Creating Shock-Resistant Sensors That Won’t Break Under Pressure
Research conducted by the Institute for NanoSystems Innovation on “Toward Enhanced Inertial Sensing via Dynamically Soft Topological States in Piezoelectric Microacoustic Metamaterials,” was published in Advanced Functional Materials, a top journal in materials science and engineering. This research was developed with funding from the Defense Advanced Research Projects Agency through the “Nimble Ultrafast Microsystems” (NIMBUS) program.
Abstract:
In recent decades, microelectromechanical systems (MEMS)-based gyroscopes have been widely employed for positioning and navigation in commercial devices. Most gyroscopes rely on electrostatic actuators with nanometer-scale air gaps—an architecture that enables large particle velocities in a proof mass and, consequently, high Coriolis-force sensitivity to angular velocity—but is inherently susceptible to damage under shock and vibration. This vulnerability is typically mitigated by purposely reducing gyroscopic sensitivity, thereby compromising readout accuracy. Microacoustic gyroscopes, by contrast, offer greater resilience to shock and vibration but currently exhibit significantly lower sensitivities. This limitation stems from the low dynamic compliance of the modes they employ—typically Lamb or Rayleigh modes—which restricts their maximum achievable particle velocity. This work presents a piezoelectric microacoustic device that overcomes this fundamental constraint by harnessing a topological interface state at the boundary between two microscale metamaterial structures. We theoretically and experimentally show that this state enables much higher modal compliance than Lamb or Rayleigh modes by leveraging its strong mode localization and the ability of its forming metamaterial structures to funnel energy directly into the localized modal region. This enables record-high particle velocities (>51 m/s) never reached by any previously demonstrated piezoelectric gyroscope because of material limits.
Related Faculty: Cristian Cassella , Siddhartha Ghosh , Luca Colombo , Benyamin Davaji , David Horsley
Related Departments:Electrical & Computer Engineering