Novel touch-free drive, sense, and tuning mechanism for all-dielectric micro-shell gyroscope

Abstract

This paper demonstrates, for the first time, touch-free electrical sensing and frequency tuning of an all-dielectric micro-shell gyroscope without electrically-conductive coatings. Current vibratory gyroscope technologies rely on an electrically-conductive structure or conductive coatings [1-6]. These conductive materials and coatings often compromise the quality factor (Q), thermal stability, and symmetry necessary to achieve navigation grade performance. The novel mechanism presented herein is based on the manipulation of electric fringe fields and their gradients. Several highly-doped Si electrode structures placed adjacent to the micro-shell can drive, sense, and frequency-tune the micro-shell as experimentally demonstrated in this paper. Micro-shell n = 2 wineglass vibration modes with Q > 104 and frequency splits ∆f < 50Hz are experimentally demonstrated using the touch-free gradient field transduction mechanism. Tuning of up to 4 Hz is demonstrated for a modest bias of 20V.