotic arms, particularly those actuated pneumatically, offer greater adaptability in unstructured environments and enhanced safety for human-robot interaction. However, current pneumatic soft arms are constrained by limited degrees of freedom, precision, payload capacity, and reliance on bulky external pressure regulators. In this work, a novel pneumatically driven rigid-soft hybrid arm, ``UMArm'', is presented. The shortcomings of pneumatically actuated soft arms are addressed by densely integrating high-force-to-weight-ratio, self-regulated McKibben actuators onto a lightweight rigid spine structure. The modified McKibben actuators incorporate valves and controllers directly inside, eliminating the need for individual pressure lines and external regulators, significantly reducing system weight and complexity. Full untethered operation, high payload capacity, precision, and directionally tunable compliance are achieved by the UMArm. Portability is demonstrated through a wearable assistive arm experiment, and versatility is showcased by reconfiguring the system into an inchworm robot. The results of this work show that the high-degree-of-freedom, external-regulator-free pneumatically driven arm systems like the UMArm possess great potential for real-world unstructured environments.