Odor detection device and odor detection system

Abstract

To provide a technology for determining which odor sensors have deteriorated when some of a plurality of odor sensors have deteriorated.SOLUTION: An odor detection device 100 comprises three or more odor sensors 102A, 102B, 102C, 102D, a storage unit 104 that stores normal range data obtained by learning a normal range of output values of the odor sensors 102A, 102B, 102C, 102D for each odor component, and a determination unit 107 that determines deterioration of each of the plurality of odor sensors. The determination unit 107 compares the output value of each of the plurality of odor sensors with the normal range data, and when an odor component containing a majority of the measured value of each of the plurality of odor sensors 102A, 102B, 102C, 102D is found within the normal range, determines that the odor sensors 102A, 102B, 102C, 102D whose odor components are out of the normal range have deteriorated.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an odor detection system including an odor detection device, and more particularly to detecting deterioration of an odor sensor mounted in the odor detection device. [Background technology]

[0002] Odor detection devices that determine the type or concentration of an odor from the output values ​​of multiple odor sensors with different characteristics are known. Regarding odor discrimination using multiple odor sensors, for example, International Publication No. 2019 / 102654 (Patent Document 1) discloses an odor detection device equipped with multiple odor sensors. This odor detection device "includes multiple odor sensors with different odor-responsive characteristics. The odor detection device identifies odor components (e.g., nonenal, diacetyl, isovaleric acid) contained in the gas to be measured and their concentrations based on the output values ​​of the multiple odor sensors, and determines the type of odor (e.g., aging odor, middle-aged oily odor, sweat odor) based on the identified odor components and their concentrations, and outputs the determined type of odor" (see [Abstract]).

[0003] Furthermore, other techniques related to odor discrimination are disclosed in, for example, International Publication No. 2019 / 102660 (Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2019 / 102654 [Patent Document 2] International Publication No. 2019 / 102660 Summary of the Invention [Problem to be solved by the invention]

[0005] According to the techniques disclosed in Patent Documents 1 and 2, when a part of a plurality of odor sensors deteriorates, it is not possible to determine which odor sensor has deteriorated. Therefore, there is a need for a technique for determining which odor sensor has deteriorated when a part of a plurality of odor sensors deteriorates.

[0006] The present disclosure has been made in consideration of the above-described background, and in one aspect, the purpose is to provide a technology for determining which odor sensor has deteriorated when some of multiple odor sensors have deteriorated. [Means for solving the problem]

[0007] According to one embodiment, there is provided an odor detection device. The odor detection device includes three or more odor sensors, a memory unit for storing normal range data obtained by learning the normal range of the output values ​​of each odor sensor for each odor component, and a determination unit for determining deterioration of each of the odor sensors. The determination unit compares the output values ​​of each of the odor sensors with the normal range data, and when an odor component is found for which the majority of the actual measured values ​​of each of the odor sensors fall within the normal range, determines that the odor sensor that is outside the normal range for the found odor component has deteriorated.

[0008] In an odor detection device according to a certain aspect, the judgment unit judges that the odor components detected by the multiple odor sensors are indistinguishable based on the fact that no odor components are found in the normal range data that include a majority of the actual measured values ​​of each of the multiple odor sensors within the normal range.

[0009] According to one aspect, the odor detection device further includes a correction unit that corrects the actual measurement value of a deteriorated odor sensor. The correction unit compares the actual measurement value of a certain odor sensor with an approximation line of the correlation between the concentration of each odor component and the output value of the certain odor sensor, which has been learned in advance, to determine whether the deterioration of the certain odor sensor is progressing along the approximation line, and corrects the actual measurement value of the certain odor sensor so that the actual measurement value of the certain odor sensor approaches the approximation line based on whether the deterioration of the certain odor sensor is progressing along the approximation line.

[0010] In an odor detection device according to a certain aspect, a judgment unit outputs a judgment result indicating that a certain odor sensor has deteriorated based on the difference between the actual measurement value of a certain odor sensor and the output value indicated by the approximation line exceeding a predetermined threshold value.

[0011] In an odor detection device according to a certain aspect, a determination unit outputs an estimated time until a certain odor sensor becomes unusable, based on a regression curve obtained from time-dependent data of actual measured values ​​of the certain odor sensor.

[0012] In an odor detection device according to one aspect, the memory unit further stores recorded data of deterioration times of the odor sensors measured in the past. The determination unit compares the actual measured value of a certain odor sensor with the recorded data and outputs an estimated time until the certain odor sensor becomes unusable.

[0013] According to another embodiment, an odor detection system is provided. The odor detection system includes a plurality of odor detection devices and a communication device. Each of the plurality of odor detection devices includes three or more odor sensors, a memory unit for storing normal range data obtained by learning the normal range of the output values ​​of each odor sensor for each odor component, and a determination unit for determining deterioration of each of the plurality of odor sensors. The determination unit compares the output value of each of the plurality of odor sensors with the normal range data, and if an odor component is found for which the majority of the actual measured values ​​of each of the plurality of odor sensors are within the normal range, determines that the odor sensor that is outside the normal range for the found odor component has deteriorated. The communication device includes a communication unit for communicating with each of the plurality of odor detection devices and a display unit capable of displaying the results of the deterioration determination obtained from each of the plurality of odor detection devices.

[0014] In an odor detection system according to a certain aspect, the judgment unit judges that the odor components detected by the multiple odor sensors are indistinguishable based on the fact that no odor components are found in the normal range data that include a majority of the actual measured values ​​of each of the multiple odor sensors within the normal range.

[0015] In an odor detection system according to one aspect, the odor detection device further includes a correction unit that corrects the actual measurement value of a deteriorated odor sensor. The correction unit compares the actual measurement value of a certain odor sensor with an approximation line of the correlation between the concentration of each odor component and the output value of the certain odor sensor, which has been learned in advance, to determine whether the deterioration of the certain odor sensor is progressing along the approximation line, and corrects the actual measurement value of the certain odor sensor so that the actual measurement value of the certain odor sensor approaches the approximation line based on whether the deterioration of the certain odor sensor is progressing along the approximation line.

[0016] In an odor detection system according to a certain aspect, a judgment unit transmits a judgment result indicating that a certain odor sensor has deteriorated to a communication device based on the difference between the actual measurement value of a certain odor sensor and the output value indicated by the approximation line exceeding a predetermined threshold.

[0017] In an odor detection system according to a certain aspect, a determination unit transmits to a communication device an estimated time until a certain odor sensor becomes unusable, based on a regression curve obtained from time-lapse data of actual measured values ​​of the certain odor sensor.

[0018] In an odor detection system according to an aspect, the memory unit further stores recorded data of deterioration times measured in the past for the odor sensors. The determination unit compares an actual measurement value of a certain odor sensor with the recorded data, and transmits an estimated time until the certain odor sensor becomes unusable to the communication device.

[0019] In an odor detection system according to one aspect, the communication device further includes a complementation unit that, based on deterioration of a first odor sensor of a first odor detection device included in the plurality of odor detection devices, uses an actual measurement value of a first odor sensor of a second odor detection device included in the plurality of odor detection devices instead of the actual measurement value of the first odor sensor of the first odor detection device to obtain a detection result. [Effects of the Invention]

[0020] According to one embodiment, when some of the multiple odor sensors have deteriorated, it is possible to determine which odor sensor has deteriorated.

[0021] The above and other objects, features, aspects and advantages of the present disclosure will become apparent from the following detailed description of the disclosure taken in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 shows an example of a configuration of an odor detection system 10 according to an embodiment. [Figure 2] FIG. 1 is a diagram showing an example of a configuration in which a plurality of odor detection devices 100 are used. [Figure 3] 10 is a diagram showing an example of the configuration of an odor type determination table 106, and an example of a procedure for identifying odors and determining whether an odor sensor 102 has deteriorated. [Figure 4] 1 is a diagram showing an example of a process for predicting deterioration of an odor sensor 102 in an odor detection device 100 and a process for correcting the odor sensor. FIG. [Figure 5] 10 is a flowchart showing an example of a processing procedure for identifying a deteriorated odor sensor 102 in the odor detection system 10. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, embodiments of the technical concept according to the present disclosure will be described with reference to the drawings. In the following description, the same components are denoted by the same reference numerals. The names and functions of the components are also the same. Therefore, detailed descriptions thereof will not be repeated.

[0024] 1 is a diagram showing an example of the configuration of an odor detection system 10 according to the present embodiment. Odor detection system 10 includes an odor detection apparatus 100 and a communication device 120. Odor detection apparatus 100 and communication device 120 are equipped with a short-range wireless communication function such as Bluetooth (registered trademark) and are capable of communicating with each other.

[0025] The odor detection device 100 mainly comprises a control unit 101, odor sensors 102A, 102B, 102C, and 102D (collectively referred to as "odor sensors 102"), an ADC (Analog to Digital Converter) 103, a memory unit 104, an operation switch 110, a battery 111, and a communication unit 112. These components can communicate with each other via an internal bus 113. The memory unit 104 also stores an identification unit 105, an odor type determination table 106, a determination unit 107, a correction unit 108, and characteristic data 109.

[0026] The control unit 101 can execute programs for realizing various functions of the odor detection device 100. The control unit 101 is configured, for example, by at least one integrated circuit. The integrated circuit may be configured, for example, by at least one CPU (Central Processing Unit), at least one FPGA (Field Programmable Gate Array), or a combination of these. The control unit 101 may also include RAM such as DRAM (Dynamic Random Access Memory) or SRAM (Static Random Access Memory) for storing programs executed by the CPU. In this case, the control unit 101 can load programs for realizing various functions of the odor detection device 100 from the storage unit 104 into the RAM and execute the programs.

[0027] Odor sensor 102 converts the concentration of the odor component (gas, etc.) to be detected into an electrical signal. In one aspect, odor sensor 102 may be a so-called analog sensor. In this case, odor sensor 102 converts the concentration of the odor component (gas, etc.) to be detected into a voltage or current and outputs it. In another aspect, odor sensor 102 may be a so-called digital sensor. In this case, odor sensor 102 may output the odor component (gas, etc.) to be detected as digital data (e.g., numerical data of approximately 8 to 32 bits). In another aspect, odor sensors 102A, 102B, 102C, and 102D may have different odor response characteristics.

[0028] For example, the odor sensor 102 may be realized by a gas sensor for detecting VOCs (Volatile Organic Compounds), a gas sensor for detecting CO, a gas sensor for detecting hydrogen, a gas sensor for detecting hydrocarbons, a gas sensor for detecting alcohol, a gas sensor for detecting tobacco, or a combination of these. Note that each of the odor sensors 102A, 102B, 102C, and 102D does not necessarily react to only one type of odor component, but may also react to multiple odor components. Odor components are chemical substances that make up odors.

[0029] In this specification, the odor detection device 100 is illustrated as including four odor sensors 102A, 102B, 102C, and 102D, as an example, but the number of odor sensors 102 included in the odor detection device 100 is not limited to this. In certain aspects, the odor detection device 100 may include any number of odor sensors 102, such as three or more.

[0030] ADC 103 converts analog signals output from odor sensors 102A, 102B, 102C, and 102D into digital signals and outputs them to control unit 101. In one aspect, if odor sensors 102A, 102B, 102C, and 102D are digital sensors, odor detection device 100 may not include ADC 103. In this case, odor sensors 102A, 102B, 102C, and 102D may include an integrated circuit (IC) that outputs a digital signal.

[0031] Storage unit 104 is a non-volatile memory that stores various programs executed by control unit 101 and various data referenced by control unit 101. In one aspect, storage unit 104 may be realized by a hard disk drive (HDD), a solid state drive (SSD), an erasable programmable read only memory (EPROM), an electrically erasable programmable read only memory (EEPROM), a flash memory, or the like.

[0032] The identification unit 105 is a program for detecting odors or a trained model generated by machine learning. The identification unit 105 is generated, for example, by the following procedure.

[0033] First, prepare multiple different odor components at different concentrations. For example, prepare odor component X at concentrations 1, 2, and 3, odor component Y at concentrations 1, 2, and 3, and odor component Z at concentrations 1, 2, and 3.

[0034] Next, output values ​​(waveforms) of odor sensors of the same type as odor sensors 102A, 102B, 102C, and 102D (hereinafter referred to as "learning odor sensors") are obtained for each concentration of each odor component. When three types of odor components with three levels of concentration are prepared as described above, output values ​​X1 to X3 of the learning odor sensors when odor component X is detected at concentrations 1 to 3, output values ​​Y1 to Y3 of the learning odor sensors when odor component Y is detected at concentrations 1 to 3, and output values ​​Z1 to Z3 of the learning odor sensors when odor component Z is detected at concentrations 1 to 3 are obtained.

[0035] Next, a set of data is provided to the learning engine as training data, where the combination of output values ​​from each training odor sensor is used as input and the odor components and their concentrations are used as output. The learning engine generates a trained model based on the provided training data. The trained model may function as the identification unit 105, or may be used as a library referenced by the identification unit 105.

[0036] The above-mentioned "learning odor sensor" is, for example, a sensor having the same characteristics as each of the odor sensors 102A, 102B, 102C, and 102D (e.g., odor sensors with the same model number). Furthermore, although the use of a learning odor sensor has been described as an example, machine learning may also be performed using the odor sensors 102A, 102B, 102C, and 102D that are actually installed in the odor detection device 100.

[0037] In one aspect, the machine learning may use a neural network, particularly a learning vector quantization (LVQ) neural network.

[0038] The odor components used for learning can be selected arbitrarily depending on the application of the odor detection system 10. When the application is checking for body odor, the odor components used for learning may be, for example, components that cause malodors, such as nonenal, diacetyl, isovaleric acid, and ammonia. Nonenal is a component that causes body odor associated with aging (body odor that occurs with aging). Diacetyl is a component that causes middle-aged oily odor (a greasy body odor common among middle-aged men). Isovaleric acid is a component that causes sweat odor (body odor caused by sweat).

[0039] The odor type determination table 106 is a table that associates odor types, concentrations, intensities (odor levels), and the ranges of output values ​​of each of the odor sensors 102A, 102B, 102C, and 102D. The odor type determination table 106 is generated during the machine learning process described above. The ranges of output values ​​of each of the odor sensors 102A, 102B, 102C, and 102D are the ranges of expected values ​​that are predicted to be output when a certain odor component is detected by each odor sensor 102 when the odor sensor 102 is operating normally. In some aspects, the odor type determination table 106 may be expressed as a relational database table or in any other data format, such as JSON (JavaScript (registered trademark) Object Notation). The items in the odor type determination table 106 will be described below with reference to FIG. 3.

[0040] In one aspect, odor detection device 100 may determine the type, concentration, and intensity of the detected odor based on the trained model by inputting the actual measurement values ​​of each of odor sensors 102A, 102B, 102C, and 102D into identification unit 105. In another aspect, odor detection device 100 may determine the type, concentration, and intensity of the detected odor by comparing the actual measurement values ​​of each of odor sensors 102A, 102B, 102C, and 102D with the ranges of output values ​​of each of odor sensors 102A, 102B, 102C, and 102D in odor type discrimination table 106.

[0041] The odor types may correspond to odor components, or may be human classifications of odors with certain characteristics. For example, when the odor detection device 100 is used as a body odor checker, the three major body odors, namely, body odor due to aging, middle-aged oily odor, and sweat odor, may be cited as odor types.

[0042] The determination unit 107 can also detect partial deterioration of the odor sensors 102A, 102B, 102C, and 102D by using the odor type determination table 106. Details of detecting partial deterioration of the odor sensors 102A, 102B, 102C, and 102D will be described later with reference to FIG.

[0043] When some of the odor sensors 102A, 102B, 102C, and 102D deteriorate, the correction unit 108 corrects the output value of the deteriorated odor sensor. When the odor detection device 100 is used for a long period of time, some of the odor sensors 102A, 102B, 102C, and 102D may deteriorate. For example, when odor sensor 102D deteriorates, the output value of odor sensor 102D may change. This may cause the odor detection device 100 to be unable to correctly distinguish odor components. However, when the degree of deterioration of the deteriorated odor sensor 102D is small (when the amount of change in the output value of odor sensor 102D is small), the effect of deterioration can be suppressed by correcting the output value of odor sensor 102D (e.g., by multiplying by a coefficient). Details of correcting the output value of odor sensor 102 will be described later with reference to FIG. 4.

[0044] The characteristic data 109 is data indicating the characteristics of each odor sensor 102 referenced by the correction unit 108. By referencing the characteristic data 109, the correction unit 108 can calculate a correction value (coefficient) for correcting each odor sensor 102.

[0045] Identification unit 105 and correction unit 108 may be realized as a program executed by control unit 101. In another aspect, identification unit 105 and correction unit 108 may be realized as hardware such as an ASIC (Application Specific Integrated Circuit) having the above-described functions. In this case, identification unit 105 and correction unit 108 are provided outside storage unit 104.

[0046] Operation switch 110 may be a power switch for turning on / off the power of odor detection device 100, a switch for the user to start the odor measurement process in odor detection device 100, or a switch having both functions. Operation switch 110 may also include multiple switches. In one aspect, odor detection device 100 may be equipped with a liquid crystal monitor and a touch panel.

[0047] Battery 111 supplies power to each component of odor detection device 100. Battery 111 may be a detachable dry cell battery, a rechargeable battery, or the like. In one aspect, odor detection device 100 may further include a charging circuit for charging battery 111, and a power management circuit for managing the voltage and current of battery 111.

[0048] Communication unit 112 transmits and receives data to and from communication device 120. In one aspect, communication unit 112 may be implemented as a Bluetooth module and communicate with communication device 120 in accordance with the Bluetooth Low Energy (BLE) communication standard. In another aspect, communication unit 112 may be implemented by a wired Local Area Network (LAN) port, a Wi-Fi (registered trademark) (Wireless Fidelity) module, or the like. In yet another aspect, communication unit 112 may transmit and receive data using a communication protocol such as Transmission Control Protocol / Internet Protocol (TCP / IP) or User Datagram Protocol (UDP).

[0049] The communication device 120 can provide various services, such as receiving various information from one or more odor detection devices 100 and displaying it to the user. The communication device 120 may also have a function for determining deterioration of each odor sensor 102 in each odor detection device 100, a function for correcting the output value of each odor sensor 102, and a function for complementing odor sensors 102 among multiple odor detection devices 100. The function for complementing odor sensors 102 among multiple odor detection devices 100 is, for example, a function for, when odor sensor 102A of one odor detection device 100 deteriorates, using the output value of odor sensor 102A of another odor detection device 100 instead. These functions will be described below with reference to FIG. 5. Furthermore, the communication device 120 may store, as programs in the storage unit 126, a deterioration determination unit (not shown) for realizing a deterioration determination function for each odor sensor in each odor detection device 100, a correction unit (not shown) for realizing a correction function for the output value of each odor sensor 102, and a complementation unit (not shown) for realizing a complementation function for the odor sensors 102 among the multiple odor detection devices 100. In this case, the control unit 121 may read each program into RAM and execute it.

[0050] Furthermore, communication device 120 may have the ability to install and execute applications for providing various services to the user. In one aspect, communication device 120 may be a device owned by the user, such as a personal computer, a smartphone, or a tablet. In another aspect, communication device 120 may be a server that collects information from multiple odor detection devices 100. In this case, communication device 120 may be realized as one or more server devices, or instances (virtual machines) on one or more server devices or in a cloud environment.

[0051] Communication device 120 mainly comprises a control unit 121, a display unit 122, an operation unit 123, a first communication unit 124, a second communication unit 125, a storage unit 126, a speaker 127, and a microphone 128.

[0052] The control unit 121 may execute programs for implementing various functions of the communication device 120. The control unit 121 may be configured, for example, by at least one integrated circuit. The integrated circuit may be configured, for example, by at least one CPU, at least one FPGA, or a combination thereof.

[0053] The display unit 122 can be realized by a liquid crystal display, an organic EL (Electro-Luminescence) display, or the like.

[0054] The operation unit 123 is configured by buttons and / or a touch panel or the like laminated on the display unit 122. An operation signal corresponding to each button and the position of the touch operation is output to the control unit 121.

[0055] The first communication unit 124 communicates with an external device connected to a communication network wirelessly or via a wired connection. In one aspect, the first communication unit 124 may be implemented by a wired LAN port, a Wi-Fi module, or the like. In this case, the first communication unit 124 may transmit and receive data using a communication protocol such as TCP / IP or UDP. The second communication unit 125 functions as an interface for short-range communication such as Bluetooth wireless communication. The communication device 120 can communicate with the odor detection device 100 via either the first communication unit 124 or the second communication unit 125.

[0056] The storage unit 126 is a non-volatile memory that stores various programs executed by the control unit 121 and various data referenced by the control unit 121. In one aspect, the storage unit 126 may be realized by an HDD, an SSD, an EPROM, an EEPROM, a flash memory, or the like. The storage unit 126 may store an application that uses odor data acquired from the odor detection device 100.

[0057] Speaker 127 converts electrical signals received from an external device via first communication unit 124 into audio signals and outputs audio. Speaker 127 can also output audio based on an audio file being played by an application.

[0058] The microphone 128 detects sound waves, converts them into electrical signals, and outputs them to the control unit 121 or the first communication unit 124 .

[0059] 2 is a diagram showing an example of a configuration in which multiple odor detection devices 100 are used. A communication device 120 can communicate with any number of odor detection devices 100, including one or more odor detection devices 100. The number of odor detection devices 100 required varies depending on the services provided by the communication device 120 or the applications executed by the communication device 120.

[0060] As one example, in the case of an application such as a body odor checker, the communication device 120 only needs to communicate with one odor detection device 100. As another example, in the case where the communication device 120 provides a safety confirmation service or a disaster notification service used in a home, a nursing home, a factory, a laboratory, or the like, the communication device 120 may communicate with multiple odor detection devices 100 located in the home, nursing home, or the like. The communication device 120 may also function as a server and provide services to multiple terminals using information aggregated from the odor detection devices 100.

[0061] 3 is a diagram showing an example of the configuration of odor type determination table 106, and an example of the procedure for identifying odors and determining whether an odor sensor 102 has deteriorated. The procedure for determining whether an odor sensor 102 has deteriorated in odor detection device 100 will be described with reference to FIG.

[0062] In a first step, each of odor sensors 102A, 102B, 102C, and 102D detects or measures measurement target gas 301. Then, each of odor sensors 102A, 102B, 102C, and 102D outputs an output value (hereinafter, sometimes referred to as an "actual measurement value") that is the measurement result of measurement target gas 301 to identification unit 105. In one aspect, this process can be realized by control unit 101 executing a program that outputs an actual output signal to identification unit 105. In another aspect, odor detection device 100 may be provided with a function, as hardware, that outputs the actual output signal to identification unit 105.

[0063] In the second step, the identification unit 105 identifies the type, concentration, and intensity of the measurement target gas 301. As an example, the identification unit 105 of the odor detection device 100 may input the actual measurement values ​​of each of the odor sensors 102A, 102B, 102C, and 102D into the trained model, thereby obtaining the type, concentration, and intensity of the measurement target gas 301 as the output of the trained model.

[0064] As another example, odor detection device 100 or identification unit 105 may determine the type, concentration, and intensity of the detected odor by comparing the actual measurement values ​​of each of odor sensors 102A, 102B, 102C, and 102D with the range of output values ​​of each of odor sensors 102A, 102B, 102C, and 102D in odor type discrimination table 106. In this case, odor detection device 100 compares the actual measurement values ​​of each odor sensor 102 with the range of output values ​​of each odor sensor 102 in each record of odor type discrimination table 106.

[0065] The range of the output value of each odor sensor 102 is the range of the output value that is expected to be output when each odor sensor 102 observes a gas of the type and concentration of its record under normal conditions (hereinafter, it may also be simply referred to as the "range of normal values"). In a certain aspect, the range of normal values may be determined based on, for example, the machine learning teacher data obtained through experiments. In other aspects, the range of normal values may be determined based on the result of causing the discrimination unit 105 to discriminate odor components by concentration (based on the output result of the discrimination unit 105 when each odor sensor 102 is normal).

[0066] The discrimination unit 105 may select, as the measurement result, the "type" and "concentration" of the gas of the record 302 in which the range of normal values of each odor sensor 102 includes the majority of the actually measured values of each odor sensor 102. The discrimination unit 105 outputs a signal indicating the selected measurement result to the control unit 101. The signal indicating the measurement result may include the type, concentration, level of the measurement target gas 301, and the actually measured values of each odor sensor 102. In the example of FIG. 3, the discrimination unit 105 selects "type: X" and "concentration: 1 ppm < x ≦ 5 ppm" as the measurement result.

[0067] In a certain situation, the identification unit 105 may select, as the identification result, a record having a normal range that includes the most combinations of measured values. For example, assume that the measured value of the odor sensor 102A is "a3 < a ≤ a4", the measured value of the odor sensor 102B is "b3 < b ≤ b4", the measured value of the odor sensor 102C is "c3 < c ≤ c4", and the measured value of the odor sensor 102D is "d5 < d ≤ d6". In this case, since record 302 includes the actual output signals of the odor sensors 102A, 102B, and 102C within the normal range, the degree of coincidence is the highest. Therefore, the identification unit 105 selects record 302 ("type: X", "concentration: 1 ppm < x ≤ 5 ppm", "level: 3") as the identification result and outputs a signal indicating the identification result to the control unit 101. Further, when there is no record having a normal range that includes the measured values of more than half or a certain number or more (for example, 3 / 4 or more of the sensors) of the measured values, the identification unit 105 may output a signal indicating identification failure to the control unit 101. Thus, by using the odor type discrimination table 106, the odor detection device 100 can identify the measurement target gas 301 even when the measured values deviate slightly from the learning results of machine learning due to deterioration of some of the odor sensors 102.

[0068] In the third step, the determination unit 107 obtains the measurement result (which may include the type, concentration, level of the measurement target gas 301, and the measured values of each odor sensor 102) via the control unit 101 or directly from the identification unit 105. Then, the determination unit 107 compares the measurement result with the odor type discrimination table 106 to determine whether there is a deteriorated odor sensor 102 and, if there is a deteriorated odor sensor 102, identify which odor sensor 102 has deteriorated.

[0069] More specifically, first, the determination unit 107 compares the measured values of each odor sensor 102 with the normal range of each odor sensor 102, and determines whether there exists a record that includes the majority of the measured values of each odor sensor 102 within the normal range. For example, assume that the measured value of odor sensor 102A is "a3 < a ≤ a4", the measured value of odor sensor 102B is "b3 < b ≤ b4", the measured value of odor sensor 102C is "c3 < c ≤ c4", and the measured value of odor sensor 102D is "d5 < d ≤ d6". In this case, record 302 includes the measured values of the majority of odor sensors 102A, 102B, 102C (3 out of 4 measured values) within the normal range. Therefore, the determination unit 107 determines that there exists a record 302 that includes the majority of the measured values of each odor sensor 102 within the normal range, and outputs a signal indicating the determination result to the control unit 101.

[0070] Next, identify the odor sensor 102 that outputs the measured value not included in the normal range of record 302. In this example, the measured value "d5 < d ≤ d6" of odor sensor 102D is not included in the normal range "d3 < d ≤ d4" of odor sensor 102D in record 302. In this case, the determination unit 107 determines that odor sensor 102D has deteriorated. This is because the majority of odor sensors 102A, 102B, 102C are normal as they output the measured values within the normal range in record 302, and it is highly likely that the minority odor sensor 102D, which outputs the measured value outside the normal range in record 302, has deteriorated.

[0071] As another example, if there are 7 odor sensors 102, and the measured values of 5 of them are included in the normal range of a record while the measured values of the remaining 2 odor sensors 102 are outside the normal range of the record, the determination unit 107 may determine that the 2 odor sensors 102 (the minority) that output the measured values outside the normal range have deteriorated.

[0072] As another example, if the number of odor sensors 102 is even, and the actual measurement values ​​of half of the odor sensors 102 are within the normal range of a certain record, and the actual measurement values ​​of the remaining half of the odor sensors 102 are outside the normal range of a certain record, the determination unit 107 will not be able to determine which odor sensors 102 have deteriorated (the minority odor sensors 102), and will output a signal indicating an inability to determine or an error to the control unit 101.

[0073] In one aspect, the identification unit 105 and the determination unit 107 may be implemented as a single program module or hardware. In another aspect, the second and third steps may be executed simultaneously. Furthermore, in another aspect, the communication device 120 may include the identification unit 105, the odor type determination table 106, and the determination unit 107, and may execute the process described with reference to FIG. 3. In this case, one or more odor detection devices 100 communicating with the communication device 120 transmit the actual measurement values ​​of each odor sensor 102 to the communication device 120. The communication device 120 may compare the actual measurement values ​​of each odor sensor 102 received from each odor detection device 100 with the normal range of the odor type determination table 106, and identify the measurement results of each odor detection device 100 and any deteriorated odor sensors 102.

[0074] 4 is a diagram showing an example of the deterioration prediction of the odor sensor 102 and the correction process of the odor sensor 102 in the odor detection device 100. The correction process of the odor sensor 102 and the deterioration prediction of the odor sensor 102 in the odor detection device 100 will be described with reference to FIG.

[0075] Graph 401 shows characteristic data 109 of odor sensor 102D. Graph 401 is an approximate line calculated from graph 402, which was obtained through an experiment using odor sensor 102D or an odor sensor with the same characteristics (or model number) as odor sensor 102D. That is, graphs 401 and 402 show the correlation between the concentration of each odor component learned in advance and the output value of each odor sensor 102. Graph 401 shows the feature quantity (output value) output by odor sensor 102D for each concentration of a certain odor component. In addition to the reaction value obtained from the sensor, processed data obtained from the sensor can also be used as a feature quantity. For example, the slope of a waveform obtained by plotting the time elapsed since the start of measurement, the peak value, the difference from the initial value, and the like can be used as a feature quantity. In some aspects, each odor sensor 102 may have as many pieces of characteristic data 109 as the number of odor components to be detected. For example, if there are four odor sensors 102, four types of feature amounts, and four types of odor components to be detected, then there can be 64 pieces of characteristic data 109 (4*4*4).

[0076] 4, when the concentration of a certain odor is "5 ppm," odor sensor 102D is expected to output a feature amount (output value) of "d4." When the concentration of a certain odor is "5 ppm," if the actual measurement value of odor sensor 102D is "d4'," that is, if the actual measurement value of odor sensor 102D is not "d4," odor sensor 102D may be degraded.

[0077] If the amount of deterioration of odor sensor 102D (the amount of change in output value from the expected value) is equal to or less than predetermined threshold 403 or less than threshold 403, correction unit 108 determines that the amount of deterioration of odor sensor 102D is within a correctable range, and corrects the output value of odor sensor 102D. In the example of FIG. 4, threshold 403 is "d4limit" when the concentration of a certain odor is "5 ppm." When the amount of deterioration of odor sensor 102D (the amount of change in output value from the expected value) is equal to or less than predetermined threshold 403, this means that the amount of deterioration of odor sensor 102D is somewhat in line with graph 401, which shows the characteristics of odor sensor 102D, and is therefore correctable. Conversely, when the amount of deterioration of odor sensor 102D (the amount of change in output value from the expected value) is equal to or exceeds predetermined threshold 403, it indicates that the amount of deterioration of odor sensor 102D deviates significantly from graph 401 showing the characteristics of odor sensor 102D and is uncorrectable (has deteriorated to the point where it cannot be corrected).

[0078] When the amount of deterioration of odor sensor 102D is equal to or less than a predetermined threshold 403 or less than threshold 403 (when the degree of deterioration of odor sensor 102 is small), correction unit 108 corrects the output value of odor sensor 102. In the example of FIG. 4, when the concentration of a certain odor is "5 ppm" and the actual measurement value of odor sensor 102D is "d4'", the correction value (coefficient) can be, for example, "d4 / d4'=(δx+α) / d4'".

[0079] If the amount of deterioration of odor sensor 102D is equal to or exceeds predetermined threshold 403 (if the degree of deterioration of odor sensor 102 is large), correction unit 108 determines that the output value of odor sensor 102 is uncorrectable. Based on the determination that the output value of odor sensor 102 is uncorrectable, correction unit 108 outputs a signal to control unit 101 indicating that the output value of odor sensor 102 is uncorrectable or that odor sensor 102 has deteriorated.

[0080] The correction unit 108 similarly calculates correction values ​​or performs deterioration determination for the other odor sensors 102A, 102B, and 102C. In some aspects, the correction unit 108 may calculate correction values ​​or perform deterioration determination for each odor sensor 102 using graph 402 obtained through an experiment, rather than using graph 401.

[0081] In one aspect, the memory unit 104 may further store recorded data of deterioration times measured in the past for each odor sensor 102. The determination unit 107 or the correction unit 108 may then compare the actual measurement value of a certain odor sensor 102 with the recorded data of that odor sensor 102, predict the estimated time until the odor sensor 102 becomes unusable (the timing at which the actual measurement value of the odor sensor 102 will be equal to or exceed the threshold value 403), and output the prediction result to the control unit 101.

[0082] The correction unit 108 may also periodically acquire actual measurement values ​​(time-dependent data) of each odor sensor 102, calculate a regression curve from changes in the actual measurement values, and predict failure of the odor sensor 102 (calculate the estimated time until the odor sensor 102 becomes unusable) based on the regression curve. In the example of Fig. 4, the correction unit 108 predicts the time when the odor sensor 102D will become unusable (the timing when the actual measurement value of the odor sensor 102D will be equal to or exceed the threshold value 403) based on the regression curve 404 of the deterioration prediction of the odor sensor 102D.

[0083] As described above, the odor detection device 100 calculates a correction value for a deteriorated odor sensor 102 based on the characteristic data 109 of each odor sensor 102. This allows the odor detection device 100 to correct the actual measurement values ​​of odor sensors 102 with a low degree of deterioration. The odor detection device 100 can also notify the communication device 120 of information on odor sensors 102 with a high degree of deterioration. Furthermore, the odor detection device 100 calculates a regression curve for predicting deterioration from the time-series actual measurement values ​​of each odor sensor 102. This allows the odor detection device 100 to output the predicted lifespan of the odor sensor 102 to the control unit 101. In some aspects, the communication device 120 may have the functions described with reference to FIG. 4. In this case, the communication device 120 includes the correction unit 108 and the characteristic data 109 as hardware or software. Furthermore, the communication device 120 can perform correction processing for each odor sensor 102 in each odor detection device 100 and predict deterioration of the odor sensor 102 based on the actual measurement values ​​of each odor sensor 102 obtained from each of one or more odor detection devices 100.

[0084] In one aspect, the communication device 120 may receive various data from each odor sensor 102 and control the deterioration determination and correction process for each odor sensor 102 in each odor detection device 100. In this case, each odor detection device 100 transmits to the communication device 120 information such as whether the deterioration of a certain odor sensor 102 has exceeded the threshold 403, the time when the odor sensor 102 will become unusable (the timing when the actual measurement value of the odor sensor 102 will be equal to or exceed the threshold 403), etc. Based on this received information, the communication device 120 may correct the actual measurement value received from each odor detection device 100, or may send a command to each odor detection device 100 to correct the actual measurement value.

[0085] 5 is a flowchart showing an example of a processing procedure for identifying a deteriorated odor sensor 102 in the odor detection system 10. In one aspect, the control unit 101 may load a program for performing processing in the odor detection device 100 of FIG. 5 from the storage unit 104 into RAM and execute the program. In another aspect, the control unit 121 may load a program for performing processing in the communication device 120 of FIG. 5 from the storage unit 126 into RAM and execute the program. Furthermore, in another aspect, some or all of the processing may be realized as a combination of circuit elements configured to perform the processing.

[0086] The following processing will be described assuming that odor detection system 10 includes three odor detection devices 100A, 100B, and 100C, and communication device 120. Note that the following description is an example, and odor detection system 10 may include any number of odor detection devices 100. Also, it is assumed that odor detection device 100A, odor detection device 100B, and odor detection device 100C are installed in room X to detect or measure the gas concentration in room X (collectively referred to as "odor detection device 100").

[0087] In step S505, odor detection device 100 detects odor components and concentrations.

[0088] In step S510, the odor detection device 100 compares the data (normal range) in the odor classification table corresponding to the detection results (type, concentration, and level of odor component) with the sensor output (actual measured value). The odor detection device 100 may transmit the comparison results (including information on which odor sensor 102 output values ​​are within the normal range or not) to the communication device 120. In some aspects, the communication device 120 may execute the process of step S510. In this case, the communication device 120 receives the detection result data of odor components and concentrations from each odor detection device 100 in step S505.

[0089] In step S515, the communications device 120 determines whether there is an odor detection device 100 in which all of the odor sensors 102 are normal. When all of the odor sensors 102 in a certain odor detection device 100 are normal, this means that the actual measurement values ​​of all of the odor sensors 102 in that odor detection device 100 are within the normal range of any record in the odor type determination table 106. For example, if all of the actual measurement values ​​of odor sensors 102A, 102B, 102C, and 102D of odor detection device 100A are within the normal value range of record 302, then all of the odor sensors 102 in odor detection device 100A are normal.

[0090] If the communications device 120 determines that there is an odor detection device 100 in which all of the odor sensors 102 are normal (YES in step S515), the communications device 120 transfers control to step S520. Otherwise, the communications device 120 transfers control to step S530. In one aspect, the communications device 120 may receive actual measurement values ​​of the odor sensors 102 from the odor detection devices 100 and determine whether each odor sensor 102 of each odor detection device 100 is normal. In another aspect, the communications device 120 may receive data from each odor detection device 100 indicating whether each odor sensor 102 is normal.

[0091] In step S520, communications device 120 detects odor components and concentrations of odor detection devices 100 in which all odor sensors are normal. More specifically, communications device 120 uses the actual measurement data or determination results (type, concentration, and level of odor components) received from odor detection devices 100 in which all odor sensors are normal. For example, when detecting the gas concentration in room X, assume that all odor sensors 102 of odor detection device 100A are normal, but some of the odor sensors 102 of odor detection device 100B are deteriorated. In this case, communications device 120 uses the actual measurement data or determination results received from odor detection device 100A.

[0092] In step S525, communication device 120 outputs the result. In one aspect, communication device 120 may output the result to display unit 122. In another aspect, communication device 120 may transmit the result to another device via first communication unit 124 or second communication unit 125.

[0093] In step S530, the communications device 120 stores the odor sensor 102 whose output value is outside the normal range. For example, suppose that the odor component detected in step S505 by the odor detection apparatus 100 or the communications device 120 is determined to be type "X" and level "3" (corresponding to record 302). Then, suppose that the output value of the odor sensor 102D in the odor detection apparatus 100A is outside the normal range of record 302. In this case, the communications device 120 stores the odor sensor 102D in the odor detection apparatus 100A as the odor sensor 102 whose output value is outside the normal range.

[0094] In step S535, the communications device 120 determines whether or not it is possible to complement a deteriorated odor sensor 102 among multiple odor detection devices 100. Complementing an odor sensor 102 means, for example, using the odor sensor 102A of odor detection device 100B or the odor sensor 102A of odor detection device 100C instead of the deteriorated odor sensor 102A of odor detection device 100A. This determination can be made based on, for example, the distance between each of the odor detection devices 100A, 100B, and 100C, and the overlap of the inspection areas of each odor detection device 100 (whether both odor detection devices 100A and 100B have the same room as their inspection area, etc.).

[0095] If the communications device 120 determines that the deteriorated odor sensor 102 can be complemented among the multiple odor detection devices 100 (YES in step S535), the communications device 120 transfers control to step S540. Otherwise (NO in step S535), the communications device 120 transfers control to step S545.

[0096] In step S540, communication device 120 redetects the odor components and concentrations using the interpolated output values. For example, communication device 120 redetects the odor components and concentrations using the output values ​​of odor sensor 102A of odor detection device 100B instead of the output values ​​of deteriorated odor sensor 102A of odor detection device 100A.

[0097] In step S545, the communications device 120 counts the number of odor sensors 102 whose output values ​​are outside the normal range. The communications device 120 performs this count for each odor detection device 100. For example, suppose that odor sensor 102A of odor detection device 100A has deteriorated. Furthermore, suppose that odor sensors 102A and 102B of odor detection device 100B have deteriorated. In this case, the count for odor detection device 100A becomes "1," and the count for odor detection device 100B becomes "2."

[0098] In step S550, the communications device 120 determines whether or not the proportion of odor sensors whose output values ​​are outside the normal range is half or more of all the odor sensors in each odor detection device 100. For example, odor detection device 100A includes four odor sensors 102A, 102B, 102C, and 102D. Suppose that the output values ​​of odor sensors 102A and 102B are outside the normal range. In this case, half of all the odor sensors in odor detection device 100A have output values ​​outside the normal range.

[0099] If communications device 120 determines that, for each odor detection apparatus 100, half or more of all odor sensors have output values ​​outside the normal range (YES in step S550), it proceeds to step S555. Otherwise (NO in step S550), communications device 120 proceeds to step S560.

[0100] In step S555, communication device 120 outputs a determination error. This determination error is performed for each odor detection device 100. For example, if more than half of all odor sensors in both odor detection devices 100A and 100B have output values ​​outside the normal range, communication device 120 outputs a determination error for odor detection device 100A and a determination error for odor detection device 100B.

[0101] In one aspect, communication device 120 may output the determination error to display unit 122, or may transmit the determination error to another device via first communication unit 124. In another aspect, each odor detection device 100 may output the determination error to communication device 120. In this case, communication device 120 outputs the received determination error to display unit 122 or first communication unit 124.

[0102] In step S560, communications device 120 calculates a correction coefficient for the deteriorated odor sensor for each odor detection device 100. Communications device 120 calculates the correction coefficient using the procedure described with reference to FIG. 4. In some aspects, odor detection device 100 may calculate the correction coefficient for the odor sensor. In this case, odor detection device 100 transmits the corrected output value to communications device 120.

[0103] In step S565, the communications device 120 determines whether the deterioration of the odor sensor 102 has reached the correction limit value for each odor detection device 100. If the communications device 120 determines that the deterioration of the odor sensor 102 has reached the correction limit value (YES in step S565), it transfers control to step S555. If not (NO in step S565), the communications device 120 transfers control to step S570.

[0104] In step S570, odor detection apparatus 100 multiplies the output value to be corrected received from odor detection apparatus 100 by the correction coefficient calculated in step S560. In one aspect, odor detection apparatus 100 may transmit the corrected output value to communication device 120.

[0105] In some cases, when the processes of steps S535 and S540 (correction processes between multiple odor detection devices 100) are not required, all of the processes in FIG. 5 may be performed by odor detection device 100 alone.

[0106] In another aspect, the odor detection device 100 may have both or either a function to independently execute the processing of FIG. 5 except for the processing of steps S535 and S540, and a function to execute the processing of FIG. 5 in cooperation with the communication device 120 and other odor detection devices 100.

[0107] 5 except for steps S535 and S540 may be executed by either the communications device 120 or the odor detection device 100. When each process is executed on the communications device 120 side, various correction processes and determination processes may be executed on the actual measurement values ​​obtained from each odor detection device 100. When each process is executed on the odor detection device 100 side, the odor detection device 100 may execute various correction processes and determination processes on the actual measurement values ​​thereof, and output the results of each process (e.g., corrected output values, deterioration determination results of the odor sensor 102) to the communications device 120 together with the actual measurement values ​​of the odor components.

[0108] As described above, the odor detection system 10 or odor detection device 100 according to the present embodiment compares the normal range of each odor sensor 102 contained in the odor type determination table 106 with the actual measurement value of each odor sensor 102. Then, if the actual measurement values ​​of the majority of odor sensors 102 are within the normal range, the odor detection system 10 or odor detection device 100 can determine that the odor sensors 102 whose actual measurement values ​​are not within the normal range are degraded.

[0109] In addition, in a certain aspect, when the degree of deterioration of the odor sensor 102 is small, the odor detection system 10 or the odor detection device 100 can suppress the influence of the deterioration of the odor sensor 102 by multiplying the actual measurement value by a complementary coefficient.

[0110] In another aspect, the odor detection system 10 or the odor detection device 100 can predict when the odor sensor 102 will fail based on the degree of deterioration of the odor sensor 102.

[0111] In another aspect, when the odor sensor 102 of one odor detection device 100 deteriorates, the odor detection system 10 can complement the deteriorated odor sensor 102 of the odor detection device 100 by using the odor sensor 102 of another odor detection device 100.

[0112] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope equivalent to the claims. Furthermore, the disclosures described in the embodiments and each modification are intended to be implemented, as far as possible, either alone or in combination. [Explanation of symbols]

[0113] 10 Odor detection system, 100 Odor detection device, 101, 121 Control unit, 102A, 102B, 102C, 102D Odor sensor, 104, 126 Memory unit, 105 Identification unit, 106 Odor type discrimination table, 107 Judgment unit, 108 Correction unit, 109 Characteristic data, 110 Operation switch, 111 Battery, 112 Communication unit, 113 Internal bus, 120 Communication device, 122 Display unit, 123 Operation unit, 124 First communication unit, 125 Second communication unit, 127 Speaker, 128 Microphone, 301 Gas to be measured, 302 Record, 401, 402 Graph, 403 Threshold, 404 Regression curve.

Claims

1. Three or more odor sensors; a memory unit for storing normal range data obtained by learning the normal range of the output value of each odor sensor for each odor component; a determination unit that determines the deterioration of each of the plurality of odor sensors, The determination unit comparing the output values ​​of each of the plurality of odor sensors with the normal range data; The odor detection device determines that the minority of the odor sensors have deteriorated when a majority of the plurality of odor sensors output actual measurement values ​​within the normal range and the remaining minority of the odor sensors output actual measurement values ​​outside the normal range.

2. 2. The odor detection device of claim 1, wherein the determination unit determines that the odor components detected by the plurality of odor sensors are indistinguishable based on the fact that no odor components are found in the normal range data whose actual measurement values ​​of the majority of odor sensors are within the normal range.

3. The device further includes a correction unit that corrects the actual measurement value of the deteriorated odor sensor, The correction unit The actual measured value of a certain odor sensor is compared with an approximate line of the correlation between the concentration of each odor component learned in advance and the output value of the certain odor sensor, An odor detection device as described in claim 1 or 2, which corrects the actual measured value of a certain odor sensor to approach the output value indicated by the approximation line based on the difference between the actual measured value and the output value indicated by the approximation line being within a predetermined threshold value.

4. The odor detection device of claim 3, wherein the judgment unit outputs a judgment result indicating that the certain odor sensor has deteriorated based on the difference between the actual measured value of the certain odor sensor and the output value indicated by the approximation line exceeding a predetermined threshold value.

5. The odor detection device according to claim 4 , wherein the determination unit outputs an estimated time until the certain odor sensor becomes unusable from a regression curve obtained from time-dependent data of actual measured values ​​of the certain odor sensor.

6. The storage unit further stores recorded data of deterioration times of the odor sensor measured in the past, The odor detection device according to claim 4 , wherein the determination unit compares the actual measurement value of the certain odor sensor with the recorded data, and outputs an estimated time until the certain odor sensor becomes unusable.

7. An odor detection system, comprising: A plurality of odor detection devices; a communication device; Each of the plurality of odor detection devices includes: Three or more odor sensors; a memory unit for storing normal range data obtained by learning the normal range of the output value of each odor sensor for each odor component; a determination unit that determines the deterioration of each of the plurality of odor sensors, The determination unit comparing the output values ​​of each of the plurality of odor sensors with the normal range data; If a majority of the plurality of odor sensors output actual measurement values ​​within a normal range and the remaining minority of odor sensors output actual measurement values ​​outside the normal range, the minority of odor sensors are determined to be deteriorated; The communication device a communication unit for communicating with each of the plurality of odor detection devices; an odor detection system comprising a display unit capable of displaying the results of deterioration determination obtained from each of the plurality of odor detection devices;

8. 8. The odor detection system of claim 7, wherein the determination unit determines that the odor components detected by the plurality of odor sensors are indistinguishable based on the fact that no odor components are found in the normal range data whose actual measurement values ​​of the majority of odor sensors are within the normal range.

9. The odor detection device further includes a correction unit that corrects the actual measurement value of a deteriorated odor sensor, The correction unit The actual measured value of a certain odor sensor is compared with an approximate line of the correlation between the concentration of each odor component learned in advance and the output value of the certain odor sensor, The odor detection system of claim 7 or 8, wherein the actual measured value of the odor sensor is corrected to approach the output value indicated by the approximation line based on the difference between the actual measured value and the output value indicated by the approximation line being within a predetermined threshold.

10. The odor detection system of claim 9, wherein the determination unit transmits a determination result indicating that the certain odor sensor has deteriorated to the communication device based on the difference between the actual measured value of the certain odor sensor and the output value indicated by the approximation line exceeding a predetermined threshold.

11. The odor detection system according to claim 10 , wherein the determination unit transmits to the communication device an estimated time until the certain odor sensor becomes unusable, based on a regression curve obtained from time-dependent data of actual measured values ​​of the certain odor sensor.

12. The storage unit further stores recorded data of deterioration times of the odor sensor measured in the past, The odor detection system according to claim 10 , wherein the determination unit compares the actual measurement value of the certain odor sensor with the recorded data, and transmits to the communication device an estimated time until the certain odor sensor becomes unusable.

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