Biometric detection system and biometric detection method

Abstract

To provide a biometric detection system and method that suppress false alarms and offer high usability. [Solution] A biodetection system 2 for detecting a living organism H in the passenger compartment 10 of a vehicle 1 comprises a biodetection unit 3 for detecting a living organism H in the passenger compartment 10 and a position change detection unit 4 for detecting a change in the position of the vehicle 1. The biodetection unit 3 changes the conditions for detecting a living organism H based on the detection results of the position change detection unit 4. With this configuration, it is possible to detect a living organism H while taking into account luggage B in the passenger compartment 10. Therefore, it becomes difficult to mistakenly detect vibrating luggage B as a living organism H, and false alarms can be effectively suppressed.

Description

Technical Field

[0001] The present invention relates to a living body detection system and a living body detection method.

Background Art

[0002] In recent years, incidents where infants are left behind in the cabins of private cars, shuttle buses and the like, regardless of intent or negligence, have become a major problem. Accordingly, leaving monitoring systems that monitor for infants being left behind in vehicle cabins have begun to be widely adopted, and in particular, installation of such systems has been mandated for shuttle buses.

[0003] Most of the existing leaving monitoring systems operate in conjunction with actions that occur when a user (driver) leaves the vehicle, such as door opening / closing and locking, and when an infant is detected inside the vehicle, the system is configured to notify the user and surrounding people that an infant has been left behind in the vehicle cabin via an alarm, sound generation using the vehicle's horn or the like, notification by light emission using the vehicle's lights (headlights, taillights, turn signal lights, room lights, etc.), and the like.

[0004] However, the position of the vehicle may change for some reason, such as conveyance in a mechanical multistory parking garage (movement of a pallet on which the vehicle is placed), towing by a tow truck, land transport by a truck or the like, marine transport by a ferry or the like, and the accompanying vibration may cause luggage in the vehicle cabin to vibrate. In this way, if detection of an infant is started while luggage is vibrating in the vehicle cabin, there is a risk that the vibrating luggage will be falsely detected as an infant. As a result, a false alarm may be triggered even in situations where no infant has been left behind, causing annoyance to the user or issuing a false notification to surrounding people. Therefore, usability (convenience) is poor.

[0005] To address these problems, for example, Patent Document 1 discloses an abandoned vehicle detection system that uses a vibration sensor to detect vehicle vibrations and detects a living being when the vehicle vibration is below a threshold, that is, when the vehicle vibration has sufficiently subsided. However, the configuration in Patent Document 1 only considers vibrations while the vehicle is stationary and does not consider changes in position at all. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2023-119923 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] This invention has been made in view of the above, and aims to provide a biometric detection system and biometric detection method that can effectively suppress false alarms and have excellent usability (convenience). [Means for solving the problem]

[0008] These objectives are achieved by the present invention as described in (1) and (2) below.

[0009] (1) A biometric detection system for detecting living organisms inside a vehicle, A biodetection unit for detecting the living body inside the vehicle interior, It includes a position change detection unit that detects changes in the position of the vehicle, The biodetection system is characterized in that the biodetection unit changes the conditions for detecting the living organism based on the detection result of the position change detection unit.

[0010] (2) A method for detecting living organisms inside a vehicle, A method for detecting a living organism, characterized by changing the conditions for detecting the living organism based on the change in the position of the vehicle. [Effects of the Invention]

[0011] In the biodetection system of the present invention, the conditions for detecting a living being are changed based on the detection results of the position change detection unit, that is, the change in the vehicle's position. With this configuration, it is possible to detect a living being while taking into account the vibration of luggage inside the vehicle. Therefore, it becomes less likely to mistakenly detect vibrating luggage as a living being, and false alarms can be effectively suppressed. As a result, a biodetection system with high usability is achieved.

[0012] Similarly, in the biodetection method of the present invention, the conditions for detecting a living being are changed based on the change in the vehicle's position. With this method, it is possible to detect a living being while taking into account the vibration of luggage inside the vehicle. Therefore, it becomes less likely to mistakenly detect vibrating luggage as a living being, and false alarms can be effectively suppressed. As a result, a biodetection method with high usability is obtained. [Brief explanation of the drawing]

[0013] [Figure 1] This figure shows a vehicle equipped with a biodetection system according to a preferred embodiment. [Figure 2] This is a block diagram showing the configuration of a biometric detection system. [Figure 3] This graph shows an example of the level of biodetection when no living organism is present. [Figure 4] This graph shows an example of the biodetection level when a living organism is present. [Figure 5] This diagram shows luggage placed on the rear seats of a vehicle. [Figure 6] This graph illustrates the problems with conventional methods. [Figure 7] This figure shows an example of a mechanical multi-story parking garage. [Figure 8] This table shows the vehicle's status, the threshold values ​​for each status, and the detection period. [Figure 9] This is a diagram illustrating how to determine the condition of a vehicle. [Figure 10]This is a flowchart showing a living body detection method using a living body detection system. [Figure 11] This is a flowchart showing a modified example of the living body detection method using the living body detection system. [Modes for Carrying Out the Invention]

[0014] Hereinafter, the living body detection system and the living body detection method of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

[0015] <First Embodiment> Figure 1 is a diagram showing a vehicle equipped with a living body detection system according to a preferred embodiment. Figure 2 is a block diagram showing the configuration of the living body detection system. Figure 3 is a graph showing an example of the living body detection level when no living body is present. Figure 4 is a graph showing an example of the living body detection level when a living body is present. Figure 5 is a diagram showing a state where luggage is placed on the rear seat of the vehicle. Figure 6 is a graph for explaining the conventional problems. Figure 7 is a diagram showing an example of a mechanical multistory parking lot. Figure 8 is a table showing the vehicle state, and the threshold value and detection period in each state. Figure 9 is a diagram for explaining the vehicle state determination method. Figure 10 is a flowchart showing a living body detection method using the living body detection system. Figure 11 is a flowchart showing a modified example of the living body detection method using the living body detection system.

[0016] As shown in Figure 1, the vehicle 1 is equipped with a living body detection system 2 that detects a living body H in the vehicle cabin 10. The living body detection system 2 is suitably used as a leaving-prevention system for detecting a living body H left behind in the vehicle cabin 10, particularly an infant. This can effectively reduce the risk that the living body H is exposed to danger due to the harsh environment inside the vehicle cabin 10. However, the living body H to be detected is not limited to infants, and may be, for example, humans other than infants, or pet animals (pets) such as dogs and cats. Further, the application of the living body detection system 2 is not limited to the leaving-prevention system, and for example, it can also be used as a gesture sensor for detecting a user's motion (gesture). Further, the vehicle 1 is not particularly limited, but is typically a passenger car such as a light vehicle, a compact car, a standard car, or a medium or large-sized large vehicle. However, the vehicle 1 is not limited to passenger cars, and may be, for example, a train, an airplane, a ship, or the like.

[0017] As shown in Figure 1, the living body detection system 2 is constructed of a living body detection unit 3 that detects the living body H in the vehicle cabin 10, a position change detection unit 4 that detects a position change of the vehicle 1, an alarm unit 5 that issues an alarm when the living body detection unit 3 detects the living body H, a drive control unit 6 that performs integrated control of these components, and a communication device 9 carried by the user U. Such a living body detection system 2 starts detection of the living body H upon detecting a detection start trigger, and when detecting the living body H in the vehicle cabin 10, notifies people around the vehicle 1 of that fact via a horn or the like, or notifies the user U via the communication device 9. However, the configuration of the living body detection system 2 is not particularly limited, and for example, the communication device 9 may be omitted. In this case, the configuration may be such that when the living body H in the vehicle cabin 10 is detected, people around the vehicle 1 are notified. Conversely, the notification to people around via a horn or the like may be omitted. In this case, the configuration may be such that when the living body H in the vehicle cabin 10 is detected, the user U is notified via the communication device 9.

[0018] Hereinafter, each unit constituting the living body detection system 2 will be described in order.

[0019] «Communication Device 9» The communication device 9 is carried by user U. The communication device 9 is also capable of communicating with the biometric detection unit 3. In particular, the communication device 9 in this embodiment is a smartphone. Because smartphones have screens, necessary information can be more reliably communicated to user U through screen displays. Furthermore, because smartphones are widely used and user U already owns one, it is easier to construct the biometric detection system 2. However, the communication device 9 is not limited to a smartphone; for example, it may be a wearable device such as a smartwatch, smart glasses, or smart ring, or a tablet device. Alternatively, the communication device 9 may be a smart key for the vehicle 1, an electronic tag, or the like.

[0020] <Position change detection unit 4> The position change detection unit 4 has the function of detecting changes in the position of the vehicle 1. The position change of the vehicle 1 includes both horizontal and vertical movement of the vehicle 1. The position change can also be expressed as the amount of movement per unit time. The position change detection unit 4 is not particularly limited and can include, for example, various inertial sensors such as acceleration sensors and angular velocity sensors, and various satellite positioning systems such as GPS (Global Positioning System). A barometric pressure sensor can also be used for detecting height. Furthermore, multiple units can be used in combination.

[0021] <<Biometric detection unit 3>> The biodetection unit 3 is activated when it detects a detection start trigger and detects a living organism H using radar. Since the biodetection unit 3 is powered by the vehicle's battery, it can operate even when the vehicle's engine is stopped. The number of biodetection units 3 placed in the passenger compartment 10 is not limited to one, but may be two or more. The number of biodetection units 3 can be appropriately set according to the size of the passenger compartment 10, the number of seating rows, etc.

[0022] The biodetection unit 3 is a UWB (Ultra-Wide Band) communication device that communicates with the communication device 9, and is used as a UWB radar for detecting biological H. However, the radar used in the biodetection unit 3 is not particularly limited and may be, for example, an FMCW (Continuous Frequency Modulation) radar or a CW (Continuous Wave) radar. Also, the radio waves used for communication with the communication device 9 and the radio waves used for detecting biological H may be different from each other. For example, communication may be performed using UWB communication, and biological H may be detected using an FMCW radar or a CW radar.

[0023] As shown in Figure 2, the biodetection unit 3 includes a transmitting antenna 31, three receiving antennas 321, 322, and 323, and a control unit 33. Furthermore, the control unit 33 includes a transmitting unit 34, a receiving unit 35, and a processing unit 36. In order to improve biodetection accuracy, at least the transmitting antenna 31 and the receiving antennas 321, 322, and 323 are positioned on the ceiling of the vehicle interior 10. This makes it difficult for obstacles such as seats to be interposed between these antennas and the living body H, so that the radio waves transmitted from the transmitting antenna 31 can easily reach the living body H, and the radio waves reflected by the living body H can easily reach the receiving antennas 321, 322, and 323. As a result, biodetection accuracy is improved. However, the arrangement of the transmitting antenna 31 and the receiving antennas 321, 322, and 323 is not particularly limited.

[0024] The control unit 33 is, for example, a computer and, as shown in Figure 3, has one or more processors 331 that process information and a memory 332 that is communicably connected to the processors 331.

[0025] Furthermore, the processor 331 is an arithmetic unit that performs arithmetic processing such as signal manipulation based on computer-readable instructions such as one or more microprocessors, microcomputers, microcontrollers, digital signal processors (DSPs), central processing units (CPUs), memory control units (MCUs), graphics processing units (GPUs), state machines, logic circuits, application-specific integrated circuits (ASICs), or combinations thereof.

[0026] Furthermore, memory 332 is a computer-readable medium including, for example, volatile storage media (e.g., RAM, SRAM, DRAM), non-volatile storage media (e.g., ROM, EPROM, EEPROM, flash memory, hard disk, solid state drive, optical disc, CD-ROM, digital multipurpose disc (DVD), Blu-ray disc, magnetic cassette, magnetic tape, magnetic disk), or a combination thereof.

[0027] Such a memory 332 is connected to the processor 331 in a communicative manner and stores programs and data that can be executed by the processor 331. The processor 331 reads and executes the programs stored in the memory 332. As a result, the control unit 33 functions as a transmitter 34, a receiver 35, and a processing unit 36.

[0028] Furthermore, the transmitting unit 34 includes a pulse signal generation unit 341 that generates pulse signals, a local oscillator 342, and a multiplier 343. The pulse signal generated by the pulse signal generation unit 341 is multiplied with the local oscillator signal emitted from the local oscillator 342 by the multiplier 343, thereby modulating (upconverting) it to a predetermined frequency band, for example, a short wavelength of about 6.0 GHz to 8.5 GHz. The pulse signal upconverted by the multiplier 343 is then amplified by a power amplifier PA and transmitted from the transmitting antenna 31 as a pulsed radio wave (pulse wave). Hereinafter, the radio wave transmitted from the transmitting antenna 31 will also be referred to as the transmitted wave Tw.

[0029] Receiving antennas 321, 322, and 323 each receive the reflected wave Rw that is formed when the transmitted wave Tw is reflected by an object such as a living organism H.

[0030] The receiving unit 35 includes multipliers 351 and 352, a π / 2 shifter 353, and an RF switch 354. The multipliers 351 and 352 are connected to the receiving antennas 321, 322, and 323 via the RF switch 354. The RF switch 354 periodically switches between a state where receiving antenna 321 is connected to multipliers 351 and 352, a state where receiving antenna 322 is connected to multipliers 351 and 352, and a state where receiving antenna 323 is connected to multipliers 351 and 352. The reflected waves Rw received by receiving antennas 321, 322, and 323 are sequentially introduced to the multipliers 351 and 352 via a low-noise amplifier LNA in accordance with the switching cycle of the RF switch 354.

[0031] The local oscillator signal is input to multiplier 351. Therefore, in multiplier 351, the reflected wave Rw is demodulated (down-converted) so that it is in phase with the local oscillator signal, and the in-phase component signal Si (I component) is derived. On the other hand, the local oscillator signal that has been phase-shifted by the π / 2 shifter 353 is input to multiplier 352. Therefore, in multiplier 352, the reflected wave Rw is demodulated (down-converted) so that it is in phase orthogonal to the local oscillator signal, and the orthogonal-phase component signal Sq (Q component) is derived.

[0032] Furthermore, the in-phase component signal Si and the quadrature-phase component signal Sq are input to the processing unit 36 ​​via a low-pass filter (LPF), a variable gain amplifier (VGA), and an analog-to-digital converter (ADC), respectively.

[0033] The processing unit 36 ​​detects living organisms H within the detection area based on the in-phase component signal Si and the orthogonal phase component signal Sq. Such a processing unit 36 ​​includes a generation unit 361 that generates a living organism detection level L, which is a value for determining the presence or absence of living organisms, from the in-phase component signal Si and the orthogonal phase component signal Sq, and a determination unit 362 that determines the presence or absence of living organisms H by comparing the living organism detection level L with a threshold D.

[0034] The generation unit 361 first generates a received signal based on the in-phase component signal Si and the quadrature phase component signal Sq input from the receiving unit 35. Specifically, each time a transmission wave Tw (pulse wave) is transmitted from the transmitting antenna 31, the generation unit 361 generates the in-phase component signal Si and the quadrature phase component signal Sq, and stores the generated in-phase component signal Si and quadrature phase component signal Sq as a received signal, which is a complex received signal. The generation unit 361 further acquires a time-series signal for each detection distance by repeating the storage of this received signal a predetermined number of times.

[0035] Furthermore, the generation unit 361 generates a biological detection level L based on the time-series signal. The biological detection level L is an indicator that shows a large value when a biological organism H is present, and can be defined, for example, as the power of the human respiratory frequency band (0.1 Hz to 1.0 Hz) included in the time-series signal. Such a biological detection level L can be obtained, for example, by performing a frequency analysis of the respiratory frequency band on the time-series signal using an analysis method such as FFT (Fast Fourier Transform). Note that the biological detection level L is not the only value used to determine the presence or absence of a biological organism.

[0036] The determination unit 362 determines the presence or absence of a living organism H by comparing the biological detection level L generated by the generation unit 361 with a threshold D. Specifically, the determination unit 362 has a threshold D for the biological detection level L, and as shown in Figure 3, if the biological detection level L is less than the threshold D, it determines that there is no living organism H and the location is "unoccupied". Conversely, as shown in Figure 4, if the biological detection level L is equal to or greater than the threshold D, it determines that there is a living organism H and the location is "occupied".

[0037] In this embodiment, by utilizing three time-series signals generated from reflected waves Rw with different paths (a time-series signal corresponding to the reflected wave Rw received by the receiving antenna 321, a time-series signal corresponding to the reflected wave Rw received by the receiving antenna 322, and a time-series signal corresponding to the reflected wave Rw received by the receiving antenna 323), the distance and angle between the biodetection unit 3 and the living organism H can be detected, for example, using AoA (Angle of Arrival). Therefore, if a living organism H is present, the determination unit 362 identifies the position of the living organism H. In this way, by identifying not only the presence or absence of the living organism H but also its position, it is possible to determine with higher accuracy whether the detected living organism H is inside or outside the vehicle compartment 10. The position of the living organism H may be in three-dimensional coordinates or in two-dimensional coordinates with a fixed height direction.

[0038] Here, we will briefly explain the conventional problems. As already explained, as shown in Figure 5, if there is luggage B inside the vehicle compartment 10, luggage B may vibrate due to vibrations caused by changes in the position of the vehicle 1. When the biodetection unit 3 performs biodetection while luggage B is vibrating, if the vibration frequency of luggage B is close to the respiratory frequency band, as shown in Figure 6, a biodetection level L above the threshold D may appear during the detection period Q, leading to a false detection of the vibrating luggage B as a living person H, and further, a false alarm to that effect. Such false alarms can be annoying to the user U and cause trouble for people around the vehicle 1. Therefore, usability (convenience) is reduced.

[0039] To prevent such false alarms, it is desirable to have a low false positive rate for manned vehicles (the probability of detecting a biological organism H when the vehicle compartment 10 is unoccupied). In this case, for example, the threshold D can be increased so that the biological detection level L for "unoccupied" vehicles does not exceed threshold D. However, increasing threshold D also makes it less likely for the biological detection level L for "occupied" vehicles to exceed threshold D, thus lowering the manned detection rate (the probability of detecting a biological organism H when the vehicle compartment 10 is occupied), which may lead to missing biological organism H. Thus, there is a trade-off relationship between the manned detection rate and the manned false positive rate.

[0040] Furthermore, in the biodetection system 2, the longer the detection period Q for detecting a biological organism H, the greater the number of time-series signal samples. As a result, the influence of sudden noise is reduced, and a biodetection level L is obtained in which periodic signal components (up and down movement of the chest due to respiration) are emphasized. Consequently, the biodetection level L for "unoccupied" and "occupied" environments becomes larger, making it less likely for the biodetection level L for "unoccupied" environments to exceed the threshold D, while the biodetection level for "occupied" environments to exceed the threshold D more easily. Therefore, the frequency of false alarms is reduced, and usability is improved. However, on the other hand, the longer the detection period Q, the later the alarm timing. Thus, there is a trade-off relationship between the frequency of false alarms and the timing of alarm activation.

[0041] As described above, the threshold D and detection period Q in biometric detection processing are important for suppressing false alarms and improving usability. Furthermore, since the biometric detection level L for "unmanned" areas changes significantly due to the vibration of luggage B, it is important to determine the threshold D and detection period Q according to the vibration conditions of luggage B.

[0042] Therefore, in the biodetection system 2, the state of vehicle 1 (susceptibility of luggage B to vibration) is determined based on the change in the vehicle 1's position detected by the position change detection unit 4, and an appropriate threshold D and detection period Q are set for each determined state of vehicle 1, thereby changing the conditions for detecting a biological organism H for each state of vehicle 1. With this configuration, a biological organism H can be detected under conditions that take into account the presence or absence of luggage B and the magnitude of the vibration of luggage B. As a result, it becomes less likely to mistakenly detect a vibrating luggage B as a biological organism H, and false alarms can be effectively suppressed. As a result, the biodetection system 2 becomes highly user-friendly. In particular, the method of determining the threshold D and detection period Q for each state of vehicle 1 allows for easy and accurate changes to the conditions for detecting a biological organism H. This will be explained in detail below.

[0043] The biometric detection unit 3 determines whether the state of vehicle 1 is stopped J1 or moving J2 based on the change in vehicle 1's position detected by the position change detection unit 4. Stopped J1 is the state in which vehicle 1, with its engine stopped, is stationary. Therefore, in stopped J1, there is no change in the position of vehicle 1, and the cargo B inside the passenger compartment 10 does not vibrate substantially. On the other hand, moving J2 is the state in which vehicle 1, with its engine stopped, is moving by means other than self-propulsion. Therefore, in moving J2, there is a change in the position of vehicle 1, and the cargo B inside the passenger compartment 10 is prone to vibration due to the vibrations caused by the change in position.

[0044] The situations that can occur in the moving state J2 are not particularly limited, but in this embodiment, for example, we envision transport to a predetermined position in a mechanical multi-story parking garage as shown in Figure 7 (movement of the valet on which vehicle 1 is placed), towing of vehicle 1 by a tow truck, land transport of vehicle 1 by truck, etc., and sea transport of vehicle 1 by ferry, etc.

[0045] Then, as shown in Figure 8, the biodetection unit 3 sets different conditions (at least one of the threshold D and the detection period Q) for detecting a living organism H in a stationary state J1 where the vehicle 1 does not change position, and in a moving state J2 where the vehicle 1 does change position.

[0046] Specifically, in the stopped state J1, since vehicle 1 is stationary, there is almost no risk of cargo B vibrating. Therefore, even if the threshold D is set low, the biometric detection level L in the "unmanned" state is unlikely to exceed threshold D. Also, even if the detection period Q is short, a difference in biometric detection level L is likely to occur between the "unmanned" and "manned" states. Therefore, in the stopped state J1, the threshold D is set low and the detection period Q is set short. With these settings, false alarms in the stopped state J1 can be effectively suppressed. In addition, the false detection rate for manned vehicles can be kept low, and the timing of alarm activation can be advanced.

[0047] On the other hand, in moving state J2, since vehicle 1 is moving, cargo B is more likely to vibrate. Therefore, when cargo B is vibrating, the biometric detection level L tends to be high even when the vehicle is unoccupied. Also, when cargo B is vibrating, if the detection period Q is short, it is difficult for there to be a difference in biometric detection level L between "unoccupied" and "occupied" states. Therefore, in moving state J2, the threshold D is set higher than in stationary state J1, and the detection period Q is set longer than in stationary state J1. This makes it easier for there to be a difference in biometric detection level L between "unoccupied" and "occupied" states, and makes it difficult for the biometric detection level L in the "unoccupied" state to exceed the threshold D. Therefore, with these settings, false alarms in moving state J2 can be effectively suppressed.

[0048] In this way, by appropriately setting the threshold D and detection period Q in the stationary state J1 and the moving state J2, false alarms can be effectively suppressed in both the stationary state J1 and the moving state J2. Therefore, a highly user-friendly biometric detection system 2 is achieved.

[0049] As mentioned above, in the stopped state J1, since vehicle 1 is stationary, cargo B does not normally vibrate. However, under special circumstances, vehicle 1 may shake, and cargo B may vibrate as a result of that shaking. Therefore, the biodetection unit 3 further distinguishes the stopped state J1 into a first stopped state J11 in which vehicle 1 is stable and less prone to shaking, and a second stopped state J12 in which vehicle 1 is more unstable and more prone to shaking than in the first stopped state J11.

[0050] The first stopping state J11 is, for example, a state where the vehicle is stopped on the ground or on something fixed to the ground. Therefore, in the first stopping state J11, the vehicle 1 is stable and there is little risk of the cargo B vibrating while stopped. For this reason, even if the threshold D is set low, the biometric detection level L in the "unmanned" state is unlikely to exceed the threshold D. Also, even if the detection period Q is short, a difference in biometric detection level L is likely to occur between the "unmanned" and "manned" states. Therefore, in the first stopping state J11, the threshold D is set low and the detection period Q is set short. With such settings, false alarms in the first stopping state J11 can be effectively suppressed. In addition, the false detection rate in the manned state can be kept low and the alarm timing can be advanced. In the following, the threshold D of the first stopping state J11 will also be referred to as threshold D11, and the detection period Q of the first stopping state J11 will also be referred to as detection period Q11.

[0051] On the other hand, the second stopped state J12 is, for example, a state in which vehicle 1 is placed on a valet in a mechanical multi-story parking garage. Therefore, in the second stopped state J12, vehicle 1 may shake along with the valet due to strong winds, etc., and as a result, cargo B may vibrate. However, the vibration of cargo B is considered to be smaller than the vibration in the moving state J2. For this reason, in the second stopped state J12, the threshold D is set to a value higher than the threshold D11 of the first stopped state J11 and lower than that of the moving state J2, and the detection period Q is set to a value longer than the detection period Q11 of the first stopped state J11 and shorter than that of the moving state J2. As a result, even if cargo B vibrates, the "unmanned" biometric detection level L is less likely to exceed the threshold D. With such settings, false alarms in the second stopped state J12 can be effectively suppressed. In the following, the threshold D of the second stopped state J12 will also be referred to as threshold D12, and the detection period Q of the second stopped state J12 will also be referred to as detection period Q12.

[0052] Furthermore, the biodetection unit 3 further distinguishes the movement state J2 into a first movement state J21 in which the vehicle 1 is being moved by towing by a tow truck, land transport by truck, sea transport by ferry, etc., and a second movement state J22 in which the vehicle 1 is moving within a mechanical multi-story parking garage. This allows for a more detailed classification of the state of the vehicle 1. Since there is virtually no difference in the susceptibility of the cargo B to vibration between these first and second movement states J21 and J22, that is, the cargo B is equally susceptible to vibration in both, in this embodiment the threshold D and detection period Q for the first and second movement states J21 and J22 are the same. The threshold D for the first and second movement states J21 and J22 is set to be greater than the threshold D12, and the detection period Q for the first and second movement states J21 and J22 is set to be longer than the detection period Q12. With these settings, false alarms in the first and second movement states J21 and J22 can be effectively suppressed. In the following, the threshold D for the first movement state J21 will also be referred to as threshold D21, and the detection period Q for the first movement state J21 will also be referred to as detection period Q21. Similarly, the threshold D for the second movement state J22 will also be referred to as threshold D22, and the detection period Q for the second movement state J22 will also be referred to as detection period Q22.

[0053] However, the invention is not limited to this, and for example, at least one of the threshold D and the detection period Q may be different in the first and second movement states J21 and J22. Also, for example, in the first movement state J21, the threshold D21 and the detection period Q21 may be changed based on the magnitude of the change in the position of the vehicle 1 detected by the position change detection unit 4. In other words, the greater the change in the position of the vehicle 1, the greater the threshold D21 may be increased and the longer the detection period Q21 may be increased. The same applies to the second movement state J22.

[0054] As described above, in the biological detection unit 3, the threshold D is in the relationship first stop state J11 < second stop state J12 < first movement state J21 = second movement state J22, and the detection period Q is in the relationship first stop state J11 < second stop state J12 < first movement state J21 = second movement state J22.

[0055] If the state of vehicle 1 determined based on the detection result of the position change detection unit 4 is the first stopped state J11, the determination unit 362 determines the presence or absence of a living organism H using the threshold D11 and detection period Q11 set for the first stopped state J11. If the state of vehicle 1 determined based on the detection result of the position change detection unit 4 is the second stopped state J12, the determination unit 362 determines the presence or absence of a living organism H using the threshold D12 and detection period Q12 set for the second stopped state J12. If the state of vehicle 1 determined based on the detection result of the position change detection unit 4 is the first moving state J21, the determination unit 362 determines the presence or absence of a living organism H using the threshold D21 and detection period Q21 set for the first moving state J21. If the state of vehicle 1 determined based on the detection result of the position change detection unit 4 is the second moving state J22, the determination unit 362 determines the presence or absence of a living organism H using the threshold D22 and detection period Q22 set for the second moving state J22. This configuration allows for a low rate of false detections in each state J11, J12, J21, and J22. Therefore, it results in a highly user-friendly biometric detection system 2.

[0056] The detection period Q11 in the first stopped state J11 is not particularly limited, but is preferably about 3 to 5 seconds. The detection period Q12 in the second stopped state J12 is not particularly limited, but is preferably about 5 to 10 seconds. The detection periods Q21 and Q22 in the first moving state J21 and the second moving state J22 are not particularly limited, but are preferably about 10 to 30 seconds. With this configuration, the detection period Q in each state will be appropriate. Furthermore, it is possible to suppress excessive lengthening of the detection period Q, and the alarm timing can be made sufficiently early in all states.

[0057] Furthermore, the method for determining the state of vehicle 1 based on the position change of vehicle 1 detected by the position change detection unit 4 is not particularly limited. For example, in this embodiment, as shown in Figure 9, when the engine of vehicle 1 is turned OFF, it is determined to be the first stopped state J11. If a horizontal position change occurs in vehicle 1 while in the first stopped state J11, it is determined to be the first moving state J21. If there is no further horizontal position change in vehicle 1 while in the first moving state J21, it is determined to be the first stopped state J11. If a vertical position change occurs in vehicle 1 while in the first stopped state J11 or the first moving state J21, it is determined to be the second moving state J22. If there is no further position change while in the second moving state J22, it is determined to be the second stopped state J12. Furthermore, if a positional displacement occurs in vehicle 1 while it is in the second stopped state J12, it is determined to be in the second moving state J22. If the vehicle 1 is unlocked or its doors are opened or closed while it is in the second stopped state J12, it is determined to be in the first stopped state J11. This method allows for the determination of the state of vehicle 1 in a simple manner.

[0058] ≪Information Unit 5≫ When the biometric detection unit 3 detects a living person H inside the vehicle compartment 10, the alarm unit 5 alerts people in the vicinity and the user U to that fact (that a living person H has been left behind inside the vehicle compartment 10). The method of alerting people in the vicinity is not particularly limited, but examples include flashing lights on various parts of the vehicle 1 or sounding the horn. Alternatively, for example, the alarm unit 5 may emit an alarm sound from a speaker or the like. On the other hand, the method of alerting the user U is not particularly limited, but for example, communication with the communication device 9 may be used to display the message "A living person H has been left behind inside the vehicle compartment 10" on the screen of the communication device 9 along with an incoming call sound or vibration. When using the biometric detection system 2, a dedicated application (application program) may be installed on the communication device 9 in advance, and notifications may be made using this application. In this way, the convenience of the biometric detection system 2 is further improved by using a dedicated application.

[0059] <Drive Control Unit 6> The drive control unit 6 provides overall control over the operation of the aforementioned biometric detection unit 3, position change detection unit 4, and alarm generation unit 5. Such a drive control unit 6 is, for example, composed of a computer and includes one or more processors 61 that process information, and a memory 62 that is communicatively connected to the processors 61.

[0060] Furthermore, the processor 61 is an arithmetic unit that performs arithmetic processing such as signal manipulation based on computer-readable instructions such as one or more microprocessors, microcomputers, microcontrollers, digital signal processors (DSPs), central processing units (CPUs), memory control units (MCUs), graphics processing units (GPUs), state machines, logic circuits, application-specific integrated circuits (ASICs), or combinations thereof.

[0061] Furthermore, memory 62 is a computer-readable medium including, for example, volatile storage media (e.g., RAM, SRAM, DRAM), non-volatile storage media (e.g., ROM, EPROM, EEPROM, flash memory, hard disk, solid state drive, optical disc, CD-ROM, digital multipurpose disc (DVD), Blu-ray disc, magnetic cassette, magnetic tape, magnetic disk), or a combination thereof.

[0062] Such a memory 62 is connected to the processor 61 in a communicative manner, and stores programs and data that can be executed by the processor 61. The processor 61 reads and executes the programs stored in the memory 62, thereby functioning as a drive control unit 6.

[0063] The configuration of the biodetection system 2 has been described above. Next, the biodetection method using the biodetection system 2 will be explained based on the flowchart shown in Figure 10.

[0064] First, in step S1, the biometric detection system 2 waits for the biometric detection unit 3 to be activated until a detection start trigger occurs. The detection start trigger is the locking of the vehicle 1. This allows the biometric detection system 2 to be activated at the same time that user U attempts to leave the vehicle 1, enabling rapid detection of the biological organism H. In this embodiment, in addition to the locking of the vehicle 1, the detection start trigger also occurs periodically at predetermined time intervals (for example, every 10 minutes) from the time the vehicle is stopped. With this configuration, the system can respond appropriately even if user U leaves the vehicle 1 without locking it. Furthermore, by periodically detecting the biological organism H, it is possible to more effectively suppress the chances of missing the biological organism H. The time the vehicle is stopped is, for example, the time the engine is turned off.

[0065] Then, when the detection start trigger is detected, the biodetection system 2 activates the biodetection unit 3 as step S2. Then, as step S3, the biodetection system 2 detects the change in the position of vehicle 1 based on the detection result of the position change detection unit 4. Next, as step S4, the biodetection system 2 determines the state of vehicle 1 based on the detected change in the position of vehicle 1. That is, it determines whether the current state of vehicle 1 is the first stopped state J11, the second stopped state J12, the first moving state J21, or the second moving state J22. Next, as step S5, the biodetection system 2 determines the threshold D and the detection period Q based on the determined state of vehicle 1.

[0066] Next, in step S6, the biodetection system 2 starts detecting the biological body H using the biodetection unit 3. Then, in step S7, the biodetection system 2 compares the obtained biodetection level L with the threshold D to determine whether or not there is a biological body H in the vehicle compartment 10. If a biological body H is detected, in step S8, the biodetection system 2 issues an alarm in the alarm unit 5 stating that "a biological body H has been left behind," and then returns to the startup waiting state. Conversely, if no biological body H is detected, the biodetection system 2 returns to the startup waiting state without issuing an alarm in the alarm unit 5.

[0067] This method makes it less likely for package B to be mistakenly identified as biometric H, and effectively suppresses false alarms. As a result, a highly user-friendly biometric detection system 2 is obtained.

[0068] Furthermore, the biometric detection system 2 continues to update the state of vehicle 1 even after step S6, and if the state of vehicle 1 changes before determining the presence or absence of a biological organism H (before the detection period Q ends), it may promptly terminate biometric detection and restart biometric detection from step S5 based on the latest state of vehicle 1. Also, for example, in this embodiment, biometric detection is started after determining the threshold D and detection period Q, but it is not limited to this, and for example, as shown in Figure 10, biometric detection may be performed before determining the threshold D and detection period Q, that is, in parallel with the work of determining the state of vehicle 1.

[0069] The biodetection system 2 has been described above. As mentioned above, this biodetection system 2 is a biodetection system that detects living organisms H inside the passenger compartment 10 of a vehicle 1, and comprises a biodetection unit 3 that detects living organisms H inside the passenger compartment 10, and a position change detection unit 4 that detects changes in the position of the vehicle 1. The biodetection unit 3 changes the conditions for detecting living organisms H based on the detection results of the position change detection unit 4. With this configuration, it is possible to detect living organisms H while taking into account luggage B inside the passenger compartment 10. Therefore, it becomes difficult to mistakenly detect vibrating luggage B as living organisms H, and false alarms can be effectively suppressed. As a result, the biodetection system 2 has high usability.

[0070] Furthermore, as mentioned above, the biodetection unit 3 generates a biodetection level L, which is used as a biodetection value to determine the presence or absence of a bio-body H, based on the reflected wave Rw (radio waves reflected by an object), and determines the presence or absence of a bio-body H by comparing the biodetection level L with a threshold D. With this configuration, the presence or absence of a bio-body H can be determined with high accuracy.

[0071] Furthermore, as mentioned above, the biodetection unit 3 changes the threshold D based on the detection result of the position change detection unit 4. With this configuration, the conditions for detecting the bio-body H can be easily changed.

[0072] Furthermore, as mentioned above, the biometric detection unit 3 determines whether the vehicle 1 is in a stopped state J1 or in a moving state J2 based on the detection result of the position change detection unit 4, and sets the threshold D higher than that for the stopped state J1 when the vehicle 1 is in the moving state J2. With this setting, false alarms in the moving state J2 can be effectively suppressed.

[0073] Furthermore, as mentioned above, the biodetection unit 3 determines whether the stopped state J1 is the first stopped state J11 or the second stopped state J12, in which the vehicle 1 is more unstable than in the first stopped state J11. If it is the second stopped state J12, the threshold D is set higher than in the first stopped state J11 and lower than in the moving state J2. With such settings, false alarms in the second stopped state J12 can be effectively suppressed.

[0074] Furthermore, as mentioned above, the biological detection unit 3 changes the detection period Q for detecting the biological body H based on the detection result of the position change detection unit 4. With this configuration, the conditions for detecting the biological body H can be easily changed.

[0075] Furthermore, as mentioned above, the biometric detection unit 3 determines whether the vehicle 1 is in a stopped state J1 or in a moving state J2 based on the detection result of the position change detection unit 4, and sets the detection period Q to be longer than that for the stopped state J1 when the vehicle 1 is in a moving state J2. With this setting, false alarms in the moving state J2 can be effectively suppressed.

[0076] Furthermore, as mentioned above, the biodetection unit 3 determines whether the stopping state of the position change detection unit 4 is the first stopping state J11 or the second stopping state J12, in which the vehicle 1 is more unstable than in the first stopping state J11. If it is the second stopping state J12, the detection period Q is set to be longer than the first stopping state J11 and shorter than the moving state J2. With such settings, false alarms in the second stopping state J12 can be effectively suppressed.

[0077] Furthermore, as mentioned above, the biodetection method using the biodetection system 2 is a biodetection method for detecting a living person H inside the passenger compartment 10 of the vehicle 1, and the conditions for detecting the living person H are changed based on the change in the position of the vehicle 1. With this configuration, it is possible to detect the living person H while taking into account the luggage B inside the passenger compartment 10. Therefore, it becomes less likely to mistakenly detect the vibrating luggage B as a living person H, and false alarms can be effectively suppressed. As a result, the biodetection system 2 has high usability.

[0078] Although the biodetection system and biodetection method of the present invention have been described above based on the illustrated embodiments, the present invention is not limited thereto, and the configuration and steps of each part can be replaced with any configuration or step having a similar function. Furthermore, any other configuration or step may be added to the present invention.

[0079] Furthermore, in the embodiment described above, the state of the vehicle 1 is distinguished into four states: a first stopped state J11, a second stopped state J12, a first moving state J21, and a second moving state J22. However, the number of states of the vehicle 1 is not particularly limited and may be two, three, or five or more. [Explanation of Symbols]

[0080] 1...Vehicle, 10...Vehicle compartment, 2...Biometric detection system, 3...Biometric detection unit, 31...Transmitting antenna, 321...Receiving antenna, 322...Receiving antenna, 323...Receiving antenna, 33...Control unit, 331...Processor, 332...Memory, 34...Transmitting unit, 341...Pulse signal generation unit, 342...Local oscillator, 343...Multiplier, 35...Receiving unit, 351...Multiplier, 352...Multiplier, 353...π / 2 shifter, 354...RF switch, 36...Processing unit, 361...Generation unit, 362...Determination unit, 4...Position change detection unit, 5...Alert unit, 6...Drive control unit, 61…Processor, 62…Memory, 9…Communication device, B…Luggage, D…Threshold, D11…Threshold, D12…Threshold, D21…Threshold, D22…Threshold, H…Biological entity, J1…Stopped state, J11…First stopped state, J12…Second stopped state, J2…Moving state, J21…First moving state, J22…Second moving state, L…Biological entity detection level, Q…Detection period, Q11…Detection period, Q12…Detection period, Q21…Detection period, Q22…Detection period, Rw…Reflected wave, S1~S8…Step, Si…In-phase component signal, Sq…Quaternary phase component signal, Tw…Transmitted wave, U…User

Claims

1. A biometric detection system for detecting living organisms inside a vehicle's interior, A biodetection unit for detecting the living body inside the vehicle interior, It includes a position change detection unit that detects changes in the position of the vehicle, The biodetection system is characterized in that the biodetection unit changes the conditions for detecting the living organism based on the detection result of the position change detection unit.

2. The biological detection system according to claim 1, wherein the biological detection unit generates a biological presence / absence determination value used to determine the presence or absence of a biological being based on radio waves reflected by an object, and determines the presence or absence of a biological being by comparing the biological presence / absence determination value with a threshold value.

3. The biodetection system according to claim 2, wherein the biodetection unit changes the threshold based on the detection result.

4. The biometric detection unit determines, based on the detection result, whether the vehicle is in a stopped state or in a moving state. The biological detection system according to claim 3, wherein the threshold is set higher than that for the stopped state when the system is in motion.

5. The biometric detection unit further determines whether the stopped state is a first stopped state or a second stopped state in which the vehicle is more unstable than the first stopped state. The biological detection system according to claim 4, wherein, in the second stopped state, the threshold is set higher than in the first stopped state and lower than in the moving state.

6. The biological detection system according to claim 2, wherein the biological detection unit changes the detection period for detecting the biological organism based on the detection result.

7. The biometric detection unit determines, based on the detection result, whether the vehicle is in a stopped state or in a moving state. The biological detection system according to claim 6, wherein the detection period is set to be longer than that of the stopped state when the system is in motion.

8. The biometric detection unit further determines whether the stopped state is a first stopped state or a second stopped state in which the vehicle is more unstable than the first stopped state. The biological detection system according to claim 7, wherein, in the second stopped state, the detection period is set to be longer than in the first stopped state and shorter than in the moving state.

9. A biodetection method for detecting living organisms inside a vehicle's interior, A method for detecting a living organism, characterized by changing the conditions for detecting the living organism based on the change in the position of the vehicle.

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