Magnetoactuated Reconfigurable Antennas on Hard-Magnetic Soft Substrates and E-Threads

We report new classes of reconfigurable antennas realized by embedding conductive e-threads inside programmable hard-magnetic soft substrates. Antenna deformations that rely on magnetic actuation are a promising alternative to conventional complicated and labor-intensive reconfiguration approaches due to their design, fabrication, and operation simplicity. However, state-of-the-art magnetoactuated approaches rely on soft-magnetic materials that suffer from stress failure, exhibit limited degrees of freedom, and do not allow programmable polarity deformations. Our work overcomes these challenges. By embedding NdFeB particles in soft silicone and by further coating e-thread antennas with the resulting flexible material, novel prototypes are brought forward that allow programmable polarity, stable magnetic properties, untethered actuation, response speed that could not be captured with high-speed camera (60 frames/s), reversible deformation, light weight, and extreme mechanical/thermal tolerance. In this article, we introduce the operating principle of this new class of antennas, optimize their fabrication, and validate them numerically and experimentally. As a proof-of-concept, validation is carried out for an accordion-based monopole, tunable from 680 to 835 MHz when actuated by a remote magnet. In future, this approach can be leveraged toward diverse reconfigurable antennas in consumer and defense applications.