A method of detecting motion provides a resonator having a mass, moves the mass in a translational mode, and actuates the mass in a given bulk mode. The mass moves in the translational and given bulk modes at substantially the same time and, accordingly, the resonator is configured to detect linear and rotational movement when moving and actuating the mass in the translational and given bulk modes. The method produces one or more movement signals representing the detected linear and rotational movement.

Methods and apparatus for sensing linear acceleration with a MEMS resonator mass, alone, or concurrently with sensing rate of rotation. A resonator mass, which may be a disk or a ring structure, is driven at a resonance frequency of one of the vibration modes of the resonator mass. The amplitude of vibration of that mode is sensed by a set of at least two drive-sense electrodes disposed at opposing positions across the resonator mass. A linear acceleration is derived based at least on a difference between signals of the opposing electrodes. Linear acceleration may be sensed in multiple orthogonal dimensions using multiple pairs of opposing electrodes. Rotation rate may be derived concurrently by sensing the energy coupled into an orthogonal mode of the resonator mass.

Methods and apparatus for sensing linear acceleration with a MEMS resonator mass, alone, or concurrently with sensing rate of rotation. A resonator mass, which may be a disk or a ring structure, is driven at a resonance frequency of one of the vibration modes of the resonator mass. The amplitude of vibration of that mode is sensed by a set of at least two drive-sense electrodes disposed at opposing positions across the resonator mass. A linear acceleration is derived based at least on a difference between signals of the opposing electrodes. Linear acceleration may be sensed in multiple orthogonal dimensions using multiple pairs of opposing electrodes. Rotation rate may be derived concurrently by sensing the energy coupled into an orthogonal mode of the resonator mass.

A BAW gyroscope is configured to operate with two pairs of orthogonal modes instead of a single pair in order to mitigate the impact of changes in gaps (e.g., introduced from external stresses such as thermal gradients, external shocks, mechanical stress/torque, etc.). Specifically, the BAW gyroscope resonator is configured to be simultaneously driven to resonate with a two disparate resonant modes (referred to herein as the fundamental mode and the compound mode), with the same set of drive electrodes used to drive both resonant modes (i.e., all of the drive electrodes are used to drive the two drive modes). When the sensor experiences external rotation, energy couples from the driven modes of vibration to two corresponding orthogonal sense modes via the Coriolis force. The same set of sense electrodes is used to sense both sense modes (i.e., all of the sense electrodes are used to sense the two sense modes). The fundamental mode is differential with respect to the electrodes, while the compound mode is seen as common-mode with respect to the electrodes. Thus, differential gap change will impact offset of rate measured with the fundamental mode only, while common-mode gap change will impact offset of rate measured with the compound mode only.

A BAW gyroscope is configured to operate with two pairs of orthogonal modes instead of a single pair in order to mitigate the impact of changes in gaps (e.g., introduced from external stresses such as thermal gradients, external shocks, mechanical stress/torque, etc.). Specifically, the BAW gyroscope resonator is configured to be simultaneously driven to resonate with a two disparate resonant modes (referred to herein as the fundamental mode and the compound mode), with the same set of drive electrodes used to drive both resonant modes (i.e., all of the drive electrodes are used to drive the two drive modes). When the sensor experiences external rotation, energy couples from the driven modes of vibration to two corresponding orthogonal sense modes via the Coriolis force. The same set of sense electrodes is used to sense both sense modes (i.e., all of the sense electrodes are used to sense the two sense modes). The fundamental mode is differential with respect to the electrodes, while the compound mode is seen as common-mode with respect to the electrodes. Thus, differential gap change will impact offset of rate measured with the fundamental mode only, while common-mode gap change will impact offset of rate measured with the compound mode only.

A resonator element of the monocrystalline 4H or 6H polytype of silicon carbide. A MEMS device including the resonator element and a substrate, wherein the resonator element and the substrate are not coplanar, and acoustic decoupling of the resonator element and the substrate is at least partially dependent upon a degree to which the resonator element and the substrate are not coplanar. A MEMS gyroscope including the resonator element, a substrate, one or more electrodes disposed proximate the resonator element, and a capacitive gap disposed between each electrode and the resonator element. A MEMS device including the resonator element having has a Q greater than 1,000,000, a phononic crystal substrate, and a gap disposed between a perimeter edge of the resonator element and the phononic crystal substrate, wherein acoustic decoupling of the resonator element and the phononic crystal substrate is at least partially dependent upon a size of the gap.

A resonator element of the monocrystalline 4H or 6H polytype of silicon carbide. A MEMS device including the resonator element and a substrate, wherein the resonator element and the substrate are not coplanar, and acoustic decoupling of the resonator element and the substrate is at least partially dependent upon a degree to which the resonator element and the substrate are not coplanar. A MEMS gyroscope including the resonator element, a substrate, one or more electrodes disposed proximate the resonator element, and a capacitive gap disposed between each electrode and the resonator element. A MEMS device including the resonator element having has a Q greater than 1,000,000, a phononic crystal substrate, and a gap disposed between a perimeter edge of the resonator element and the phononic crystal substrate, wherein acoustic decoupling of the resonator element and the phononic crystal substrate is at least partially dependent upon a size of the gap.