Electronic nose gas analysis system based on Internet of Things technology

Abstract

The invention relates to the technical field of gas detection equipment, and discloses an electronic nose gas analysis system based on the Internet of Things technology, which comprises an acquisition module, a gas path transmission module, a gas reaction module, a computer and a power supply module, the acquisition module is used for acquiring a gas sample from an external environment; the gas path transmission module is used for conveying gas from the sampling module to the gas analysis module; the gas reaction module is used for enabling target gas and a specific reaction reagent to be in contact with each other for reaction, and the gas reaction module comprises a plurality of groups of sensor arrays; the computer preprocesses the electric signals output by the sensor array and analyzes and processes the preprocessed data; the power supply module is used for providing electric energy for each power consumption component in the system; the device is simple in structure, convenient to use, high in detection precision and good in user experience.

Description

Technical Field

[0001] The present invention relates to the technical field of gas detection equipment, and in particular to an electronic nose gas analysis system based on Internet of Things technology. Background Art

[0002] An electronic nose is an instrument that simulates the biological olfactory system. It mainly consists of a gas sensor array, a signal processing unit, and a pattern recognition algorithm. The gas sensor array is the core part of the electronic nose, which can respond to different gas components. Early gas sensors were mainly based on chemical sensors, such as metal oxide semiconductor (MOS) sensors. This sensor is sensitive to a variety of gases, and its working principle is that when gas molecules are adsorbed on the surface of the sensor, it causes a change in the resistance of the sensor. For example, when detecting carbon monoxide in the air, carbon monoxide molecules are adsorbed on the surface of the MOS sensor, causing the electrical properties of the sensor to change, thereby generating a detectable signal. With the development of technology, other types of gas sensors have emerged, such as electrochemical sensors, optical sensors, etc.

[0003] With the advancement of science and technology, people have discovered that smell can also be used as a criterion for measuring product quality. For example, if food or grain deteriorates or becomes moldy, the corresponding gas will evaporate. Sometimes people can smell it, but sometimes it is difficult to detect. Therefore, the electronic nose that simulates olfactory detection came into being. Electronic nose technology has the advantages of real-time, rapid, and non-destructive testing. However, there is currently a lack of universal electronic nose detection equipment, and the existing detection system is not fully functional and has low detection accuracy.

[0004] Therefore, there is an urgent need for a technology to replace the existing detection system to solve the problems of incomplete detection system functions and low detection accuracy. Summary of the invention

[0005] The embodiment of the present application provides an electronic nose gas analysis system based on Internet of Things technology, which is used to solve the problems existing in the related art, such as incomplete detection system functions and low detection accuracy.

[0006] According to one aspect of the embodiments of the present application, an electronic nose gas analysis system based on Internet of Things technology is provided, comprising:

[0007] Acquisition module, gas transmission module, gas reaction module, control module, data processing module and power supply module;

[0008] The acquisition module is used to obtain gas samples from the external environment, and the acquisition module includes a baseline adjustment channel and a sampling channel, and the baseline adjustment channel and the sampling channel are connected to the enrichment channel;

[0009] The gas transmission module is used to transport the gas from the sampling module to the gas reaction module, and the gas transmission module includes a magnetic valve group, a vacuum pump group and a flow meter group;

[0010] The gas reaction module is used to contact and react the target gas and a specific reaction reagent. The gas reaction module establishes multiple reaction zones, each zone is for a specific gas component, and each zone uses a different reaction reagent and sensor array to react various components in the collected mixed gas in different zones at the same time;

[0011] The control module is used to control the workflow of the entire system and adjust the parameters of the sensor according to the characteristics of the target gas;

[0012] The data processing module is used to amplify, filter, reduce noise and normalize the weak electrical signals output by the sensor array, perform digital conversion on the pre-processed signals, use the built-in algorithm to analyze and process the data, and transmit the processed data in real time to the remote monitoring center and mobile terminal through the wireless communication module with the help of the Internet of Things technology;

[0013] The power supply module is used to provide electric energy to various power-consuming components in the system.

[0014] Furthermore, the enrichment channel is used to gather and concentrate the target gas molecules, and use the adsorbent to adsorb the target gas. When a certain amount of gas is adsorbed on the surface of the adsorption material in the channel, it is quickly released to the vicinity of the sensor array through a desorption process.

[0015] Furthermore, before detecting the target gas, the gas reaction module first adjusts the electronic flowmeter to the initial value, then connects the standard gas for adjusting the baseline, and then powers on the second solenoid valve to connect the normally closed channel; powers on the third solenoid valve to connect the normally closed channel; powers on the fifth solenoid valve to change from normally closed to open; the first vacuum pump powers on and starts working to draw the standard gas through the electronic flowmeter and the fifth solenoid valve, and enters different reaction zones through the gas path; at the same time, the sixth solenoid valve, the seventh solenoid valve and the eighth solenoid valve are respectively powered on to connect the electrical paths, and the second vacuum pump starts to power on to slowly discharge the gas in the reaction zone through the manual regulating valve at a speed first fast and then slow. In this process, the changes in the values ​​collected by the sensors of the three gas chambers are observed. When the baseline adjustment is stable, the sensor baseline can be calibrated.

[0016] Furthermore, after calibrating the sensor baseline, the first solenoid valve, the second solenoid valve, the third solenoid valve and the fifth solenoid valve are powered off, the first vacuum pump is powered off, and the baseline adjustment channel stops supplying gas; the flow control of the manual flowmeter is adjusted, and the second vacuum pump continues to work to slowly extract the standard gas in the reaction area, reduce the concentration of the standard gas in the gas chamber, and reduce the air pressure for the target gas to enter the gas chamber; after the concentration of the gas chamber is reduced, the sampling channel begins to take in air, the first solenoid valve, the second solenoid valve, and the third solenoid valve are powered on respectively, the fifth solenoid valve is turned on, and the first vacuum pump is started. Due to the pressure difference, the sampling gas quickly enters the gas chamber and diffuses. When the sampling gas basically fills the gas chamber, the sixth solenoid valve, the seventh solenoid valve and the eighth solenoid valve are turned on respectively, the second vacuum pump is powered on, and the manual flowmeter is adjusted to overflow part of the target gas and the original standard gas in the gas chamber. At this time, the fourth solenoid valve is turned on to discharge the gas. After the target gas fills the gas chamber, all solenoid valves and pumps are powered off, and the sensor analyzes and reads stable readings of the gas.

[0017] Furthermore, the collection module also includes an extraction device, which transports the gas to the enrichment channel to provide a continuous supply of original gas samples for the enrichment process. The air inlet of the collection module is used for preliminary filtering and purification of the air.

[0018] Furthermore, the gas reaction module includes a built-in heating device, which is used to increase the temperature of the reaction system to a suitable range and activate the activity of the reagents.

[0019] Furthermore, the control module is also used for the rational allocation of system resources, including the allocation of power and computing resources; when there are multiple gas sensors working simultaneously in the system, it can rationally allocate power according to the focus of the detection task and the priority of the sensor to ensure that key sensors have sufficient power to maintain a high-precision working state.

[0020] Furthermore, the electrical signal normalization operation is to convert data of different dimensions and ranges into a unified standard range. The normalization method is maximum-minimum normalization, and its formula is:

[0021]

[0022] Among them, x is the original data;

[0023] x max and x min are the minimum and maximum values ​​in the original data respectively;

[0024] x nex is the new data after normalization.

[0025] Furthermore, the power supply module is also used to monitor and protect the power supply. The power supply module monitors the specific parameters of the output voltage and current of the power supply in real time, and can cut off the power supply output in time when an abnormal situation occurs in the power supply.

[0026] Furthermore, the electronic nose gas analysis system also includes a data storage module for storing detected gas data and information on system operating parameters; the data storage module can adopt a combination of local storage and cloud storage to ensure data security and accessibility.

[0027] Compared with the prior art, the present invention has the following advantages:

[0028] (1) Establishing multiple reaction zones and using different reaction reagents and sensor arrays for specific gas components can allow various components in the collected mixed gas to react simultaneously in different zones, greatly improving the detection efficiency. It can also realize one-time analysis and detection of multiple components in complex mixed gases, enhancing the detection capability and accuracy of the entire system for different gas components;

[0029] (2) The weak electrical signals output by the sensor array are amplified, filtered, noise-reduced, and normalized, effectively improving the signal quality. After digital conversion, the built-in algorithm is used for analysis and processing, making the data more valuable for reference. And with the help of Internet of Things technology, the processed data can be transmitted to the remote monitoring center and mobile terminal in real time through the wireless communication module, making it convenient for staff to remotely grasp the detection situation in real time and make decisions and countermeasures in a timely manner.

[0030] The technical solution of the present application is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings, which constitute a part of the specification, illustrate embodiments of the present application and, together with the description, serve to explain the principles of the present application.

[0032] The present application can be more clearly understood from the following detailed description with reference to the accompanying drawings, in which:

[0033] Figure 1 The structure block diagram of the electronic nose gas analysis system based on Internet of Things technology provided by one embodiment of the present application is shown;

[0034] Figure 2 A system circuit diagram of an electronic nose gas analysis system based on Internet of Things technology provided by an embodiment of the present application is shown; DETAILED DESCRIPTION

[0035] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0036] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

[0037] The following description of at least one exemplary embodiment is merely illustrative in nature and is not intended to limit the present application, its application, or uses.

[0038] Technologies, systems, and devices known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, systems, and devices should be considered part of the specification.

[0039] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0040] In addition, the technical solutions between the various embodiments of the present application can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0041] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0042] Combine the following Figure 1-Figure 2 To describe the electronic nose gas analysis system based on the Internet of Things technology according to the exemplary embodiment of the present application. It should be noted that the following application scenarios are only shown to facilitate understanding of the spirit and principles of the present application, and the embodiments of the present application are not limited in this regard. On the contrary, the embodiments of the present application can be applied to any applicable scenario.

[0043] Furthermore, the present application proposes an electronic nose gas analysis system based on Internet of Things technology.

[0044] Acquisition module, gas transmission module, gas reaction module, control module, data processing module and power supply module;

[0045] The acquisition module is used to obtain gas samples from the external environment. The acquisition module includes a baseline adjustment channel and a sampling channel. The baseline adjustment channel and the sampling channel are connected to the enrichment channel.

[0046] The gas transmission module is used to transport the gas from the sampling module to the gas reaction module, and the gas transmission module includes a magnetic valve group, a vacuum pump group and a flow meter group;

[0047] The gas reaction module is used to contact and react the target gas and specific reaction reagents. The gas reaction module establishes multiple reaction zones, each zone is for a specific gas component, and each zone uses different reaction reagents and sensor arrays to react various components in the collected mixed gas in different zones at the same time;

[0048] Further, the composition of the sensor array and the classification in the air chamber are:

[0049] (1) First reaction zone: carbon dioxide and oxygen detection array

[0050] Target gases: Carbon dioxide (CO2) and oxygen (O2)

[0051] Sensor used: ①Sensor 1 (oxygen sensor, specifically used for oxygen detection)

[0052] ②Sensor 2 (carbon dioxide sensor, suitable for carbon dioxide concentration detection)

[0053] Since oxygen sensors need to be protected from oxidation, infrared sensors for detecting carbon dioxide are specially designed to be placed in an air chamber to avoid cross-influence.

[0054] (2) Second reaction zone: Alkane and reducing gas detection array

[0055] Target gas: Alkane gases such as methane, propane, butane, and reducing gases such as hydrogen and carbon monoxide

[0056] Use sensors:

[0057] ①Sensor 1 is used to detect propane, butane and liquefied gas.

[0058] ②Sensor 2 specifically detects methane (CH4).

[0059] ③Sensor 3 detects various alkane gases such as methane, propane, isobutane, etc.

[0060] ④Sensor 4 is used to detect alkane gases such as methane and butane

[0061] ⑤Sensor 5 can detect liquefied gas and methane

[0062] ⑥ Sensor 6 is used as a supplementary sensor for alkanes and reducing gases to detect hydrogen, carbon monoxide and combustible gases.

[0063] (3) Third reaction zone: Volatile organic compounds (VOC) and other gas detection array Target gases: ethanol, amines, hydrogen sulfide, aldehydes, lipids, ketones and other volatile organic compounds (VOC)

[0064] Use sensors:

[0065] ①Sensor 1 is used to detect organic volatile gases such as ethanol, lipids, alcohols, etc.

[0066] ②Sensor 2 detects hydrogen sulfide (H2S), amine compounds, and volatile organic compounds.

[0067] ③ Sensor 3 is used to detect amines and sulfides (such as gases from food corruption).

[0068] ④Sensor 4 is used to detect hydrogen sulfide (H2S). (MQ136)

[0069] ⑤Sensor 5 supplements the detection of ethanol.

[0070] ⑥ Sensor 6 additionally detects ammonia, hydrogen sulfide and other volatile organic compounds in the air.

[0071] ⑦Sensor 7 is used to detect organic solvent gases such as aldehydes and ketones;

[0072] ⑧Sensor 8 is mainly used to detect formaldehyde, and can also detect benzene, acetic acid, acetone, etc.

[0073] The control module is used to control the workflow of the entire system and adjust the parameters of the sensor according to the characteristics of the target gas;

[0074] The data processing module is used to amplify, filter, reduce noise and normalize the weak electrical signals output by the sensor array, digitize the pre-processed signals, analyze and process the data using built-in algorithms, and transmit the processed data in real time to the remote monitoring center and mobile terminal through the wireless communication module with the help of Internet of Things technology;

[0075] The power module is used to provide electrical energy to various power-consuming components in the system.

[0076] Specifically, multiple reaction zones are established, and each zone is designed for specific gas components. For example, the first reaction zone focuses on carbon dioxide and oxygen, the second reaction zone targets alkanes and reducing gases, and the third reaction zone focuses on volatile organic compounds and other gases. This enables classified processing of different types of gases, which helps to improve the targetedness and professionalism of detection.

[0077] It is understandable that the use of different reaction reagents and carefully configured sensor arrays in different areas allows the multiple components in the collected mixed gas to react and detect simultaneously in different areas. For example, the first reaction area uses special sensors for carbon dioxide and oxygen to avoid cross-influence and improve detection accuracy; the second reaction area uses multiple sensors to detect alkanes and reducing gases from different angles, which can more comprehensively grasp the situation of such gases; the third reaction area uses multiple sensors to detect a wide variety of volatile organic compounds and related gases, covering all types of organic volatiles that may appear to the greatest extent, etc., which greatly improves the efficiency and accuracy of detecting complex mixed gas components.

[0078] Specifically, the enrichment channel is used to gather and concentrate the target gas molecules and use the adsorbent to adsorb the target gas. When a certain amount of gas is adsorbed on the surface of the adsorption material in the channel, it is quickly released to the vicinity of the sensor array through the desorption process.

[0079] Specifically, the enrichment channel can be designed with a selective filtering mechanism to remove some interfering gases that are not related to the target gas detection through physical barriers, chemical reactions or selective adsorption. For example, when detecting trace amounts of harmful volatile organic compounds (VOCs) in the air, the filter material in the enrichment channel can pre-remove a large amount of background gases such as water vapor, nitrogen, and oxygen, so that the target VOCs gas mainly enters the sensor array, thereby improving the accuracy and selectivity of the detection and reducing the possibility of misjudgment.

[0080] Specifically, before detecting the target gas, the gas reaction module first adjusts the electronic flowmeter to the initial value, then connects the standard gas for adjusting the baseline, and then powers on the second solenoid valve to connect the normally closed channel; the third solenoid valve powers on to connect the normally closed channel; the fifth solenoid valve powers on to change from normally closed to open; the first vacuum pump powers on and starts working to draw the standard gas through the electronic flowmeter and the fifth solenoid valve, and into different reaction zones through the gas path; at the same time, the sixth solenoid valve, the seventh solenoid valve and the eighth solenoid valve are respectively powered on to connect the electrical paths, and the second vacuum pump starts to power on to slowly discharge the gas in the reaction zone through the manual regulating valve at a speed first fast and then slow. In this process, the changes in the values ​​collected by the sensors of the three gas chambers are observed. When the baseline adjustment is stable, the sensor baseline can be calibrated.

[0081] Specifically, after calibrating the sensor baseline, the first solenoid valve, the second solenoid valve, the third solenoid valve and the fifth solenoid valve are powered off, the first vacuum pump is powered off, and the baseline adjustment channel stops supplying gas; the flow control of the manual flowmeter is adjusted, and the second vacuum pump continues to work to slowly extract the standard gas in the reaction area, reduce the concentration of the standard gas in the gas chamber, and reduce the air pressure for the target gas to enter the gas chamber; after the concentration of the gas chamber is reduced, the sampling channel begins to take in air, the first solenoid valve, the second solenoid valve, and the third solenoid valve are powered on respectively, the fifth solenoid valve is turned on, and the first vacuum pump is started. Due to the pressure difference, the sampling gas quickly enters the gas chamber and diffuses. When the sampling gas basically fills the gas chamber, the sixth solenoid valve, the seventh solenoid valve and the eighth solenoid valve are turned on respectively, the second vacuum pump is powered on, and the manual flowmeter is adjusted to overflow part of the target gas and the original standard gas in the gas chamber. At this time, the fourth solenoid valve is turned on to discharge the gas. After the target gas fills the gas chamber, all solenoid valves and pumps are powered off, and the sensor analyzes and reads stable gas readings.

[0082] It is understandable that by adjusting the electronic flow meter to the initial value and introducing the standard gas for adjusting the baseline, an accurate reference point can be established for subsequent detection. In gas detection, the output signal of the sensor may be affected by various factors and drift. Introducing standard gas for baseline adjustment can effectively eliminate this drift and ensure the accuracy of the test results. For example, in long-term environmental monitoring, the sensor may gradually deviate from its initial state due to changes in environmental temperature, humidity and other factors. By regularly adjusting the baseline, the sensor can always be kept in an accurate working state.

[0083] Furthermore, the coordinated work of multiple solenoid valves and vacuum pumps ensures that the standard gas can accurately enter different reaction zones. This precise control can ensure that each reaction zone can obtain the same standard gas concentration, thereby providing a unified standard for subsequent sensor calibration. For example, in a system that simultaneously detects multiple gas components, different reaction zones may have different sensitivities to different gases. Calibration with a unified standard gas can make the detection results of different reaction zones comparable.

[0084] Specifically, the collection module also includes an extraction device, which transports the gas to the enrichment channel to provide a steady supply of original gas samples for the enrichment process. The air inlet of the collection module is used for preliminary filtration and purification of the air.

[0085] It is understandable that the stable operation of the extraction device can reduce the uncertainty factors in the gas collection process. Compared with the passive gas collection method, the extraction device can provide a more stable gas flow and pressure, making the operation of the entire system more reliable.

[0086] Specifically, the gas reaction module includes a built-in heating device, which is used to increase the temperature of the reaction system to a suitable range and activate the activity of the reagents.

[0087] It is understandable that appropriately increasing the temperature can make the reaction proceed more rapidly. Generally speaking, the reaction rate may be slow at room temperature, but when the heating device raises the reaction temperature to 300-500°C (the specific temperature depends on the catalyst and other conditions), the reaction rate will be greatly accelerated, which helps to complete the detection process in a short time.

[0088] Specifically, the control module is also used for the rational allocation of system resources, including the allocation of power and computing resources. When there are multiple gas sensors working simultaneously in the system, it can rationally allocate power according to the focus of the detection task and the priority of the sensor to ensure that key sensors have sufficient power to maintain a high-precision working state.

[0089] Specifically, the normalization operation of electrical signals is to convert data of different dimensions and ranges into a unified standard range. The normalization method is maximum-minimum normalization, and its formula is:

[0090]

[0091] Among them, x is the original data;

[0092] x max and x min are the minimum and maximum values ​​in the original data respectively;

[0093] x nex is the new data after normalization.

[0094] Specifically, the power module is also used to monitor and protect the power supply. The power module monitors the specific parameters of the output voltage and current of the power supply in real time. When the power supply is abnormal, it can cut off the power output in time.

[0095] It is understandable that by real-time monitoring of the output voltage and current parameters of the power supply, abnormal power supply conditions such as overvoltage, overcurrent, etc. can be discovered in a timely manner. When these abnormal conditions occur, quickly cutting off the power output can effectively prevent damage to various power-consuming components in the system due to excessive voltage or current.

[0096] Specifically, the electronic nose gas analysis system also includes a data storage module for storing detected gas data and information on system operating parameters; the data storage module can use a combination of local storage and cloud storage to ensure data security and accessibility.

[0097] Understandably, the dual protection of local storage and cloud storage greatly reduces the risk of data loss. If you rely solely on local storage, data may be lost once the device fails, is damaged, or is stolen. With cloud storage as a backup, even if there is a problem with the local device, the data can still be safely stored in the cloud. For example, in an industrial environment, if the device where the electronic nose gas analysis system is located is damaged due to an accident, the data stored in the cloud can be quickly restored to ensure the continuity and integrity of the gas monitoring data.

[0098] It should be noted that:

[0099] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known structures and technologies are not shown in detail so as not to obscure the understanding of this description.

[0100] Similarly, it should be understood that in order to streamline the present application and aid in understanding one or more of the various inventive aspects, in the above description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the disclosed system should not be interpreted as reflecting the following schematic diagram: the claimed application requires more features than those explicitly recited in each claim.

[0101] Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment.The claims following the Detailed Description are thus hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of this application.

[0102] Furthermore, those skilled in the art will appreciate that although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features from different embodiments is meant to be within the scope of the present application and to form different embodiments.

[0103] For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0104] The above is only a preferred specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. An electronic nose gas analysis system based on Internet of Things technology, characterized in that: include: Acquisition module, gas transmission module, gas reaction module, control module, data processing module and power supply module; The collection module is used to obtain gas samples from the external environment; The gas transmission module is used to transport the gas from the collection module to the gas reaction module, and the gas transmission module includes a magnetic valve group, a vacuum pump group and a flow meter group; The gas reaction module is used to contact and react the target gas and a specific reaction reagent. The gas reaction module establishes multiple reaction zones, each zone is for a specific gas component, and each zone uses a different reaction reagent and sensor array to react various components in the collected mixed gas in different zones at the same time; The control module is used to control the workflow of the entire system and adjust the parameters of the sensor according to the characteristics of the target gas; The data processing module is used to amplify, filter, reduce noise and normalize the weak electrical signals output by the sensor array, perform digital conversion on the pre-processed signals, use the built-in algorithm to analyze and process the data, and transmit the processed data in real time to the remote monitoring center and mobile terminal through the wireless communication module with the help of the Internet of Things technology; The power supply module is used to provide electric energy to various power-consuming components in the system.

2. The electronic nose gas analysis system of the Internet of Things technology according to claim 1 is characterized in that: The acquisition module includes a baseline adjustment channel, a sampling channel and an enrichment channel. The enrichment channel is used to gather and concentrate the target gas molecules and adsorb the target gas using an adsorbent. When a certain amount of gas is adsorbed on the surface of the adsorption material in the channel, it is quickly released to the vicinity of the sensor array through a desorption process.

3. The electronic nose gas analysis system of the Internet of Things technology according to claim 2 is characterized in that: Before detecting the target gas, the gas reaction module first adjusts the electronic flowmeter to the initial value, then connects the standard gas for adjusting the baseline, and then powers on the second solenoid valve to connect the normally closed channel; powers on the third solenoid valve to connect the normally closed channel; powers on the fifth solenoid valve to change from normally closed to open; powers on the first vacuum pump to start working, draws the standard gas through the electronic flowmeter and the fifth solenoid valve, and enters different reaction zones through the gas path; at the same time, the sixth solenoid valve, the seventh solenoid valve and the eighth solenoid valve are respectively powered on to connect the electrical paths, and the second vacuum pump starts to power on to slowly discharge the gas in the reaction zone through the manual regulating valve at a speed first fast and then slow. In this process, the changes in the values ​​collected by the sensors of the three gas chambers are observed. When the baseline adjustment is stable, the sensor baseline can be calibrated at this time.

4. The electronic nose gas analysis system of the Internet of Things technology according to claim 3 is characterized in that: After calibrating the sensor baseline, the first solenoid valve, the second solenoid valve, the third solenoid valve and the fifth solenoid valve are powered off, the first vacuum pump is powered off, and the baseline adjustment channel stops supplying gas; the flow control of the manual flowmeter is adjusted, and the second vacuum pump continues to work to slowly extract the standard gas in the reaction area, reduce the concentration of the standard gas in the gas chamber, and reduce the air pressure for the target gas to enter the gas chamber; after the concentration of the gas chamber is reduced, the sampling channel begins to take in air, the first solenoid valve, the second solenoid valve, and the third solenoid valve are powered on respectively, the fifth solenoid valve is turned on, and the first vacuum pump is started. Due to the pressure difference, the sampling gas quickly enters the gas chamber and diffuses. When the sampling gas basically fills the gas chamber, the sixth solenoid valve, the seventh solenoid valve and the eighth solenoid valve are turned on respectively, the second vacuum pump is powered on, and the manual flowmeter is adjusted to overflow part of the target gas and the original standard gas in the gas chamber. At this time, the fourth solenoid valve is turned on to discharge the gas. After the target gas fills the gas chamber, all solenoid valves and pumps are powered off, and the sensor analyzes and reads stable gas readings.

5. The electronic nose gas analysis system of the Internet of Things technology according to claim 1 is characterized in that: The collection module also includes an extraction device, which transports the gas to the enrichment channel to provide a continuous supply of original gas samples for the enrichment process. The air inlet of the collection module is used for preliminary filtering and purification of the air.

6. The electronic nose gas analysis system of the Internet of Things technology according to claim 1 is characterized in that: The gas reaction module includes a built-in heating device, which is used to increase the temperature of the reaction system to a suitable range and activate the activity of the reagents.

7. The electronic nose gas analysis system of the Internet of Things technology according to claim 1 is characterized in that: The control module is also used for the rational allocation of system resources, including the allocation of power and computing resources. When multiple gas sensors are working simultaneously in the system, it can rationally allocate power according to the focus of the detection task and the priority of the sensor to ensure that key sensors have sufficient power to maintain a high-precision working state.

8. The electronic nose gas analysis system of the Internet of Things technology according to claim 1 is characterized in that: The electrical signal normalization operation is to convert data of different dimensions and ranges into a unified standard range. The normalization method is maximum-minimum normalization, and its formula is: Among them, x is the original data; x max and x min are the minimum and maximum values ​​in the original data respectively; x nex is the new data after normalization.

9. The electronic nose gas analysis system of the Internet of Things technology according to claim 1 is characterized in that: The power supply module is also used to monitor and protect the power supply. The power supply module monitors the specific parameters of the output voltage and current of the power supply in real time, and can cut off the power supply output in time when an abnormal situation occurs in the power supply.

10. The electronic nose gas analysis system of the Internet of Things technology according to claim 1 is characterized in that: The electronic nose gas analysis system also includes a data storage module for storing detected gas data and information on system operating parameters; the data storage module can use a combination of local storage and cloud storage to ensure data security and accessibility.

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