Self-research high-dimensional gas sensor array instrument

Abstract

The invention discloses a self-research high-dimensional gas sensor array instrument, which comprises a bottom shell, a top shell, a sucking pump, an array test module and a 88 channel signal acquisition card, and is characterized in that the bottom shell is provided with a fixed limiting screw stud, a polytetrafluoroethylene gasket, a connecting bayonet, a network cable opening, a power line opening and a gas inlet and outlet pipe opening; the top shell is provided with a connecting bayonet and a fixed limiting nut column, and the array test module comprises a test cavity, a test circuit board, a fixed base, a multi-channel numerical control power supply, a gas sampling module, a high-dimensional gas sensor array module, a signal processing module, a data transmission module and a visual software module. According to the invention, a high-dimensional gas sensor array is combined with a real-time visualization technology for the first time, an integrated solution from gas sampling, detection, signal processing, data transmission to result visualization is realized, the limitation of single function of traditional gas detection equipment is broken through, and wide application prospects and important scientific values are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of gas detection, in particular to a high-dimensional gas sensor array instrument, which can be widely applied in the fields of in vitro diagnosis, public safety, food industry, etc., and is especially suitable for target individual identification and feature characterization research based on gas print characteristics, early disease screening, food quality detection, etc. BACKGROUND

[0002] In modern medicine and many industrial fields, gas detection technology plays an important role. However, the existing gas detection technology has many defects. In the aspect of in vitro diagnosis, traditional methods such as biochemical analysis based on blood, urine and other body fluids have the problems of invasive sample collection, complex detection process, dependence on large equipment, long cycle and high cost. Volatile organic compounds (VOCs) produced by human metabolism as important "biomarkers" can reflect physiological and pathological states, but the existing detection technology cannot meet the needs.

[0003] Although gas chromatography-mass spectrometry (GC-MS) is the "gold standard" for VOCs detection, it is large in equipment, complex in operation, long in detection time (more than 30 minutes) and high in cost, and cannot be used for on-site rapid diagnosis. Commercial electronic nose equipment has low sensor array dimension (usually less than 10 sensors), limited resolution for complex VOCs mixed systems, insufficient specificity, and is easily disturbed by the environment. At the same time, the existing detection system lacks special visual analysis software, and the data processing relies on manual operation by professional personnel, which is low in efficiency and difficult to intuitively present the detection results and support clinical decision-making.

[0004] Therefore, the existing equipment cannot meet the needs of target individual identification and feature characterization research based on gas print characteristics, and it is urgent to independently develop a high-dimensional gas sensor array instrument and supporting visual software. SUMMARY

[0005] In order to overcome the shortcomings of the prior art, the present application provides a self-developed high-dimensional gas sensor array instrument, which aims to solve the problems of limited detection range, insufficient precision, slow response, complex operation, lack of special visual analysis software, etc. in the existing gas detection technology, and to realize high sensitivity, high selectivity, multi-dimensional real-time detection and analysis of human-related volatile organic compounds, and to intuitively present the detection results, thereby providing strong support for related research and application.

[0006] The present application is realized by the following technical solutions:

[0007] The application discloses a self-developed high-dimensional gas sensor array instrument, which comprises a bottom shell, a top shell, a gas suction pump, an array test module, an 88-channel signal acquisition card, the bottom shell is provided with a fixed limiting screw column, a polytetrafluoroethylene gasket, a connecting bayonet, a network cable opening, a power cable opening and an air inlet and outlet pipe, the top shell is provided with a connecting bayonet and a fixed limiting nut column, the array test module comprises a test cavity, a test circuit board, a fixed base, a multi-channel numerical control power supply, a gas sampling module, a high-dimensional gas sensor array module, a signal processing module, a data transmission module and a visualization software module, through the cooperation of the modules, high sensitivity, high selectivity, multi-dimensional real-time detection and analysis of human body related volatile organic compounds can be realized, and the detection results can be intuitively presented.

[0008] Preferably, the gas sampling module is connected with the high-dimensional gas sensor array module through a pipeline, the output end of the high-dimensional gas sensor array module is connected with the input end of the signal processing module, the signal processing module communicates with a computer installed with the visualization software module through the data transmission module; the gas sampling module adopts a micro-pump suction sampling mode, the sampling flow can be adjusted in the range of 0.2L-3.0L / min, the sampling head has dustproof and moisture-proof functions, and the sampling pipeline is made of polytetrafluoroethylene; the high-dimensional gas sensor array module is composed of more than 80 sensors based on different metal oxide semiconductors and having different gas selectivity, and adopts compact arrangement; the signal processing module comprises a preamplifier, a filter and an analog-to-digital converter; the data transmission module adopts network cable transmission, and the transmission rate is greater than or equal to 100Mbps; the visualization software module can realize real-time analysis and visual presentation of the detection data, and the response speed is less than or equal to 0.5s.

[0009] Preferably, the gas suction pump adopts a brushless micro gas suction pump, and the brushless micro gas suction pump controls the gas flow rate to be 0.2-2000sccm.

[0010] Preferably, the 88-channel signal acquisition card is constructed with AD7606, AD7616 and STM32, and is used for multi-channel sensor signal synchronous acquisition and data transmission through a network port. The test cavity is made of polytetrafluoroethylene, and includes a bottom structure and a top cover plate structure. The bottom structure is integrally formed with the upper surface of the test circuit board, and both the bottom structure and the top cover plate structure are provided with 12 screw holes with a diameter of 3 mm. The screw holes are annularly distributed with centers coinciding with the center of the test cavity, and the distance between adjacent screw holes is 25 mm. The bottom structure and the top cover plate structure are sealingly connected by 12 M3x15mm screws inserted into the screw holes. The volume of the test cavity after sealing is 20 mL. The middle part of the left side wall of the test cavity is provided with an air inlet, and the middle part of the right side wall is provided with an air outlet. The inner diameters of the air inlet and the air outlet are both 8 mm, and the interface types are both pagoda joints. The front end of the air inlet is provided with a flowmeter, which controls the gas flow rate at 0.5-2 L / min. The working power of the air pump is adjusted to 1-10 W.

[0011] Preferably, the multi-channel numerical control power supply uses the microprocessor STM32F103ZET6 newly launched by ST Microelectronics as the main control chip, with a power supply voltage of 2V-3.6V. It uses a 32-bit high-performance ARM Cortex-M3 RISC core, has a rich enhanced I / O port and peripherals connected to two APB buses, supports serial single-wire debugging (SWD) and JTAG interface debugging, and can directly obtain debugging information from the CPU using JTAG.

[0012] Preferably, the gas sampling module uses a micro-pump suction sampling method, and the sampling flow rate can be adjusted within the range of 0.2L-3.0L / min, which can be flexibly adjusted according to different detection requirements. The sampling head is designed to have a dustproof and moisture-proof structure, which can effectively prevent dust and moisture in the external environment from polluting the collected gas samples, ensuring the authenticity and accuracy of the samples. The sampling pipeline is made of polytetrafluoroethylene, which has stable chemical properties and can reduce the adsorption and loss of gas during transmission, ensuring the integrity of the gas samples.

[0013] Preferably, the high-dimensional gas sensor array module is composed of 80 sensors based on different metal oxide semiconductors, each of which has different gas selectivity and can produce specific response to different kinds of gas components, thereby realizing detection of multiple volatile organic compounds. The arrangement of the sensor array adopts a compact design, which reduces the size of the device while ensuring sufficient contact between the gas and each sensor and improving the accuracy of detection. The module can detect human-related volatile organic compounds with a concentration range of 0.05-1000 ppm and a detection lower limit of ≤500 ppb, and the response / recovery time is ≤30 s.

[0014] Preferably, the signal processing module includes a preamplifier, a filter, and an analog-to-digital converter. The preamplifier can amplify the weak electrical signal output by the sensor to a range that can be recognized by the analog-to-digital converter for subsequent processing. The filter can remove environmental noise and sensor noise to ensure the purity of the signal. The analog-to-digital converter accurately converts the analog electrical signal into a digital signal through sampling, quantization, and coding, laying the foundation for data transmission and analysis.

[0015] Preferably, the data transmission module uses a network cable for data transmission with a transmission rate of ≥100 Mbps, which can meet the real-time transmission requirements of gas-sensitive detection data and ensure the timeliness of the detection results.

[0016] Preferably, the visualization software module is self-developed and can perform real-time analysis and visualization of the digital signals obtained during gas-sensitive detection. The software supports preselected channels, setting data storage paths, and sampling frequencies, and can intuitively display the gas concentration change trend and related data characteristics, making it easy for operators to quickly grasp the detection dynamics and make analysis and judgments, with a response speed of ≤0.5 s.

[0017] Preferably, the test circuit board is connected to the 88-channel signal acquisition card through six data lines, which are used to transmit test control signals and test data. The substrate of the 88-channel signal acquisition card is a silica gel plate with dimensions of 100 mm x 80 mm and a thickness of 2 mm. Six layers of data acquisition circuits are stacked on the upper surface of the silica gel plate from bottom to top, with a thickness of 0.1 mm each. The layers are interconnected through vias with a diameter of 0.2 mm, and the inner wall of the via is plated with copper with a thickness of ≥20 μm. Each layer of circuit corresponds to 16 independent signal acquisition channels, with a total of 88 channels. The silica gel plate of the 88-channel signal acquisition card is provided with an RJ45 data transmission network port, which is arranged at the center of the right edge of the silica gel plate and adopts a shielded design in accordance with the IEC60603-7 standard. The network port is connected to a computer through a CAT5e class super five-class network cable, with a data transmission rate of up to 100 Mbps, supporting real-time data acquisition at a sampling rate of ≤1 kHz.

[0018] Preferably, the bottom shell is internally provided with a clamping groove, the clamping groove has a depth of 15mm, and a width with a matching gap of 0.1-0.2mm with the width of the air pump shell, the air pump is clamped and fixed with the bottom shell through the clamping groove, and the clamping groove is arranged at the middle of the left inner wall of the bottom shell.

[0019] Effective gain: compared with the prior art, the self-developed high-dimensional gas sensor array instrument of the application has the following beneficial effects:

[0020] 1. Wide detection range: can detect human-related volatile organic compounds, with a concentration range of 0.01-1000ppm, which can meet the detection needs in various scenes.

[0021] 2. High detection accuracy: detection lower limit ≤500ppb, which can capture low-concentration gas component changes and provide protection for accurate detection.

[0022] 3. Fast response speed: response / recovery time ≤30s, visual software response speed ≤0.5s, which can quickly feedback the detection results and improve the detection efficiency.

[0023] 4. Convenient operation: the modules work cooperatively, with high automation degree, and the visual software interface is intuitive, which is convenient for operators to use without the need for professional personnel to perform complex manual data processing.

[0024] 5. Comprehensive functions: for the first time, high-dimensional gas sensor array is combined with real-time visualization technology to realize an integrated solution from gas sampling, detection, signal processing, data transmission to result visualization, breaking through the limitation of single function of traditional gas detection equipment.

[0025] 6. Wide application: can be applied to target individual identification and feature characterization research based on gas fingerprint characteristics, early disease screening in medical diagnosis, individual tracking and identification in public safety field, quality detection in food industry and other fields, and has broad application prospect and important scientific value. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall appearance structure of the application.

[0027] Figure 2 It is a schematic diagram of the internal structure of the application.

[0028] Figure 3 It is a schematic diagram of the technical principle of the application.

[0029] Figure 4 It is a schematic diagram of the structure of the bottom shell in the application.

[0030] Figure 5 It is a schematic diagram of the structure of the top shell in the application.

[0031] Figure 6 The schematic diagram of the appearance structure of the vacuum pump in the application.

[0032] Figure 7 The schematic diagram of the structure of the 88-channel signal acquisition card in the application.

[0033] Figure 8 The schematic diagram of the internal structure of the test cavity in the application.

[0034] Figure 9 The design drawing of the test circuit board in the application. DETAILED DESCRIPTION

[0035] In order to make the above objectives, characteristics and advantages of the application more apparent, clear and easy to understand, the technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the application.

[0036] The embodiment discloses a self-researched high-dimensional gas sensor array instrument, and specific structures and assembly and connection modes thereof are as follows:

[0037] The bottom shell is a cuboid cavity structure, and a clamping groove is pre-set in the bottom shell and used for clamping and fixing the air pump. The upper surface of the bottom shell is further provided with a gasket, and four screw holes are pre-set on the gasket. During assembly, the lower surface of the test base is attached to the upper surface of the gasket, and the lower surface of the test circuit board is attached to the upper surface of the test base, and then four M4*20mm stainless steel screws are sequentially inserted into the screw holes of the test circuit board, the test base and the gasket and are screwed into the internal thread holes on the upper surface of the bottom shell, so that the test circuit board, the test base and the gasket are fixed to the bottom shell, and the gasket 2 can effectively buffer the vibration of the device during work, thereby ensuring the stability of the connection.

[0038] The assembly and gas flow structure of the test cavity, the bottom structure of the test cavity is integrally formed on the upper surface of the test circuit board, and the top structure of the test cavity is an independent cover plate member, and both are pre-set with 12 screw holes (hole diameter 3mm, hole positions are annularly distributed, the center of the circle coincides with the center of the test cavity, and the distance between adjacent holes is 25mm). During assembly, the top structure of the test cavity is covered on the bottom structure, so that the screw holes of the two are one-to-one corresponding, and then 12 M3*15mm screws are inserted into the corresponding screw holes and are screwed, so that the bottom and the top of the test cavity are sealingly connected, and a closed test cavity (cavity volume 20mL) is formed. The middle part of the left side wall of the test cavity is provided with an air inlet, and the middle part of the right side wall is provided with an air outlet (the specification is the same as that of the air inlet).

[0039] The data acquisition and transmission structure is connected between the test circuit board and the signal acquisition card through six data lines. The specific structure of the signal acquisition card is that the bottom is a blue silica gel plate, and six layers of data acquisition circuits are sequentially stacked on the upper surface of the substrate from bottom to top. An RJ45 data transmission network port is also provided on the bottom blue circuit board.

[0040] The specific position of the card slot 1 is set in the middle of the left inner wall of the bottom shell, and the card slot depth is designed to be 15 mm, and the width is matched with the width of the air pump shell (gap 0.1-0.2 mm), through the card slot, the air pump is quickly positioned and installed in the device, which can effectively avoid displacement caused by vibration during the operation of the air pump, and ensure the stability of the airflow.

[0041] The gasket is made of polytetrafluoroethylene material with a thickness of 3 mm, and the size is completely matched with the lower surface of the test base (error ≤0.5 mm), and four screw holes (hole diameter 4 mm, hole position rectangular distribution, horizontal spacing 80 mm, vertical spacing 60 mm) are pre-set on the gasket 2.

[0042] The inner diameters of the gas inlet and the gas outlet are both 8 mm, and the interface type is selected as a pagoda joint. The gas inlet is used to connect the external special gas (such as corrosive gas, inert gas, etc.), and the gas outlet is used to discharge the gas inside the cavity, forming a stable flow channel for the special gas in the test cavity, meeting the test requirements in different gas environments.

[0043] The substrate is made of silica gel plate (size 100 mm x 80 mm, thickness 2 mm), which has good mechanical strength. Six layers of data acquisition circuits are sequentially stacked on the upper surface of the substrate from bottom to top, and each layer of circuit has a thickness of 0.1 mm. The interlayer is interconnected by a via hole with a diameter of 0.2 mm (the inner wall of the via hole is plated with copper with a thickness of ≥20 μm), and each layer of circuit corresponds to 16 independent signal acquisition channels (total channel number 88), which can simultaneously acquire multiple test data.

[0044] The network port is set in the middle of the right edge of the substrate, and the network port is designed in a shielded manner (complying with IEC 60603-7 standard). A super five category network cable (according to an preferred embodiment, the network cable is selected as CAT5e type, and the transmission bandwidth is 100 MHz) is connected with the network port of the computer to realize high-speed data transmission between the signal acquisition card and the computer, and the transmission rate can reach 100 Mbps, meeting the real-time data acquisition requirements (sampling rate ≤1 kHz). The gas flow rate is controlled at 0.5-2 L / min by the flowmeter at the front end of the gas inlet, and the working power of the air pump is adjusted to 1-10 W.

[0045] The device workflow is as follows: after assembly, special gas is introduced from the gas inlet of the test cavity, contacts the test piece (placed in the test cavity, the part not described is a conventional design) inside the cavity, and is discharged from the gas outlet; the air pump is started to assist in adjusting the gas flow rate in the cavity; the test circuit board collects the electrical signals of the test piece in the special gas environment, and transmits the signals to the signal acquisition card through the data line; the six-layer acquisition circuit of the signal acquisition card amplifies and filters the signals, and then transmits the data to the computer through the network port of the bottom circuit board and the network cable. The following two examples are used to illustrate the application in detail:

[0046] Example 1

[0047] In Example 1, the self-developed high-dimensional gas sensor array instrument of the application is made. First, the raw materials and equipment required by each module are prepared, including a micro pump, a dustproof and moistureproof sampling head, a polytetrafluoroethylene pipeline, sensors based on different metal oxide semiconductors, a preamplifier, a filter, an analog-to-digital converter, a network cable, a computer, and related electronic components, mechanical structural components, etc.

[0048] Then, the following steps are followed:

[0049] Step 1: Assemble the gas sampling module: connect the micro pump, the dustproof and moistureproof sampling head, and the polytetrafluoroethylene pipeline to ensure tight connection and no gas leakage. Adjust the micro pump to make its sampling flow rate stable and adjustable within the range of 0.2L-3.0L / min.

[0050] Step 2: Build the high-dimensional gas sensor array module: select 80 sensors based on different metal oxide semiconductors and with different gas selectivity, arrange them according to the compact design, and fix them on the corresponding substrate to ensure that the positions of the sensors are reasonable and can fully contact with the gas.

[0051] Step 3: Build the signal processing module: connect the preamplifier, the filter, and the analog-to-digital converter according to the circuit design to ensure that the preamplifier can effectively amplify the weak signal, the filter can well remove the noise, and the analog-to-digital converter can accurately complete the signal conversion.

[0052] Step 4: Connect the modules: connect the gas sampling module and the high-dimensional gas sensor array module through the pipeline, connect the output end of the high-dimensional gas sensor array module and the input end of the signal processing module, and connect the signal processing module and the computer through the network cable.

[0053] Step 5: Install and debug the visualization software module: Install the self-developed visualization software on the computer, debug the software, ensure that it can normally receive data, support pre-selected channels, set data storage path and sampling frequency, etc., and can real-time analyze data, visualize the gas concentration change trend and related data characteristics, and the response speed is ≤0.5s.

[0054] Step 6: Overall debugging and performance testing: Power on the entire instrument for debugging, check if each module works normally. Test the detection accuracy, sensitivity, response time and other performance indicators of the instrument using standard gas samples, adjust and optimize according to the test results, and ensure that the instrument meets the design requirements and can stably and accurately detect gas.

[0055] Example 2:

[0056] This example is aimed at the mobile scenario of individual tracking and identification in the field of public security, optimizing the portability and anti-interference ability of the instrument, the steps are as follows:

[0057] Step 1: Use a micro diaphragm pump (weight ≤200g), the sampling flow can be adjusted to 2.5L / min (low power consumption mode), the endurance time is ≥4 hours (lithium battery power supply). The sampling head integrates an activated carbon pre-filter layer, which can filter common interference gases such as oil smoke and dust in the environment (filtration efficiency ≥95%).

[0058] Step 2: 80 sensors are arranged in an 8x10 matrix (overall size 10cmx5cmx2cm), a metal shielding shell is used to reduce electromagnetic interference (such as intercoms and monitoring equipment), and the sensor response / recovery time is optimized to ≤25s, suitable for fast mobile sampling requirements.

[0059] Step 3: Add a wireless transmission module (supporting 4G / 5G) based on network transmission, the transmission rate remains ≥100Mbps, which can upload data to the backend server in real time, while locally caching data (storage capacity ≥1000 groups), avoiding data loss caused by signal interruption.

[0060] Step 4: The software adds a "mobile tracking mode", which supports the display of GPS positioning information and gas fingerprint feature data correlation, generates a trajectory map of individual gas fingerprints changing with time and location, and can quickly compare the historical gas fingerprint library of the target individual (comparison time ≤1s).

[0061] The above shows and describes the basic principles and main features of the present application and the advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A self-developed high-dimensional gas sensor array instrument, characterized in that, The device comprises a bottom shell, a top shell, a suction pump, an array test module, and an 88-channel signal acquisition card, wherein the bottom shell is provided with fixed limiting screw columns, polytetrafluoroethylene gaskets, connecting sockets, network cable openings, power cable openings, and air inlet and outlet openings; the top shell is provided with connecting sockets and fixed limiting nut columns; the array test module comprises a test cavity, a test circuit board, a fixed base, a multi-channel numerical control power supply, a gas sampling module, a high-dimensional gas sensor array module, a signal processing module, a data transmission module, and a visualization software module; through the cooperative work of the modules, high-sensitivity, high-selectivity, multi-dimensional real-time detection and analysis of human-related volatile organic compounds are realized, and the detection results can be intuitively presented.

2. The self-developed high-dimensional gas sensor array instrument according to claim 1, characterized in that, The gas sampling module is connected to the high-dimensional gas sensor array module through a pipeline, the output end of the high-dimensional gas sensor array module is connected to the input end of the signal processing module, the signal processing module communicates with a computer installed with the visualization software module through the data transmission module; the gas sampling module adopts a micro-pump suction sampling mode, the sampling flow can be adjusted within the range of 0.2L-3.0L / min, the sampling head has dustproof and moisture-proof functions, and the sampling pipeline is made of polytetrafluoroethylene; the high-dimensional gas sensor array module is composed of more than 80 sensors based on different metal oxide semiconductors and having different gas selectivity, and adopts compact arrangement; the signal processing module comprises a preamplifier, a filter, and an analog-to-digital converter; the data transmission module adopts network transmission, and the transmission rate is greater than or equal to 100Mbps; The visualization software module can realize real-time analysis and visual presentation of the detection data, and the response speed is less than or equal to 0.5s.

3. The self-developed high-dimensional gas sensor array instrument according to claim 1, characterized in that, The suction pump adopts a brushless micro suction pump, and the brushless micro suction pump controls the gas flow rate to be 0.2-2000sccm.

4. The self-developed high-dimensional gas sensor array instrument according to claim 1, characterized in that, The 88-channel signal acquisition card is constructed by AD7606, AD7616, and STM32, multi-channel sensor signals are synchronously collected, data transmission is performed through a network port, the test cavity is made of polytetrafluoroethylene, the test cavity comprises a bottom structure and a top cover plate structure, the bottom structure is integrally formed with the upper surface of the test circuit board, the bottom structure and the top cover plate structure are both provided with 12 screw holes with a diameter of 3mm, the screw holes are annularly distributed and the centers of the screw holes coincide with the center of the test cavity, the distance between adjacent screw holes is 25mm, the bottom structure and the top cover plate structure are sealingly connected through 12 M3*15mm screws, the volume of the test cavity after sealing is 20mL, the middle part of the left side wall of the test cavity is provided with an air inlet, and the middle part of the right side wall is provided with an air outlet, the inner diameters of the air inlet and the air outlet are both 8mm, and the types of the interfaces are both pagoda joints, a flowmeter is arranged at the front end of the air inlet, and the flowmeter controls the gas flow rate to be 0.2-3L / min; the working power of the suction pump is adjusted to 1-10W.

5. The self-developed high-dimensional gas sensor array instrument according to claim 1, characterized in that, The multi-channel numerical control power supply uses the microprocessor STM32F103ZET6 newly launched by ST Company as the main control chip, the power supply voltage is 2V-3.6V, the 32-bit high-performance ARM Cortex-M3 RISC core is used, it has rich enhanced I / O ports and peripherals connected to two APB buses, supports serial single-wire debugging (SWD) and JTAG interface debugging, and JTAG can directly obtain debugging information from the CPU.

6. The self-developed high-dimensional gas sensor array instrument according to claim 1, characterized in that, The gas sampling module uses a miniature pump suction sampling method, the sampling flow can be adjusted in the range of 0.2L-3.0L / min, which can be flexibly adjusted according to different detection requirements, the sampling head is designed to have dustproof and moisture-proof function, which can effectively avoid the pollution of dust and moisture in the external environment to the collected gas sample, ensure the authenticity and accuracy of the sample, the sampling pipeline is made of polytetrafluoroethylene, which has stable chemical properties and can reduce the adsorption and loss of gas during transmission, ensuring the integrity of the gas sample.

7. The self-developed high-dimensional gas sensor array instrument according to claim 1, characterized in that, The high-dimensional gas sensor array module selects sensors based on different metal oxide semiconductors, forming an 80-sensor array, each sensor has different gas selectivity and can produce specific response to different types of gas components, thereby realizing detection of multiple volatile organic compounds, the sensor array is designed in a compact manner, which reduces the size of the device while ensuring that the gas is in full contact with each sensor, improving the accuracy of detection, this module can detect human-related volatile organic compounds with a concentration range of 0.02-1000ppm, a detection lower limit of ≤500ppb, and a response / recovery time of ≤30s.

8. The self-developed high-dimensional gas sensor array instrument according to claim 1, characterized in that, The signal processing module includes a preamplifier, a filter and an analog-to-digital converter, the preamplifier can amplify the weak electrical signal output by the sensor to a range that can be recognized by the analog-to-digital converter for subsequent processing, the filter can remove environmental noise and sensor noise to ensure signal purity, and the analog-to-digital converter accurately converts analog electrical signals into digital signals through sampling, quantization and coding, laying a foundation for data transmission and analysis.

9. The self-developed high-dimensional gas sensor array instrument according to claim 1, characterized in that, The data transmission module uses a network cable for data transmission, the transmission rate is ≥100Mbps, which can meet the real-time transmission requirements of gas sensitive detection data and ensure the timeliness of the detection results.

10. The self-developed high-dimensional gas sensor array instrument according to claim 1, characterized in that, The visualization software module is self-developed and can perform real-time analysis and visualization of the digital signals obtained during gas sensitive detection, the software supports pre-selection of channels, setting of data storage paths and sampling frequencies, can intuitively display the gas concentration change trend and related data characteristics, and is convenient for operators to quickly master the detection dynamics and make analysis and judgment, and the response speed is ≤0.5s.

11. The self-developed high-dimensional gas sensor array instrument according to claim 1, characterized in that, The test circuit board is connected with the 88-channel signal acquisition card through six data lines, the data lines are used for transmitting test control signals and test data, the substrate of the 88-channel signal acquisition card is a silica gel plate, the size of the silica gel plate is 100mm*80mm, and the thickness is 2mm; six layers of circuit for collecting data are sequentially stacked on the upper surface of the silica gel plate from bottom to top, the thickness of each layer of circuit is 0.1mm, the interlayer is interconnected through a via hole with a diameter of 0.2mm, the inner wall of the via hole is plated with copper with a thickness of greater than or equal to 20μm, each layer of circuit corresponds to 16 independent signal acquisition channels, and the total number of channels is 88; the silica gel plate of the 88-channel signal acquisition card is provided with an RJ45 data transmission network port, the network port is arranged at the right edge of the silica gel plate in the middle and adopts a shielded design in line with the IEC 60603-7 standard, the network port is connected with a computer through a CAT5e class ultra five-class network cable, the data transmission rate can reach 100Mbps, and real-time data acquisition with a sampling rate of less than or equal to 1kHz is supported.

12. The self-developed high-dimensional gas sensor array instrument according to claim 1, characterized in that, The bottom shell is internally provided with a preset clamping groove, the depth of the clamping groove is 15mm, the width of the clamping groove is matched with the width of the air pump shell with a gap of 0.1-0.2mm, the air pump is clamped and fixed with the bottom shell through the clamping groove, and the clamping groove is arranged at the left middle of the inner wall of the bottom shell.

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