Wireless Miniature Magnetic Phase‐Change Soft Actuators

Abstract Wireless miniature soft actuators are promising for various potential high‐impact applications in medical, robotic grippers, and artificial muscles. However, these miniature soft actuators are currently constrained by a small output force and low work capacity. To address such challenges, a miniature magnetic phase‐change soft composite actuator is reported. This soft actuator exhibits an expanding deformation and enables up to a 70 N output force and 175.2 J g −1 work capacity under remote magnetic radio frequency heating, which are 10 6 –10 7 times that of traditional magnetic soft actuators. To demonstrate its capabilities, a wireless soft robotic device is first designed that can withstand 0.24 m s −1 fluid flows in an artery phantom. By integrating it with a thermally‐responsive shape‐memory polymer and bistable metamaterial sleeve, a wireless reversible bistable stent is designed toward future potential angioplasty applications. Moreover, it can additionally locomote inside and jump out of granular media. At last, the phase‐change actuator can realize programmable bending deformations when a specifically designed magnetization profile is encoded, enhancing its shape‐programming capability. Such a miniature soft actuator provides an approach to enhance the mechanical output and versatility of magnetic soft robots and devices, extending their medical and other potential applications.