Enertia Micro: Birdbath Resonator Gyroscopes Enertia Microsystems is an American startup specializing in the development and commercialization of ultra-high precision Micro-Electromechanical Systems (MEMS) gyroscopes. Enertia's primary technology is a birdbath resonator gyro (also known as a micro-hemispherical resonator gyro), which Enertia claims will bridge the performance gap between MEMS based gyroscopes and higher-performance alternatives. Enertia Micro: Birdbath Resonator Gyroscopes