MDOF (multi-degree of freedom) differential capacitance displacement sensor calibration device

Abstract

The invention discloses an MDOF (multi-degree of freedom) differential capacitance displacement sensor calibration device. The device comprises a differential capacitance displacement sensing module, a laser interferometry ranging module, a temperature control module and a data processing module, wherein the differential capacitance displacement sensing module comprises a mechanical sensitive probe and a differential capacitance sensing circuit; the mechanical sensitive probe comprises a movable polar plate, an MDOF micrometric displacement table, fixed polar plates and an insulating base; the laser interferometry ranging module comprises a laser, a shielding frame and N interference fringe units distributed in the translation DOF direction; the temperature control module is used for shielding disturbance of outside environment temperature; the laser interferometry ranging module measures displacement of the movable polar plate relative to the fixed polar plates, the differential capacitance displacement sensing module outputs a voltage signal, and a data acquisition and processing system processes data to obtain a scale coefficient when the movable polar plate moves to output voltage of the differential capacitance displacement sensing module in a translation DOF manner, so that the resolution level of the high-precision differential capacitance displacement sensing module with a micron-dimension range is accurately evaluated.

Description

technical field [0001] The invention belongs to the field of high-precision capacitive displacement sensor calibration, and more specifically relates to a multi-degree-of-freedom differential capacitive displacement sensor calibration device. Background technique [0002] As a traditional non-contact sensor, capacitive displacement sensor is mainly used in the measurement of displacement, angle, vibration, acceleration and pressure. The use of differential capacitance structure can greatly improve the resolution level of the sensor and reduce the influence of parasitic capacitance. However, as a relative measurement sensor, it needs to accurately calibrate its grid value coefficient before it can be used to measure displacement signals. Traditional mechanical calibration methods and calibration The device cannot meet the demand index of this kind of high-resolution and small-range differential capacitive displacement sensing module. [0003] The differential capacitive disp...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a multi-degree-of-freedom differential capacitive displacement sensor calibration device, aiming to solve the technical problem of calibrating a high-precision differential capacitive displacement sensor module with a measurement accuracy of picometer level and a range of micron level

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