Shape-programmable soft materials that exhibit integrated multifunctional shape manipulations, including reprogrammable, untethered, fast, and reversible shape transformation and locking, are highly desirable for a plethora of applications, including soft robotics, morphing structures, and biomedical devices.Despite recent progress, it remains challenging to achieve multiple shape manipulations in one material system. Here, we report a novel magnetic shape memory polymer composite to achieve this. The composite consists of two types of magnetic particles in an amorphous shape memory polymer matrix. The matrix softens via magnetic inductive heating of low-coercivity particles, and highremanence particles with reprogrammable magnetization profiles drive the rapid and reversible shape change under actuation magnetic fields. Once cooled, the actuated shape can be locked. Additionally, varying the particle loadings for heating enables sequential actuation. The integrated multifunctional shape manipulations are further exploited for applications including soft magnetic grippers with large grabbing force, sequential logic for computing, and reconfigurable antennas.

No abstract

No abstract

A novel broadband RHCP/LHCP reconfigurable patch antenna array using an E-shaped patch antenna element is investigated. By applying Particle Swarm Optimization, a 17% S11-AR bandwidth was achieved and verified through measurement for the isolated element using MEMS switches at an overall substrate thickness of 0.092λ0. The achieved bandwidth is significantly higher than the current state-of-the-art in single-layer, single feed CP patch element designs with similar substrate thickness. A small percentage of the upper frequency band experiences a pronounced beam squint similarly to other thick substrate CP patch antennas. To overcome the beam squint, a novel rotated-element configuration is implemented to force pattern symmetry. Derivations of pattern symmetry and network effects are also shown. The final design prototype using rotated elements provides a measured 20% S11-AR bandwidth with good radiation pattern stability.

No abstract