Fiber Bragg Grating Two-Dimensional Vibration Sensor with Adjustable Range

Abstract

The invention relates to a fiber grating two-dimensional vibration sensor with an adjustable measuring range. The fiber grating two-dimensional vibration sensor comprises a cylindrical and hollow base, the inner surface of the base is provided with a convex ring, a coaxial threaded round rod is fixed to the inner bottom surface of the base, the middle of the threaded round rod is sleeved by a pair of mass rings through screw-thread fit, a coaxial fiber fixing plate is fixed at the top end of the threaded round rod, a fiber grating is fixed on the fiber fixing plate and the convex ring, a first grating to a fourth grating are arranged on the fiber grating successively and are all located in the annulus space between the fiber fixing plate and the convex ring. When a certain point on the axis of the threaded round rod is used as an origin, a plane passing through the origin and perpendicular to the axis is defined as a coordinate plane. The first grating and the second grating are located in the X-axis direction, the third grating and the fourth grating are located in the Y-axis direction, and the pre-tightening forces of the first grating to the fourth grating are equal. The sensor uses a fiber grating as a sensing element, is high in measurement accuracy, can flexibly change sensitivity to adjust a measuring range, and eliminates the influence of the accidental factors.

Description

technical field [0001] The invention belongs to the technical field of vibration measurement, and in particular relates to a fiber grating two-dimensional vibration sensor with adjustable measuring range. Background technique [0002] There are two types of commonly used two-dimensional vibration acceleration sensors. One is the strain gauge type isoelectric vibration sensor. This type of sensor is susceptible to electromagnetic interference and cannot be measured accurately. Hidden danger. The other is the two-dimensional fiber grating vibration sensor. Although this type has the advantages of anti-electromagnetic interference, small size, low cost, and dynamic measurement, it has the following disadvantages: 1) In order to meet the accuracy requirements of the fiber grating, the fiber grating The measurement range of the fiber grating is relatively small. In order to adjust the measurement range of the fiber grating, it is necessary to be able to adjust the sensitivity of...

AI Technical Summary

Problems solved by technology

[0002] There are two types of commonly used two-dimensional vibration acceleration sensors. One is the strain gauge type isoelectric vibration sensor. This type of sensor is susceptible to electromagnetic interference and cannot be measured accurately. Hidden danger

The other is the two-dimensional fiber grating vibration sensor. Although this type has the advantages of anti-electromagnetic interference, small size, low cost, and dynamic measurement, it has the following disadvantages: 1) In order to meet the accuracy requirements of the fiber grating, the fiber grating The measurement range of the fiber grating is relatively small. In order to adjust the measurement range of the fiber grating, it is necessary to be able to adjust the sensitivity of the fiber grating at will, and to meet the accuracy requirements, select the appropriate sensitivity according to the range of the measurement range, so that the measurement range can be adjusted. , but at present, the sensitivity of fiber gratings is difficult to adjust at will; 2) the sensitivity of the two orthogonal directions of the two-dimensional plane is different, and the synthesized total acceleration value is not accurate enough; 3) accidental factors such as temperature will interfere with the measurement, making less precise measurements

Images