Origami-based auxetic tunable Helmholtz resonator for noise control

In this paper, we propose an origami-based auxetic tunable Helmholtz resonator by controlling the volume of the cavity to allow a real-time tunability of the resonance frequency. The design is inspired by the waterbomb origami base, which expands when stretched and contracts when compressed. Such a foldable structure offers a wide range of volume variation, which corresponds to a larger frequency shift in the bandwidth of interest. Based on the design of the origami resonator, multi-physical models are established to understand and predict the parameters' effect on the device's behavior. After fabrication, experimental tests are conducted on physical prototypes to validate the models and illustrate the effectiveness of the concept.