Gas recognition device, gas recognition method and electronic nose system

Abstract

The invention relates to the technical field of gas detection, in particular to a gas recognition device, a gas recognition method and an electronic nose system.The gas recognition device comprises a constant-temperature gas circuit unit, a sensor array, a calibration unit and a data processing unit; the constant-temperature gas circuit unit is used for receiving to-be-tested gas and providing a temperature-controllable testing environment for the to-be-tested gas; the sensor array is used for acquiring information of to-be-detected gas and converting the information into an electric signal; the calibration unit is connected with the data processing unit and is used for generating a reference signal, transmitting the reference signal to the data processing unit and providing a calibration reference for the electric signal of the sensor array; the data processing unit is connected with the constant-temperature gas circuit unit and is also connected with the sensor array; and the data processing unit is used for controlling the formation and switching of the test environment, receiving the electric signal and identifying the information of the gas to be tested.

Description

Technical Field

[0001] This disclosure relates to the field of gas detection technology, and in particular to a gas identification device, a gas identification method, and an electronic nose system. Background Technology

[0002] With the rapid development of the Internet of Things, intelligent detection, and health monitoring, odor recognition technology is showing significant application prospects in food freshness assessment, non-invasive medical diagnosis, environmental pollutant monitoring, and industrial process control. Traditional odor recognition relies on human sensory evaluation or large analytical instruments, which suffers from problems such as high subjectivity, complex operation, and difficulty in real-time online detection.

[0003] Gas sensor array technology is currently one of the mainstream methods for odor recognition. It uses an array of multiple gas sensors with cross-sensitivity, combined with pattern recognition algorithms, to identify and classify complex odor components. Currently, widely used sensor arrays are mainly based on traditional gas-sensitive materials such as metal-oxide-semiconductor (MOS) semiconductors. This technology achieves a certain degree of rapid response and preliminary odor identification. In recent years, the introduction of microelectromechanical systems (MEMS) technology has driven the miniaturization and low-power consumption of gas sensors.

[0004] However, existing sensors suffer from poor selectivity, slow response speed, unsatisfactory size and integration, and serious lack of performance consistency between different batches. As a result, the recognition models constructed have low versatility and are difficult to apply stably across devices and batches. At the same time, existing devices generally lack precise and consistent control over the detection environment, causing sensor signals to be greatly affected by environmental fluctuations. The established odor feature databases cannot be reliably reproduced and shared in different scenarios due to the lack of a unified benchmark. Summary of the Invention

[0005] To address the aforementioned technical problems, this disclosure provides a gas identification device, a gas identification method, and an electronic nose system.

[0006] On one hand, a gas identification device is provided, comprising: a constant-temperature gas path unit, a sensor array, a calibration unit, and a data processing unit; the constant-temperature gas path unit is used to receive the gas to be tested and provide a temperature-controllable testing environment for the gas to be tested; the sensor array is used to acquire information of the gas to be tested and convert it into an electrical signal; the calibration unit is connected to the data processing unit and is used to generate a reference signal and transmit it to the data processing unit to provide a calibration reference for the electrical signal of the sensor array; the data processing unit is connected to the constant-temperature gas path unit and also to the sensor array; the data processing unit is used to control the formation and switching of the testing environment, and to receive the electrical signal and identify the information of the gas to be tested.

[0007] In one feasible embodiment, the constant temperature gas path unit includes: a test chamber and a buffer chamber that are interconnected; the test chamber is provided with a first exhaust valve, and the buffer chamber is provided with an inlet valve for introducing the gas to be tested, an exhaust valve for extracting the gas to be tested, and a second exhaust valve; wherein, the first exhaust valve is used to discharge residual gas in the test chamber, and the second exhaust valve is used to discharge residual gas in the buffer chamber; a butterfly valve is provided between the test chamber and the buffer chamber, and the butterfly valve is used to control the opening or closing of the gas passage between the test chamber and the buffer chamber.

[0008] In one feasible embodiment, the constant temperature gas path unit further includes: a first flow meter and a second flow meter; the first flow meter is disposed on a first gas path, the first gas path is connected to the test chamber, and the first flow meter is used to adjust the flow rate of the cleaning gas entering the test chamber; the second flow meter is disposed on a second gas path, the second gas path is connected to the buffer chamber, and the second flow meter is used to adjust the flow rate of the cleaning gas entering the buffer chamber.

[0009] In one feasible embodiment, the constant temperature gas circuit unit further includes: a temperature sensor, a heating element, and a temperature controller; the temperature sensor is disposed inside the test chamber and connected to the temperature controller; the heating element is disposed inside the test chamber and connected to the temperature controller, or the heating element is disposed on the outer wall of the test chamber and connected to the temperature controller; the temperature controller is used to receive the temperature signal collected by the temperature sensor, compare whether the temperature signal is stable at a preset temperature, and if not, output a control signal to drive the heating element to work.

[0010] In one feasible embodiment, it further includes: a gas cleaning unit; the gas cleaning unit is connected to the air inlet of the constant temperature gas circuit unit to provide cleaning gas to the constant temperature gas circuit unit; before or after the gas identification device detects, the gas cleaning unit is used to inject cleaning gas into the test chamber and the buffer chamber for purging.

[0011] In one feasible embodiment, the sensor array includes: a variety of microelectromechanical system (MEMS) sensors with different gas-sensitive materials.

[0012] On the other hand, an odor recognition method for a gas recognition device is provided, applied to the aforementioned gas recognition device. The method includes: activating the gas recognition device, heating the test chamber to a preset temperature and stabilizing it; controlling a gas cleaning unit to introduce cleaning gas into the test chamber and buffer chamber respectively for purging and exhausting waste gas; introducing the gas to be tested into the buffer chamber, opening a butterfly valve to diffuse the gas to be tested in the buffer chamber into the test chamber, and collecting electrical signals from the sensor array; processing the collected electrical signals and outputting an odor recognition result based on an odor recognition model; after the test is completed, controlling the gas cleaning unit to introduce cleaning gas into the test chamber and buffer chamber respectively for purging and exhausting waste gas.

[0013] In one feasible embodiment, before activating the gas identification device and heating the test chamber to reach and stabilize the temperature at a preset temperature; or before introducing the gas to be tested into the buffer chamber, opening the butterfly valve to allow the gas to be tested in the buffer chamber to diffuse into the test chamber, and collecting the electrical signal of the sensor array; a standard gas is introduced into the test chamber, the calibration unit detects the standard gas, performs real-time calibration of the electrical signal of the sensor array, and obtains calibration parameters.

[0014] In one feasible embodiment, the controlled gas cleaning unit introduces cleaning gas into the test chamber and the buffer chamber respectively for purging and exhausting waste gas, including: providing cleaning gas to the test chamber and the buffer chamber respectively through a first gas path and a second gas path connected in parallel, and controlling the gas flow rate into the test chamber and the buffer chamber through a first flow meter and a second flow meter.

[0015] On the other hand, an electronic nose system is provided, comprising: a housing; and a gas identification device located within the housing, wherein the gas identification device is the gas identification device described above.

[0016] The technical solution provided in this disclosure has the following advantages compared with the prior art: First, the isothermal gas path unit provides a highly stable and controllable physical environment for the entire detection process. This fundamentally suppresses the interference caused by ambient temperature fluctuations on the gas sensing process, significantly improving the repeatability and comparability of the sensor response signal, and laying a reliable data foundation for subsequent accurate identification. Second, the connection between the calibration unit and the data processing unit, and the independent generation of a reference signal, provides a real-time and objective calibration reference for the sensor array output. This allows the device to actively compensate for the time drift, temperature drift, and batch differences of the sensor array itself, thereby ensuring the consistency and accuracy of the detection results during long-term use. Simultaneously, the data processing unit, through the control of the isothermal gas path unit, enables the rapid and on-demand formation and switching of the detection environment, and directly processes the calibrated sensor signal, effectively solving the problems of low accuracy and poor stability caused by uncontrollable environment, inconsistent sensors, and discrete processes in traditional gas identification. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0018] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of a gas identification device according to some embodiments; Figure 2 This is a schematic diagram of another gas identification device provided according to some embodiments; Figure 3 This is a schematic diagram of an electronic nose system according to some embodiments; Figure 4 This is a schematic diagram of another electronic nose system provided according to some embodiments.

[0020] Reference numerals: 1. Constant temperature gas circuit unit; 11. First flow meter; 12. Second flow meter; 13. Temperature sensor; 14. Heating element; 15. Temperature controller; 2. Sensor array; 3. Calibration unit; 4. Data processing unit; 5. Gas cleaning unit; A. Test chamber; B. Buffer chamber; Gas1. First exhaust valve; Gas2. Second exhaust valve; Gas3. Gas inlet valve; Gas4. Exhaust valve; Gas5. Air inlet; Gas6. Butterfly valve; 100. Gas identification device; 150. Housing; 200. Electronic nose system. Detailed Implementation

[0021] To better understand the above-mentioned objectives, features, and advantages of this disclosure, the solutions disclosed herein will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0022] Throughout this specification and claims, unless the context otherwise requires, the term "comprise" and its other forms, such as the third-person singular "comprises" and the present participle "comprising," are interpreted as open-ended and encompassing, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiments," "example," "specific example," or "some examples," etc., are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples.

[0023] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more.

[0024] In this document, the use of “configured to” implies open and inclusive language, which does not exclude devices that are configured to perform additional tasks or steps. The use of “based on” implies openness and inclusivity, because processes, steps, calculations, or other actions “based on” one or more of the stated conditions or values ​​may in practice be based on additional conditions or values ​​beyond those stated.

[0025] "A and / or B" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or B exists alone. A and B can be singular or plural.

[0026] In describing some embodiments, the term "coupled" and its derivative expressions may be used. For example, the term "coupled" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact. However, the term "coupled" may also refer to two or more components that do not have direct contact with each other but still cooperate or interact with each other. The embodiments disclosed herein are not necessarily limited to the content of this document. In describing some embodiments, the term "connected" and its derivative expressions may be used. For example, the term "connected" may be used in describing some embodiments to indicate that two or more components have direct physical or electrical contact with each other.

[0027] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this disclosure may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of this disclosure.

[0028] Based on this, such as Figure 1 The diagram shown is a schematic representation of a gas identification device according to some embodiments. The gas identification device 100 includes: a constant temperature gas path unit 1, a sensor array 2, a calibration unit 3, and a data processing unit 4.

[0029] The constant temperature gas path unit 1 is used to receive the gas to be tested and provide a temperature-controlled test environment for the gas to be tested; the sensor array 2 is used to acquire information about the gas to be tested and convert it into an electrical signal; the calibration unit 3 is connected to the data processing unit 4 and is used to generate a reference signal and transmit it to the data processing unit 4 to provide a calibration reference for the electrical signal of the sensor array 2.

[0030] The data processing unit 4 is connected to the constant temperature gas circuit unit 1 and also to the sensor array 2; the data processing unit 4 is used to control the formation and switching of the test environment, and to receive electrical signals and identify the information of the gas to be tested.

[0031] For example, a constant temperature gas circuit unit 1 consisting of a temperature controller 15 and an embedded heater has a sealable chamber inside for receiving and containing the gas to be tested.

[0032] A sensor array 2 is fixedly installed in the chamber. At the same time, an independent calibration unit 3 is also set in the chamber, which contains a reference signal source that can generate a known response. The data processing unit 4 is a constant temperature gas circuit unit 1, which simultaneously receives the electrical signal output by the sensor array 2 and the reference signal output by the calibration unit 3.

[0033] During normal operation, the data processing unit 4 first activates the constant temperature gas path unit 1 to heat the chamber to the set temperature and maintain it stable. Then, it drives the calibration unit 3 to generate a reference signal. Next, the sensor array 2 contacts the gas to be measured and generates an electrical signal. The data processing unit 4 simultaneously collects these two signals, uses the reference signal to correct and compensate the sensor response signal, and finally identifies the type or concentration information of the gas through the internal algorithm model.

[0034] In some embodiments, the sensor array 2 includes: a variety of microelectromechanical system sensors with different gas-sensitive materials.

[0035] For example, a MEMS sensor containing four different sensitive materials, with a symmetrical design, ensures full contact between the gas and the sensor.

[0036] In some embodiments, the calibration unit 3 can be a calibrated standard MEMS sensor with a sensitivity deviation of <10%. A calibration signal is generated by introducing standard gas or zero gas through an independent gas path with a micro solenoid valve, and the sensor array 2 is detachable.

[0037] In some embodiments, the calibration unit 3 can be software, which sets a standard calibration signal and transmits it to the data processing unit 4.

[0038] In some embodiments, the data processing unit 4 is a microcontroller that communicates with a host computer (computer, embedded tablet) via a wired module (USB) or a wireless module (Wi-Fi / Bluetooth / 4G / 5G).

[0039] The host computer runs customized software, which has functions such as parameter setting (target temperature, gas flow rate, test sequence), real-time monitoring (temperature curve, sensor response curve), data calibration (calling pre-calibration parameters and dynamic algorithms), and machine learning recognition (integrating support vector machine and neural network models).

[0040] In summary, by constructing a gas identification device 100 integrating a constant-temperature gas path unit 1, a sensor array 2, a calibration unit 3, and a data processing unit 4, the problems of poor repeatability and low consistency of detection results caused by environmental temperature fluctuations, individual sensor differences, and discrete data processing in traditional gas identification technologies are solved. Specifically, the data processing unit 4 uniformly controls the constant-temperature gas path unit 1 to form and maintain a precise and stable test temperature environment, while simultaneously driving the calibration unit 3 to generate a real-time reference signal. This signal is then used to dynamically calibrate and compensate the electrical signals collected by the sensor array 2 under the same environment. This significantly improves the detection accuracy and long-term stability of the device. Furthermore, through the closed-loop integration of environmental control, signal calibration, and intelligent identification, a high degree of automation and reliability in the gas identification process are achieved.

[0041] like Figure 2 As shown, in one feasible embodiment, the constant temperature gas circuit unit 1 includes a test chamber A and a buffer chamber B that are interconnected.

[0042] Test chamber A is equipped with a first exhaust valve Gas1, and buffer chamber B is equipped with an inlet valve Gas3 for introducing the gas to be tested, an exhaust valve Gas4 for extracting the gas to be tested, and a second exhaust valve Gas2.

[0043] The first exhaust valve Gas1 is used to discharge residual gas in test chamber A, and the second exhaust valve Gas2 is used to discharge residual gas in buffer chamber B.

[0044] A butterfly valve Gas6 is installed between test chamber A and buffer chamber B. The butterfly valve Gas6 is used to control the opening or closing of the gas passage between test chamber A and buffer chamber B.

[0045] For example, the constant temperature gas circuit unit 1 is a dual-chamber structure made of chemically resistant material. The test chamber A and the buffer chamber B are connected by a manual or electric butterfly valve Gas6 installed in the connecting pipe. The top of the test chamber A is equipped with a normally closed solenoid valve as the first exhaust valve Gas1, while the buffer chamber B is equipped with three valves: an air inlet throttle valve (gas3) at the top for connecting a gas bag or sampling pump, a side exhaust valve Gas4, and a normally closed solenoid valve at the bottom as the second exhaust valve Gas2. The valve bodies of all valves and the butterfly valve Gas6 are directly fixed to the outer wall of the chamber.

[0046] This design, by employing an interconnected structure with independent valves for test chamber A and buffer chamber B, and controlling their pathways via butterfly valve Gas6, solves the problems of mutual interference of gas atmospheres and difficulty in quickly switching states during cleaning, sampling, and testing in traditional single-chamber devices. Specifically, during the cleaning phase, butterfly valve Gas6 can be closed to independently and thoroughly purge both chambers. During the sampling phase, only buffer chamber B can be operated, keeping test chamber A clean and ready for testing. During the testing phase, the butterfly valve is opened to allow controlled gas diffusion. This results in a device with strict separation of process stages, low risk of cross-contamination, and high efficiency in chamber environment preparation.

[0047] Reference Figure 2 In one feasible embodiment, the constant temperature gas circuit unit 1 further includes: a first flow meter 11 and a second flow meter 12.

[0048] The first flow meter 11 is installed in the first gas path, which is connected to the test chamber A. The first flow meter 11 is used to adjust the flow rate of the cleaning gas entering the test chamber A.

[0049] The second flow meter 12 is installed in the second gas path, which is connected to the buffer chamber B. The second flow meter 12 is used to regulate the flow rate of the cleaning gas entering the buffer chamber B.

[0050] For example, a float-type flow meter with a range of 0-500 mL / min, namely the first flow meter 11, is installed in series in the first gas line, and its outlet is directly connected to the cleaning gas inlet of the test chamber A; a float-type flow meter with a range of 0-1 L / min is installed in series in the second gas line, and its outlet is connected to the cleaning gas inlet of the buffer chamber B; both flow meters are equipped with manual adjustment knobs, which can independently set and display the instantaneous gas flow rate of their respective gas lines.

[0051] By independently configuring a first flow meter 11 and a second flow meter 12 for the cleaning gas paths of test chamber A and buffer chamber B respectively, the problem of the traditional solution being unable to precisely control the cleaning airflow according to the differences in volume, structure, and degree of contamination between the two chambers is solved. Specifically, operators can independently set and control the flow rate of the cleaning gas entering test chamber A and buffer chamber B using the first flow meter 11 and the second flow meter 12, based on preset programs or actual needs. For example, a lower flow rate can be set for test chamber A to avoid damaging the precision sensor, while a higher flow rate can be set for buffer chamber B to achieve rapid and powerful purging. This gives the device the ability to perform customized cleaning for different functional chambers, thereby optimizing gas consumption and cleaning time while ensuring cleaning effectiveness.

[0052] In one feasible embodiment, the constant temperature gas circuit unit 1 further includes: a temperature sensor 13, a heating element 14, and a temperature controller 15 (see reference). Figure 3 and Figure 4 ).in, Figure 4 Number 13 refers to the wire connected to the temperature sensor; the specific temperature sensor is not shown in the diagram.

[0053] Temperature sensor 13 is disposed inside test chamber A and connected to temperature controller 15; heating element 14 is disposed inside test chamber A and connected to temperature controller 15; or, heating element 14 is disposed on the outer wall of test chamber A and connected to temperature controller 15 (see reference). Figure 4 ).

[0054] The temperature controller 15 is used to receive the temperature signal collected by the temperature sensor 13, compare whether the temperature signal is stable at the preset temperature, and if not, output a control signal to drive the heating element 14 to work.

[0055] For example, refer to Figure 3A flexible silicone heating film, serving as a heating element 14, is tightly fitted to the outer wall of test chamber A in the constant temperature gas circuit unit 1. A temperature sensor 13 is fixed at the center of the chamber. A PID temperature controller 15 is installed on the control panel of the device. Its input terminal is connected to a PT100 platinum resistance thermometer via a wire to collect temperature signals, and its output terminal is connected to a solid-state relay to control the power supply to the silicone heating film. The temperature controller 15 is internally set to a target temperature of 40.0℃. It continuously compares the collected real-time temperature with the set value and dynamically adjusts the power output to the heating film through a PID algorithm to keep the internal temperature of test chamber A stable at the preset value.

[0056] In this way, by integrating the temperature sensor 13 into the test chamber A, placing the heating element 14 on the periphery of the test chamber A, and forming a closed-loop control system with the temperature controller 15, the problem of temperature fluctuation inside the test chamber A caused by changes in ambient temperature or uneven heating during gas detection is solved. The temperature sensor 13 directly monitors the real temperature of the core area, and the temperature controller 15 adjusts the output of the heating element 14 in real time based on this feedback signal, thereby achieving active maintenance and constancy of the test environment temperature. This ensures that the sensor operating point is fixed and the gas reaction conditions are consistent, which can further improve the accuracy of gas identification.

[0057] Reference Figure 2 In one feasible embodiment, the gas identification device 100 further includes a gas cleaning unit 5.

[0058] The gas cleaning unit 5 is connected to the gas inlet Gas5 of the constant temperature gas path unit 1 to provide cleaning gas to the constant temperature gas path unit 1; before or after the gas identification device 100 detects, the gas cleaning unit 5 is used to inject cleaning gas into the test chamber A and the buffer chamber B for purging.

[0059] For example, the gas cleaning unit 5 consists of an external clean compressed air cylinder and a gas drying filter, for inputting dry compressed air (0.2MPa) from the air inlet Gas5.

[0060] Before testing, dry, clean air from the gas cylinder is used as the cleaning gas and injected into the distribution pipeline (first gas path and / or second gas path) of the constant temperature gas path unit 1 through the air inlet Gas5. It is then guided into the test chamber A and the buffer chamber B to complete the purging procedure.

[0061] In summary, by setting up an independent gas cleaning unit 5 and injecting cleaning gas into the test chamber A and buffer chamber B before and after testing, the problem of cross-contamination caused by residual gas from the previous sample during continuous testing is solved. Using dry and clean compressed air as the cleaning gas, the inner surface and internal space of the chamber are flushed at a certain flow rate within a controllable time period, which can replace and expel residual gas molecules in the cavity, thereby fundamentally ensuring the uniformity of the starting conditions for each test.

[0062] On the other hand, this application also provides an odor recognition method for a gas recognition device 100, applied to the aforementioned gas recognition device 100. The method includes: S1. Start the gas identification device 100 to heat the test chamber A until the temperature reaches and stabilizes at the preset temperature.

[0063] S2. Control gas cleaning unit 5 introduces cleaning gas into test chamber A and buffer chamber B respectively to purge and discharge waste gas.

[0064] S3. Introduce the gas to be tested into buffer chamber B, open the butterfly valve to allow the gas to be tested in buffer chamber B to diffuse into test chamber A, and collect the electrical signal of sensor array 2.

[0065] S4. Process the collected electrical signals and output the odor recognition results based on the odor recognition model.

[0066] S5. After the test is completed, control the gas cleaning unit 5 to introduce cleaning gas into the test chamber A and the buffer chamber B respectively to purge and discharge the waste gas.

[0067] The operation process of this method is as follows: First, turn on the power of the device, start the temperature control system and heat the test chamber A until its internal temperature reaches and stabilizes at the preset 40℃; then, start the cleaning program, clean compressed air is simultaneously introduced into the test chamber A and the buffer chamber B, and after purging for 30 seconds, any residual waste gas may be discharged through the exhaust valve; then, inject the standard gas sample into the buffer chamber B through the pipeline, let it stand for a short time, and then open the butterfly valve between the two chambers to allow the sample gas to diffuse naturally into the test chamber A, while simultaneously collecting the response electrical signal of the sensor array 2; subsequently, the data processing unit 4 performs filtering, feature extraction and other processing on the collected signal curves, and calls the built-in recognition model for analysis, finally displaying the identified gas type and confidence level on the interface; after the test is completed, the same cleaning process as step S2 is executed again to prepare for the next test.

[0068] By implementing the aforementioned odor recognition method, the problem of poor repeatability of detection results caused by arbitrary operating procedures and insufficient environmental preparation in traditional odor detection is solved. This process first ensures that the sensor operates at a constant temperature to eliminate temperature drift, then creates a clean and consistent initial atmosphere for detection through active purging, followed by controlled gas diffusion and signal acquisition, and finally reset through standardized cleaning. This makes the detection process highly repeatable and standardized, thereby ensuring the comparability of data and the consistency of results between different detections.

[0069] In one feasible embodiment, before activating the gas identification device 100 and heating the test chamber A to reach and stabilize the temperature at a preset temperature; or before introducing the gas to be tested into the buffer chamber B, opening the butterfly valve to allow the gas to be tested in the buffer chamber B to diffuse into the test chamber A, and before collecting the electrical signal of the sensor array 2: S0. Standard gas is introduced into test chamber A. Calibration unit 3 detects the standard gas and performs real-time calibration on the electrical signal of sensor array 2 to obtain calibration parameters.

[0070] After the equipment startup and preheating process is completed and before the formal testing begins, isobutylene standard gas of known concentration is injected from the gas cylinder into the test chamber A, which is already at the working temperature, through a dedicated pipeline. At this time, the high-precision reference sensor in the calibration unit 3 integrated in the test chamber A immediately responds to the standard gas and generates a reference signal.

[0071] Meanwhile, sensor array 2 also generates its own response electrical signals to the same standard gas environment; data processing unit 4 synchronously acquires these reference signals and electrical signals, and through comparative analysis, calculates the gain and offset calibration parameters of each sensor in the current state, and stores these parameters for subsequent signal correction of actual samples.

[0072] In this way, by introducing a real-time calibration step that introduces standard gas into test chamber A and is detected by calibration unit 3, the problem of measurement reference drift caused by long-term aging of the sensor, cumulative environmental pollution, or short-term performance fluctuations is solved. The dynamic acquisition of calibration parameters that reflect the actual state of the current sensor enables the device to automatically correct the sensor's operating point before each test, thereby ensuring the accuracy of the subsequently acquired gas signals.

[0073] In one feasible embodiment, the control gas cleaning unit 5 introduces cleaning gas into the test chamber A and the buffer chamber B respectively to purge and discharge waste gas, including: S21. Cleaning gas is supplied to test chamber A and buffer chamber B through the first gas path and the second gas path connected in parallel, respectively, and the gas flow rate into test chamber A and buffer chamber B is controlled by the first flow meter 11 and the second flow meter 12.

[0074] By using a first and a second air path connected in parallel and equipped with a first flow meter 11 and a second flow meter 12 respectively to control the distribution of cleaning gas, the operator can set and precisely control the flow rate of the cleaning gas entering the test chamber A and the buffer chamber B.

[0075] For example, a gentle purging with a low flow rate is used for test chamber A, which is small in volume, has a precise structure, and requires protection for the sensor; while a strong flushing with a high flow rate is used for buffer chamber B, which has a larger volume and may contain high concentrations of residual samples.

[0076] This makes the cleaning process highly flexible and targeted, thereby significantly improving cleaning efficiency and optimizing the consumption of cleaning gas while ensuring the same level of cleanliness. Figure 3 and Figure 4 This is a schematic diagram of an electronic nose system according to some embodiments. The electronic nose system 200 includes a housing 150 and a gas identification device 100 disposed in the housing 150.

[0077] In some embodiments, this disclosure also provides a vehicle including the electronic nose system 200 described above. The vehicle may be selected from any one of a battery electric vehicle (BEV), a hybrid electric vehicle (HEV), or a plug-in hybrid electric vehicle (PHEV).

[0078] In vehicles, the electronic nose system 200 is used for applications such as in-vehicle air quality monitoring, new energy vehicle battery safety monitoring, personalized smart cockpit experience, supplementing environmental perception in autonomous driving scenarios, and quality control in automobile manufacturing and after-sales service.

[0079] In some embodiments, this disclosure also provides an artificial intelligence device, which includes the electronic nose system 200 described above and a neural network module. The neural network module is configured to generate a gas recognition signal based on the target concentration curve output by the electronic nose system 200.

[0080] In some embodiments, the electronic nose system 200 can also be applied to the field of food safety, for example, in scenarios such as screening the quality and safety of food raw materials, monitoring pollution and quality during processing, grading and identifying the authenticity of finished products, monitoring cold chain transportation and storage environment, and rapid detection and risk warning at the consumer end.

[0081] In some embodiments, the electronic nose system 200 can also be applied to the field of industrial safety. For example, it can be applied to scenarios such as real-time monitoring of industrial waste gas, odor control in water and solid waste treatment, safety control of hazardous chemicals (such as leak emergency response, warehousing and transportation detection and odor concentration detection at the plant boundary), and circular economy and resource utilization.

[0082] In some embodiments, the electronic nose system 200 can also be applied in the field of medical and health care. For example, it can be used for screening and diagnosis, early warning of infection and complications, personalized medicine and health management (medication effect evaluation and sub-health status monitoring), special group care and assistive medical care and other scenarios.

[0083] In some embodiments, the electronic nose system 200 can also be applied to the smart home field.

[0084] The above description is merely a specific embodiment of this disclosure, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A gas identification device, characterized in that, include: Thermostatic gas path unit, sensor array, calibration unit, and data processing unit; The constant temperature gas circuit unit is used to receive the gas to be tested and provide a temperature-controlled testing environment for the gas to be tested. The sensor array is used to acquire information about the gas to be measured and convert it into an electrical signal; The calibration unit is connected to the data processing unit and is used to generate a reference signal and transmit it to the data processing unit to provide a calibration reference for the electrical signals of the sensor array. The data processing unit is connected to the constant temperature gas path unit and also to the sensor array; the data processing unit is used to control the formation and switching of the test environment, and to receive the electrical signal and identify the information of the gas to be tested.

2. The gas identification device according to claim 1, characterized in that, The constant temperature gas circuit unit includes: a test chamber and a buffer chamber that are interconnected; The test chamber is equipped with a first exhaust valve, and the buffer chamber is equipped with an inlet valve for introducing the gas to be tested, an exhaust valve for extracting the gas to be tested, and a second exhaust valve. The first exhaust valve is used to discharge residual gas in the test chamber, and the second exhaust valve is used to discharge residual gas in the buffer chamber. A butterfly valve is provided between the test chamber and the buffer chamber, and the butterfly valve is used to control the opening or closing of the gas passage between the test chamber and the buffer chamber.

3. The gas identification device according to claim 2, characterized in that, The constant temperature gas circuit unit also includes: a first flow meter and a second flow meter; The first flow meter is installed in the first gas path, which is connected to the test chamber. The first flow meter is used to adjust the flow rate of the cleaning gas entering the test chamber. The second flow meter is installed in the second gas path, which is connected to the buffer chamber. The second flow meter is used to regulate the flow rate of the cleaning gas entering the buffer chamber.

4. The gas identification device according to claim 3, characterized in that, The constant temperature gas circuit unit also includes: a temperature sensor, a heating element, and a temperature controller; The temperature sensor is disposed inside the test chamber and connected to the temperature controller; the heating element is disposed inside the test chamber and connected to the temperature controller, or the heating element is disposed on the outer wall of the test chamber and connected to the temperature controller. The temperature controller is used to receive the temperature signal collected by the temperature sensor, compare whether the temperature signal is stable at the preset temperature, and if not, output a control signal to drive the heating element to work.

5. The gas identification device according to claim 2, characterized in that, Also includes: Gas cleaning unit; The gas cleaning unit is connected to the air inlet of the constant temperature gas circuit unit to provide cleaning gas to the constant temperature gas circuit unit; Before or after detection, the gas cleaning unit of the gas identification device is used to inject cleaning gas into the test chamber and buffer chamber for purging.

6. The gas identification device according to claim 1, characterized in that, The sensor array includes: a variety of microelectromechanical system sensors with different gas-sensitive materials.

7. An odor recognition method for a gas recognition device, applied to the gas recognition device as described in any one of claims 1 to 6, characterized in that, include: The gas identification device is activated to heat the test chamber until the temperature reaches and stabilizes at the preset temperature. The control gas cleaning unit introduces cleaning gas into the test chamber and buffer chamber respectively to purge and discharge waste gas. The gas to be tested is introduced into the buffer chamber, and the butterfly valve is opened to allow the gas to be tested in the buffer chamber to diffuse into the test chamber, and the electrical signal of the sensor array is collected. The collected electrical signals are processed, and odor recognition results are output based on the odor recognition model; After the test is completed, the control gas cleaning unit introduces cleaning gas into the test chamber and the buffer chamber respectively to purge and discharge the waste gas.

8. The odor recognition method according to claim 7, characterized in that, Before activating the gas identification device and heating the test chamber to reach and stabilize the temperature at a preset temperature; or before introducing the gas to be tested into the buffer chamber, opening the butterfly valve to allow the gas to be tested in the buffer chamber to diffuse into the test chamber, and collecting the electrical signal of the sensor array. A standard gas is introduced into the test chamber, and the calibration unit detects the standard gas to perform real-time calibration of the electrical signal of the sensor array and obtain calibration parameters.

9. The odor recognition method according to claim 7, characterized in that, The controlled gas cleaning unit introduces cleaning gas into the test chamber and the buffer chamber respectively to purge and discharge waste gas, including: Cleaning gas is supplied to the test chamber and the buffer chamber through a first gas path and a second gas path connected in parallel, respectively, and the gas flow rate into the test chamber and the buffer chamber is controlled by a first flow meter and a second flow meter.

10. An electronic nose system, characterized in that, include: case; A gas identification device is located inside the housing, and the gas identification device is the gas identification device as described in any one of claims 1-6.

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