Micro-machined gyrometric sensor for differential measurement of the movement of vibrating masses

Abstract

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 (') that are coupled by a coupling structure (). Each of the two assemblies comprises a moving mass () surrounded by a moving intermediate frame (). The frame () is connected to the coupling structure () and can vibrate in two degrees of freedom in orthogonal directions Ox and Oy of the plane of the wafer. The mass () is connected, on one side, to the frame and, on the other side, to fixed anchoring regions () via linking means (--) 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 () is associated with the frame in order to excite its vibration along Ox. A movement detection structure () is associated with the mass () in order to detect its vibration along Oy.