Characterization of a novel micromachined optical vibrating rate gyroscope

The present article presents experimental results measured on a new class o f micromachined rate-gyroscope, incorporating integrated optical sensing. A hybrid cantilever type device was fabricated by bulk micromachining, bonde d to a complementary metal-oxide-semiconductor chip and encapsulated in a v acuum package. The proof mass is electrostatically actuated and the mechani cal output motion is sensed by modulated integrative differential optical s ensing method. Characterization of the device, including measurements of th e natural frequencies and angular rate, is reported. Noise measurements ind icate noise equivalent rate of 10(-2)-10(-3) deg/s/root Hz. Currently the m easured minimum detectable rate is 1 deg/s due to experimental setup limita tions. (C) 1999 American Institute of Physics. [S0034-6748(99)00602-4].