Inertial measurement module and three-axis accelerometer

Abstract

The present invention provides an inertial measurement module and a three-axis accelerometer, comprising a first pole piece located on a substrate, and a quality block suspended above the substrate through an elastic cross beam; the elastic cross beam includes a first elastic beam, The second elastic beam, the two ends of the second elastic beam are connected to the anchor point of the substrate, and the two ends of the first elastic beam are connected to the mass block; the center of the first elastic beam and / or the second elastic beam deviates from the center of the mass block center of gravity; the mass block is also provided with a first movable electrode and a second movable electrode in the direction of the Y-axis and the X-axis; the inertial measurement module of the present invention, a certain axis (X-axis, Y-axis) in the plane The movement will not be affected by the eccentricity of the structure, so that the movements of the X-axis and Y-axis are linear movements, so that the coupling between the axes will not be aggravated; on the other hand, the displacement of the mass block on the X-axis and Y-axis will not be reduced The amount improves the accuracy of capacitance detection.

Description

technical field [0001] The invention belongs to the field of micro-electro-mechanical (MEMS), more precisely, relates to a micro-electro-mechanical inertial measurement module, and the invention also relates to a three-axis accelerometer. Background technique [0002] MEMS accelerometer is an inertial device based on MEMS technology, which is used to measure the linear motion acceleration of object motion. It has the characteristics of small size, high reliability, low cost, suitable for mass production, etc., so it has broad market prospects, and its application fields include consumer electronics, aerospace, automobiles, medical equipment and weapons, etc. [0003] At present, there are usually two implementation methods for three-axis accelerometers. One is a patchwork method, which combines three single-axis structures or a dual-axis and a single-axis structure to realize the measurement of three axial accelerations. The second is to use a single structure to realize th...

AI Technical Summary

Problems solved by technology

In the single-structure implementation scheme, the z-axis acceleration is generally measured through the eccentric structure. In this scheme, in addition to the z-axis detection motion, the eccentric feature of the structure is used, and the detection motion of a certain axis (such as the x-axis or y-axis) in the plane is also It will be affected by the eccentric characteristics of the structure, so its motion is actually a swing rather than a linear motion. On the one hand, this motion will intensify the inter-axis coupling, and on the other hand, it will reduce the capacitance change, thus greatly reducing the detection accuracy.

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