Hybrid Soft Robots Incorporating Soft and Stiff Elements
This work addresses the problem of enabling more versatile and practical soft robots for applications requiring decoupled stiffness and shape control, representing an incremental improvement in soft robotics.
The paper tackles the limited stiffness range and coupled control in soft robots by proposing a hybrid soft robot design inspired by spider monkeys' tails, resulting in a 100% stiffness range increase compared to previous designs and demonstrating independent stiffness and shape control in a gripper application.
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.