Miniaturized hyperspectral trace gas remote sensing instrument for on-board underway use

Abstract

The application discloses a kind of miniaturized hyperspectral trace gas remote sensing instruments for vehicle navigation, comprising: shell, by 3D printing from light material quality, and by heat baffle the shell is spaced into two chambers;Optical acquisition system, including: by acquisition optical path unit acquisition solar scattered light is transmitted to high-resolution spectrometer by optical fiber and forms spectrum;Control system, including: driving unit is used to control the collection angle and precision of acquisition optical path unit, temperature control unit is used to stabilize the working temperature of high-resolution spectrometer to ensure that high-quality spectrum is formed, power supply unit is used to provide electrical energy for system, communication and positioning unit is used to realize the communication of instrument and outside and instrument positioning, main control unit is arranged in another chamber and is used to control other units in system and high-resolution spectrometer work.The instrument is small in size, light in weight, and is carried on mobile platform such as car, ship and the like to realize trace gas remote sensing.

Description

Technical Field

[0001] This invention belongs to the field of hyperspectral remote sensing for detecting polluting gases, specifically relating to a miniaturized hyperspectral trace gas remote sensing instrument for vehicle-mounted mobile applications. Background Technology

[0002] Air pollution is a complex mixture of various substances that harms the health of humans, animals, and plants. Air pollutants can take many forms, such as gases, solid particles, or liquid droplets. Some common air pollutants include carbon monoxide, lead, nitrogen oxides, ground-level ozone, particulate matter, and sulfur oxides. Particulate pollution consists of many components, including acids (such as nitrates and sulfates), organic chemicals, metals, and soil or dust particles. Trace gases are also composed of many components; they refer to particles in the atmosphere with concentrations below 10E-6. Examples of trace gases include CO, N₂O, SO₂, O₃, NO, NO₂, CH₄, NH₃, H₂S, halides, and organic compounds. These trace particles are affected by various physical, chemical, biological, and terrestrial processes and participate in biogeochemical cycles, significantly impacting the global atmospheric environment and ecology. For example, acid rain, the greenhouse effect, and ozone layer depletion are all related to trace gases.

[0003] In recent years, with the continuous improvement of urban industrialization, air pollution has gradually intensified, exhibiting characteristics such as wide spatial distribution, high complexity, and high temporal variability. Air pollutants in the atmosphere have a significant impact on people's lives and health. To effectively control air pollution, it is necessary to accurately monitor the concentration and spatiotemporal distribution of air pollutants. Rapid and precise source tracing is of paramount importance for air pollution prevention and control.

[0004] Traditional atmospheric pollution sampling and detection primarily relies on ground-based instruments, which are fixed at observation points for long-term monitoring. While these instruments offer high accuracy, their immobility limits their ability to perform large-scale measurements, and the measurement methods are complex, making it impossible to obtain real-time and accurate information on the distribution and changes of air pollution within a given area. In contrast, remote sensing instruments utilizing differential absorption spectroscopy (DIS) technology can perform continuous, long-term, multi-component environmental pollution monitoring over a larger spatial area, and can achieve completely non-contact measurement, thus expanding the application scenarios for atmospheric pollutant gas detection.

[0005] For current mainstream hyperspectral instruments, they are large in size and weight, have high power consumption, and low circuit integration, making them inconvenient to mount on mobile platforms such as small cars for measurement. At the same time, they generally use a combination of prism and lens optical path, and the scattered light is guided into the receiving telescope through the right-angle prism, which requires an extra reflection, resulting in a low overall signal-to-noise ratio, large measurement error, and low spectral utilization efficiency. Summary of the Invention

[0006] In view of the above, the purpose of this invention is to provide a miniaturized hyperspectral trace gas remote sensing instrument for vehicle-mounted mobile applications, which can be mounted on mobile platforms such as automobiles and ships to achieve trace gas remote sensing due to its small size and light weight.

[0007] To achieve the above-mentioned objectives, this invention provides a miniaturized hyperspectral trace gas telemetry instrument for vehicle-mounted mobile surveillance, comprising:

[0008] The shell is made of lightweight material and 3D printed, and is divided into two chambers by heat insulation baffles;

[0009] An optical acquisition system includes an acquisition optical path unit, an optical fiber, and a high-resolution spectrometer placed in a cavity. The solar scattered light acquired by the acquisition optical path unit is transmitted through the optical fiber to the high-resolution spectrometer to form a spectrum.

[0010] The control system includes a drive unit, a temperature control unit, a power supply unit, a communication and positioning unit, and a main control unit. The drive unit is used to control the acquisition angle and accuracy of the acquisition optical path unit. The temperature control unit is used to stabilize the operating temperature of the high-resolution spectrometer to ensure the formation of high-quality spectra. The power supply unit is used to provide power to the system. The communication and positioning unit is used to realize the communication between the instrument and the outside world and the instrument positioning. The main control unit is located in another chamber and is used to control the operation of other units in the system and the high-resolution spectrometer.

[0011] Preferably, the shell is made of ABS material and is manufactured by 3D printing technology using fused deposition modeling. The overall weight of the shell is no more than 600g and the average thickness is less than 3mm.

[0012] Preferably, the optical path unit is an integrated barrel-type optical path, specifically a lens group formed by plano-convex lenses and fixed to a lens group bracket, used to collect solar scattered light and focus it onto the fiber optic port;

[0013] It also includes a threaded focusing structure set on the periphery of the lens group. The position and rotation angle of the lens group can be adjusted along the optical axis by the threaded focusing structure. After the position and angle are fixed, they can be locked with an external retaining ring.

[0014] Preferably, the drive unit includes a servo stepper motor, a six-axis attitude sensor, a reducer, and a drive circuit. The servo stepper motor is fixed to the outside of the housing, and a reducer is connected to the servo stepper motor. A lens group bracket is fixed on the rotation shaft of the reducer. The six-axis attitude sensor is fixed on the lens group bracket. The drive circuit is used to calculate and filter the attitude information collected by the six-axis attitude sensor to form a measurement angle, and to drive the rotation of the servo stepper motor in real time based on the measurement angle, thereby driving the lens group on the lens group bracket to collect solar scattered light at different angles.

[0015] Preferably, the temperature control unit includes a temperature sensor, a thermoelectric cooler, and a temperature control circuit. The thermoelectric cooler is closely connected to the high-resolution spectrometer. The temperature sensor is placed between the thermoelectric cooler and the high-resolution spectrometer and is used to measure the temperature. The temperature control circuit is used to calculate the cooling power applied to the thermoelectric cooler based on the measured temperature using a PID control algorithm, and outputs a control current to the thermoelectric cooler based on the cooling power to achieve stable closed-loop control of the thermoelectric cooler.

[0016] Preferably, the outer wall of the housing on the side where the high-resolution spectrometer is located is also fixed with heat sinks and a large cooling fan to dissipate heat from the chamber containing the high-resolution spectrometer.

[0017] Preferably, the power supply unit includes a battery module and a voltage conversion circuit. The battery module is fixed to the outside of the housing by a battery fixing structure and connected to the voltage conversion circuit located in the chamber through a power supply inlet structure. The voltage conversion circuit performs voltage regulation and step-down processing on the voltage output by the battery module to output stable voltages in multiple modes, including 12V, 5V, 3.8V and 3.3V.

[0018] Preferably, the main control unit includes a small mobile PC and a main control circuit located in another chamber. The small mobile PC and its main control circuit are used to control the operation of the drive unit, temperature control unit, power supply unit, communication and positioning unit, as well as the spectral acquisition achieved by the optical acquisition unit and high-resolution spectrometer. They are also used to record the GPS information of the GPS module, save the instrument's log records, and display the measurement results and spectral inversion results.

[0019] Preferably, the communication and positioning unit includes a serial communication module, a GPS module, and a cellular network communication module. The serial communication module is used to realize the communication and transmission of control information and collected data between the small mobile PC and each unit. The GPS module is located on the housing and is used to realize the instrument positioning and obtain GPS information. The cellular network communication module is used to realize the communication and transmission of measurement result data and inversion result data of the small mobile PC with external devices.

[0020] Preferably, the high-resolution spectrometer has different slit widths, and the requirements for different resolutions and light intake can be met by changing the slit width.

[0021] The advantages of this invention compared to existing technologies are:

[0022] By redesigning the optical acquisition system, the signal-to-noise ratio of the instrument can be improved while maintaining resolution, thus enhancing the accuracy of the instrument when measuring trace gases. Lens groups with different diameters and field of view are provided, enabling applications in a wider range of scenarios. Simultaneously, the miniaturized and integrated design reduces the size and weight of the instrument, making it more flexible and convenient, and broadening its application range. The main control unit enables one-click plotting, quickly obtaining measurement results, and real-time acquisition of GPS information and instrument operation logs during instrument navigation, improving the instrument's convenience and practicality. Furthermore, the communication design utilizes a cellular network for data transmission, enabling real-time remote control and monitoring. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the principle structure of a miniaturized hyperspectral trace gas telemetry instrument for vehicle-mounted mobile applications provided in the embodiment.

[0025] Figure 2-4 This is a schematic diagram of the structure of a miniaturized hyperspectral trace gas telemetry instrument for vehicle-mounted mobile applications provided in the embodiment, wherein, Figure 2 Top view of the instrument with the cover removed. Figure 3 This is the rear view of the instrument. Figure 4 It is a partial schematic diagram of the instrument's optical acquisition path unit and a cross-sectional view of the drive unit;

[0026] Figure 5 This is a flowchart of the instrument usage provided in the embodiment;

[0027] Figure 6 This is a schematic diagram of the instrument measurement results provided in the embodiment;

[0028] The components include: 1. Optical acquisition module; 2. Small mobile PC; 3. Temperature control circuit board; 4. Main control circuit board; 5. Heat insulation baffle; 61. GPS module; 62. Cellular network module; 7. Semiconductor cooling chip; 8. High-resolution spectrometer; 9. Heat sink; 10. Large cooling fan; 11. Small cooling fan; 12. Small cooling fan; 13. Battery module; 14. Servo stepper motor; 15. Optical fiber; 16. Battery fixing structure; 17. Power supply input structure; 18. Six-axis attitude sensor; 19. Instrument switch; 20. Instrument top cover; 21. Instrument shell; 22. Reducer; 23. Lens group bracket; 24. Lens group; 25. Temperature sensor; 26. Drive circuit; 27. Voltage conversion circuit. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the scope of protection of this invention.

[0030] The technical concept of this invention is as follows: In order to solve the problems of large size and insufficient integration of current hyperspectral remote sensing instruments, which result in bloated and unportable instrument systems, inflexible application in field environmental monitoring, inability to achieve rapid deployment, and inability to meet specified test requirements, this invention provides a miniaturized hyperspectral trace gas remote sensing instrument for vehicle-mounted mobile applications, which can be mounted on mobile platforms such as automobiles and ships for trace gas remote sensing.

[0031] like Figure 1 As shown, the system includes a housing 21, an optical acquisition system, and a control system. The housing 21 is made of lightweight material through 3D printing, specifically using 3D-printed ABS material with a density of only 1.05 g / cm³. 3 Specifically manufactured using fused deposition modeling (FDM) 3D printing technology, this significantly reduces weight and volume compared to the stainless steel and rigid plastic shells used in traditional hyperspectral remote sensing equipment. Furthermore, a special reinforced structural design incorporates reinforcing ribs in areas requiring significant load-bearing capacity, ensuring the shell maintains a certain level of horizontal rigidity and preventing deformation. While maintaining the shell's rigidity and hardness, the overall volume and thickness are minimized, with a minimum thickness of only 2mm and an average thickness of only 3mm, resulting in a total shell weight of no more than 600g. A heat-insulating baffle 5 divides the shell into two chambers, ensuring the high-resolution spectrometer within each chamber meets the requirements for accurate temperature control.

[0032] like Figure 2-4As shown, the optical acquisition system includes an acquisition optical path unit 1, an optical fiber 15, and a high-resolution spectrometer 8. Sunlight scattered by the acquisition optical path unit 1 is transmitted through the optical fiber 15 to the high-resolution spectrometer 8 to form a spectrum. Specifically, the high-resolution spectrometer 8 is fixed in a heat-insulated chamber within the housing, recording the acquired spectral information. It can measure the characteristic absorption of trace gases in the 290-410 nm range and use this information for subsequent software processing and inversion. The optical fiber connects the lens to the spectrometer, using an SMA905 interface. It needs to be compatible with the spectrometer's slit width. This system provides interchangeable slit widths to meet different resolution and light intake requirements.

[0033] like Figure 4 As shown, the acquisition optical path unit 1 is an integrated barrel-type acquisition optical path, used in scenarios requiring high integration and easy-to-fix acquisition platform for acquisition and measurement. The integrated barrel-type acquisition optical path uses a lens group 24 with a plano-convex lens design. The lens group is fixed on a lens group bracket 23 and is used to acquire solar scattered light from a designated area, focusing it onto the fiber optic port 15 before transmitting it to the high-resolution spectrometer 8 for acquisition. After being focused by the lens group 24, the solar scattered light has a spot height of 0.5mm at the focal point, demonstrating good focusing effect. Different barrels with varying field of view and diameters are provided for interchangeability to meet the needs of different application scenarios. Specifically, a threaded focusing structure is designed around the lens group, allowing adjustment of the lens group's position and rotation angle along the optical axis. After fixing the position and angle, it can be locked with an external clamping ring. The lens group allows control of the instrument's field of view up to 0.7°, increasing the instrument's spatial resolution. Simultaneously, the maximum diameter of the lens group is only 25.4mm, and the weight can be kept below 80g.

[0034] Existing optical systems primarily acquire spectra using a right-angle prism, plano-convex lens, and optical fiber. This invention, however, mainly employs a plano-convex lens and optical fiber, eliminating the need for a quartz right-angle prism. Quartz glass has a transmittance of approximately 90% in the ultraviolet band, which reduces light intensity and thus signal strength. The overall noise of the instrument includes both optical and electronic noise from the circuitry. Eliminating the right-angle prism improves the signal-to-noise ratio to some extent.

[0035] The control system includes a drive unit, a temperature control unit, a power supply unit, a communication and positioning unit, and a main control unit. The drive unit controls the acquisition angle and accuracy of the optical path unit. For example... Figure 2-4As shown, the drive unit includes a servo stepper motor 14, a six-axis attitude sensor 18, a reducer 22, and a drive circuit. The servo stepper motor 14 is fixed to the outside of the housing, and the reducer 18 is connected to the servo stepper motor 14. The servo stepper motor 14 and the reducer 18 are connected and fixed together on the housing to increase the rotational torque and achieve precise rotation control with a minimum rotation angle of 0.01°. A lens group bracket 23 is fixed on the rotation axis of the reducer 18. The six-axis attitude sensor 18 is fixed on the lens group bracket 23 and is used to measure the pitch angle during observation and feed it back to the drive circuit 26 for real-time control. The drive circuit 26 is used to solve and filter the attitude information collected by the six-axis attitude sensor 18 to form a measurement angle with an accuracy of ±0.1°. Based on the measurement angle, the drive circuit drives the rotation of the servo stepper motor 14 in real time, which can achieve precise rotation from -90° to 90° with a response speed of less than 1 second. This, in turn, drives the lens group 24 on the lens group bracket 23 to collect solar scattered light at different angles.

[0036] The temperature control unit is used to stabilize the operating temperature of the high-resolution spectrometer to ensure the formation of high-quality spectra. For example... Figure 2-4 As shown, the temperature control unit includes a temperature sensor 25, a thermoelectric cooler 7, and a temperature control circuit 3. The thermoelectric cooler 7 is tightly connected to the high-resolution spectrometer 8. The temperature sensor 25 is placed between the thermoelectric cooler 7 and the high-resolution spectrometer 8 and is used to measure the temperature. The temperature measurement range is -10°C to 85°C, and the error can be controlled within ±0.5°C. The value measured by the temperature sensor 25 is transmitted as feedback to the temperature control circuit 3. The temperature control circuit 3 calculates the cooling power applied to the thermoelectric cooler 7 based on the measured temperature using a PID control algorithm. Based on the cooling power, a designed filter circuit converts the AC control voltage into DC output to the thermoelectric cooler 7 to achieve stable closed-loop control of the thermoelectric cooler. The temperature control accuracy depends on the measurement accuracy of the temperature sensor 25. The cavity formed by the heat insulation baffle and the outer shell is a relatively sealed heat insulation chamber used for temperature control of the high-resolution spectrometer 8. At the same time, the thermoelectric cooler 7 is used to increase the cooling area, which can keep the spectrometer temperature below 22°C. The thermoelectric cooler 7 can be made of aluminum alloy heat-conducting plate.

[0037] To dissipate heat from the insulated chamber, a heat sink 9 and a large cooling fan 10 are fixed to the outer wall of the casing on that side, thus cooling the chamber housing the high-resolution spectrometer 8. The heat sink 8 can be made of aluminum alloy. Additionally, small cooling fans 11 and 12 are also included on the outer side of the casing. A temperature control unit is installed inside the casing, paired with a high-precision temperature sensor, to achieve closed-loop temperature control of the spectrometer, reducing its thermal noise.

[0038] The power supply unit is used to provide electrical energy to the system. For example... Figure 2-4As shown, the system specifically includes a battery module and a voltage conversion circuit 27. The battery module 13 is fixed to the outside of the housing via a battery fixing structure 16 and connected to the voltage conversion circuit located in the chamber via a power supply inlet structure 17. The voltage conversion circuit 27 performs DC-DC voltage regulation and step-down processing on the voltage output from the battery module to output stable voltages in multiple modes, including 12V, 5V, 3.8V, and 3.3V. The battery module 13 uses a lithium battery and is fixed to the outside of the housing via the battery fixing structure 16 for easy and quick battery replacement during operation.

[0039] The communication and positioning unit is used to enable communication between the instrument and the external environment, and to locate the instrument. For example... Figure 2-3 As shown, it specifically includes a serial communication module, a GPS module 61, and a cellular network communication module 62. The serial communication module is used to realize the communication and transmission of control information and collected data between the small mobile PC and each unit. The GPS module 61 is located on the housing and is used to realize the instrument positioning and obtain GPS information. The cellular network communication module 62 is used to realize the communication and transmission of measurement result data and inversion result data of the small mobile PC with external devices.

[0040] The main control unit is located in another chamber and is used to control the operation of other units in the system and the high-resolution spectrometer. For example... Figure 2 and 3 As shown, it specifically includes a small mobile PC 2 and a main control circuit 3 located in another chamber. The small mobile PC 2 and its main control circuit 3 are used to control the operation of the drive unit, temperature control unit, power supply unit, communication and positioning unit, as well as the spectral acquisition achieved by the optical acquisition unit and high-resolution spectrometer. They are also used to record the GPS information of the GPS module, save the instrument's log records, and display the measurement results and the real-time inversion results based on the spectrum.

[0041] The instrument also has an instrument switch 19 and an instrument top cover 20 on its outer shell. All components are fixed with screws. All components are small in size, so that the overall weight of the instrument is kept within 3kg.

[0042] Traditional hyperspectral measurement instruments involve cumbersome acquisition and control processes, requiring the use of multiple software programs. This leads to complex and inefficient operation. Furthermore, the data acquired by the acquisition software requires subsequent processing and inversion to obtain measurement results, hindering real-time plotting and rapid response. The operation of multiple software programs also places certain demands on the host computer's performance, making smooth operation on miniaturized computers impossible. This invention utilizes independently developed measurement software, enabling seamless hardware and software collaboration. A designed communication protocol facilitates rapid data transmission between the host and slave computers, ensuring data stability. Simultaneously, a single software program manages elevation angle control, spectral acquisition, result display, and log recording. Combined with automated scripts, it achieves result inversion and real-time plotting, resulting in convenient operation and rapid feedback of measurement results. The software acquisition and inversion program flow is as follows: Figure 5 As shown.

[0043] The specific operating procedure of the aforementioned miniaturized hyperspectral trace gas detector for vehicle-mounted mobile monitoring is as follows: First, the instrument is fixed on the mobile platform, and the integrated cannon-shaped optical path structure can be fixed to the instrument shell. The optical acquisition system collects solar scattered light spectra at multiple observation elevation angles. The typical operating elevation angle sequence is 90°, 30°, 30°, and 30°. The 90° spectrum is generally used as a reference spectrum. After deducting the influence of the stratosphere, the spectra at multiple 30° elevation angles are used to calculate the column concentration and generate the final mobile monitoring concentration distribution map. At the start of operation, automatic acquisition mode is used to collect the oblique column concentration at the target observation point at the specified elevation angle, and the shape of the collected spectrum is displayed in real time, recording the current environmental monitoring data of the instrument. As the mobile platform moves forward, the target range of the instrument is continuously updated, and the GPS information of the mobile platform's movement is recorded. After the acquisition is completed, automated result inversion is performed to generate concentration distribution maps for different pollutant gas components. The vehicle-mounted mobile monitoring NO2 concentration distribution map obtained using this instrument is shown below. Figure 6 As shown.

[0044] The aforementioned instrument, through circuit integration and structural improvements, solves the problems of low integration and excessive size in existing environmental monitoring instrument systems, enabling it to be mounted on small mobile platforms such as automobiles for operation. The accompanying optical path system is an integrated, barrel-type optical path system integrated with the instrument, achieving gas detection functions at a lower cost and smaller size. Combined with improved control algorithms, the instrument system's accuracy is also enhanced, with the root mean square value reaching the 1E-4 level. Furthermore, by reducing system power consumption, the entire system can be powered by a lithium battery, improving its usability.

[0045] The specific embodiments described above illustrate the technical solution and beneficial effects of the present invention in detail. It should be understood that the above description is only the most preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, additions, and equivalent substitutions made within the scope of the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A miniaturized hyperspectral trace gas telemetry instrument for vehicle-mounted mobile applications, characterized in that, include: The shell is made of lightweight material and 3D printed, and is divided into two chambers by heat insulation baffles; An optical acquisition system includes an acquisition optical path unit, an optical fiber, and a high-resolution spectrometer housed in a chamber. The solar scattered light acquired by the acquisition optical path unit is transmitted through the optical fiber to the high-resolution spectrometer to form a spectrum. The acquisition optical path unit is an integrated barrel-type acquisition optical path, specifically a lens group formed by plano-convex lenses and fixed to a lens group bracket. It is used to collect solar scattered light and focus it onto the optical fiber port. It also includes a threaded focusing structure set on the periphery of the lens group. The position and rotation angle of the lens group can be adjusted along the optical axis through the threaded focusing structure. After the position and angle are fixed, they can be locked with an external clamping ring. The control system includes a drive unit, a temperature control unit, a power supply unit, a communication and positioning unit, and a main control unit. The drive unit is used to control the acquisition angle and accuracy of the acquisition optical path unit. The temperature control unit is used to stabilize the operating temperature of the high-resolution spectrometer to ensure the formation of high-quality spectra. The power supply unit is used to provide power to the system. The communication and positioning unit is used to realize the communication between the instrument and the outside world and the instrument positioning. The main control unit is located in another chamber and is used to control the operation of other units in the system and the high-resolution spectrometer. The drive unit includes a servo stepper motor, a six-axis attitude sensor, a reducer, and a drive circuit. The servo stepper motor is fixed to the outside of the housing, and a reducer is connected to the servo stepper motor. A lens group bracket is fixed on the rotation shaft of the reducer. The six-axis attitude sensor is fixed on the lens group bracket. The drive circuit is used to calculate and filter the attitude information collected by the six-axis attitude sensor to form a measurement angle, and to drive the rotation of the servo stepper motor in real time based on the measurement angle, thereby driving the lens group on the lens group bracket to collect solar scattered light at different angles.

2. The miniaturized hyperspectral trace gas telemetry instrument for vehicle-mounted mobile surveillance according to claim 1, characterized in that, The shell is made of ABS material and is produced by 3D printing technology using fused deposition modeling. The overall weight of the shell is no more than 600g and the average thickness is less than 3mm.

3. The miniaturized hyperspectral trace gas telemetry instrument for vehicle-mounted mobile applications according to claim 1, characterized in that, The temperature control unit includes a temperature sensor, a thermoelectric cooler, and a temperature control circuit. The thermoelectric cooler is closely connected to the high-resolution spectrometer. The temperature sensor is placed between the thermoelectric cooler and the high-resolution spectrometer and is used to measure the temperature. The temperature control circuit is used to calculate the cooling power applied to the thermoelectric cooler based on the measured temperature using a PID control algorithm. Based on the cooling power, it outputs a control current to the thermoelectric cooler to achieve stable closed-loop control of the thermoelectric cooler.

4. The miniaturized hyperspectral trace gas telemetry instrument for vehicle-mounted mobile applications according to claim 1, characterized in that, The outer wall of the housing on the side where the high-resolution spectrometer is located is also fixed with heat sinks and a large cooling fan to dissipate heat from the chamber containing the high-resolution spectrometer.

5. The miniaturized hyperspectral trace gas telemetry instrument for vehicle-mounted mobile applications according to claim 1, characterized in that, The power supply unit includes a battery module and a voltage conversion circuit. The battery module is fixed to the outside of the housing by a battery fixing structure and connected to the voltage conversion circuit located in the chamber through a power supply inlet structure. The voltage conversion circuit performs voltage regulation and step-down processing on the voltage output by the battery module to output stable voltages in multiple modes, including 12V, 5V, 3.8V and 3.3V.

6. The miniaturized hyperspectral trace gas telemetry instrument for vehicle-mounted mobile applications according to claim 1, characterized in that, The main control unit includes a small mobile PC and a main control circuit located in another chamber. The small mobile PC and its main control circuit are used to control the operation of the drive unit, temperature control unit, power supply unit, communication and positioning unit, as well as the spectral acquisition achieved by the optical acquisition unit and high-resolution spectrometer. It is also used to record the GPS information of the GPS module, save the instrument's log records, and display the measurement results and spectral inversion results.

7. The miniaturized hyperspectral trace gas telemetry instrument for vehicle-mounted mobile applications according to claim 6, characterized in that, The communication and positioning unit includes a serial communication module, a GPS module, and a cellular network communication module. The serial communication module is used to realize the communication and transmission of control information and collected data between the small mobile PC and each unit. The GPS module is located on the housing and is used to realize the instrument positioning and obtain GPS information. The cellular network communication module is used to realize the communication and transmission of measurement result data and inversion result data of the small mobile PC with external devices.

8. The miniaturized hyperspectral trace gas telemetry instrument for vehicle-mounted mobile applications according to claim 1, characterized in that, The high-resolution spectrometer has different slit widths, and different resolution and light intake requirements can be met by changing the slit width.

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