Hybrid Soft Robots Incorporating Soft and Stiff Elements

TL;DR

This paper introduces a hybrid soft robot inspired by spider monkeys, demonstrating a doubled stiffness range and independent control of shape and stiffness for safer, more versatile soft robotic applications.

Contribution

The paper presents a novel hybrid soft robot design that significantly increases controllable stiffness range and enables independent shape and stiffness control, advancing soft robot capabilities.

Findings

100% increase in stiffness range compared to previous designs

Successful independent control of shape and stiffness

Effective application in soft robotic gripper

Abstract

Soft robots are inherently compliant and have a strong potential to realize human-friendly and safe robots. Despite continued research highlighting the potential of soft robots, they remain largely confined to laboratory settings. In this work, inspired by spider monkeys' tails, we propose a hybrid soft robot (HSR) design. We detail the design objectives and methodology to improve the controllable stiffness range and achieve independent stiffness and shape control. We extend the curve parametric approach to We experimentally demonstrate that the proposed HSR has about a 100% stiffness range increase than a previous soft robot design with identical physical dimensions. In addition, we empirically map HSR's bending shape-pressure-stiffness and present an application example - a soft robotic gripper - to demonstrate the decoupled nature of stiffness and shape variations. Experimental results show that proposed HSR can be successfully used in applications where independent stiffness and shape control is desired.