Research 

Exposure to loud noises can cause hearing loss, stress, and communication problems. Active noise cancelling piezo - electric materials, passive foams/foam-like materials and acoustic metamaterials (near-zero, single negative, double negative) are common forms of noise dampening alternatives currently in use, although each has its own set of drawbacks. For the passive foam materials, for instance, weight and volume are issues because they are quite heavy and occupy very high level of space. Certain vehicles, like aircrafts, may have heavy foam put inside them, which is a major reason of increased fuel consumption and decreased operational efficiency. Although piezo-based systems may be lighter or smaller than foams, they still need control hardware, circuits, power supply etc. These materials frequently exhibit poor sound absorption properties particularly in the low frequency range, necessitating the use of thicker structures with dimensions corresponding to the working wavelength of acoustic signals. For particular applications, such as damping within aircrafts the component sizes and weights are rigorously restricted and the noise damper structures may be overtly thick or heavy and thus an engineering tradeoff between noise absorption, volume occupancy and weight addition leads to a very challenging situation There is a need in the aerospace industry for a lightweight, thin, high sound-absorbing material. Many solutions like passive and active meta-materials are realized for catering to these challenges. Most sub-wavelength acoustic absorbers exhibit good sound absorption in a specific frequency band, however the difficulty with that type of structure is that it is not adaptive to band shifting once it is created. Many researchers were drawn to examine the integration of SMPs (Shape-memory polymer) materials in acoustic meta-structure because of the ability to change physical properties with external inputs. Therefore, it is intriguing to think that a new generation of "auto-reconfigurable" AMMs may soon appear, offering performance far superior to the state of the art and enabling novel wave functionalities like broadband cloaking, tunable focusing, dynamic signal processing, and programmable analogue computing.

We focused our efforts in this work on creating, realizing, characterizing, and applying the concept of metamaterials to two separate aspects of science and technology. In one domain, we aim for sound reduction without air circulation by employing a back plate that does not allow acoustic air to pass through. In the other domain, we have created some new designs of 1D and 2D ventilated acoustic metamaterials with air circulation that absorb sound while also allowing acoustic air to travel through. All of the unique metamaterial designs were created utilizing a 3D printing machine using fused filament fabrication (FFF) procedure.