Study Of Key Parameters Calibration For Heterodyne Laser Vibrometers

Laser vibrometers are widely used in national defense,precision machinery manufacturing,automotive and other fields.It is of prime importance to study their calibration techniques and methods.Research on this subject attached to the National Key Scientific Instrument and Equipment Development Projects “Cross-scale three-dimensional vibration measuring instrument measurement and evaluation of reliability”.This subject is responsible for the key parameters calibration for Heterodyne Laser Vibrometers,including calibration methods,standard equipments and calibration software.Eventually,a calibration system for the key parameters calibration of Heterodyne Laser Vibrometers is formed.Considering the application scope of this subject,the author mainly study the calibration of laser vibrometers' signal acquisition and processing circuit,within the vibration frequency of 0.2Hz to 300 kHz.The main research work carried out in the following areas:The first chapter,the background and significance of the subject were described,and the current calibration researches of laser vibrometers were reviewed,in addition,the main contents of the paper were outlined.The second chapter,six key parameters of laser vibrometer: range,linearity,sensitivity,phase shift,rising time,total harmonic distortion degree were determined.The definition and calibration methods of each parameter were studied to develop a electric signal calibration program for the key parameters of the laser vibrometer.The third chapter,completed the hardware selection and design of the laser vibrometer calibration system,introduced the design of signal module,data acquisition module and data processing and control module design,completed the building of the calibration device by using NI PXI platform.The fourth chapter,realized the software design of laser vibrometer calibration system,introduced the software program of user login module and key parameters calibration module based on LabVIEW.The communication and data acquisition and processing between PC and card equipment were realized by programming.Finally,the automatic calibration of the key parameters of laser vibrometer were realized.The fifth chapter,the performance of the calibration system developed in this paper were verified,and key parameters of Laser Doppler vibrometer LV-S01 were calibrated by using this calibration system,which verified the stability and accuracy of the calibration system.The sixth chapter is the conclusion of the full paper,pointed out the shortcomings,and put forward the prospect of the next step.