3D Elastomeric Kirigami for Passively Stretchable Fully Soft Vacuum‐Powered Artificial Muscles

In this article, inspired by the classic 2D kirigami art that achieves diverse deformation through cutting operations on layered materials, a passively stretchable and fully soft vacuum powered artificial muscle (VPAM) based on a 3D elastomeric kirigami structure (here called kiri‐elastomer VPAM) is proposed. The kiri‐elastomer VPAM is constructed almost entirely from one soft material, which ensures good flexibility for the actuator. Meanwhile, the three‐dimensional kiri‐elastomer design provides the VPAM with the ability to passively stretch and actively contract, which is consistent with the deformation mode of biological muscles. Experiments have been conducted to investigate the static and dynamic characteristics of this type of VPAM. The experimental results show that the maximum output strain and stress measured from the experimental prototypes are 74.1% and 0.044 MPa. Besides, the dynamic characterization experiments have shown that the volumetric energy density and the maximum specific power of these artificial muscles reach 14 kJ/m3 and 316 W/kg, respectively, which are higher than the typical value of human skeleton muscles, implying good potential application values of these actuators. Then, the application demonstrations including lifting weights and antagonistic actuation have been conducted to show the passive stretchability, scalability and applicability of the kiri‐elastomer VPAM.