Flexible static supporting accelerometer

Abstract

The invention relates to a flexible static supporting accelerometer. The accelerometer comprises a sensitive meter core component, a base, a shell, a temperature testing module and a sealing ring component. The sensitive meter core component is composed of an upper counter electrode plate, a lower counter electrode plate and a quartz pendulous reed; a gold membrane of the quartz pendulous reed isused as a capacitance electrode plate, and the gold membrane of the quartz pendulous reed and gold membranes of the upper counter electrode plate and the lower counter electrode plate form a pair of force application capacitors and a pair of differential detection capacitors. The upper counter electrode plate, the lower counter electrode plate and the quartz pendulous reed are coaxially installedthrough a mirror image and brazed, and the quartz pendulous reed is fixedly installed between the upper counter electrode plate and the lower counter electrode plate. A capacitor displacement circuit,a fedback control circuit and a static electricity feedback execution circuit complete detection on the differential capacitors and feedback control over the accelerometer, and finally the inspectionquality is moved to the equilibrium position. The interior of a surface body is vacuumized, and hot noise caused by Brownian movement of gas molecules is reduced. Through design of a low-dilatation-coefficient material, differential capacitor detection and static electricity force application, the accelerometer is simple in structure, high in stability and low in noise and is widely applied to tasks with high-precision measurement demands. The accelerometer is suitable of the field of microquake measurement, resource detection and physical geography and particularly suitable for inertial systems for measurement on the horizontal tensor of a gravity gradient instrument or orbital transfer of low-range space satellites and the like.

Description

technical field [0001] The invention relates to the technical field of sensors, in particular to a quartz flexible electrostatic support accelerometer that maintains high stability and low noise output for a long time within a small range, and is suitable for microseismic measurement, resource detection, and geophysical fields, especially for gravity Inertial systems such as gradiometer horizontal tensor measurement or low-range space satellite orbit change. Background technique [0002] An accelerometer is an instrument for measuring acceleration, which is of great significance in the fields of microseismic measurement, resource detection, and geophysics. At present, high-precision accelerometers can be roughly divided into two categories according to the feedback method: one is the electromagnetic force feedback accelerometer, and the other is the electrostatic force feedback accelerometer. [0003] At present, in the fields of gravity gradiometer horizontal tensor measur...

AI Technical Summary

Problems solved by technology

When the temperature changes, the quartz pendulum and the coil will be distorted, causing the capacitance difference or the change of the torque current, which will affect the temperature stability of the accelerometer output;

[0006] ⑵. The change of the magnetic field of the permanent magnet with time limits the long-term stability of the accelerometer output;

[0007] ⑶. Acceleration changes cause torque current changes, which will magnetize or demagnetize the permanent magnets, causing nonlinearity in the output of the accelerometer;

[0008] ⑷. A large number of enameled wires and bonding assembly processes are used inside the accelerometer. Various gases volatilized by enameled wires and adhesives cannot maintain the long-term vacuum inside the meter body, and cannot reduce and maintain the output noise of the accelerometer.

[0011] ⑴. The measuring range is only a few μg, and the whole instrument is not suitable for land-based environment

[0012] ⑵. The noise in the published accelerometers is higher than 1ng / √Hz

The quartz electrostatic accelerometer based on MEMS is affected by the process, the inspection quality cannot be made very large, and the noise cannot be further reduced

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