Soft Robotic Fabric Actuator With Elastic Bands for High Force and Bending Performance in Hand Exoskeletons

Abstract

In current designs soft robotic bending actuators, the need for high force capabilities is not adequately addressed. In this article, we present a new inflatable actuator that exploits textile manufacturing techniques, using an elastic band to improve both bend and force performance. At a pressure of 102 kPa, the index finger sized actuator exerts 24.8 N of force on the environment. It is also capable of a full 360 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^{\circ }$</tex-math></inline-formula> bending angle for pressures between 30 kPa and 102 kPa with a maximum bending stiffness of 288.4 N/m. We further demonstrate feasibility of this new actuator in a case study of an entirely fabric based soft robotic hand exoskeleton that increases robustness and user comfort. Our results suggest that textile robotics could provide an attractive solution in terms of the development of user-friendly hand exoskeletons.