Research On Dynamic Measurement Error Calibration System For Modulation Displacement Sensor

With the development of science and technology, dynamic measurement has beenpaid more and more attention. The accuracy of measuring system, especially withmechanical structure, will decrease in the process of actual use, so that it is necessary to berecalibrated. Most of the calibration system developed by the standard instrumentmanufacturer or testing institution for a particular sensor, are single system and closed, cannot be other instruments. The purpose of this topic is: designing a dynamic measurementerror calibration system for modulation displacement sensor, supported by the NationalNatural Science Foundation. The main research contents as follows:1) Base on dynamic measurement theory and sensor calibration principle and method, analyzing the different schemes for error separation and correction, decided to use the ratiomethod and the method of least squares.2) Presenting a general scheme of dynamic measurement error calibration system formodulation displacement sensor. This scheme choose high accuracy grating as criterioninstrument. Setting FPGA as signal processor which faces not only grating signal but alsomodulation signal.3) Hardware of next-bit machine is designed, including instrumentation amplifier、band-pass Filter、active band filters、waveform converting circuit and so on. Software ofnext-bit machine is designed, including grating signal processing module and modulationprocessing module.4) This paper completed the development and design of the host computer procedureunder the environment of VC++. Aiming at the problem of error processing, used methodof mixed programming between Visual C++and MATLAB.5) Testing and Error analyzing of the dynamic measurement error calibration system, and point out the improved direction.The results of experiment show that dynamic measurement precision of modulationdisplacement sensor can be improved effectively. Compared with traditional calibrationsystem, this system can improve scientific institution’s efficiency, and reduce cost of testinginstitution.