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CN-121994726-A - Raman spectrum explosive identifier calibration method with self-adaptive environmental parameters

CN121994726ACN 121994726 ACN121994726 ACN 121994726ACN-121994726-A

Abstract

The invention belongs to the technical field of Raman spectrum, in particular to a Raman spectrum explosive identification instrument calibration method with self-adaptive environmental parameters, which comprises the following steps of constructing a Raman spectrum detection system, executing calibration, controlling a laser source to irradiate an internal standard substance module, and eliminating dependence on a real explosive sample by integrating the internal standard substance module in the identification instrument, wherein the light source irradiates a harmless internal standard substance during the calibration, thereby fundamentally eliminating safety risks and regulation barriers caused by storage and use of dangerous articles in public places, automatically triggering the calibration process when external conditions change, and quantifying and compensating drift of instrument core parameters caused by temperature drift, mechanical stress and the like in real time by using a wavelength-pixel coordinate correction relation established by polynomial fitting, ensuring that the wavelength coordinates output by the instrument are accurate in a field environment, and laying a solid foundation for follow-up accurate identification.

Inventors

  • XUE BIN

Assignees

  • 湖北鑫泽新材料科技有限公司

Dates

Publication Date
20260508
Application Date
20260202

Claims (10)

  1. 1. The method for calibrating the Raman spectrum explosive identifier with self-adaptive environmental parameters is characterized by comprising the following steps of: S1, constructing a Raman spectrum detection system, wherein the Raman spectrum detection system comprises a laser source, a beam splitter, a detector, a built-in standard substance module, a storage unit, a processing unit and an environment sensor module, wherein the storage unit is used for storing a standard Raman spectrum database and a calibration history database; s2, performing calibration, including: S21, controlling the laser source to irradiate a built-in standard module, wherein a calibration material which is known and has a stable characteristic Raman peak position is loaded in the built-in standard module; s22, collecting a first Raman spectrum generated by the calibration material through the detector and the beam splitter; S23, identifying actual measurement pixel coordinates of the calibration material in the first Raman spectrum; S24, comparing the actually measured pixel coordinates with standard Raman displacement in a standard Raman spectrum database, calculating a wavelength-pixel coordinate correction relation established under the current instrument working condition, and storing key parameters of the calibration into the calibration history database; s3, detecting the sample to be detected, including: s31, controlling the laser source to irradiate a sample to be detected; s32, collecting a second Raman spectrum generated by the sample to be detected; S33, correcting the pixel index of the second Raman spectrum by utilizing the wavelength-pixel coordinate correction relation established in the S24, generating spectrum data of wavelengths, and obtaining a corrected second Raman spectrum; s34, performing similarity calculation on the corrected second Raman spectrum and a reference spectrum in a standard Raman spectrum database to obtain similarity; S35, calculating the reliability score of the detection result based on the similarity and the real-time environmental parameters from the environmental sensor module and the data reliability evaluation model; S36, outputting the detection result and the corresponding reliability score.
  2. 2. The method for calibrating an environmental parameter-adaptive Raman spectrum explosive identifier according to claim 1, wherein in S2, the calibration material is a silicon wafer, and the standard Raman shift of the calibration material is 520.7 。
  3. 3. The method for calibrating an environmental parameter-adaptive Raman spectrum explosive identifier according to claim 2, wherein in S24, the method for establishing a wavelength-pixel coordinate correction relationship comprises: S241, data pair acquisition, and identifying a plurality of actual measurement pixel coordinates of the calibration material based on S23 Wherein Is the first Pixel positions of the characteristic peaks in the spectrum output by the current instrument working condition are measured based on a peak value searching algorithm; S242, curve fitting, namely, the actual measurement pixel coordinates And the standard characteristic wavelength Composed data pair Polynomial fitting is performed to obtain a correction polynomial function: ; Wherein, the Is the first Standard characteristic wavelengths of the individual characteristic peaks, the standard characteristic wavelengths being stored in a standard raman spectrum database; representing pixel indices for fitting functions A corresponding wavelength; as input variables, pixel index numbers in the original spectrum; Is a constant term representing the intercept offset of the wavelength axis; A linear scaling factor representing the wavelength axis, corresponding to the dispersion rate of the spectrometer, as a first order coefficient; is a high order term coefficient used to correct nonlinear response; S243, based on least square fitting calculation, solving 、 、 。
  4. 4. The method for calibrating an environmental parameter-adaptive Raman spectrum explosive identifier according to claim 3, wherein in S33, the method for correcting the second Raman spectrum is a resampling interpolation method, and specifically comprises: S331 defining new wavelength axes of equal spacing ; S332 inverse function based on the correction polynomial function Calculating a new wavelength axis Wavelength point on Corresponding original pixel coordinates ; S333, according to the original pixel coordinates by linear interpolation algorithm And its corresponding spectral intensity Calculating the wavelength point Spectral intensity at ; S334 for a new wavelength axis Each wavelength point of (3) Repeating S332-S333 to obtain a group of intensity values ; S335 is to And Is defined as the corrected second raman spectrum.
  5. 5. The method for calibrating an environment parameter adaptive Raman spectrum explosive identifier according to claim 4, wherein the environment sensor module comprises a temperature sensor and a humidity sensor, the real-time environment parameter in S35 comprises an environment temperature and an environment humidity, and the data reliability evaluation model is used for outputting a reliability score according to the environment temperature, the environment humidity and a signal-to-noise ratio of a second Raman spectrum.
  6. 6. The method for calibrating an environmental parameter-adaptive Raman spectrum explosive identifier according to claim 5, wherein in S36, the method for outputting the detection result and the corresponding reliability score comprises: data acquisition and input, namely inputting the ambient temperature, the ambient humidity and the signal to noise ratio; data preprocessing and feature vector components, wherein the processing unit calculates a reliability score based on the ambient temperature, the ambient humidity and the signal-to-noise ratio; and outputting a result, wherein the result comprises a detection result and a reliability score.
  7. 7. The method for calibrating an environmental parameter-adaptive Raman spectrum explosives identifier according to claim 6, wherein said key parameters in S24 comprise polynomial-fitting first-order coefficients And quadratic term coefficient ; Also comprises the following steps of S4: S41, the processing unit retrieves the history continuous from the calibration history database Calibrating the recorded key parameters to form a parameter time sequence; and S42, carrying out trend analysis on the parameter time sequence, and if the drift rate of any key parameter exceeds a preset threshold value, generating early warning information and prompting maintenance.
  8. 8. The method for calibrating an environmental parameter-adaptive Raman spectrum explosives identifier according to claim 7, wherein said S33 further comprises: and S336, preprocessing the second Raman spectrum, including algorithms based on wavelet transformation or principal component analysis, to reduce noise and enhance the characteristic peak signal-to-noise ratio.
  9. 9. The method for calibrating an environmental parameter-adaptive Raman spectrum explosive identifier according to claim 7, wherein in S34, the similarity calculation is performed by a cosine similarity algorithm or a least square method.
  10. 10. The method for calibrating an environmental parameter-adaptive Raman spectrum explosive identifier according to claim 7, wherein in step S2, the calibration phase is automatically triggered under any one or more of a condition that the identifier is turned on, a condition that a preset timing period is reached, and a condition that an environmental temperature change exceeds a predetermined range.

Description

Raman spectrum explosive identifier calibration method with self-adaptive environmental parameters Technical Field The invention belongs to the technical field of Raman spectrum, and particularly relates to a calibration method of an environment parameter self-adaptive Raman spectrum explosive identifier. Background The Raman spectrum identifier for identifying the explosive can generate data drift in long-time use and different environments, so that the spectrum data output by the Raman spectrum identifier deviate from the explosive spectrum reference data, and further the problems of false alarm and missing report can occur; one chinese patent with publication number CN104458701a discloses an automatic calibration method for a raman spectrum explosive identifier, which includes initializing the raman spectrum explosive identifier according to requirements, establishing an analysis curve according to different analysis stages, storing data, preparing the raman spectrum explosive identifier on site, and analyzing a sample by using the raman spectrum explosive identifier. The method improves the measurement accuracy and precision of the Raman spectrum explosive identifier, and reduces the influence of the measured explosive, especially the infrared explosive with rich infrared spectrum, on the spectrum signal of the Raman spectrum, so that the Raman spectrum explosive identifier can be automatically calibrated under various temperature conditions. In the prior art, the core principle is that in a controllable laboratory environment, various known explosive standards are measured by changing parameters such as temperature, data containing the corresponding relation of environment parameters and reference spectrums are established, when an application scene is on site, unknown samples are measured based on an identifier, and then pre-stored reference spectrums are called from a database according to the current environment parameters to carry out matching and calibration, but in actual security and security scenes, real explosive samples cannot be stored or used for field calibration in places such as airports and stations, and because of various types of explosives, new unknown types can possibly appear, all possible standards cannot be exhausted, in addition, the calibration needs to be completed quickly, and the process of measuring the standards on site can introduce unacceptable delay. Therefore, the invention provides a Raman spectrum explosive identifier calibrating method with self-adaptive environmental parameters. Disclosure of Invention In order to overcome the deficiencies of the prior art, at least one technical problem presented in the background art is solved. The technical scheme adopted for solving the technical problems is that the method for calibrating the Raman spectrum explosive identifier with self-adaptive environmental parameters comprises the following steps: S1, constructing a Raman spectrum detection system, wherein the Raman spectrum detection system comprises a laser source, a beam splitter, a detector, a built-in standard substance module, a storage unit, a processing unit and an environment sensor module, wherein the storage unit is used for storing a standard Raman spectrum database and a calibration history database; s2, performing calibration, including: S21, controlling the laser source to irradiate a built-in standard module, wherein a calibration material which is known and has a stable characteristic Raman peak position is loaded in the built-in standard module; s22, collecting a first Raman spectrum generated by the calibration material through the detector and the beam splitter; S23, identifying actual measurement pixel coordinates of the calibration material in the first Raman spectrum; S24, comparing the actually measured pixel coordinates with standard Raman displacement in a standard Raman spectrum database, calculating a wavelength-pixel coordinate correction relation established under the current instrument working condition, and storing key parameters of the calibration into the calibration history database; s3, detecting the sample to be detected, including: s31, controlling the laser source to irradiate a sample to be detected; s32, collecting a second Raman spectrum generated by the sample to be detected; S33, correcting the pixel index of the second Raman spectrum by utilizing the wavelength-pixel coordinate correction relation established in the S24, generating spectrum data of wavelengths, and obtaining a corrected second Raman spectrum; s34, performing similarity calculation on the corrected second Raman spectrum and a reference spectrum in a standard Raman spectrum database to obtain similarity; S35, calculating the reliability score of the detection result based on the similarity and the real-time environmental parameters from the environmental sensor module and the data reliability evaluation model; S36, outputting the detection result and the correspon