UCLA

Piezoelectric hydrophones are crucial in underwater applications, which include underwater communication or seafloor mapping. Limited by the brittleness of piezoelectric ceramics, conventional manufacturing methods are restricted to hydrophone elements with simple geometries such as disk, cube, or cylinder which restricts the sensitivity, directivity patterns, and working frequency bandwidth. This Master’s thesis demonstrates a way to fabricate 3D architected micro-lattices with Micro Stereolithography. High sensitivities for low frequencies are enabled by the high Figure of Merit of the fabricated micro architected piezoelectric elements. These lattices, which benefit from tunable sensitivities, also allow the fabrication of directional hydrophones for higher frequency applications. A framework to generate hydrophones with two or three-dimensional beam patterns is developed and verified with a series of experiments that demonstrate the potential applications of architected functional materials for underwater sound source detection or sound communication isolation.