Free beam vibration angle speed rate sensor

Abstract

The invention discloses a free beam vibration angle speed rate sensor. The free beam vibration angle speed rate sensor comprises a rectangle vibrating beam which is made of an elastic alloy material, wherein the vibrating beam is provided with a piezoelectric piece, the surface of the piezoelectric piece is provided with a binding post, and a vibration node of the vibrating beam is also provided with a structural support. The free beam vibration angle speed rate sensor is characterized in that the structural support comprises rod-shaped supporting beams which are perpendicularly arranged at the centre positions of four surfaces of the vibration node of the vibrating beam, and the four supporting beams form a cross-shaped support structure; and the position, at which the piezoelectric piece is arranged, on the vibrating beam is provided with an installation groove which is matched with the piezoelectric piece, the piezoelectric piece is inlaid and fixed in the installation groove, and the external surface of the piezoelectric piece and the surface of the vibrating beam are positioned in the same plane. The free beam vibration angle speed rate sensor disclosed by the invention has the advantages of small volume, low cost, high reliability and the like; and the system shock resistance and interference resistance are enhanced, and the system sensitivity is improved and the zero position stability is good.

Description

technical field [0001] The invention relates to the field of micro inertial measurement devices, in particular to a vibrating beam type vibration angular rate sensor. Background technique [0002] In recent years, with the development and progress of society, the micro-volume vibrating gyroscopes used in special environments have received widespread attention. For example, in the aspect of attitude measurement in underground or special environments on the ground; in recent years, with the decrease of mineral resources, the environment faced by the development of mineral resources is getting worse and worse, and its development is becoming more and more difficult, which requires the use of mineral resources. Inertial measurement devices (gyroscopes and accelerometers) for resource development should have good sensitivity, high impact resistance and anti-interference performance, and for example, directional drilling in mines or tunnels; real-time orientation control in compl...

AI Technical Summary

Problems solved by technology

[0003] The existing free-beam vibration angular rate sensor is a local vibration device. One of the traditional support methods is to adopt a double-node support structure design, such as the structure in an asynchronously driven piezoelectric vibration angular rate sensor disclosed in Patent No. 201020161061.3. This design satisfies the fact that the instantaneous linear momentum of the vibrating beam is zero under the fundamental frequency vibration, and the supporting beam at the ideal node fixes the vibrating beam, thus achieving a good mechanical isolation effect and effectively reducing the impact of external acceleration and environmental noise on the vibration of the vibrating beam The interference effect caused by it makes it have better anti-interference stability; the vibration angular rate sensor supported by double nodes has the above advantages, but also has two shortcomings: 1. In order to retain the advantages of node support, usually in The radius of the support beam installed at the node is made very small, which weakens the impact resistance of the gyroscope of this structure

2. Due to the asymmetry in the support structure of the double support beam support, after the support beam is installed, the frequency interval of the gyro as a whole when the driving surface and the sensitive surface resonate expands, which cannot meet the optimal interval frequency calculated by theoretical analysis. , bandwidth, and zero stability all affect

[0004] Another traditional support method is a surface support structure, such as the structure used in a vibrating beam gyro with double cantilever surface support structure disclosed in patent application No. 201010616509.0. However, it also brings many deficiencies: 1. The surface support method limits the freedom of all vibration nodes of the vibrating beam at the installation site. Since the vibration beam has a thickness, the surface support structure limits the installation site. The maximum rotation angle, which in turn affects the vibration amplitude of the vibration beam, thus reducing the system sensitivity

2. After the surface support structure is installed, the resonant frequency of the driving surface and the sensitive surface of the overall gyro has greatly increased compared with the resonant frequency of the free vibrating beam in both directions, which brings difficulty in finding a suitable driving frequency. At the same time, the overall system has inherent The increase in frequency will cause instability to the zero position of this type of gyroscope

3. The surface support structure is installed at the ideal node of the non-vibrating beam, so the system must be sensitive to the acceleration of the substrate and external interference through the support structure, which increases the detection error and reduces the measurement accuracy

Insufficient support methods above reduce the performance of the free beam vibration angular rate sensor

[0005] In addition, for the traditional free-beam vibration angular rate sensors under the above two different support methods, the structure of the piezoelectric sheet is directly pasted on the surface of the vibrating beam through glue, which is affected by the paste error; As the temperature rises, the adhesion coefficient of the glue decreases, and it is easy to age, which will affect the reliability and output sensitivity of the system.

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