Multi-component gas dynamic imaging monitoring system and method suitable for laser forcible entry rescue

Abstract

The invention discloses a multi-component gas dynamic imaging monitoring system and method suitable for laser forcible entry rescue. The system comprises a laser emitting unit, a signal collecting unit, a signal processing unit and an imaging unit. The laser emitting unit is used for generating and emitting a laser signal with a specific wavelength and detecting multi-component gas in a target environment; the signal acquisition unit is used for receiving a laser signal returned after passing through a target environment and converting the laser signal into an electric signal; the signal processing unit is used for analyzing and processing the electric signal received from the signal acquisition unit and extracting an effective signal containing the concentration and type information of the laser hazardous gas; the imaging unit is used for combining the processed signal data, converting the processed signal data into visual images or graphs and outputting the visual images or graphs to generate a real-time multi-component gas distribution diagram; real-time imaging can be realized in a complex environment, gas distribution is visually displayed by adopting a pseudo-color image, and the method has anti-interference and high sensitivity and is suitable for rescue decision assistance.

Description

Technical Field

[0001] The present invention relates to the technical field of gas dynamic imaging monitoring, and particularly to a multi-component gas dynamic imaging monitoring system and method applicable to laser demolition rescue. Background Art

[0002] When accidents occur in mines, buildings, chemical industrial areas, and vehicles loaded with flammable and explosive gases, extremely common flammable, explosive, and toxic hazardous chemical gases such as methane (CH4), ammonia (NH3), and ethane (C2H4) may exist at the disaster accident site. Personnel may be trapped under the collapsed body, and the accident site situation is extremely complex. If rescue operations are carried out blindly, secondary disasters are likely to occur, causing harm to the trapped and rescue personnel.

[0003] Considering that most of the laser demolition rescue sites are in dangerous environments and areas, rescue personnel cannot approach directly, and at the same time, to ensure the safety of rescue personnel, developing a multi-component gas intelligent dynamic monitoring system with high sensitivity, strong anti-noise ability, and capable of real-time monitoring of the concentration of flammable and explosive gases at the rescue site has become one of the main directions of safety detection.

[0004] Currently, the commonly used methods for monitoring dangerous gases in the demolition area are mainly divided into non-optical methods and optical methods according to the detection principle.

[0005] Optical methods mainly include electrochemistry method, catalytic combustion method, semiconductor gas sensor method, thermal conductivity analysis method, ionization method, paramagnetic method, passive detector tube method, gas chromatography method, mass spectrometry analysis method, gas chromatography-mass spectrometry coupling method, ultrasonic analysis method, etc. Non-optical methods need to collect samples of the target gas to achieve gas detection, which has the problems of long response time, poor timeliness, high maintenance cost, and being easily restricted by temperature, humidity, pressure, and the on-site environment. The disaster rescue scene is complex and changeable, there are dangerous gases, and secondary disasters are likely to cause harm to personnel. Non-traditional optical methods are difficult to meet the non-contact, safe, and efficient practical requirements of complex disaster scenes.

[0006] Optical methods mainly include Fourier transform infrared spectroscopy, optical interferometry, ultraviolet-visible absorption spectroscopy, non-dispersive infrared analysis, lidar, differential absorption spectroscopy, laser-induced fluorescence, chemiluminescence, Raman laser spectroscopy, photoacoustic spectroscopy, tunable diode laser absorption spectroscopy, etc. In terms of high selectivity and high sensitivity, although Fourier transform infrared spectroscopy and non-dispersive infrared analysis have certain advantages, they are vulnerable to interference from other gases in complex rescue environments and have relatively low sensitivity; in terms of rapid response, although lidar and optical interferometry can achieve real-time monitoring, their equipment is complex and requires high environmental conditions, and the response speed is not as fast as that of tunable diode laser absorption spectroscopy; in terms of non-contact measurement, although Raman spectroscopy and photoacoustic spectroscopy can also achieve non-contact measurement, their sensitivity is low, and the long-distance detection effect is better with tunable diode laser absorption spectroscopy; in terms of multi-gas detection, chemiluminescence and laser-induced fluorescence are usually only applicable to specific gases, and the application range is limited.

[0007] The defects of the prior art are as follows:

[0008] 1. The data generated by a single instrument is relatively single, lacking comprehensive analysis ability. It is difficult to comprehensively understand the complex situation in the environment of the monitored laser demolition area through a single data source. Moreover, the measuring lasers of each detector are independently emitted, and there is a physical distance between them, resulting in the final measurement result not truly reflecting the integrated concentration of the same path and generating measurement errors.

[0009] 2. Signal processing and noise suppression of a single laser telemetry instrument are usually relatively basic. Especially in complex environments, it is easily interfered by background noise, affecting the measurement accuracy.

[0010] 3. The spectral selectivity of a single laser telemetry instrument is usually relatively narrow, and the resolution is relatively low. It is difficult to distinguish gases with similar absorption spectra, resulting in inaccurate or misjudged detection results.

[0011] 4. A single laser telemetry instrument is usually designed for specific tasks and has poor scalability. For example, if it is necessary to increase the types of monitored gases or the monitoring range, new equipment needs to be purchased or existing equipment needs to be greatly modified, which greatly increases the cost.

[0012] 5. The laser demolition rescue scenario is complex and changeable. A single laser telemetry instrument may need to be frequently calibrated under different environmental conditions such as temperature and humidity, increasing the complexity of operation and maintenance, and it is unable to effectively distinguish the presence or absence of low-concentration gases. Summary of the Invention

[0013] In order to overcome the above technical problems, the object of the present invention is to provide a multi-component gas dynamic imaging monitoring system and method applicable to laser demolition rescue. The system and method have high-precision and multi-component gas monitoring capabilities, can perform real-time imaging in complex environments, intuitively display gas distribution using pseudo-color images, and have anti-interference and high sensitivity, and are applicable to rescue decision-making assistance.

[0014] The technical solution adopted by the present invention is:

[0015] A multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue, the system includes a laser emission unit 1, a signal acquisition unit 2, a signal processing unit 3 and an imaging unit 4;

[0016] The laser emission unit 1 is used to generate and emit laser signals of a specific wavelength to detect multi-component gases in the target environment;

[0017] The signal acquisition unit 2 is used to receive the laser signal returned after passing through the target environment and convert it into an electrical signal;

[0018] The signal processing unit 3 is used to analyze and process the electrical signal received from the signal acquisition unit, and extract an effective signal containing information on the concentration and type of laser hazardous gases;

[0019] The imaging unit 4 is used to combine the processed signal data and convert it into a visual image or graphic output to generate a real-time multi-component gas distribution map;

[0020] The four units cooperate to complete the entire system's work process through physical connection and signal transmission.

[0021] The laser emission unit 1 outputs laser in the wavelength range required for detecting target gases in the demolition area through time-division multiplexing method, and emits it to the detection area in a time-sharing manner. When this laser passes through the detection area, gas molecules selectively absorb light matching their characteristic wavelengths;

[0022] The time-division multiplexing method is a signal transmission method. By dividing different signals into multiple time periods on the time axis, each signal can pass through the same transmission channel in sequence. This method divides the working time of the laser emission unit into different time periods, and each time period is assigned to a laser of a specific wavelength or a specific direction, thereby improving laser utilization rate, reducing interference and signal aliasing, and realizing the detection of multi-component gases;

[0023] The laser emission unit 1 outputs laser in the wavelength range required for detecting target gases in the demolition area;

[0024] The laser emission unit 1 includes a laser emitter 7, a laser controller 5 and a laser driver 6;

[0025] The signal acquisition unit 2 includes an analog-to-digital converter 14, a lock-in amplifier 15, an image recording and analyzing instrument 16, and a display screen 17;

[0026] The laser controller 5 and the laser driver 6 are connected in a two-wire manner through a BNC cable 18 and a multimode optical fiber 19. The laser driver is adjacent to the laser emitter 7 to drive it to generate a laser signal. The laser signal is collimated by a laser collimator 11 to ensure that the beam directions are consistent. The collimated laser beam is further focused by a Fresnel lens 12 and projected onto the target area. The cooperative controller 10 and the photodetector 13 are connected through a shielded cable 20. The reflected or scattered echo signal is received by the photodetector 13 arranged at the end of the optical path, which converts the optical signal into an electrical signal. The photodetector 13 and the analog-to-digital converter 14 are connected through a BNC cable. The electrical signal is transmitted to the analog-to-digital converter 14 and converted into a digital signal. Then, the analog-to-digital converter 14 and the lock-in amplifier 15 are connected through a shielded cable 20. The processed signal is analyzed and processed by the lock-in amplifier 15, and finally, dynamic imaging analysis is performed by the image recording and analyzing instrument 16. The lock-in amplifier 15 and the image recording and analyzing instrument 16 are connected through a BNC cable 18. The processed signal is displayed in real time on the display screen 17. The image recording and analyzing instrument 16 and the display screen 17 are connected through an HDMI cable 21.

[0027] The laser driver 6 includes a soft-start circuit 6-1. The soft-start circuit 6-1 is located at the front end of the laser driver and is directly connected to a constant-current circuit 6-2 through a cable. The constant-current circuit 6-2 is connected after the soft-start circuit 6-1 and is connected to a modulation signal circuit 6-3 and a laser cell 6-5 through a cable. The modulation signal circuit 6-3 is simultaneously connected to a feedback circuit 6-6. The protection circuit 6-4 is in parallel with the laser cell 6-5 and other control circuits. The laser cell 6-5 is connected to the feedback circuit 6-6. The feedback circuit 6-6 is located at the output end of the laser cell, monitors the state of the laser output, and feeds back the information to the constant-current circuit and the modulation signal circuit.

[0028] The laser emitter 7 is installed in the laser cell 6-5 of the laser driver 6. The current is gradually increased through the soft-start circuit 6-1 to protect the laser emitter 7. A stable operating current is maintained by the constant-current circuit 6-4, and the laser output is adjusted through the modulation signal circuit 6-3. The feedback circuit 6-6 monitors the laser power in real time to ensure stable output. The protection circuit 6-4 cuts off the power supply or reduces the current in case of an abnormality to prevent damage.

[0029] The laser controller 5 includes a single-chip microcomputer 5-1, which is located at the front end of the laser controller and is connected to a digital potentiometer 5-2 and a signal adjuster 5-7 through data lines; the digital potentiometer 5-2 is connected between the single-chip microcomputer 5-1 and the power amplification module 5-3; the power amplification module 5-3 is located at the output end of the control system and is connected to the digital potentiometer 5-2; the thermoelectric cooler 5-4 is connected to the power amplification module 5-3 and the temperature sensor 5-5; the temperature sensor 5-5 feeds back temperature information to the analog-to-digital conversion module 5-6 through a data line; the analog-to-digital conversion module 5-6 is connected to the signal adjuster 5-7; the signal adjuster 5-7 is located at the output end of the power amplification module and is connected to the single-chip microcomputer 5-1 and an external laser emitter.

[0030] The phase-locked amplifier 15 includes a signal generator 15-1, which is located at the input end of the phase-locked amplifier and is connected to a band-pass filter 15-2 through a signal line; the band-pass filter 15-2 receives the signal transmitted by the signal generator 15-1; the multiplier 15-3 receives the input signal from the band-pass filter 15-2 and at the same time receives the reference signal from the reference signal generator 15-8 for phase comparison, and the two input signals are connected to the multiplier through signal lines; the low-pass filter 15-4 is connected to the multiplier 15-3 through a signal line; the output amplifier 15-5 is connected to the low-pass filter 15-4 through a control signal line and is responsible for outputting the processed signal; the phase-locked loop 15-6 is connected to the reference signal generator 15-8 and the reference trigger 15-7 to lock the phase relationship between the reference signal and the input signal; the reference trigger 15-7 is connected to the phase-locked loop 15-6 and the reference signal generator 15-8.

[0031] Among them, the band-pass filter 15-2 of the phase-locked amplifier 15 filters out non-target signals, and then receives the input signal generated by the signal generator 15-1 and the reference signal generated by the reference signal generator 15-8. The output signal activates the reference trigger 15-7, and the two are phase-synchronized. The multiplier 15-3 multiplies them to generate an output signal containing low-frequency useful signals and high-frequency noise; the low-pass filter 15-4 filters out high-frequency noise and retains useful low-frequency signals to extract weak target signals. The entire signal processing process depends on the phase calibration of the reference signal by the phase-locked loop 15-6. The low-pass filter separates the precise signal, and the output amplifier 15-5 amplifies the processed target signal to achieve noise suppression and signal enhancement;

[0032] The image recording analyzer 17 demodulates the digital signals of different wavelengths, extracts the frequency components related to the absorption peaks of the target gas, uses a known gas absorption spectral line library to match the detected spectral signals with the absorption spectra of the reference gas, and determines the concentration and composition of the specific gas through a fitting algorithm (such as the least squares method). Different colors and brightness are assigned according to the different concentrations of the gas to generate a pseudo-color image.

[0033] Further, the image recording analyzer 17 receives the digital signals transmitted by the signal processing unit 3. This signal contains the information after the interaction between the laser of different wavelengths and the target gas when passing through the monitoring area. For each wavelength, the change in signal intensity corresponds to the concentration characteristics of the gas.

[0034] Preprocess the input signal. First, perform a filtering operation to remove background noise and non-target frequency interference. A band-pass filter is used to select the frequency components related to the absorption peaks of the target gas. The filtering equation is:

[0035] s f (t) = s(t) * h(t)

[0036] where s f (t) is the output signal, s(t) is the input signal, h(t) is the impulse response of the band-pass filter, and * represents the convolution operation.

[0037] In the frequency domain, it can be expressed as:

[0038] S f (f) = S(f) · H(f)

[0039] where S(f) is the Fourier transform of the input signal and H(f) is the frequency response of the filter.

[0040] Demodulate the filtered signal. The demodulation method uses a lock-in amplifier, that is, the phase of the reference signal is synchronized with the input signal. The demodulated signal can be expressed as:

[0041] V d (t) = V f (t) · cos(ωt + φ)

[0042] where V f (t) is the filtered signal, ω is the angular frequency of the reference signal, and φ is the phase difference.

[0043] After low-pass filtering, the DC component is obtained:

[0044]

[0045] where A is the signal amplitude, and cos(φ) reflects the phase relationship between the input signal and the reference signal.

[0046] After demodulation, the frequency components related to the absorption peak of the target gas are extracted. Setting the intensity of the laser signal after absorption as I, its relationship can be described by the Lambert-Beer law:

[0047] I = I0exp(-αCL)

[0048] where I0 is the initial laser intensity, α is the absorption coefficient, C is the gas concentration, and L is the optical path length;

[0049] To find the gas concentration C, take the logarithm of the above formula and solve to obtain that the gas concentration can be expressed as:

[0050]

[0051] Collect the demodulated signals at different wavelengths λ to obtain the corresponding harmonic signal amplitudes. The amplitudes are related to the absorption coefficient α and the gas concentration C;

[0052] Since α is known from the standard absorption line library of the gas and is related to the absorption line S(λ) in the standard absorption line library:

[0053] α = σ(λ) = S(λ)

[0054] where σ(λ) is the absorption cross-section of the gas;

[0055] The demodulated spectral signal:

[0056] M(λ) = K exp(-S(λ)CL)

[0057] where K is a constant related to the system gain;

[0058] Match the demodulated spectral signal M(λ) with the known gas absorption line library S(λ). During the matching process, the least squares method is used for fitting analysis. The least squares objective function is:

[0059] min k ∑ λ [M(λ) - kS(λ)] 2

[0060] where k is the parameter to be fitted, representing the proportionality factor of the gas concentration. To find the optimal k, take the derivative of the objective function with respect to k and set it equal to zero:

[0061]

[0062] Solve to obtain k:

[0063]

[0064] During the fitting process, the weighted least squares method can be further used to increase the robustness of the fitting. The objective function of the weighted least squares method is:

[0065] min k ∑ λ ω(λ)[M(λ)-kS(λ)] 2

[0066] where ω(λ) is the weight factor;

[0067] Similarly, the objective function is differentiated with respect to k and set to zero to solve for k:

[0068]

[0069] In gas imaging, according to the gas concentration information obtained by fitting, the concentration value of each gas is mapped to different colors and brightness levels to generate a pseudo-color image;

[0070] Set the gas concentration range to [C min , C max , and use the method of linear mapping to map the concentration value to the brightness value B in the color space;

[0071]

[0072] The concentrations of different gases are given different colors, thus forming an intuitive pseudo-color distribution map in the image. Set the color value in the RGB color space to (R, G, B) = f(C);

[0073] where f(C) is the color mapping function, which is used to calculate the corresponding RGB color value according to the gas concentration C.

[0074] Furthermore, the specific mapping method adopts linear or non-linear interpolation methods; for a certain gas, the following linear mapping is used:

[0075] When C = C min , (R, G, B) = (0, 0, 255) (blue)

[0076] When C = C max , (R, G, B) = (255, 0, 0) (blue)

[0077] The intermediate value is linearly interpolated according to the concentration ratio:

[0078]

[0079] G = 0

[0080] B = 255 - R

[0081] The finally generated pseudo-color image is presented in real time through the display screen 17. The system updates the image of the inverted multi-component gas concentration and distribution in real time, and automatically or manually marks the areas where the gas concentration exceeds the standard, helping the rescue team quickly identify potential hazard areas.

[0082] A method for using a multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue includes the following steps:

[0083] Step 1, start the multi-component gas dynamic imaging monitoring system for pre-calibration. Start the laser controller 5 and the laser driver 6 to ensure that the laser emitter 7 emits a stable laser signal after startup. Adjust the laser collimator 11 to collimate the laser beam and make the beam directions consistent to ensure the accuracy of the subsequent laser transmission path. Start the laser controller 5. Among them, the temperature sensor 5-5 and the thermoelectric cooler 5-4 adjust the temperature of the laser emitter 7 in real time to avoid laser wavelength drift caused by temperature fluctuations, thereby optimizing the laser transmission path and ensuring measurement accuracy.

[0084] Step 2, according to the actual situation of the laser demolition rescue environment, adjust the positions of the laser collimator 11 and the Fresnel lens 12 to ensure that the laser beam can cover all areas to be monitored. Combine the on-site feedback information to adjust the optical path in real time to avoid laser deviation caused by collapsed structures or other obstacles, and ensure the accuracy and comprehensiveness of the monitoring.

[0085] Step 3, according to the actual situation of the laser demolition rescue environment, use the laser emission unit 1 to emit laser beams of multiple wavelengths at different time periods through time-division multiplexing. Collaborate with the controller 10 and the photodetector 13 to ensure that the laser can quickly switch between different wavelengths, and the photodetector 13 can respond immediately after the laser is emitted to accurately collect the reflection signals of each wavelength, avoiding cross-interference of different gas signals, and realizing efficient and accurate multi-component gas detection.

[0086] Step 4, configure the types and quantities of gases to be detected in the system interface, input the known gas absorption spectral line data, and the analog-to-digital converter 14 and the lock-in amplifier 15 work together to adjust the gain of the photodetector 13. If the signal intensity is too low, gradually increase the gain; if the signal intensity is too high, reduce the gain to reduce noise, and ensure that the signal processing module of the system can accurately distinguish the absorption signals of different gases.

[0087] Step 5: Activate the real-time monitoring mode. Through the image recording analyzer 16 and the display screen 17, view the gas concentration change graph in real time, monitor the dynamic diffusion of hazardous gases. According to the gas concentration distribution map generated by the system and the trend analysis results, on-site rescue personnel can timely adjust the rescue strategy, optimize the rescue path and plan to ensure safety and efficiency during the rescue process. When the gas concentration in a certain area is detected to exceed the standard, the display screen 17 will automatically mark the dangerous area to help the rescue team quickly identify potential hazards and thus take corresponding countermeasures.

[0088] Advantages of the present invention:

[0089] The present invention improves the traditional contact detection method of gas detection technology in the past, solves the problem that the dangerous area of demolition is prone to safety accidents. Through the laser emission unit and the signal acquisition unit, real-time collection and transmission of multi-component hazardous gases in the laser demolition area to the signal processing unit and the imaging unit are realized. According to the monitoring and analysis of the concentration and change rate of hazardous gases at the laser demolition rescue site, it has very important practical value and practical significance for preventing secondary accidents at the laser demolition site rescue, determining the environmental hazard of the demolition area, and making scientific disaster relief decisions;

[0090] The present invention has strong anti-interference ability, can filter out background light, noise signals and other interference sources, and ensure accurate detection results can still be obtained in complex environments, realizing long-distance contact multi-component hazardous gas monitoring;

[0091] Both the laser emission unit and the signal acquisition unit of the present invention adopt the time-division multiplexing method, which ensures accurate gas monitoring in the predetermined time window period and avoids crosstalk that may occur when receiving multiple wavelength signals simultaneously. Description of the drawings

[0092] Figure 1 It is a schematic diagram of the architecture of the present invention.

[0093] Figure 2 It is a schematic diagram of the structure of the present invention.

[0094] Figure 3 It is a structural diagram of the laser driver of the present invention.

[0095] Figure 4 It is a structural diagram of the laser controller of the present invention.

[0096] Figure 5 It is a structural diagram of the lock-in amplifier of the present invention.

[0097] Reference numerals:

[0098] 1-Laser emission unit, 2-Signal acquisition unit, 3-Signal processing unit, 4-Imaging unit, 5-Laser controller, 5-1 Single chip microcomputer, 5-2 Digital potentiometer, 5-3 Power amplifier module, 5-4 Thermoelectric cooler, 5-5 Temperature sensor, 5-6 Analog-to-digital conversion module, 5-7 Signal regulator, 6-Laser driver, 6-1 Slow start circuit, 6-2 Constant current circuit, 6-3 Modulation signal circuit, 6-4 Protection circuit, 6-5 Laser slot, 6-6 Feedback circuit, 7-Laser emitter, 8-Multi-channel laser generator Device, 9-fiber coupler, 10-cooperative controller, 11-laser collimator, 12-Fresnel lens, 13-photodetector, 14-analog-to-digital converter, 15-locked amplifier, 15-1 signal generator, 15-2 bandpass filter, 15-3 multiplier, 15-4 low-pass filter, 15-5 output amplifier, 15-6 reference signal generator, 15-7 reference trigger, 15-8 reference signal generator, 16-image recording analyzer, 17-display screen, 18-BNC cable, 19-multimode optical fiber. DETAILED DESCRIPTION

[0099] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0100] The present invention provides a multi-component gas dynamic imaging monitoring system suitable for laser rescue. The schematic diagram of the system architecture is as follows: Figure 1 As shown, the system includes a laser emitting unit 1, a signal acquisition unit 2, a signal processing unit 3 and an imaging unit 4.

[0101] Among them, the laser emitting unit 1 provided in this embodiment outputs the laser in the band range required for detecting the target gas in the demolition area through the time division multiplexing method, and emits it to the detection area in time division. When the laser passes through the detection area, the gas molecules selectively absorb the light matching its characteristic wavelength.

[0102] Specifically, the laser emitting unit 1 provided in this embodiment outputs a laser in the wavelength range required for detecting the target gas in the demolition area. For example, when the laser demolition area is a coal mine shaft, since the multi-component gases in the coal mine shaft scene are mainly carbon monoxide (CO), methane (CH4) and hydrogen sulfide (H2S), etc., the three gases correspond to different peaks of the best absorption spectra of 4.6μm, 3.3μm and 2.6μm, etc., then the laser emitting unit 1 provided in this embodiment emits three laser wavelengths in time-division multiplexing method.

[0103] The laser emission unit 1 emits laser light through an optical fiber and a collimator. The signal acquisition unit 2 focuses the returned signal through a lens. The signal processing unit 3 amplifies and demodulates the received electrical signal. Finally, the imaging unit presents the information in the form of an image. The physical connections between the units ensure the complete transmission and real-time nature of the signals, thus enabling the precise monitoring and imaging of multi-component gases.

[0104] Specifically, the laser emitter 7 provided in this embodiment is installed in the laser slot 6-5 of the laser driver 6. The current is gradually increased through the soft-start circuit 6-1 to protect the laser emitter. The constant-current circuit 6-4 maintains a stable operating current, and the laser output is adjusted through the modulation signal circuit 6-3. The feedback circuit 6-6 monitors the laser power in real time to ensure stable output. The protection circuit 6-4 cuts off the power supply or reduces the current in case of an abnormality to prevent damage.

[0105] Specifically, the laser controller 5 provided in this embodiment monitors the temperature of the laser in real time through the temperature sensor 5-5 and converts it into a digital signal for transmission to the single-chip microcomputer 5-1. The single-chip microcomputer 5-1 compares the current temperature with the preset target temperature. After calculating the error, it adjusts the digital potentiometer 5-2 through the signal regulator 5-7 to control the power amplifier module 5-3 to drive the thermoelectric cooler 5-4 for temperature adjustment. The thermoelectric cooler 5-4 adjusts the temperature of the laser to the set value through heating or cooling. The temperature sensor 5-5 continuously feeds back the temperature information to form a closed-loop control to ensure the stability of the laser temperature and prevent wavelength drift.

[0106] In this embodiment, the gas detection scenarios for laser demolition mainly include deep well rescue, industrial park collapse rescue, and traffic accident rescue, etc. When the laser beam passes through the laser demolition area of the gas to be measured, the gas in the area to be detected selectively absorbs the light matching its characteristic wavelength. When the wavelength of the laser matches the absorption wavelength of the gas molecules, the gas molecules will absorb a part of the laser energy, resulting in a decrease in the laser intensity passing through the sample. The gas concentration information is obtained by measuring the laser intensity.

[0107] The signal acquisition unit 2 provided in this embodiment mainly consists of an analog-to-digital converter 14 and a lock-in amplifier 15 in the art.

[0108] Among them, the analog-to-digital converter 14 has multiple input channels. Each channel can be connected to an independent analog signal source, and the multiple input channels share the same converter. The analog-to-digital converter uses the time-division multiplexing method to switch multiple signals at high frequency to achieve real-time and synchronous multi-component gas sampling conversion.

[0109] Among them, the band-pass filtering 15-2 of the lock-in amplifier 15 filters out non-target signals. Then, by receiving the input signal generated by the signal generator 15-1 and the reference signal generated by the reference signal generator 15-8, the output signal is input to the activation reference trigger 15-7, and the two are phase-synchronized. The multiplier 15-3 multiplies them to generate an output signal containing low-frequency useful signals and high-frequency noise. The low-pass filter 15-4 filters out the high-frequency noise and retains the useful low-frequency signals to extract weak target signals. The entire signal processing process relies on the phase calibration of the reference signal by the phase-locked loop 15-6. The low-pass filter separates the precise signals, and the output amplifier 15-5 amplifies the processed target signals to achieve noise suppression and signal enhancement;

[0110] The signal acquisition unit 2 provided in this embodiment mainly consists of an image recording and analyzer 16 and a display screen 17 in the art;

[0111] Among them, the image recording and analyzer 17 demodulates the input digital signals of different wavelengths, extracts the frequency components related to the absorption peaks of the target gas, uses a known gas absorption spectral line library to match the detected spectral signals with the absorption spectra of the reference gas, and determines the concentration and composition of specific gases through a fitting algorithm (such as the least squares method). Different colors and brightness are assigned according to the different concentrations of the gas to generate a pseudo-color image. The system updates the image of the retrieved multi-component gas concentration and distribution in real time, and automatically or manually marks the areas where the gas concentration exceeds the standard to help the rescue team quickly identify potential hazard areas.

[0112] As Figure 2 shown, the laser controller 5 and the laser driver 6 are connected in a double-wire manner through a BNC cable 18 and a multimode optical fiber 19. The laser driver is adjacent to the laser emitter 7 to drive it to generate a laser signal. The laser signal is collimated by the laser collimator 11 to ensure that the beam directions are consistent. The collimated laser beam is further focused by the Fresnel lens 12 and projected onto the target area. The cooperative controller 10 and the photodetector 13 are connected through a shielded cable 20. The reflected or scattered echo signal is received by the photodetector 13 arranged at the end of the optical path, and the optical signal is converted into an electrical signal. The photodetector 13 and the analog-to-digital converter 14 are connected through a BNC cable, and the electrical signal is transmitted to the analog-to-digital converter 14 and converted into a digital signal. The analog-to-digital converter 14 and the lock-in amplifier 15 are connected through a shielded cable 20. The processed signal is analyzed and processed by the lock-in amplifier 15, and finally, the image recording and analyzer 16 performs dynamic imaging analysis. The lock-in amplifier 15 and the image recording and analyzer 16 are connected through a BNC cable 18, and the processed signal is displayed in real time on the display screen 17. The image recording and analyzer 16 and the display screen 17 are connected through an HDMI cable 21;

[0113] As Figure 3As shown, the soft start circuit 6-1 is located at the front end of the laser driver and is directly connected to the constant current circuit 6-2 through a cable; the constant current circuit 6-2 is connected after the soft start circuit 6-1 and is connected to the modulation signal circuit 6-3 and the laser cell 6-5 through a cable; the modulation signal circuit 6-3 is simultaneously connected to the feedback circuit 6-6; the protection circuit 6-4 is in parallel with the laser cell 6-5 and other control circuits; the laser cell 6-5 is connected to the feedback circuit 6-6; the feedback circuit 6-6 is located at the output end of the laser cell, monitors the state of the laser output, and feeds back information to the constant current circuit and the modulation signal circuit;

[0114] As Figure 4 shown, the single-chip microcomputer 5-1 is located at the front end of the laser controller and is connected to the digital potentiometer 5-2 and the signal adjuster 5-7 through data lines; the digital potentiometer 5-2 is connected between the single-chip microcomputer 5-1 and the power amplification module 5-3; the power amplification module 5-3 is located at the output end of the control system and is connected to the digital potentiometer 5-2; the thermoelectric cooler 5-4 is connected to the power amplification module 5-3 and the temperature sensor 5-5; the temperature sensor 5-5 feeds back the temperature information to the analog-to-digital conversion module 5-6 through a data line; the analog-to-digital conversion module 5-6 is connected to the signal adjuster 5-7; the signal adjuster 5-7 is located at the output end of the power amplification module and is connected to the single-chip microcomputer 5-1 and an external laser emitter;

[0115] The laser controller 5 monitors the temperature of the laser in real time through the temperature sensor 5-5 and converts it into a digital signal and transmits it to the single-chip microcomputer 5-1; the single-chip microcomputer 5-1 compares the current temperature with the preset target temperature, calculates the error, and then adjusts the digital potentiometer 5-2 through the signal adjuster 5-7 to control the power amplification module 5-3 to drive the thermoelectric cooler 5-4 for temperature adjustment; the thermoelectric cooler 5-4 adjusts the temperature of the laser to the set value through heating or cooling, and the temperature sensor 5-5 continuously feeds back the temperature information to form a closed-loop control to ensure the stability of the laser temperature and prevent wavelength drift.

[0116] As Figure 5As shown, the signal generator 15-1 is located at the input end of the phase-locked amplifier and is connected to the bandpass filter 15-2 through a signal line; the bandpass filter 15-2 receives the signal transmitted by the signal generator 15-1; the multiplier 15-3 receives the input signal from the bandpass filter 15-2 and the reference signal from the reference signal generator 15-8 at the same time, performs phase comparison, and the two input signals are connected to the multiplier through a signal line; the low-pass filter 15-4 is connected to the multiplier 15-3 through a signal line; the output amplifier 15-5 is connected to the low-pass filter 15-4 through a control signal line, and is responsible for outputting the processed signal; the phase-locked loop 15-6 is connected to the reference signal generator 15-8 and the reference trigger 15-7, and locks the phase relationship between the reference signal and the input signal; the reference trigger 15-7 is connected to the phase-locked loop 15-6 and the reference signal generator 15-8;

[0117] The working principle of a multi-component gas dynamic imaging monitoring system suitable for laser demolition and rescue provided by the present invention is as follows:

[0118] When multi-component hazardous gas detection is carried out in the laser demolition area, the laser emitting unit 1 combines the time division multiplexing method to time-divisionally emit the detection multi-wavelength laser beam to the monitoring area, wherein, according to the Lambert-Beer law, the absorption of light by the gas can be expressed by the following formula:

[0119] I=I0exp(-αCL)

[0120] Where I0 is the initial laser intensity, α is the absorption coefficient, C is the gas concentration, and L is the optical path length;

[0121] When there are multiple gas components, the absorption of light is the superposition of the absorption of each component, which can be expressed as:

[0122] I=I0exp(-∑ i α i CL)

[0123] Among them, α i is the absorption coefficient of the ith gas, and C is the concentration of the ith gas;

[0124] Therefore, in the laser demolition area, the different gas molecules to be detected will interact with the laser of a specific wavelength and absorb the light of the corresponding wavelength. Using the above formula and method, the concentration of each dangerous gas can be monitored and calculated in real time, thereby realizing the detection of multi-component dangerous gases;

[0125] The Fresnel lens focuses the reflected laser beam onto the photodetector, further improving the detection accuracy and sensitivity;

[0126] The photodetector, in combination with the cooperative controller, receives laser beams of different wavelengths reflected by detection in a time-division manner, and converts the laser beam carrying the gas characteristic absorption band into an electrical signal; the analog-to-digital converter converts electrical signals carrying different gases into digital signals by using a time-division multiplexing method to switch multiple signals at a high frequency; the lock-in amplifier amplifies, filters, and fits the input different digital signals to determine the gas type and concentration information in the laser demolition area; the imaging recording analyzer assigns different colors and brightness according to the gas type and concentration information, and the display screen updates the image of the retrieved multi-component gas concentration and distribution in real time, and automatically or manually marks the areas where the gas concentration exceeds the standard;

[0127] The core technology of the present invention adopts a time-division multiplexing method. By emitting multiple lasers of specific wavelengths in a time-division manner, interacting with the characteristic absorption spectra of different gas molecules, combining signal processing algorithms and imaging technologies, it realizes the real-time display of the distribution and changes of multi-component gases of dangerous gases, and real-time monitors the gas diffusion in a dangerous environment, providing an auxiliary decision-making basis for laser demolition rescue;

[0128] In practical applications, a corresponding specific usage method is given based on a multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue, including the following steps:

[0129] Step 1: Start the multi-component gas dynamic imaging monitoring system, perform pre-calibration, start the laser controller 5 and the laser driver 6 to ensure that the laser emitter 7 emits a stable laser signal after startup, and adjust the laser collimator 11 to collimate the laser beam to make the beam direction consistent, ensuring the accuracy of the subsequent laser transmission path. Start the laser controller 5. Among them, the temperature sensor 5-5 and the thermoelectric cooler 5-4 adjust the temperature of the laser emitter 7 in real time to avoid laser wavelength drift caused by temperature fluctuations, thereby optimizing the laser transmission path and ensuring measurement accuracy;

[0130] Step 2: According to the actual situation of the laser demolition rescue environment, adjust the positions of the laser collimator 11 and the Fresnel lens 12 to ensure that the laser beam can cover all areas that need to be monitored. Combine the on-site feedback information and adjust the optical path in real time to avoid laser deviation caused by collapsed structures or other obstacles, ensuring the accuracy and comprehensiveness of the monitoring;

[0131] Step 3: According to the actual situation of the laser demolition rescue environment, use the laser emission unit 1 to emit laser beams of multiple wavelengths in a time-division manner through a time-division multiplexing method. The cooperative controller 10 and the photodetector 13 cooperate to ensure that the laser quickly switches between different wavelengths, and the photodetector 13 can immediately respond after the laser is emitted, accurately collecting the reflection signals of each wavelength, avoiding cross-interference of different gas signals, and realizing efficient and accurate multi-component gas detection;

[0132] Step 4, configure the types and quantities of gases to be detected in the system interface, input the known gas absorption spectral line data, and the analog-to-digital converter 14 and the lock-in amplifier 15 work together to adjust the gain of the photodetector 13. If the signal intensity is too low, gradually increase the gain; if the signal intensity is too high, reduce the gain to reduce noise, ensuring that the signal processing module of the system can accurately distinguish the absorption signals of different gases;

[0133] Step 5, start the real-time monitoring mode, and view the gas concentration change graph in real time through the image recording analyzer 16 and the display screen 17 to monitor the dynamic diffusion of dangerous gases. According to the gas concentration distribution map and trend analysis results generated by the system, on-site rescue personnel can timely adjust the rescue strategy, optimize the rescue path and plan, and ensure the safety and efficiency during the rescue process. When the gas concentration in a certain area is detected to exceed the standard, the display screen 17 will automatically mark the dangerous area to help the rescue team quickly identify potential hidden dangers, so as to take corresponding countermeasures.

[0134] 1. Multi-wavelength laser emission technology: The laser emission unit can emit lasers of multiple specific wavelengths to match the best absorption spectral lines of the target gas. This technology uses the time-division multiplexing method to emit lasers time-divisionally, ensuring that each laser emitter emits within different time windows to avoid signal interference.

[0135] 2. Dynamic imaging technology: The imaging unit converts the processed signal into a visual image to display the distribution of multi-component gases in real time, which helps to quickly identify and respond to the environmental conditions at the laser demolition rescue site.

[0136] 3. Adaptive control technology: The collaborative controller of the laser controller and the signal acquisition unit uses the time-division multiplexing method to dynamically adjust the time of laser emission and signal acquisition, ensuring accuracy and avoiding crosstalk.

[0137] Application prospects of the present invention:

[0138] Combined with the multi-component gas dynamic imaging monitoring system of the present invention, it has the following key application prospects in the laser demolition rescue scenario:

[0139] 1. Real-time monitoring of dangerous gases: In laser demolition operations, it is crucial to monitor dangerous gases in real time, especially in environments where flammable, explosive or toxic gases may exist. The present invention can monitor and analyze the distribution and concentration of multiple gases, ensuring that rescue personnel can understand the real-time environmental conditions, avoid operating in areas with too high dangerous gas concentrations, and reduce potential safety risks.

[0140] 2. Improve rescue efficiency and safety: By using laser demolition technology, it is possible to precisely cut through sturdy structures such as concrete and metal, quickly opening up access to trapped individuals. Combined with the monitoring system of the present invention, rescue teams can conduct rescue operations more safely and effectively as they can receive visual information about gas concentration and distribution in real time and make timely adjustments to respond to emergencies.

[0141] 3. Rescue decision-making support: The system of the present invention can not only monitor gases, but also generate thermal images of gas distribution in real time through an image recording analyzer, providing intuitive data support for rescue teams. This information is crucial for formulating scientific rescue strategies, optimizing rescue routes, and evaluating the best locations for laser demolition.

[0142] 4. Expand the application scope: Since the present invention can remotely monitor and has high sensitivity and real-time response capabilities, it is applicable not only to mine and building collapse scenarios, but can also be extended to chemical accidents, earthquake rescue, and large-scale traffic accidents. For example, when an accident occurs in a chemical area, the system can remotely monitor and analyze the leakage and spread of hazardous chemicals, helping rescue teams effectively avoid or mitigate the impact of disasters.

[0143] 5. Prevention of secondary disasters: Laser demolition may cause the diffusion of gases or dust during operation. Using the monitoring system of the present invention can monitor these changes in real time and prevent possible secondary disasters such as explosions or further spread of toxic gases.

Claims

1. A multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue, characterized in that, The system comprises a laser emitting unit (1), a signal collecting unit (2), a signal processing unit (3) and an imaging unit (4); The laser emission unit (1) is used to generate and emit a laser signal of a specific wavelength to detect multi-component gases in a target environment; The signal acquisition unit (2) is used to receive the laser signal returned after passing through the target environment and convert it into an electrical signal; The signal processing unit (3) is used to analyze and process the electrical signal received from the signal acquisition unit, and extract an effective signal containing information on the concentration and type of laser hazardous gas; The imaging unit (4) is used to combine the processed signal data and convert it into a visual image or graphic output to generate a real-time multi-component gas distribution map; The four units collaborate through physical connections and signal transmission to complete the workflow of the entire system.

2. The multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue according to claim 1, wherein, The laser emission unit (1) outputs laser light of a wavelength range required for detecting target gas in the demolition area by a time-division multiplexing method, and emits the laser light to the detection area in a time-division manner. When the laser light passes through the detection area, gas molecules selectively absorb light matching their characteristic wavelength. The time division multiplexing method divides different signals into multiple time periods on the time axis, so that each signal is transmitted in sequence through the same transmission channel. This method divides the working time of the laser emission unit into different time periods, and each time period is allocated to a laser beam of a specific wavelength or a specific direction, thereby improving laser utilization, reducing interference and signal aliasing, and realizing the detection of multi-component gases.

3. The multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue according to claim 1, characterized in that, The laser emitting unit (1) outputs laser light in a wavelength range required for detecting target gas in the demolition area; The laser emitting unit (1) comprises a laser emitter (7), a laser controller (5) and a laser driver (6); The signal acquisition unit (2) comprises an analog-to-digital converter (14), a phase-locked amplifier (15), an image recording and analyzing device (16) and a display screen (17); The laser controller (5) and the laser driver (6) are connected in a two-wire manner through a BNC cable (18) and a multimode optical fiber (19). The laser driver is adjacent to the laser emitter (7) to drive it to generate a laser signal. The laser signal is collimated by a laser collimator (11) to ensure that the beam directions are consistent. The collimated laser beam is further focused by a Fresnel lens (12) and projected onto the target area. The cooperative controller (10) and the photodetector (13) are connected through a shielded cable (20). The reflected or scattered echo signal is received by the photodetector (13) arranged at the end of the optical path, and the optical signal is converted into an electrical signal. The photodetector (13) and the analog-to-digital converter (14) are connected through a BNC cable. The electrical signal is transmitted to the analog-to-digital converter (14) and converted into a digital signal. The analog-to-digital converter (14) and the lock-in amplifier (15) are connected through a shielded cable (20). The processed signal is analyzed and processed by the lock-in amplifier (15), and finally, dynamic imaging analysis is performed by the image recording and analyzer (16). The lock-in amplifier (15) and the image recording and analyzer (16) are connected through a BNC cable (18). The processed signal is displayed in real time on the display screen (17). The image recording and analyzer (16) and the display screen (17) are connected through an HDMI cable (21).

4. The multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue according to claim 3, characterized in that, The laser driver (6) includes a soft-start circuit (6-1). The soft-start circuit (6-1) is located at the front end of the laser driver and is directly connected to the constant-current circuit (6-2) through a cable. The constant-current circuit (6-2) is connected after the soft-start circuit (6-1) and is connected to the modulation signal circuit (6-3) and the laser cell (6-5) through a cable. The modulation signal circuit (6-3) is simultaneously connected to the feedback circuit (6-6). The protection circuit (6-4) is parallel to the laser cell (6-5) and other control circuits. The laser cell (6-5) is connected to the feedback circuit (6-6). The feedback circuit (6-6) is located at the output end of the laser cell, monitors the state of the laser output, and feeds back the information to the constant-current circuit and the modulation signal circuit. The laser emitter (7) is installed in the laser cell (6-5) of the laser driver (6). The current is gradually increased through the soft-start circuit (6-1) to protect the laser emitter (7). The stable operating current is maintained by the constant-current circuit (6-4), and the laser output is adjusted through the modulation signal circuit (6-3). The feedback circuit (6-6) monitors the laser power in real time to ensure stable output. The protection circuit (6-4) cuts off the power supply or reduces the current in case of an abnormality to prevent damage.

5. The multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue according to claim 3, characterized in that, The laser controller (5) includes a single-chip microcomputer (5-1) which is located at the front end of the laser controller and is connected to a digital potentiometer (5-2) and a signal adjuster (5-7) through data lines; the digital potentiometer (5-2) is connected between the single-chip microcomputer (5-1) and the power amplification module (5-3); the power amplification module (5-3) is located at the output end of the control system and is connected to the digital potentiometer (5-2); the thermoelectric cooler (5-4) is connected to the power amplification module (5-3) and the temperature sensor (5-5); the temperature sensor (5-5) feeds back temperature information to the analog-to-digital conversion module (5-6) through a data line; the analog-to-digital conversion module (5-6) is connected to the signal adjuster (5-7); the signal adjuster (5-7) is located at the output end of the power amplification module and is connected to the single-chip microcomputer (5-1) and an external laser emitter.

6. The multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue according to claim 5, characterized in that, The phase-locked amplifier (15) includes a signal generator (15-1) which is located at the input end of the phase-locked amplifier and is connected to a band-pass filter (15-2) through a signal line; the band-pass filter (15-2) receives the signal transmitted by the signal generator (15-1); the multiplier (15-3) receives the input signal from the band-pass filter (15-2) and at the same time receives a reference signal from the reference signal generator (15-8) for phase comparison, and the two input signals are connected to the multiplier through signal lines; the low-pass filter (15-4) is connected to the multiplier (15-3) through a signal line; the output amplifier (15-5) is connected to the low-pass filter (15-4) through a control signal line and is responsible for outputting the processed signal; the phase-locked loop (15-6) is connected to the reference signal generator (15-8) and the reference trigger (15-7) to lock the phase relationship between the reference signal and the input signal; the reference trigger (15-7) is connected to the phase-locked loop (15-6) and the reference signal generator (15-8).

7. A multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue according to claim 5, characterized in that, The image recording and analyzer (17) demodulates the input digital signals of different wavelengths to extract the frequency components related to the absorption peaks of the target gas; uses a known gas absorption spectral line library to match the detected spectral signal with the absorption spectrum of the reference gas, and determines the concentration and composition of the specific gas through a fitting algorithm; assigns different colors and brightness according to the different concentrations of the gas to generate a pseudo-color image.

8. A multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue according to claim 7, characterized in that, The image recording and analyzer (17) receives the digital signal transmitted by the signal processing unit (3), and this signal contains the information after the interaction between the laser of different wavelengths and the target gas when passing through the monitoring area. For each wavelength, the change in signal intensity corresponds to the concentration characteristics of the gas; Preprocess the input signal. First, perform a filtering operation to remove background noise and non-target frequency interference, and use a band-pass filter to select the frequency components related to the absorption peaks of the target gas. The filtering equation is: s f (t) = s(t) * h(t) where s f (t) is the output signal, s(t) is the output signal, h(t) is the impulse response of the band-pass filter, and * represents the convolution operation; In the frequency domain, it can be expressed as: S f (f) = S(f)·H(f) where S(f) is the Fourier transform of the input signal, and H(f) is the frequency response of the filter; Demodulate the filtered signal. The demodulation method uses a lock-in amplifier, that is, by synchronizing the phase of the reference signal with the input signal. The demodulated signal can be expressed as: V d v(t) = V f ·cos(ωt + φ) Among them, V f (t) is the filtered signal, ω is the angular frequency of the reference signal, and φ is the phase difference; After low-pass filtering, the DC component is obtained: where A is the signal amplitude, and cos(φ) reflects the phase relationship between the input signal and the reference signal; After demodulation, extract the frequency components related to the absorption peak of the target gas. Set the intensity of the laser signal after absorption as I, and its relationship can be described by the Lambert-Beer law: I = I0exp(-αCL) where I0 is the initial laser intensity, α is the absorption coefficient, C is the gas concentration, and L is the optical path length; Take the logarithm of the above formula and solve to obtain the gas concentration C expressed as: Collect the demodulated signals at different wavelengths λ to obtain the corresponding harmonic signal amplitudes; α is related to the absorption spectrum S(λ) in the standard absorption spectrum library: α = σ(λ) = S(λ) where σ(λ) is the absorption cross-section of the gas; The spectral signal obtained by demodulation: M(λ) = Kexp(-S(λ)CL) where K is a constant related to the system gain; Match the demodulated spectral signal M(λ) with the known gas absorption spectrum library S(λ). In the matching process, the least squares method is used for fitting analysis. The least squares objective function is: min k ∑ λ [M(λ) - kS(λ)] 2 where k is the parameter to be fitted, representing the scaling factor of the gas concentration. Take the derivative of the objective function with respect to k and set it equal to zero: Solve to obtain k: In the fitting process, the weighted least squares method is further used to increase the robustness of the fitting. The objective function of the weighted least squares method is: min k ∑ λ ω(λ)[M(λ)-kS(λ)] 2 where ω(λ) is the weight factor; Similarly, take the derivative of the objective function with respect to k and set it equal to zero, and solve to obtain k: In gas imaging, according to the gas concentration information obtained by fitting, map the concentration values of each gas to different colors and brightnesses to generate a pseudo-color image; Set the gas concentration range to [C min , C max , and use the method of linear mapping to map the concentration value to the brightness value B in the color space; Assign different colors to the concentrations of different gases, so as to form an intuitive pseudo-color distribution map in the image. Set the color values in the RGB color space as (R, G, B) = f(C); where f(C) is the color mapping function, which is used to calculate the corresponding RGB color values according to the gas concentration C.

9. A multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue according to claim 8, characterized in that, The specific mapping method adopts linear or non-linear interpolation methods; for a certain gas, use the following linear mapping: When C = C min then, (R, G, B) = (0, 0, 255) (blue) When C = C max , (R, G, B) = (255, 0, 0) (blue) The intermediate value is linearly interpolated according to the concentration ratio: G＝0 B = 255 - R The finally generated pseudo-color image is presented in real time through the display screen (17). The system updates the image of the retrieved multi-component gas concentration and distribution in real time, and automatically or manually marks the areas where the gas concentration exceeds the standard, helping the rescue team quickly identify potential hazard areas.

10. A method for using a multi-component gas dynamic imaging monitoring system applicable to laser demolition rescue according to any one of claims 1-9, characterized in that, Including the following steps: Step (1), starting the multi-component gas dynamic imaging monitoring system, performing pre-calibration, starting the laser controller (5) and the laser driver (6), ensuring that the laser signal emitted by the laser emitter (7) is stable after starting, adjusting the laser collimator (11) for collimating the laser beam to make the beam direction consistent, ensuring the subsequent laser transmission path is accurate, and starting the laser controller (5), wherein the temperature sensor (5-5) and the thermoelectric cooler (5-4) adjust the temperature of the laser emitter (7) in real time; Step (2), according to the actual situation of the laser demolition and rescue environment, adjust the position of the laser collimator (11) and the Fresnel lens (12) to ensure that the laser beam can cover all areas that need to be monitored; and adjust the optical path in real time in combination with the feedback information on site; Step (3), according to the actual situation of the laser demolition and rescue environment, the laser emitting unit (1) is used to emit laser beams of multiple wavelengths in different time periods through a time division multiplexing method, and the cooperative controller (10) cooperates with the photodetector (13) to ensure that the laser can be quickly switched between different wavelengths, and the photodetector (13) can respond immediately after the laser is emitted, and accurately collect the reflection signal of each wavelength; Step (4), configure the type and quantity of the gas to be detected in the system interface, input the known gas absorption spectrum data, and the analog-to-digital converter (14) and the phase-locked amplifier (15) work together to adjust the gain of the photodetector (13). If the signal strength is too low, the gain is gradually increased; if the signal strength is too high, the gain is reduced to reduce noise, ensuring that the system's signal processing module can accurately distinguish the absorption signals of different gases; Step (5), start the real-time monitoring mode, view the gas concentration change diagram in real time through the image recording analyzer (16) and the display screen (17), monitor the dynamic diffusion of dangerous gases, and according to the gas concentration distribution diagram and trend analysis results generated by the system, the on-site rescue personnel can adjust the rescue strategy in time, optimize the rescue path and plan, and ensure the safety and efficiency of the rescue process; When the gas concentration in a certain area is detected to be excessive, the display screen (17) will automatically mark the dangerous area, helping the rescue team to quickly identify potential hazards and take corresponding countermeasures.

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