Abstract:
A microelectromechanical gyroscope (10) with detection along a vertical axis is provided with a detection structure (10) having a movable structure (12), suspended above a substrate (13) so as to perform, as a function of an angular velocity (Ωz) around the vertical axis a sense movement along a first horizontal axis (x). The movable structure has at least one drive mass (14) internally defining a window (16), elastically coupled to a rotor anchor (20'), at an anchoring region (A), through elastic anchoring elements (21); at least one bridge element (18), rigid and of a conductive material, cantilevered suspended and extending within the window along the first horizontal axis, elastically coupled to the drive mass; movable electrodes (23), carried integrally by the bridge element with extension along a second horizontal axis (y). The detection structure (10) also has stator electrodes (28, 29), arranged in the window and interdigitated with the movable electrodes, at a certain separation distance below the bridge element (18), which extends longitudinally above the same stator electrodes and the movable electrodes.
Abstract:
A microelectromechanical gyroscope includes: the support structure (6); a sensing mass (3), coupled to the support structure (6) with degrees of freedom along a driving direction (DD) and a sensing direction (DS) perpendicular to each other; and a calibration structure (5) facing the sensing mass (3) and separated from the sensing mass (3) by a gap (21) having an average width (W), the calibration structure (5) being movable with respect to the sensing mass (3) so that displacements of the calibration structure (5) cause variations in the average width (W) of the gap (21) . A calibration actuator (20, 30) controls a relative position of the calibration structure (5) with respect to the sensing mass (3) and the average width (W) of the gap (21).
Abstract:
A micromechanical detection structure (20) comprises: a substrate (2) of semiconductor material; a driving-mass arrangement (4a-4c), coupled to a set of driving electrodes (7a-7c) and driven in a driving movement following upon biasing of the set of driving electrodes; a first anchorage unit (5a-5c, 6a-6c), coupled to the driving-mass arrangement for elastically coupling the driving-mass arrangement to the substrate (2) at first anchorages (5a-5c); a driven-mass arrangement (10, 30), elastically coupled to the driving-mass arrangement by a coupling unit (22a-22b) and designed to be driven by the driving movement; and a second anchorage unit (14, 34), coupled to the driven-mass arrangement for elastically coupling the driven-mass arrangement to the substrate (2) at second anchorages (17, 37). Following upon the driving movement, the resultant of the forces and of the torques exerted on the substrate (2) at the first and second anchorages is substantially zero.
Abstract:
A multi-axis MEMS gyroscope (42) is provided with a micromechanical detection structure (10) having: a substrate (12); a driving-mass arrangement (14a-14b); a driven-mass arrangement (20) with a central window (22); a sensing-mass arrangement (20; 35a-35b, 37a-37b), which undergoes sensing movements in the presence of angular velocities about a first horizontal axis (x) and a second horizontal axis (x); a sensing-electrode arrangement (29a-29b, 30a-30b), which is fixed with respect to the substrate and is set underneath the sensing-mass arrangement; and an anchorage assembly (24), set within the central window (22), for constraining the driven-mass arrangement to the substrate at anchorage elements (27). The anchorage assembly comprises a rigid structure (25a-25b), suspended above the substrate, elastically connected to the driven mass by elastic connection elements (26a-26b) at a central portion, and to the anchorage elements by elastic decoupling elements (28) at end portions thereof.
Abstract:
A micromechanical detection structure (20) comprises: a substrate (2) of semiconductor material; a driving-mass arrangement (4a-4c), coupled to a set of driving electrodes (7a-7c) and driven in a driving movement following upon biasing of the set of driving electrodes; a first anchorage unit (5a-5c, 6a-6c), coupled to the driving-mass arrangement for elastically coupling the driving-mass arrangement to the substrate (2) at first anchorages (5a-5c); a driven-mass arrangement (10, 30), elastically coupled to the driving-mass arrangement by a coupling unit (22a-22b) and designed to be driven by the driving movement; and a second anchorage unit (14, 34), coupled to the driven-mass arrangement for elastically coupling the driven-mass arrangement to the substrate (2) at second anchorages (17, 37). Following upon the driving movement, the resultant of the forces and of the torques exerted on the substrate (2) at the first and second anchorages is substantially zero.
Abstract:
MEMS gyroscope (350), having a first movable mass (303, 403) configured to move with respect to a fixed structure along a first drive direction and along a first sense direction, transverse to the first drive direction; a first drive assembly (310), coupled to the first movable mass and configured to generate a first alternate drive movement; a first drive elastic structure (320), coupled to the first movable mass and to the first drive assembly, rigid in the first drive direction and compliant in the first sense direction; a second movable mass (303, 403), configured to move with respect to the fixed structure in a second drive direction parallel to the first drive direction and in a second sense direction parallel to the first sense direction; a second drive assembly (311), coupled to the second movable mass and configured to generate a second alternate drive movement in the second drive direction; and a second drive elastic structure (320), coupled to the second movable mass and to the second drive assembly, rigid in the second drive direction and compliant in the second sense direction.
Abstract:
A MEMS angular rate sensor is presented with two pairs of suspended masses that are micromachined on a semiconductor layer. A first pair includes two masses opposite to and in mirror image of each other. The first pair of masses has driving structures to generate a mechanical oscillation in a linear direction. A second pair of masses includes two masses opposite to and in mirror image of each other. The second pair of masses is coupled to the first pair of driving masses with coupling elements. The two pairs of masses are coupled to a central bridge. The central bridge has a differential configuration to reject any external disturbances. Each of the masses of the two pairs of masses includes different portions to detect different linear and angular movements.
Abstract:
A MEMS based device (100) includes a phononic crystal body (130) formed from unit cells (131) and having a defect line (141) extending through the phononic crystal body. Unit cells inside of the defect line (141) lack a same phononic bandgap as the unit cells outside of the defect line. An input MEMS resonator (110) is mechanically coupled to a first end of the defect line, and an output MEMS resonator (150) is mechanically coupled to a second end of the defect line. Each of the unit cells (131) outside of the defect line has an identical geometry. The input MEMS resonator (110) and output MEMS resonator (150) each have a natural frequency within the same phononic bandgap possessed by the unit cells (131) outside of the defect line. There may be more than one defect line, and in such cases, the MEMS device may include more than one input MEMS resonator and/or more than one output MEMS resonator.
Abstract:
A microelectromechanical gyroscope (10) is provided with a detection structure (11) having: a substrate (14) with a top surface (14a) parallel to a horizontal plane (xy); a mobile mass (12), suspended above the substrate to perform, as a function of a first angular velocity (Ω x ) around a first axis (x) of the horizontal plane (xy), at least a first detection movement of rotation around a second axis (y) of the horizontal plane; and a first and a second stator elements (28a, 28b) integral with the substrate and arranged underneath the mobile mass to define a capacitive coupling, a capacitance value thereof is indicative of the first angular velocity (Ω x ). The detection structure has a single mechanical anchorage structure for anchoring both the mobile mass and the stator elements to the substrate, arranged internally with respect to the mobile mass, which is coupled to this single mechanical anchorage structure by coupling elastic elements (18) yielding to torsion around the second axis; the stator elements are integrally coupled to the single mechanical anchorage structure in an arrangement suspended above the top surface of the substrate.