Micro-Machined Gyrometric Sensor For Differential Measurement of the Movement of Vibrating Masses

• Main Authors: LE VERRIER BERTRAND, CHAUMET BERNARD, WILLEMIN JEROME, ROUGEOT CLAUDE
• Format: Patent
• Language: English
• Published: 04.09.2008
• Subjects: GYROSCOPIC INSTRUMENTS; MEASURING; MEASURING DISTANCES, LEVELS OR BEARINGS; NAVIGATION; PHOTOGRAMMETRY OR VIDEOGRAMMETRY; PHYSICS; SURVEYING; TESTING

The invention relates to a microgyroscope, that is to say an inertial micromechanical sensor dedicated to the measurement of angular velocities, which is produced by micromachining techniques, and has a novel arrangement of the modules for measuring the movement of the vibrating masses. The gyroscope comprises two symmetrical moving assemblies ( 30, 50; 30', 50 ') that are coupled by a coupling structure ( 20, 20', 22 ). Each of the two assemblies comprises a moving mass ( 30 ) surrounded by a moving intermediate frame ( 50 ). The frame ( 50 ) is connected to the coupling structure ( 20, 20', 22 ) and can vibrate in two degrees of freedom in orthogonal directions Ox and Oy of the plane of the wafer. The mass ( 30 ) is connected, on one side, to the frame and, on the other side, to fixed anchoring regions ( 34, 36 ) via linking means ( 40 - 46; 52 - 58 ) that allow the vibration movement in the Oy direction to be transmitted to the mass without permitting any movement of the mass in the Ox direction. An excitation structure ( 70 ) is associated with the frame in order to excite its vibration along Ox. A movement detection structure ( 90 ) is associated with the mass ( 30 ) in order to detect its vibration along Oy.