In-vehicle abnormality detection device and in-vehicle abnormality detection method

Abstract

The present invention can easily and accurately detect the presence of organisms in a vehicle. To this end, the rate of change of the carbon dioxide concentration in the vehicle at an arbitrary time point in the parking state is estimated based on the detection signal of the CO2 concentration sensor at two different time points in the parking state, and the carbon dioxide concentration in the vehicle at a time point after a predetermined time corresponding to the time constant has passed since the arbitrary time point is estimated based on the detection signal of the CO2 concentration sensor at the arbitrary time point, the pre-set time constant of the concentration change of the carbon dioxide concentration in the vehicle, and the estimated rate of change (steps S4 to S7). When the estimated carbon dioxide concentration in the vehicle is above the threshold value set according to the organism to be detected, it is determined that the organism to be detected exists in the vehicle (steps S8 and S9).

Description

Technical Field

[0001] This invention relates to a vehicle interior anomaly detection device and a vehicle interior anomaly detection method. Background Art

[0002] As a device for detecting the presence of living organisms such as humans or animals inside a vehicle, methods have been proposed for detecting the carbon dioxide concentration (hereinafter also referred to as CO2 concentration) inside the vehicle, and methods for detecting the presence of living organisms by using millimeter-wave radar to detect movements based on heartbeats or breathing.

[0003] As a method for detecting living organisms using CO2 concentration, for example, a method has been proposed to determine the presence of living organisms when the CO2 concentration or CO2 increase rate inside a vehicle exceeds a threshold (e.g., see Patent Document 1). Additionally, methods for detecting the number of people in a vehicle based on CO2 concentration have been proposed (e.g., see Patent Document 2), and devices for detecting forgotten children based on CO2 concentration have been proposed (e.g., see Non-Patent Document 1), etc.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: U.S. Patent No. 20160103111

[0007] Patent Document 2: US Patent No. 20140278145

[0008] Non-patent literature

[0009] Non-Patent Document 1: PAYTON'S CHARM, Internet, URL<https: / / paytonscharm.com / > Summary of the Invention

[0010] Problems to be solved by the invention

[0011] Methods for determining the presence of living organisms in a vehicle by detecting when the CO2 concentration or rate of increase exceeds a threshold require pre-setting the threshold, such as through actual CO2 concentration measurements. However, in reality, it takes time for the CO2 concentration to reach a value equivalent to the threshold, and individual differences are significant. Therefore, when considering individual differences to set an appropriate threshold, it is necessary to actually measure CO2 concentrations for multiple individuals and set one or more thresholds corresponding to these individuals based on the multiple measurement results. This time-consuming process is particularly challenging when setting thresholds to detect the presence of children or infants, as it requires placing them in an environment equivalent to being actually confined in a vehicle for extended periods, making it difficult to measure CO2 concentrations over such long periods.

[0012] Furthermore, the CO2 concentration inside a vehicle varies not only due to the amount of CO2 emitted by children and infants present inside, but also due to the vehicle's airtightness, which deteriorates over time. Therefore, a detection method capable of more accurately detecting the presence of children inside a vehicle is desired.

[0013] Therefore, the present invention was made in view of the above-mentioned unresolved problems, and aims to provide an in-vehicle anomaly detection device and method that can detect the presence of living organisms in a vehicle with higher accuracy.

[0014] Solutions for solving problems

[0015] An in-vehicle abnormality detection device according to one embodiment of the present invention comprises: a CO2 concentration sensor for detecting the carbon dioxide concentration in the vehicle; a parking state detection unit for detecting that the vehicle is in the parking state; a time constant storage unit for storing a time constant τ for a concentration change of the carbon dioxide concentration in the vehicle; and a rate of change estimation unit for estimating the carbon dioxide concentration in the vehicle at time t when the parking state is detected based on detection signals C(t1) and C(t2) from the CO2 concentration sensor at two different time points t1 and t2 when the parking state is detected by the parking state detection unit. a carbon dioxide concentration estimating unit that estimates an estimated carbon dioxide concentration value C0 in the vehicle at a time point after a predetermined time has elapsed from time point t based on the detection signal C(t) of the CO2 concentration sensor at time point t, the time constant τ stored in the time constant storage unit, and the rate of change estimated by the rate of change estimating unit; and an abnormality determining unit that determines that the target organism is present in the vehicle when the estimated carbon dioxide concentration value C0 estimated by the carbon dioxide concentration estimating unit is greater than or equal to a threshold value set based on the target organism. Hereinafter, when a time point t and a symbol representing a similar time point are used together with an operator, the t and the symbol represent the moment of the time point.

[0016] In addition, another embodiment of the present invention relates to a vehicle interior anomaly detection method that performs the following processing: detecting the carbon dioxide concentration inside the vehicle when it is in a parked state using a CO2 concentration sensor; estimating the rate of change of the carbon dioxide concentration inside the vehicle at any time point when it is in a parked state based on the detection signals of the CO2 concentration sensor at two different time points when it is in a parked state; estimating the carbon dioxide concentration inside the vehicle at a time point after a predetermined time corresponding to the time constant has elapsed from the arbitrary time point based on the detection signal of the CO2 concentration sensor at the arbitrary time point, the time constant of the concentration change of the carbon dioxide concentration inside the vehicle, and the estimated rate of change; and determining that a biological entity, which is the target of detection, is present in the vehicle when the estimated carbon dioxide concentration inside the vehicle is above a threshold set according to the biological entity being detected.

[0017] Furthermore, another embodiment of the present invention relates to an in-vehicle anomaly detection device comprising: a CO2 concentration sensor that detects the carbon dioxide concentration inside the vehicle; a parking state detection unit that detects a parking state; a time constant storage unit that stores the time constant τ of the concentration change of the carbon dioxide concentration inside the vehicle; and a rate of change estimation unit that estimates the time point at which the parking state is detected based on the detection signals C(t1) and C(t2) of the CO2 concentration sensor at two different time points t1 and t2 (where t2>t1) when the parking state is detected by the parking state detection unit. The system includes: a rate of change of carbon dioxide concentration inside the vehicle, dC(t) / dt; a threshold determination unit, which determines a threshold Vth based on the detection signal C(t3) of the CO2 concentration sensor at time point t3 when the vehicle is in a parked state, the time constant τ stored in the time constant storage unit, and the CO2 concentration Coutdoor outside the vehicle; and an anomaly determination unit, which determines whether there is a biological entity inside the vehicle that is the target of detection based on the comparison between the rate of change of carbon dioxide concentration estimated by the rate of change estimation unit and the threshold Vth determined by the threshold determination unit.

[0018] Furthermore, another embodiment of the present invention relates to a vehicle interior anomaly detection method that performs the following processing: detecting the carbon dioxide concentration inside the vehicle when it is in a parked state using a CO2 concentration sensor; estimating the rate of change of the carbon dioxide concentration inside the vehicle at any time point when it is in a parked state based on the detection signals of the CO2 concentration sensor at two different time points; determining a threshold Vth for the rate of change of the carbon dioxide concentration inside the vehicle based on the detection signals of the CO2 concentration sensor at the arbitrary time point, the time constant of the concentration change of the carbon dioxide concentration inside the vehicle, and the CO2 concentration outside the vehicle (Coutdoor); and comparing the estimated rate of change of the carbon dioxide concentration inside the vehicle with the threshold Vth to determine whether there is a biological entity inside the vehicle that is the target of detection.

[0019] Effects of the Invention

[0020] According to one aspect of the present invention, the presence of living organisms inside a vehicle can be detected with higher precision. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic configuration diagram showing an example of the vehicle interior abnormality detection device according to the first embodiment of the present invention.

[0022] Figure 2 This is a layout diagram showing an example of the layout position of the CO2 concentration sensor.

[0023] Figure 3 This is a flowchart illustrating an example of the decision-making process.

[0024] Figure 4 This is a chart illustrating an example of changes in carbon dioxide concentration.

[0025] Figure 5 This is a schematic configuration diagram showing an example of a vehicle interior abnormality detection device according to a second embodiment of the present invention.

[0026] Figure 6 It is a schematic configuration diagram showing a modified example of the vehicle interior abnormality detection device according to the second embodiment.

[0027] Figure 7 This is a flowchart illustrating an example of the decision-making process involved in the second embodiment.

[0028] Figure 8 This is a flowchart showing a modified example of the determination process according to the second embodiment. DETAILED DESCRIPTION

[0029] Next, embodiments of the present invention will be described with reference to the accompanying drawings. In the following drawings, identical or similar parts are denoted by the same or similar symbols. Furthermore, the embodiments shown below exemplify apparatus and methods for embodying the technical concept of the present invention; the technical concept of the present invention does not specify the construction, arrangement, etc., of structural components as described below. The technical concept of the present invention can be modified in various ways within the scope of protection defined by the claims.

[0030] <First Implementation Method>

[0031] <Structure of In-Vehicle Anomaly Detection Device 1>

[0032] Figure 1 This is a schematic structural diagram illustrating an example of an in-vehicle anomaly detection device according to the first embodiment of the present invention.

[0033] The in-vehicle anomaly detection device 1 includes: a CO2 concentration sensor 2 that detects the concentration of carbon dioxide; an engine off detection unit 3 that detects when the engine is off; a driver detection unit 4 that detects when there is no driver in the vehicle; a door status detection unit 5 that detects when all doors of the vehicle are closed; an anomaly determination unit 6 that estimates the carbon dioxide concentration C0 in the vehicle under the assumption of a stable state (hereinafter also referred to as the CO2 concentration estimate C0) based on the detection signals from these units, and detects the presence of living organisms in the vehicle based on the estimated CO2 concentration estimate C0; and a notification unit 7 that notifies of the presence of living organisms when the anomaly determination unit 6 detects them in the vehicle.

[0034] CO2 concentration sensor 2 can, as Figure 2 As shown in 2a, it is positioned immediately behind the air intake (not shown) located at the bottom of the vehicle body. With this placement near the air intake, an external air fan is activated to draw in outside air, causing the detection signal from CO2 concentration sensor 2 to become equivalent to the CO2 concentration of the outside air. Therefore, by using a detection signal equivalent to the CO2 concentration of the outside air to correct the time constant τ (described later), the accuracy of the CO2 concentration estimate C0 can be improved.

[0035] Alternatively, CO2 concentration sensor 2 can be used as follows: Figure 2 As shown in 2b, it is positioned near the vent on the upper part of the instrument panel. In this case, the estimation accuracy of the CO2 concentration estimate C0 can also be improved by using the detection signal of the CO2 concentration sensor 2 when the external air fan is running to allow outside air to enter.

[0036] CO2 concentration sensor 2 can also be used as... Figure 2As shown in 2c, it is positioned near the vehicle floor. In warm vehicle conditions, due to the relationship between the vehicle's interior temperature and the temperature of exhaled breath, exhaled breath may accumulate in the lower part of the vehicle. By placing the CO2 concentration sensor 2 near the vehicle floor, changes in CO2 concentration caused by exhaled breath can be quickly detected.

[0037] Alternatively, the CO2 concentration sensor 2 may be used as Figure 2 As shown in Figure 2d, it is installed in the car's ceiling. In cold conditions inside the car, due to the relationship between the car's interior temperature and the temperature of exhaled breath, exhaled breath may accumulate at the top of the car. By installing the CO2 concentration sensor 2 in the car's ceiling, changes in the CO2 concentration caused by exhaled breath can be quickly detected.

[0038] In addition, the CO2 concentration sensor 2 can also be used as Figure 2 As shown in 2e, it is positioned in the center of the vehicle interior, that is, roughly in the center in both the front-to-back and left-to-right directions. By positioning it in the roughly center of the vehicle interior, the presence of a creature can be detected in the same amount of time, regardless of its location within the vehicle.

[0039] Alternatively, the CO2 concentration sensor 2 can be configured at any of the multiple locations 2a to 2e, and the CO2 concentration inside the vehicle can be estimated based on the detection signals from the multiple CO2 concentration sensors 2. The estimated CO2 concentration is then used to perform the decision processing described later. In this way, by using the detection signals from multiple CO2 concentration sensors 2 configured at different locations inside the vehicle, changes in CO2 concentration caused by the exhalation of living organisms present in the vehicle can be detected with higher accuracy and faster speed.

[0040] Alternatively, the circulating fan can be set to operate with the CO2 concentration sensor 2 positioned at each of the positions 2a to 2e. By operating the circulating fan to mix the air inside the vehicle, deviations in CO2 concentration caused by the placement of the CO2 concentration sensor 2 and the buoyancy of CO2 can be suppressed.

[0041] The engine shutdown detection unit 3 is a sensor that detects when the engine is stopped. For example, when it detects that "LOCK" is selected in the ignition switch, it determines that the engine is stopped.

[0042] The driver detection unit 4 is a sensor that detects whether the driver is seated in the driver's seat. For example, a pressure sensor is installed in the driver's seat, and the driver's seat status is detected based on the pressure sensor's reading.

[0043] The door status detection unit 5 is a sensor that detects whether all doors of the vehicle are closed. For example, it can be detected by installing a switch on each door that is turned on when the door is closed. In the case of a vehicle with a rear door, it detects whether all doors, including the rear door, are closed.

[0044] The abnormality determination unit 6 receives detection signals from the engine shutdown detection unit 3, the driver detection unit 4, and the door state detection unit 5. When the engine is off, the driver is not in the driver's seat, and all doors are closed (i.e., when the vehicle is determined to be parked), it detects the presence of a living organism inside the vehicle. Specifically, the abnormality determination unit 6 estimates a CO2 concentration estimate C0 based on the detection signal from the CO2 concentration sensor 2 and the time constant τ pre-stored in the time constant storage unit 6a. Based on the estimated CO2 concentration estimate C0, the following equation (1) is used to estimate the CO2 concentration estimate C0 based on the detection signal from the CO2 concentration sensor 2 at the current time point t. In equation (1), t1 and t2 represent two different time points when the vehicle is determined to be parked, with time point t2 representing a time point later than time point t1. Furthermore, C(t1) represents the detection signal from the CO2 concentration sensor 2 detected at time point t1, and C(t2) represents the detection signal from the CO2 concentration sensor 2 detected at time point t2.

[0045] C0=C(t)+τ×dC(t) / dt

[0046] dC(t) / dt

[0047] =[C(t2)-C(t1)] / (t2-t1)......(1)

[0048] Furthermore, the time constant τ is determined by the volume and airtightness of the vehicle interior and represents the time constant for changes in the carbon dioxide concentration within the vehicle. The time constant τ is set in advance through experiments, etc., and stored in the time constant storage unit 6a. The time constant τ is updated based on the detection signal from the CO2 concentration sensor 2 during the execution of the determination process described later. dC(t) / dt represents the change per unit time of the CO2 concentration detection signal C(t) at time point t. In equation (1), the rate of change of the CO2 concentration detection signal C(t) per unit time at any time point t while the vehicle is parked is calculated based on the detection signals C(t1) and C(t2) from the CO2 concentration sensor 2 at time points t1 and t2 while the vehicle is parked (rate of change estimation unit).

[0049] Furthermore, when the abnormality determination unit 6 determines that a living being exists in the vehicle, the abnormality determination unit 6 activates the notification unit 7 to notify the vehicle of the presence of a living being.

[0050] The abnormality determination unit 6 causes the notification unit 7 to operate. Examples of the operation include the notification unit 7 sounding an alarm, the notification unit 7 honking the vehicle's horn, the notification unit 7 contacting the driver via an email or SNS (Social Networking Service) notification sent to the driver's mobile phone or smartphone, and the notification unit 7 notifying the driver via the vehicle's own wireless or Internet connection service.

[0051] In addition, the abnormality determination unit 6 can also be configured to not only operate the notification unit 7 but also open the vehicle's windows to allow outside air to enter when it is determined that a living creature exists in the vehicle. It can also be configured not to provide the notification unit 7, but to open the vehicle's windows or operate the cooling and heating functions when it is determined that a living creature exists in the vehicle.

[0052] <Abnormality Detection Unit 6 Detection and Processing>

[0053] Then, accompanied by Figure 3 The flowchart below illustrates an example of the processing procedure performed by the exception determination unit 6.

[0054] In the anomaly determination unit 6, determination processing is performed at a pre-set predetermined cycle. First, the detection signals from the engine off detection unit 3, the driver detection unit 4, and the door status detection unit 5 are input (step S1). Then, if the engine is not detected to be off, the driver is not in the driver's seat, and all doors are closed (step S2), the processing ends directly. When all conditions are met, the vehicle is considered to be in a parking state, and the process proceeds to step S3 (parking state detection unit). After determining that the vehicle is in a parking state, the time point after a 5-second waiting period is set as t=0, and the detection signal from the CO2 concentration sensor 2 at time point t=0 is read as C(0) (step S4). The waiting time in step S3 (5 seconds in this case) is the time used to measure the CO2 concentration inside the vehicle when the vehicle is parked with all doors closed, that is, the initial value of the CO2 concentration inside the vehicle. It is set to a time when the changes in the CO2 concentration inside the vehicle are stable and an appropriate value can be obtained as the initial value for determination processing, which is accompanied by the opening and closing of parking doors, the stopping of the circulating fan, and the exit of passengers.

[0055] Next, proceed to step S5. After a 30-second waiting period from time t=0, proceed to step S6 to read the detection signal C (30s) from CO2 concentration sensor 2. The waiting time in step S5 (30 seconds in this case) is set to determine the presence of a living being in the vehicle, even with all doors closed, based on the increase in CO2 concentration after parking. Here, for example, if the living being to be detected is a child, pet, etc., it is set to approximately 30 seconds.

[0056] Next, proceed to step S7, and estimate the CO2 concentration C0 (carbon dioxide concentration estimation part) according to the above formula (1) and the following formula (2).

[0057] C0

[0058] =C(30s)+{C(30s)+C(0)}×τ / (30s) ......(2)

[0060] Here, the CO2 concentration inside the vehicle varies depending on the amount of CO2 emitted by the organisms, but also varies depending on the airtightness and volume of the vehicle. Therefore, in the first embodiment, as shown in equation (2), the CO2 concentration estimate C0 is estimated by taking into account the time constant τ determined by the airtightness and volume of the vehicle.

[0061] If the estimated CO2 concentration C0 is calculated according to equation (2), the process proceeds to step S8, where the estimated CO2 concentration C0 is compared with a preset threshold of 3000 ppm. If the estimated CO2 concentration C0 is above the threshold (C0 ≥ 3000 ppm), it is determined that a living organism is present in the vehicle, and the notification unit 7 is activated to notify the vehicle of the presence of a living organism (step S9) (abnormality determination unit). On the other hand, if the estimated CO2 concentration C0 is less than the threshold of 3000 ppm (C0 < 3000 ppm), the process proceeds to step S10. Here, we assume that the living organism being detected is a child, pet, etc., and the threshold is set to 3000 ppm.

[0062] The detection signal C(90s) of the CO2 concentration sensor 2 is read at a time point when a waiting time of 60s has passed since the CO2 concentration estimated value C0 was estimated in step S7 in step S10, that is, at a time point when 90 seconds have passed since time t=0 (step S11).

[0063] The waiting time 60 seconds in step S10 is set based on the estimation interval of the CO2 concentration estimated value C0. Here, for example, the CO2 concentration estimated value C0 is estimated at intervals of 60 seconds, and the waiting time is set to approximately 60 seconds.

[0064] Next, the process moves to step S12, and according to the above-mentioned formula (1), the CO2 concentration estimated value C0 is estimated according to the following formula (3).

[0065] C0

[0066] =C(90s)+{C(90s)-C(0)}×τ / (90s) ......(3)

[0068] Then, the estimated CO2 concentration C0 calculated according to equation (3) is compared with a preset threshold of 3000 ppm. If the estimated CO2 concentration C0 is above the threshold of 3000 ppm (C0 ≥ 3000 ppm) (step S13), it is determined that a biological entity is present in the vehicle and the notification unit 7 is activated to notify that a biological entity is present in the vehicle (step S14). On the other hand, if the estimated CO2 concentration C0 is less than the threshold of 3000 ppm (C0 < 3000 ppm), the process proceeds to step S15.

[0069] The threshold of 3000 ppm is a value previously determined through experiments and is set to a CO2 concentration that indicates the presence of a target organism in the vehicle when all doors are closed. For example, when detecting the presence of a child in a vehicle, the threshold is set to approximately 3000 ppm.

[0070] Furthermore, in steps S7 and S12, a threshold value (3000 ppm) is set to detect the presence of a child in the vehicle, but this is not a limitation. For example, multiple thresholds can be set not only for children but also for infants, adults, etc., depending on the type of organism being detected. Each of these multiple thresholds is compared with the estimated CO2 concentration C0 at two different points: one after a 30-second wait from the time the vehicle was determined to be parked, and another after a 90-second wait from the time the vehicle was determined to be parked. By setting multiple thresholds and comparing them with the estimated CO2 concentration C0, the type of organism present in the vehicle, such as an adult or a child, can be detected based on the magnitude of the threshold at which the estimated CO2 concentration C0 exceeds the threshold value.

[0071] Here, if a living being is present in the vehicle with all doors closed, the CO2 concentration inside the vehicle rises. Therefore, the presence of a living being can be detected based on the change in CO2 concentration. For example, if the estimated CO2 concentration value C0 inside the vehicle, estimated in step S7, exceeds a threshold, notification of the presence of a living being is made at that time. On the other hand, if the estimated CO2 concentration value C0 estimated in step S7 is less than the threshold despite the presence of a living being, notification of the presence of a living being is not made at that time. However, as time passes, the CO2 concentration inside the vehicle rises due to the exhalation of the living being. Therefore, notification of the presence of a living being is made at the time when the estimated CO2 concentration value C0 exceeds the threshold in step S12.

[0072] Thus, by estimating the CO2 concentration C0 twice—at time points 30 seconds after t=0 and 90 seconds after t=0—and comparing it with the threshold, the presence of life can be detected more reliably.

[0073] Furthermore, this is set to compare the estimated CO2 concentration C0 with the threshold twice, but it is not limited to two times and can be set to three or more times. In addition, the comparison of the estimated CO2 concentration C0 with the threshold is not limited to a 60-second interval and can be performed at any interval.

[0074] In step S15, when the waiting time of 210 seconds has elapsed since the estimated CO2 concentration value C0 was estimated in step S12, the process proceeds to step S16, where the detection signal C (300 s) of the CO2 concentration sensor 2 is read. Next, when the waiting time of 1 hour has elapsed since the detection signal C (300 s) of the CO2 concentration sensor 2 was read in step S16 (step S17), the process proceeds to step S18, where the detection signal C (1 hour) of the CO2 concentration sensor 2 at the time when the waiting time of 1 hour has elapsed since the detection signal C (300 s) of the CO2 concentration sensor 2 was read in step S16 is read.

[0075] Next, at the point in time where 300 seconds have elapsed since the detection signal C(1 hour) of CO2 concentration sensor 2 was read in step S18 (step S19), the detection signal C(1h+300s) of CO2 concentration sensor 2 is read in (step S20).

[0076] Then, proceed to step S21, where the time constant τ (time constant update unit) is updated using the following equation (4) based on the detection signal C(0) of CO2 concentration sensor 2 detected in step S4, the detection signal C(300s) of CO2 concentration sensor 2 detected in step S16, the detection signal C(1hour) of CO2 concentration sensor 2 detected in step S18, and the detection signal C(1h+300s) of CO2 concentration sensor 2 detected in step S20. The updated time constant τ is then stored in the time constant storage unit 6a. Finally, the process ends.

[0077] x

[0078] ={C(300s)-C(0)] / {C(1h+300s)-C(1h)}

[0079] τ = 1 hour / In (×)

[0080] τnew=τ×0.01+τo|d×0.99 ......(4)

[0082] In other words, in steps S15 to S21, the time constant τ is updated. Specifically, it is updated based on the change in CO2 concentration inside the vehicle from time t=0 to 300 seconds (5 minutes), "C(300s)-C(0)", and the change in CO2 concentration inside the vehicle from one hour after the calculation of this change to five minutes later, "C(1h+300s)-C(1h)". Furthermore, while the time constant τ is updated based on the change in CO2 concentration inside the vehicle within 5 minutes and the change within 5 minutes after one hour, the change in CO2 concentration is not limited to 5 minutes; it can be any time during which the CO2 concentration changes sufficiently. Additionally, the interval for calculating the change in CO2 concentration inside the vehicle is not limited to one hour; it can be set to a range where the CO2 concentration does not change.

[0083] Here, at the time point of step S15, it is determined that there are no living organisms inside the vehicle. Therefore, the change in CO2 concentration inside the vehicle is not affected by CO2 emitted by living organisms, and can be considered as a change caused by the airtightness of the vehicle. Therefore, by setting the time constant τ based on the detection signal of CO2 concentration sensor 2 when it is determined that there are no living organisms inside the vehicle, a time constant τ that takes into account the airtightness of the vehicle at the current time point can be obtained.

[0084] In addition, Figure 3In the flowchart, after detecting in step S2 that the engine is off, the driver is not in the driver's seat, and all doors are closed, thus determining that the vehicle is in a parked state, the process ends when the conditions of step S2 are no longer met, i.e., when the engine is running, the driver is in the driver's seat, or any door is open. Figure 3 processing.

[0085] <Effects of the in-vehicle anomaly detection device 1 according to the first embodiment>

[0086] In the first embodiment, the estimated CO2 concentration C0 is used as the CO2 concentration inside the vehicle. However, conventionally, a method for detecting the CO2 concentration inside a vehicle has been proposed that uses the following formula (5) for calculation.

[0087] Ccabin(t)

[0088] =C0+[Ccabin(t=0)-C0]×e -t / τ

[0089] C0=Coutdoor+CHILDrate×τ......(5)

[0090] Furthermore, in equation (5), Ccabin is the CO2 concentration inside the vehicle, and τ is a time constant. CHILDrate is the CO2 increase rate, which is the value obtained by dividing the CO2 emission of infants and children present in the vehicle by the vehicle's volume. For example, in the case of a 10kg infant in a relatively large truck, CHILDrate is approximately 20ppm / min. Coutdoor is the CO2 concentration outside the vehicle. Regarding Coutdoor, for example, it can be set as a fixed value of 500ppm, or, if CO2 concentration sensor 2 is positioned near the vehicle's air intake, it can also be measured by allowing outside air to enter through ventilation.

[0091] Figure 4 This graph shows the CO2 increase rate of infants, children, and dogs inside a relatively large truck. The horizontal axis represents elapsed time (min), and the vertical axis represents the CO2 concentration inside the vehicle (ppm). The CO2 increase rate for infants (characteristic line L3) weighing approximately 10 kg was 19 ppm / min. The CO2 increase rate for children (characteristic line L2) weighing 21 kg was 36 ppm / min. The CO2 increase rate for dogs (characteristic line L1) weighing 40 kg was 42 ppm / min. Furthermore, with two adult males present in the vehicle, the CO2 increase rate was 187 ppm / min.

[0092] like Figure 4 As shown, the CO2 increase rate varies depending on the infant, child, and dog, and also varies based on weight, number of people, etc. Therefore, when using the above formula (5) to detect the CO2 concentration inside the vehicle, it is necessary to measure the CO2 increase rate equivalent to CHILDrate for each biological being tested, such as infants, children, and dogs. In addition, to improve the accuracy of CHILDrate, individual differences also need to be considered, which requires considerable effort. Furthermore, since the CO2 concentration outside the vehicle varies depending on the environment in which the vehicle is placed, it is desirable to actually measure the CO2 concentration outside the vehicle in order to improve the detection accuracy of biological beings present inside the vehicle, which also requires considerable effort.

[0093] In contrast, in the in-vehicle anomaly detection device 1 of the first embodiment, the estimated CO2 concentration C0 inside the vehicle is estimated according to the formula (1). All terms except the time constant τ are values ​​detected by the CO2 concentration sensor 2 after the point at which the vehicle is determined to be in a parked state; that is, values ​​reflecting the CO2 concentration at the detected point in time. Then, in the determination process, whenever it is determined that no living organisms are present inside the vehicle, the time constant τ is updated only based on the value detected by the CO2 concentration sensor 2. Therefore, the time constant τ is a value reflecting vehicle characteristics such as airtightness at the updated point in time. As a result, by estimating the CO2 concentration C0 based on the time constant τ corresponding to vehicle characteristics such as airtightness at the current point in time and the CO2 concentration at the current point in time, the CO2 concentration inside the vehicle under the assumption of a stable state can be calculated with higher accuracy, thereby improving the accuracy of determining whether living organisms are present inside the vehicle.

[0094] In addition, as described above, the time constant τ is updated using the detection value of the CO2 concentration sensor 2 after the time point when it is determined that there is no living organism in the vehicle in the judgment process. Therefore, there is no need to obtain information for updating the time constant τ separately, and the update can be easily performed.

[0095] Furthermore, if the presence of life in a vehicle is determined by comparing the CO2 concentration inside the vehicle with a threshold or by comparing the rate of increase of the CO2 concentration inside the vehicle with a threshold, when the vehicle is parked with a relatively high CO2 concentration, it may be incorrectly determined that life is present even if there is no life in the vehicle and the CO2 concentration is higher than the threshold. In addition, even if there is life in the vehicle, the rate of increase of CO2 concentration tends to decrease as the number of people in the vehicle decreases, so it may take time until life is determined to be present.

[0096] In contrast, in the first embodiment, according to equation (1), the estimated CO2 concentration C0 is calculated based on the difference between the CO2 concentration detection signal C(0) at the initial time point after parking and the CO2 concentration sensor 2 detection signal C (30s or 90s) after a predetermined time. Therefore, even when the CO2 concentration inside the vehicle is relatively high, erroneous judgments can be suppressed, and judgments can be made with higher accuracy.

[0097] Furthermore, by estimating the CO2 concentration inside the vehicle when it is assumed to be in a steady state, namely the estimated CO2 concentration value C0, the presence of organisms inside the vehicle is determined based on this estimated CO2 concentration value C0. Therefore, even if the CO2 concentration inside the vehicle has not actually changed, the determination can be made. For example, the presence of organisms inside the vehicle can be detected after approximately 30 seconds or approximately 90 seconds have passed since the vehicle was determined to be parked. This allows for a much earlier determination than by comparing the CO2 concentration or the rate of increase in the CO2 concentration with a threshold value.

[0098] In addition, Figure 3 In the flowchart shown, in step S7, it is set that time point t1 = 0 seconds and time point t2 = 30 seconds in formula (1), and the change rate dC(t) / dt of the CO2 concentration at time point t = 30 seconds is estimated, and the CO2 concentration estimated value C0 at time point t = 30 seconds is estimated using this change rate dC(t) / dt. Similarly, in step S12, it is set that time point t1 = 0 seconds and time point t2 = 90 seconds in formula (1), and the change rate dC(t) / dt of the CO2 concentration at time point t = 90 seconds is estimated, and the CO2 concentration estimated value C0 at time point t = 90 seconds is estimated using this change rate dC(t) / dt, but it is not limited to this.

[0099] Time points t1 and t2 simply refer to different times when the vehicle is in the parked state. When time point t2 is set to a time point later than time point t1, such as... Figure 3 As shown, time point t2 can be the same time point as when the estimated CO2 concentration C0 is calculated (e.g., in the case of step S7, time point t = 30 seconds), or it can be a different time point. Alternatively, the same rate of change of CO2 concentration dC(t) / dt can be used to estimate the estimated CO2 concentration C0 in both steps S7 and S12.

[0100] In addition, Figure 3In the flowchart shown, the decision process ends after the time constant τ is updated through step S21. However, it can also be set that while the vehicle is still in the parking state, the time constant τ is updated at arbitrary intervals such as every few hours or every few days, using the same process as steps S15 to S21.

[0101] In addition, the CO2 concentration sensor 2 does not need to be specially set up as a sensor for in-vehicle anomaly detection device. For example, in the case of a vehicle equipped with a CO2 concentration sensor for ventilation control based on CO2 concentration or an alcohol detector with a CO2 concentration sensor, the CO2 concentration sensor used for the alcohol detector can be used as the CO2 concentration sensor 2 for in-vehicle anomaly detection device. Alternatively, other CO2 concentration sensors mounted on the vehicle can be used as CO2 concentration sensors for in-vehicle anomaly detection device.

[0102] <Second Implementation Method>

[0103] <Structure of Vehicle Interior Anomaly Detection Device 1-1>

[0104] Figure 5 This is a schematic structural diagram showing an example of the in-vehicle anomaly detection device 1-1 according to the second embodiment of the present invention. Furthermore, the same symbols are used for the same parts as those in the in-vehicle anomaly detection device 1 according to the first embodiment described above, and detailed descriptions thereof are omitted.

[0105] The in-vehicle anomaly detection device 1-1 includes: a CO2 concentration sensor 2 that detects the concentration of carbon dioxide; a parking state detection unit 8 that detects the vehicle being in a parking state; a rate of change estimation unit 9 that estimates the rate of change of the carbon dioxide concentration inside the vehicle at time t when the vehicle is detected to be in a parking state, based on the detection signals C(t1) and C(t2) of the CO2 concentration sensor at two different time points t1 and t2 (where t2>t1) when the vehicle is detected to be in a parking state by the parking state detection unit 8; and a threshold determination unit 10 that determines the rate of change of the carbon dioxide concentration inside the vehicle at time t when the vehicle is detected to be in a parking state. The system uses the CO2 concentration sensor's detection signal C(t3) at any time point t3, the time constant τ stored in the time constant storage unit 6a, and the CO2 concentration outside the vehicle (Coutdoor) to determine the threshold Vth of the rate of change of carbon dioxide concentration; the anomaly determination unit 6-1 determines whether there is a living organism inside the vehicle as a detection target based on the comparison result between the rate of change of carbon dioxide concentration estimated by the rate of change estimation unit 9 and the threshold Vth determined by the threshold determination unit 10; and the notification unit 7 notifies the presence of a living organism when the anomaly determination unit 6-1 detects the presence of a living organism inside the vehicle.

[0106] The parking state detection unit 8 can be implemented by any one or a combination of the engine-off detection unit 3, the driver detection unit 4, and the door state detection unit 5 in the first embodiment. Among them, the engine-off detection unit 3 detects that the engine is in the off state, the driver detection unit 4 detects that there is no driver in the vehicle, and the door state detection unit 5 detects that all the doors of the vehicle are in the closed state.

[0107] The rate-of-change estimation unit 9 estimates the rate of change dC(t) / dt of the carbon dioxide concentration according to the following formula (6).

[0108] The threshold determination unit 10 uses a predetermined parameter K (0 < K ≤ 1) to determine the threshold Vth for the rate of change of the carbon dioxide concentration for determining whether there is a biological object to be detected in the vehicle according to the following formula (7). Then, the threshold determination unit 10 can determine that there is no biological object to be detected in the vehicle when dC(t) / dt < Vth, and / or determine that there is a biological object to be detected in the vehicle when dC(t) / dt > Vth.

[0109] dC(t) / dt

[0110] =[C(t2)-C(t1)] / (t2-t1)......(6)

[0111] Vth = -K×(C(t3)-Coutdoor) / τ......(7)

[0112] Here, when there is no biological object to be detected in the vehicle, the expected rate of change of the carbon dioxide concentration at any time point tx can be expressed by the following formula (8).

[0113] dC(tx) / dt<>

[0114] =-{[C(t3)-Coutdoor] / τ}·G(tx)......(8)

[0115] G(tx) in formula (8) is expressed by the following formula (9).

[0116] G(tx)=exp[-(tx-t3) / τ]......(9)

[0117] Thus, at the latest time point tmax allowed for determining whether there is a biological object to be detected in the vehicle, formula (8) becomes the following formulas (10) and (11).

[0118] dC(tmax) / dt

[0119] =-{[C(t3)|-Coutdoor] / τ}·G(tmax)......(10)

[0120] G(tmax)=exp[-(tmax-t3) / τ] ......(11)

[0122] Here, for G(tmax), it is obvious that G(tmax) > 0. In addition, since t3 is the time point when the vehicle is detected to be in a parked state, tmax ≥ t3. Therefore, G(tmax) satisfies the following equation (12).

[0123] 0<G(tmax)≤1......(12)

[0124] On the other hand, the specific value of the time constant τ varies depending on the design and condition of the vehicle body, but is expected to be approximately 100 to 500 minutes. In addition, if the detection of the organism being detected is delayed, it may be related to the health, life or death of the organism. Therefore, the actual limit allowed as tmax is approximately 15 to 30 minutes from the detection of the parking state. Here, t3 is the time point when the parking state is detected, so the maximum time allowed as tmax-t3 is approximately 15 to 30 minutes. Here, assuming that τ = 150 (minutes) and tmax-t3 = 15 (minutes), Equation (11) is expressed as the following Equation (13), and G(tmax) is rounded to one decimal place, so it is approximately 0.9.

[0125] G(tmax)=exp(-15 / 150)≈0.9 ......(13)

[0127] Furthermore, the CO2 concentration inside the vehicle is unlikely to be lower than the CO2 concentration outside the vehicle (Coutdoor), therefore [C(t3)-Coutdoor] / τ≥0. As a result, the following equation (14) holds.

[0128] dC(tx) / dt≤dC(tmax) / dt

[0129] =-{[C(t3)-Coutdoor] / τ}·exp[-(tmax-t3) / τ]

[0130] ≈-0.9·{[C(t3)-Coutdoor] / τ} ......(14)

[0132] The coefficient "0.9" in Equation (14) is a design value determined by conditions such as the design and state of the vehicle body, and the time allowed for detecting the living being to be detected. When G(tmax) is set to the design value K (where 0 < K ≤ 1) in Equation (14), the following Equation (15) (the aforementioned Equation (7)) is derived.

[0133] Vth = -K·{[C(t3) - Coutdoor] / τ}......15)

[0134] Equation (16) can be obtained based on Equation (15), the aforementioned Equation (7), and the aforementioned Equation (14).

[0135] dC(tx) / dt ≤ Vth......(16)

[0136] Therefore, for example, it can be determined that the living being to be detected is not in the vehicle when Equation (16) is satisfied. And / or, for example, it can be determined that the living being to be detected is in the vehicle when Equation (16) is not satisfied.

[0137] In fact, it is not easy to directly obtain the change rate dC(tx) / dt of the carbon dioxide concentration at an arbitrary time point. Therefore, Equation (6) can be used to obtain dC(tx) / dt.

[0138] C(t1) and C(t2) as measured values actually also include noise. Therefore, the value of K can be adjusted to avoid false judgments caused by this noise. For example, in order to make Equation (16) easier to satisfy, a smaller value can be used as K. At this time, it can also be assumed that the possibility of false judgment as non - existence increases even though there is a living being to be detected. For example, until a certain time has passed since the parking state was detected, the detection of the living being to be detected is attempted multiple times. Only when the living being to be detected is never detected, or is not detected with a certain frequency or more, is it finally determined that there is no living being to be detected in the vehicle.

[0139] In addition, although K is 0 < K ≤ 1, as described above, it is expected that τ is about 100 minutes to 500 minutes, and it is desired to complete the detection of the living being to be detected within about 15 minutes to 30 minutes from the detection of the parking state, and to avoid false judgments caused by noise. Therefore, sometimes it is preferred that K satisfies 0.5 < K < 1.

[0140] The CO2 concentration Coutdoor outside the vehicle can be a predetermined fixed value. That is, as a fixed value, a value generally used as the concentration of carbon dioxide in the atmosphere can be preset in advance. For example, as a fixed value, 500 ppm or 400 ppm, which is a representative value of the CO2 concentration in the natural environment, can be adopted, but it is not limited to this.

[0141] In other examples, the CO2 concentration outside the vehicle (Coutdoor) can be the carbon dioxide concentration outside the vehicle, determined by measurement. In this case, it can be as follows: Figure 6 As shown, the vehicle further includes a second CO2 concentration sensor 11 for measuring the CO2 concentration outside the vehicle (Coutdoor). Furthermore, the second CO2 concentration sensor 11 can be positioned in a location that is constantly in contact with the atmosphere outside the vehicle. Alternatively, the second CO2 concentration sensor 11 can measure the CO2 concentration outside the vehicle by allowing the atmosphere outside the vehicle to enter periodically or at an arbitrary timing.

[0142] Furthermore, C(t1), C(t2), and C(t3) need to be stored, for example, in a memory, while attempting to detect the target organism. On the other hand, C(t3) does not necessarily have to be different from both C(t1) and C(t2), so time t3 may be preferably time t1 or time t2. By using time t1 or time t2 as time t3, the number of values ​​required to be stored in order to attempt to detect the target organism can be reduced.

[0143] <Abnormality Determination Processing>

[0144] Then, accompanied by Figure 7 An example of a processing procedure of the abnormality determination processing executed in the vehicle interior abnormality detection device 1-1 is described with reference to the flowchart of FIG.

[0145] In the vehicle interior abnormality detection device 1-1, abnormality determination processing is performed at a predetermined, pre-set period. First, the detection signal from the parking state detection unit 8 is acquired (step S31). If the vehicle is not determined to be in the parking state (step S32), the process ends immediately. If the vehicle is determined to be in the parking state, the process proceeds to step S33. Next, the time at which the vehicle is determined to be in the parking state is set to t=0, and the time at which a waiting time of two minutes has elapsed from time t=0 is set to t=1. The detection signal from the CO2 concentration sensor 2 at time t=1 is read as C(t1) (step S34). The waiting time in step S33 (here, two minutes) is set to a time period in which fluctuations in the vehicle interior CO2 concentration associated with the opening and closing of parking doors, the stopping of the circulation fan, and the exiting of passengers stabilize, allowing for an appropriate value to be obtained as the vehicle interior CO2 concentration.

[0146] In step S34, the detection signal C(t1) of CO2 concentration sensor 2 is updated and stored in a predetermined storage area, such as storage unit 9m. Additionally, the detection signal C(t1) is used as C(t3), and the time constant τ, previously stored in time constant storage unit 6a, is read. The threshold Vth is then calculated according to equation (7) (processing based on the function of threshold determination unit 10). Finally, the obtained threshold Vth is updated and stored in a predetermined storage area, such as storage unit 10m.

[0147] Next, the process moves to step S35. After a 30-second waiting period from time t=1, it moves to step S36. The detection signal C(t2) of CO2 concentration sensor 2 at time t=2 is read and updated in a predetermined storage area, such as storage unit 9m. The waiting time in step S35 (30 seconds in this case) is set to determine the time during which a living being to be detected is present in the vehicle based on the increase in CO2 concentration after parking. For example, in the case of a child, pet, etc., the living being to be detected is set to about 30 seconds. Then, based on the detection signal C(t1) of CO2 concentration sensor 2 obtained in step S34 and the detection signal C(t2) of CO2 concentration sensor 2 obtained in step S36, the rate of change of CO2 concentration dC(t) / dt in the vehicle is calculated based on equation (6) and updated in a predetermined storage area, such as storage unit 9m (based on the function of the rate of change estimation unit 9).

[0148] Next, the process moves to step S37, where it is determined whether the rate of change of CO2 concentration dC(t) / dt calculated in step S36 is greater than the threshold Vth set in step S34. If dC(t) / dt>Vth, the process moves to step S38, where it is determined that a living organism exists in the vehicle and the notification unit 7 is activated to notify that a living organism exists in the vehicle (step S39) (processing based on the function of the anomaly determination unit 6-1).

[0149] On the other hand, in the processing of step S37, when the rate of change of CO2 concentration dC(t) / dt calculated in step S36 does not satisfy dC(t) / dt>Vth with the threshold Vth set in step S34, the process proceeds to step S41.

[0150] In step S41, it is determined whether more than 15 minutes have passed since the time point t=0 when the vehicle was detected to be in the parking state in step S32. If no more than 15 minutes have passed, the process returns to step S35.

[0151] Then, after 30 seconds, the process moves to step S36, where the detection signal from CO2 concentration sensor 2 is read again, used as C(t2), and updated and stored in the designated storage area (storage unit 9m). Then, in step S41, after more than 15 minutes have elapsed from time point t=0, the process moves to step S42, where it is determined that there are no living organisms inside the vehicle that are the target of the detection, and the process ends.

[0152] In step S41, the condition for determining that there is no biological target in the vehicle and proceeding to step S42, namely, the elapsed time of 15 minutes from time point t=0, is set for example to be the time during which the rate of change of CO2 concentration in the vehicle can be considered to exceed the threshold Vth if there is a biological target in the vehicle, at the latest until the elapsed time. That is, it is set to be the time during which the rate of change of CO2 concentration does not exceed the threshold Vth even if the elapsed time has passed.

[0153] <Effects of the in-vehicle anomaly detection device 1-1 according to the second embodiment>

[0154] In the in-vehicle anomaly detection device 1-1 according to the second embodiment, the presence of a living organism is determined by comparing the rate of change of CO2 concentration calculated from the CO2 concentration inside the vehicle at two different time points while the vehicle is parked with a threshold Vth calculated from the CO2 concentration inside the vehicle at one time point while the vehicle is parked, a time constant τ, and the CO2 concentration outside the vehicle (Coutdoor). The calculation of the rate of change of CO2 concentration and the threshold Vth is performed using a time constant τ that corresponds to vehicle characteristics such as airtightness, which can be considered a stable state. Therefore, the rate of change of CO2 concentration and the threshold Vth can be calculated with higher accuracy, resulting in improved accuracy in determining the presence of a living organism inside the vehicle.

[0155] In addition, if Figure 8 As shown, in the second embodiment, similarly to the first embodiment described above, after determining in step S42 that there is no living being detected inside the vehicle, a time constant update process (step S43) is performed, thereby updating the time constant τ. Furthermore, regarding the time constant update process (step S43), and... Figure 3 The processing of steps S15 to S21 can be carried out in the same way.

[0156] The embodiments of the present invention have been described above. These embodiments exemplify apparatus and methods for embodying the technical concept of the present invention. The technical concept of the present invention is not intended to specify the material, shape, structure, or configuration of structural components. Various modifications can be made to the technical concept of the present invention within the scope of protection defined by the claims.

[0157] Description of Reference Numerals

[0158] 1. 1-1: In-vehicle anomaly detection device; 2: CO2 concentration sensor; 3: Engine shutdown detection unit; 4: Driver detection unit; 5: Door status detection unit; 6. 6-1: Anomaly determination unit; 6a: Time constant storage unit; 7: Notification unit; 8: Parking status detection unit; 9: Rate of change estimation unit; 10: Threshold determination unit; 11: Second CO2 concentration sensor.

Claims

1. A vehicle abnormality detection device, comprising: A CO2 concentration sensor, which detects the carbon dioxide concentration in the vehicle; a parking state detection unit for detecting whether the vehicle is in a parking state; a time constant storage unit storing a time constant τ of a concentration change of the carbon dioxide concentration in the vehicle; a change rate estimating unit for estimating a change rate of the carbon dioxide concentration in the vehicle at time point t when the parking state is detected based on detection signals C(t1) and C(t2) of the CO2 concentration sensor at two different time points t1 and t2 when the parking state is detected by the parking state detecting unit; a carbon dioxide concentration estimating unit that estimates an estimated carbon dioxide concentration value C0 in the vehicle at a time point after a predetermined time has passed from the time point t, based on a detection signal C(t) of the CO2 concentration sensor at the time point t, the time constant τ stored in the time constant storage unit, and the rate of change estimated by the rate of change estimating unit; an abnormality determination unit that determines that the organism as the detection target is present in the vehicle when the estimated carbon dioxide concentration value C0 estimated by the carbon dioxide concentration estimation unit is greater than a threshold value set according to the organism as the detection target, and determines that the organism as the detection target is not present in the vehicle when the estimated carbon dioxide concentration value C0 is less than the threshold value set according to the organism as the detection target; as well as A time constant updating unit updates the time constant τ based on the detection signal of the CO 2 concentration sensor at a plurality of different time points when the abnormality determination unit determines that the organism to be detected is not present in the vehicle.

2. The in-vehicle abnormality detection device according to claim 1, wherein: The change rate estimation unit estimates the change rate dC(t) / dt according to the following equation (1): The carbon dioxide concentration estimation unit estimates the carbon dioxide concentration estimated value C0 according to the following equation (2): dC(t) / dt=[C(t2)-C(t1)] / (t2-t1) ……(1) CO=C(t)+τ×[dC(t) / dt]……(2).

3. The in-vehicle abnormality detection device according to claim 1 or 2, wherein: The time constant τ is determined by the airtightness of the vehicle interior and the volume of the vehicle interior.

4. The in-vehicle abnormality detection device according to claim 1 or 2, wherein: A plurality of the threshold values ​​are set according to the type of the living being to be detected.

5. The in-vehicle abnormality detection device according to claim 4, wherein: The abnormality determination unit compares the carbon dioxide concentration estimated value C0 estimated by the carbon dioxide concentration estimation unit with each of the multiple thresholds, and detects the type of organism present in the vehicle based on the size of a certain threshold when the carbon dioxide concentration estimated value C0 becomes above the multiple thresholds.

6. The in-vehicle abnormality detection device according to claim 1 or 2, wherein: The vehicle further includes a notification unit configured to notify that the living being as the detection target is present in the vehicle when the abnormality determination unit determines that the living being as the detection target is present in the vehicle.

7. The in-vehicle abnormality detection device according to claim 1 or 2, wherein: The CO2 concentration sensor is arranged behind the air inlet arranged at the bottom of the vehicle body or near the air vent on the top of the instrument panel. The CO 2 concentration sensor detects the carbon dioxide concentration in the vehicle in a state where an outside air fan is operated to allow outside air to enter the vehicle.

8. The in-vehicle abnormality detection device according to claim 1 or 2, wherein: The CO 2 concentration sensor is disposed near the floor of the vehicle, on the ceiling of the vehicle, or in the center of the vehicle.

9. The in-vehicle abnormality detection device according to claim 1 or 2, wherein: The CO2 concentration sensor includes a CO2 concentration sensor arranged behind an air intake port arranged close to the bottom of a vehicle body, a CO2 concentration sensor arranged near an air vent on the top of a dashboard, a CO2 concentration sensor arranged near the floor inside the vehicle, a CO2 concentration sensor arranged on the ceiling inside the vehicle, and two or more of a CO2 concentration sensor arranged at a central position inside the vehicle.

10. The in-vehicle abnormality detection device according to claim 1 or 2, wherein: The parking state detection unit determines that the vehicle is in the parking state when an engine of the vehicle is in an off state, a driver is not in a driver's seat, and all doors of the vehicle are in a closed state.

11. The in-vehicle abnormality detection device according to claim 1 or 2, wherein: The vehicle further includes an abnormality processing unit that opens a window of the vehicle to allow outside air to enter or activates a cooling or heating function when the abnormality determination unit determines that the organism to be detected is present in the vehicle.

12. A method for detecting abnormalities in a vehicle, performing the following processing: The CO2 concentration sensor detects the carbon dioxide concentration in the car when it is parked. estimating a rate of change of the carbon dioxide concentration in the vehicle at an arbitrary time point in the parking state based on detection signals of the CO2 concentration sensor at two different time points in the parking state, The carbon dioxide concentration in the vehicle at a time point after a predetermined time corresponding to the time constant has passed since the arbitrary time point is estimated based on the detection signal of the CO2 concentration sensor at the arbitrary time point, the time constant of the concentration change of the carbon dioxide concentration in the vehicle, and the estimated change rate. When the estimated carbon dioxide concentration in the vehicle is greater than a threshold value set according to the organism to be detected, it is determined that the organism to be detected is present in the vehicle; and when the estimated carbon dioxide concentration in the vehicle is less than the threshold value set according to the organism to be detected, it is determined that the organism to be detected is not present in the vehicle. The time constant is updated based on the detection signal of the CO 2 concentration sensor at a plurality of different time points when it is determined that the organism to be detected does not exist in the vehicle.

13. A vehicle in-vehicle abnormality detection device, comprising: A CO2 concentration sensor, which detects the carbon dioxide concentration in the vehicle; a parking state detection unit for detecting whether the vehicle is in a parking state; a time constant storage unit storing a time constant τ of a concentration change of the carbon dioxide concentration in the vehicle; A rate of change estimation unit estimates a rate of change dC(t) / dt of the carbon dioxide concentration in the vehicle at time point t when the parking state is detected based on detection signals C(t1) and C(t2) of the CO2 concentration sensor at two different time points t1 and t2 when the parking state is detected by the parking state detection unit, wherein t2>t1; a threshold value determination unit that determines a threshold value Vth based on a detection signal C(t3) of the CO2 concentration sensor at time t3 when the parking state is detected by the parking state detection unit, the time constant τ stored in the time constant storage unit, and the CO2 concentration Coutdoor outside the vehicle; an abnormality determination unit that determines whether or not a detection target organism exists in the vehicle based on a comparison result of the rate of change of the carbon dioxide concentration estimated by the rate of change estimation unit and a threshold value Vth determined by the threshold value determination unit, wherein when the rate of change of the carbon dioxide concentration is greater than the threshold value Vth determined by the threshold value determination unit, the abnormality determination unit determines that the detection target organism exists in the vehicle; and when the rate of change of the carbon dioxide concentration is less than the threshold value Vth, the abnormality determination unit determines that the detection target organism does not exist in the vehicle; as well as A time constant updating unit updates the time constant τ based on the detection signal of the CO 2 concentration sensor at a plurality of different time points when the abnormality determination unit determines that the organism to be detected is not present in the vehicle.

14. The in-vehicle abnormality detection device according to claim 13, wherein: The change rate estimation unit estimates the change rate dC(t) / dt according to the following equation (3): The threshold determination unit determines the threshold Vth using a predetermined parameter K according to the following equation (4), where 0 <K≤1, dC(t) / dt=[C(t2)-C(t1)] / (t2-t1) ……(3) Vth=-K×(C(t3)-Coutdoor) / τ......(4).

15. The in-vehicle abnormality detection device according to claim 14, wherein: The parameter K satisfies 0.5 <K<1。 16. The in-vehicle abnormality detection device according to any one of claims 13 to 15, wherein: The CO 2 concentration Coutdoor outside the vehicle is a predetermined fixed value.

17. The in-vehicle abnormality detection device according to any one of claims 13 to 15, wherein: The CO 2 concentration Coutdoor outside the vehicle is provided by a second CO 2 concentration sensor that detects the carbon dioxide concentration outside the vehicle.

18. The in-vehicle abnormality detection device according to any one of claims 13 to 15, wherein: The time point t1 and the time point t3 are the same time point.

19. The in-vehicle abnormality detection device according to any one of claims 13 to 15, wherein: The time constant τ is determined by the airtightness of the vehicle interior and the volume of the vehicle interior.

20. The in-vehicle abnormality detection device according to any one of claims 13 to 15, wherein: A plurality of the threshold values ​​are set according to the type of the living being to be detected.

21. The in-vehicle abnormality detection device according to claim 20, wherein: The abnormality determination unit compares the carbon dioxide concentration estimated value C0 estimated by the carbon dioxide concentration estimation unit with each of the multiple thresholds, and detects the type of organism present in the vehicle based on the size of a certain threshold when the carbon dioxide concentration estimated value C0 becomes above the multiple thresholds.

22. The in-vehicle abnormality detection device according to any one of claims 13 to 15, wherein: The vehicle further includes a notification unit configured to notify that the living being as the detection target is present in the vehicle when the abnormality determination unit determines that the living being as the detection target is present in the vehicle.

23. The in-vehicle abnormality detection device according to any one of claims 13 to 15, wherein: The CO2 concentration sensor is arranged behind the air inlet arranged at the bottom of the vehicle body or near the air vent on the top of the instrument panel. The CO 2 concentration sensor detects the carbon dioxide concentration in the vehicle in a state where an outside air fan is operated to allow outside air to enter the vehicle.

24. The in-vehicle abnormality detection device according to any one of claims 13 to 15, wherein: The CO 2 concentration sensor is disposed near the floor of the vehicle, on the ceiling of the vehicle, or in the center of the vehicle.

25. The in-vehicle abnormality detection device according to any one of claims 13 to 15, wherein: The CO2 concentration sensor includes a CO2 concentration sensor arranged behind an air intake port arranged close to the bottom of a vehicle body, a CO2 concentration sensor arranged near an air vent on the top of a dashboard, a CO2 concentration sensor arranged near the floor inside the vehicle, a CO2 concentration sensor arranged on the ceiling inside the vehicle, and two or more of a CO2 concentration sensor arranged at a central position inside the vehicle.

26. The in-vehicle abnormality detection device according to any one of claims 13 to 15, wherein: The parking state detection unit determines that the vehicle is in the parking state when an engine of the vehicle is in an off state, a driver is not in a driver's seat, and all doors of the vehicle are in a closed state.

27. The in-vehicle abnormality detection device according to any one of claims 13 to 15, wherein: The vehicle further includes an abnormality processing unit that opens a window of the vehicle to allow outside air to enter or activates a cooling or heating function when the abnormality determination unit determines that the organism to be detected is present in the vehicle.

28. A method for detecting abnormalities in a vehicle, performing the following processing: The CO2 concentration sensor detects the carbon dioxide concentration in the car when it is parked. estimating a rate of change of the carbon dioxide concentration in the vehicle at an arbitrary time point in the parking state based on detection signals of the CO2 concentration sensor at two different time points in the parking state, The threshold value Vth of the rate of change of the carbon dioxide concentration in the vehicle is determined based on the detection signal of the CO2 concentration sensor at the arbitrary time point, the time constant of the concentration change of the carbon dioxide concentration in the vehicle, and the CO2 concentration Coutdoor outside the vehicle, The estimated rate of change of the carbon dioxide concentration in the vehicle is compared with the threshold value Vth to determine whether there is a biological being as a detection target in the vehicle, wherein: When the estimated carbon dioxide concentration in the vehicle is greater than the threshold value Vth, it is determined that the organism to be detected is in the vehicle, and when the estimated carbon dioxide concentration in the vehicle is less than the threshold value Vth, it is determined that the organism to be detected is not in the vehicle. The time constant τ is updated based on the detection signal of the CO 2 concentration sensor at a plurality of different time points when it is determined that the organism to be detected does not exist in the vehicle.

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