Object detector

Abstract

To provide an object detector and a method for detecting an object that can determine the boarding state of a passenger in a vehicle without attaching a dedicated device, and a method for detecting an object.SOLUTION: The object detector includes: a radio wave sending unit having a plurality of sending antennas arranged in one place of a closed space and emitting a sending wave by each sending antenna; a radio wave receiving unit having a plurality of receiving antennas arranged in another place of the closed space and receiving the sending wave by each receiving antenna; a radio wave intensity information acquisition unit for acquiring radio wave intensity information showing the radio wave intensity of the sending wave emitted from each sending antenna at each receiving antenna; and a detection unit for detecting an object in the closed space on the basis of the radio wave intensity shown by the radio wave intensity information and a predetermined reference intensity.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an apparatus for detecting the position of an object. [Background technology]

[0002] In recent years, seating sensors that determine where a passenger is seated in an automobile, etc., have become widespread. For example, seating sensors using pressure-sensitive switches or the like built into the seat and passenger detection devices using an in-car camera are widely known.

[0003] Also, for example, Patent Document 1 discloses an occupant detection device that determines whether an occupant is sitting on a seat by measuring the distance between the distance sensor and the back of each seat by providing a distance sensor on the dashboard or the back of the front seat facing the seat inside the automobile. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2010-214981 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, installing an in-car camera or providing a sensor on each seat to determine the position of passengers in the car requires a dedicated device, and may require a large cost and labor for installation and maintenance. Also, taking pictures of the inside of the car using an in-car camera or the like may cause discomfort to passengers. Also, if the in-car camera is installed at the front of the car, the information of passengers in the back seats is hidden by the shadow of the front seats, making it difficult to grasp the passengers' riding status, and this may require the installation of multiple cameras.

[0006] Furthermore, in recent years, networking has been promoted in conference rooms, automobiles, and the like, and the installation of wireless communication devices such as Wi-Fi in rooms and automobiles has become widespread.

[0007] The present invention has been made in consideration of the above-mentioned points, and has an object to provide an object detection device that can appropriately determine the riding state of an occupant in a space. [Means for solving the problem]

[0008] The invention described in claim 1 is characterized by having a radio wave transmitting unit having a plurality of transmitting antennas arranged at one location in a closed space and transmitting a transmission wave through each of the plurality of transmitting antennas, a radio wave receiving unit having a plurality of receiving antennas arranged at another location in the closed space and receiving the transmission wave through each of the plurality of receiving antennas, a radio wave strength information acquiring unit acquiring radio wave strength information indicating the radio wave strength of each of the transmission waves transmitted from each of the plurality of transmitting antennas at each of the plurality of receiving antennas, and a detection unit detecting an object within the closed space based on the difference between the radio wave strength indicated by the radio wave strength information and a predetermined reference strength.

[0009] The invention described in claim 6 is an object detection method in which an object detection device having a radio wave transmitting unit with multiple transmitting antennas and a radio wave receiving unit with multiple receiving antennas detects an object in a closed space, characterized in having a radio wave strength information acquisition step of acquiring radio wave strength information indicating the radio wave strength of each of the transmission waves emitted from each of the multiple transmitting antennas at each of the multiple receiving antennas, and a detection step of detecting an object in the closed space based on the difference between the radio wave strength indicated by the radio wave strength information and a predetermined reference strength.

[0010] The invention described in claim 7 is an object detection program executed by an object detection device equipped in a computer, the object detection program including: a program for detecting an object from a plurality of transmitting antennas; a program for detecting an object from a plurality of transmitting antennas; The method is characterized by executing a radio wave intensity information acquisition step of acquiring radio wave intensity information and a detection step of detecting an object within the closed space based on the difference between the radio wave intensity indicated by the radio wave intensity information and a predetermined reference intensity. [Brief description of the drawings]

[0011] [Figure 1] 1 is a top view of the interior of a passenger compartment of an automobile M equipped with an object detection device 10 according to an embodiment of the present application. [Diagram 2] 1 is a functional block diagram of an object detection device 10 according to an embodiment of the present application. [Diagram 3] 2 is a diagram showing a propagation path of radio waves between a transmitting unit 13 and a receiving unit 15 according to an embodiment of the present application. [Figure 4] 1 is a diagram showing a CSI curve measured by the object detection device 10 according to an embodiment of the present application when a cabin CA is unoccupied. [Diagram 5] FIG. 1 is a diagram showing a CSI curve measured by an object detection device according to an embodiment of the present application when a flight crew member is present in cabin CA. [Figure 6] 1 is a diagram showing a difference curve between a CSI curve measured by an object detection device 10 according to an embodiment of the present application when cabin CA is unoccupied and a CSI curve measured when a crew member is on board. [Figure 7] 1 is a diagram showing a determination table for determining data acquired by an object detection device 10 according to an embodiment of the present application and a riding state of a passenger. [Figure 8] 1 is a determination flow RT1 for determining the riding state of a passenger by the object detection device 10 according to an embodiment of the present application. [Figure 9] 1 is a diagram showing an example of a determination table used to determine the riding state of a passenger in the object detection device 10 according to an embodiment of the present application. FIG. [Figure 10] 13 is a generation flow RT2 for generating a decision table for the object detection device 10 according to the embodiment of the present application. [Figure 11] 11 is a determination condition change flow RT3 for changing the determination condition depending on whether or not the occupant is in a vehicle as determined by the object detection device 10 according to the embodiment of the present application. [Figure 12] 11 is a determination condition change flow RT4 for changing the determination condition depending on whether or not the occupant is in a vehicle as determined by the object detection device 10 according to the embodiment of the present application.

[0012] The present invention will be described in detail below with reference to the embodiments. EXAMPLES

[0013] 1 is a top view of a passenger compartment CA of an automobile M equipped with an object detection device 10 according to an embodiment of the present application. For ease of understanding, the roof and door panels of the automobile M are not shown.

[0014] The object detection device 10 is an object detection device that determines the passenger status or baggage placement status in the passenger compartment CA of the automobile M by propagating radio waves within the passenger compartment CA.

[0015] A driver's seat DS and a passenger seat PS are arranged side by side at the front of the passenger compartment CA of automobile M. In addition, a rear seat RS is arranged behind the passenger compartment CA. When automobile M is being driven, the driver DP sits in the driver's seat DS, and passengers can sit in either the passenger seat PS or the rear seat RS.

[0016] The object detection device 10 is mounted, for example, in the dashboard of the automobile M. The object detection device 10 is configured to be able to transmit radio waves into the passenger compartment CA, and is also configured to be able to receive and acquire the transmitted radio waves.

[0017] The transmission unit 13 as a radio wave transmission unit is communicatively connected to the object detection device 10, and is configured to convert an electrical signal output from the object detection device 10 into a radio wave signal and transmit the signal to the cabin CA. The transmission unit 13 is disposed, for example, in the dashboard at the front of the cabin CA. The transmitter 13 has, for example, a plurality of transmission antennas arranged near the front end of the passenger compartment, specifically, in or on the dashboard, and is capable of transmitting radio waves into the passenger compartment CA using the plurality of transmission antennas.

[0018] The receiving unit 15 as a radio wave receiving unit is communicatively connected to the object detection device 10, and is configured to receive radio wave signals propagating within the cabin CA, convert the radio wave signals into electrical signals, and transmit the electrical signals to the object detection device 10. The receiving unit 15 is disposed, for example, in a trunk room or the like behind the cabin CA. The receiving unit 15 has, for example, multiple receiving antennas disposed near the rear end of the cabin, specifically in the space behind the headrest of the rear seat RS or in the trunk room, and is capable of receiving radio waves transmitted from the transmitting antennas and propagating within the cabin CA using the multiple receiving antennas.

[0019] The transmitter 13 transmits a transmission wave including carrier waves of multiple bands via each of multiple transmission antennas. The receiver 15 receives the transmission waves transmitted via the multiple transmission antennas via each of multiple reception antennas.

[0020] In this embodiment, a case will be described in which the transmitter 13 and receiver 15 equipped with a communication antenna are arranged at the front and rear ends of the passenger compartment CA. However, the arrangement of the transmitter 13 and receiver 15 is not limited to this. The transmitter 13 may be arranged at the rear end of the passenger compartment CA and the receiver 15 may be arranged at the front end of the passenger compartment CA, or the transmitter 13 and receiver 15 may be arranged inside the left and right door panels of the automobile M. Also, only the communication antenna may be arranged at the front and rear ends of the passenger compartment CA and wired to the transmitter 13 and receiver 15. In other words, it is only necessary that the configuration be such that radio waves are transmitted from one end of the passenger compartment CA, propagate within the passenger compartment CA, and can be received at the other end opposite the one end of the passenger compartment.

[0021] In other words, the transmitting unit 13 is disposed at one end of the cabin CA, and the receiving unit 15 is disposed at the other end opposite to the one end of the cabin CA.

[0022] The object detection device 10 is configured to be capable of transmitting and receiving radio waves conforming to the IEEE802.11 communication standard via a transmission unit 13 and a reception unit 15, for example.

[0023] The console 17 is disposed, for example, on an instrument panel in the passenger compartment CA. The console 17 includes a display unit 17A and an operation unit 17B communicably connected to the object detection device 10. The display unit 17A can display the determination result output from the object detection device 10 or an image of an operation reception display to the object detection device 10. The operation unit 17B can transmit an operation instruction to the object detection device 10 by selecting the operation reception display to the object detection device 10 displayed on the display unit 17A. The embodiment of the console 17 is not limited to any embodiment. Specifically, for example, the console 17 may be a touch panel display including a display such as a liquid crystal panel and a touch pad attached to the display surface of the display to receive operations by a human finger or the like, or may be an embodiment including a display such as a liquid crystal panel and an operation unit using push buttons. The console 17 can be replaced with various devices including a display unit and an operation unit such as a mobile terminal.

[0024] 2 is a functional block diagram of an object detection device 10 according to an embodiment of the present application. The object detection device 10 is a device in which an input unit 30, an output unit 20, a display output unit 40, an operation reception unit 50, a storage unit 60, and a control unit 70 cooperate with each other via a system bus 19, for example.

[0025] The output unit 20 is an interface that outputs data to an external device of the object detection device 10. The output unit 20 is connected to the transmission unit 13 arranged in the cabin CA, and can output data to the transmission unit 13. Specifically, for example, the object detection device 10 transmits data via the output unit 20. The communication unit 13 outputs communication data as an electrical signal.

[0026] The transmitter 13 is, for example, a radio wave transmitter having a plurality of transmitting antennas 13A and 13B. The transmitter 13 converts the electrical signal supplied via the output unit 20 into a radio wave signal, and transmits the signal as a radio wave into the cabin CA via each of the transmitting antennas 13A and 13B.

[0027] The receiving unit 15 is, for example, a radio wave receiving device having a plurality of receiving antennas 15A, 15B, and 15C. The receiving unit 15 receives radio waves transmitted from the transmitting antennas 13A and 13B of the transmitting unit 13 into the cabin CA via the receiving antennas 15A, 15B, and 15C. The receiving unit 15 converts the radio wave signals received by the receiving antennas 15A, 15B, and 15C into communication data of an electrical signal and outputs the data.

[0028] The input unit 30 is an interface that acquires data from devices external to the object detection device 10. The input unit 30 is connected to the receiving unit 15 that is arranged in the cabin CA. Specifically, for example, the object detection device 10 acquires communication data in the form of an electrical signal from the receiving unit 15 via the input unit 30.

[0029] The display output unit 40 is an interface that outputs data to an external device of the object detection device 10. The display output unit 40 is connected to the display unit 17A of the console 17 described above, and is capable of outputting images thereto. Specifically, for example, the object detection device 10 outputs, via the output unit, to the display unit 17A, a determination result of determining the onboard state of a crew member and an operation image that serves as an operation acceptance display for operating the object detection device 10.

[0030] The operation reception unit 50 is an interface that receives an operation input signal from an external device. The operation reception unit 50 is connected to the operation unit 17B of the console 17, and can receive a signal indicating an operation received on the operation image by the operation unit 17B.

[0031] The storage unit 60 is configured with, for example, a hard disk device, a solid state drive (SSD), a flash memory, etc., and stores various programs related to generation of transmission data and reception of the transmission data in the object detection device 10. Note that the various programs may be obtained, for example, from another server device or the like via a network (not shown), or may be recorded on a recording medium and read via various drive devices.

[0032] The various programs stored in the storage unit 60 can be transmitted via a network, and can also be recorded on a computer-readable recording medium and transferred. The storage unit 60 can also store data acquired from outside the object detection device 10, for example, communication data acquired from the receiving unit 15. The storage unit 60 can also store data generated inside the object detection device 10.

[0033] The control unit 70 is configured with a CPU (Central Processing Unit) 70A, a ROM (Read Only Memory) 70B, a RAM (Random Access Memory) 70C, etc., and functions as a computer. In the control unit 70, the CPU reads out and executes various programs stored in the ROM and the storage unit 60, thereby realizing various functions.

[0034] The control unit 70 supplies communication data to the transmission unit 13 via the output unit 20 based on a program stored in the storage unit 60. The transmission unit 13 converts the communication data into a radio wave signal and transmits a transmission wave including a plurality of carriers via each of the transmission antennas 13A and 13B.

[0035] The control unit 70 also controls the communication data based on the program stored in the storage unit 60. via the input unit 30. The receiving unit 15 receives the radio wave signals propagating within the cabin CA by each of the receiving antennas 15A, 15B, and 15C, and converts the radio wave signals into communication data of an electric signal. The control unit 70 acquires the communication data of the electric signal via the input unit 30. At this time, the control unit 70 functions as a radio wave intensity information acquisition unit.

[0036] The control unit 70 receives, via each of the multiple receiving antennas 15A, 15B, and 15C, a transmission wave such as PING (hereinafter, sometimes simply referred to as a PING signal) including multiple carriers transmitted from each of the multiple transmitting antennas 13A and 13B, and measures a CSI (Channel. State Information) curve, which is the radio wave intensity of each carrier in each propagation path of the transmission wave. In addition, by measuring the change in the CSI curve before and after the passengers board in the passenger compartment CA of the automobile M, it becomes possible to determine the number of passengers and their boarding positions in the passenger compartment CA. At this time, the control unit 70 functions as a detection unit.

[0037] In other words, the object detection device 10 has a transmitting unit 13 having multiple transmitting antennas arranged at one location in the cabin CA and transmitting radio signals via each of the multiple transmitting antennas, a receiving unit 15 having multiple receiving antennas arranged at other locations in the cabin CA and receiving radio signals via each of the multiple receiving antennas, and a control unit 70 that acquires a CSI curve indicating the radio wave strength of each of the transmission waves transmitted from each of the multiple transmitting antennas at each of the multiple receiving antennas, and detects passengers in the cabin CA based on the difference between the radio wave strength indicated by the CSI curve and a predetermined reference strength.

[0038] Moreover, the radio signal is a radio signal that includes carriers of multiple bands.

[0039] In this embodiment, as described above, the case where the transmitter 13 has two transmitting antennas and the receiver 15 has three receiving antennas will be described. However, the numbers of transmitting antennas and receiving antennas provided in the transmitter 13 and the receiver 15 are not limited to this. Specifically, it is sufficient that a configuration is provided in which a plurality of radio wave propagation paths are obtained between the transmitter 13 and the receiver 15.

[0040] 3 is a diagram showing a propagation path of radio waves between the transmitting unit 13 and the receiving unit 15 according to an embodiment of the present application. As described above, in this embodiment, the transmitting unit 13 has two transmitting antennas, and the receiving unit 15 has three receiving antennas.

[0041] The radio waves are transmitted from the transmitting antennas 13A and 13B via the transmitter 13. The radio waves transmitted from the transmitting antennas 13A and 13B are received by the receiving antennas 15A, 15B, and 15C, respectively, and are supplied to the object detection device 10 via the receiver 15. Therefore, the radio waves transmitted from the transmitting antenna 13A have three propagation paths, namely, a path P1 received by the receiving antenna 15A, a path P2 received by the receiving antenna 15B, and a path P3 received by the receiving antenna 15C. Meanwhile, the radio waves transmitted from the transmitting antenna 13B have three propagation paths, namely, a path P4 received by the receiving antenna 15A, a path P5 received by the receiving antenna 15B, and a path P6 received by the receiving antenna 15C. That is, in this embodiment, the propagation paths of the radio waves of the object detection device 10 have a total of six propagation paths, namely, paths P1 to P6.

[0042] The object detection device 10 measures the radio wave strength of each carrier along the propagation paths of paths P1 to P6 when cabin CA is empty and when crew members are on board, and determines the number of crew members and their boarding positions in cabin CA based on the difference in radio wave strength.

[0043] First, from the CSI curves when the cabin is empty and when the crew is on board, and their difference, A method for determining the number and boarding positions of passengers in a cabin CA will be described.

[0044] FIG. 4 is a diagram showing a CSI curve measured by the object detection device 10 according to the embodiment of the present application when the cabin CA is unoccupied.

[0045] The horizontal axis indicates the carrier number, and the vertical axis indicates the radio wave strength of each of the carrier numbers. The curves in the figure are CSI curves indicating the radio wave strength of each carrier number when the PING signal oscillated by the control unit 70 via the transmission unit 13 is received by the reception unit 15. Each curve also indicates paths P1 to P6, which are the propagation paths between the transmission antennas 13A and 13B and the reception antennas 15A, 15B, and 15C. In this embodiment, a case will be described where the number of radio wave carriers is 30.

[0046] The CSI curve is, for example, obtained by measuring and averaging the radio wave strength of each propagation path and each carrier number at a predetermined time between the transmitting unit 13 and the receiving unit 15. The measurement time of the radio wave strength when acquiring the CSI curve can be set arbitrarily. For example, the measurement time may be set to a fixed predetermined time, or may be set automatically, such as by detecting a change in radio wave strength due to a change in the boarding status in the cabin CA and automatically ending the measurement.

[0047] As shown in Figure 4, the behavior of the CSI curve changes significantly for paths P1 to P6 depending on the driver's seat DS, passenger seat PS, and rear seat RL located in the passenger compartment CA, the positions of the transmitting antenna and receiving antenna, and the directivity of the transmitting antenna and receiving antenna, etc.

[0048] As described above, the CSI curve is a CSI curve that indicates the radio wave strength for each of multiple bands along each of multiple propagation paths of a radio wave signal transmitted via each of multiple transmitting antennas and received via each of multiple receiving antennas.

[0049] FIG. 5 is a diagram showing a CSI curve measured by the object detection device 10 according to the embodiment of the present application when a crew member is present in the cabin CA.

[0050] In this embodiment, a case will be described in which the driver DP is seated only in the driver's seat DS.

[0051] In addition, the CSI curve when the crew is on board is also obtained by measuring and averaging the radio wave strength of each propagation path and each carrier number between the transmitter 13 and the receiver 15 at a predetermined time, as in the case of the CSI curve when no crew is present. The measurement time of the radio wave strength when the CSI curve is obtained can be set arbitrarily. For example, the measurement time may be set to a fixed predetermined time, or may be set automatically, such as by detecting a change in the radio wave strength due to a change in the boarding status in the cabin CA and automatically ending the measurement.

[0052] As shown in FIG. 5, when a passenger boards cabin CA, the propagation conditions of the radio waves between transmitting antennas 13A and 13B and receiving antennas 15A, 15B and 15C change, and the acquired CSI curve also changes.

[0053] 6 is a diagram showing a difference curve between the CSI curves measured by the object detection device 10 according to the embodiment of the present application when the cabin CA is unoccupied and when a passenger is on board. Specifically, this is a difference curve obtained by subtracting the radio wave strength of each carrier number when a passenger is on board from the radio wave strength of each carrier number when the cabin CA is unoccupied by the control unit 70. In other words, the difference curve is the amount of variation in the CSI curve between when the cabin CA is unoccupied and when a passenger is on board.

[0054] The control unit 70 performs the following operations when the cabin CA shown in FIG. 4 and FIG. 5 is empty and when the crew boards the cabin CA. From the CSI curve, the control unit 70 calculates the difference curve shown in Fig. 6. Furthermore, the control unit 70 extracts the numerical values ​​of a predetermined path and a predetermined carrier number from the difference curve, and sets them as acquired data.

[0055] In addition, the control unit 70 compares the acquired data with a determination table pre-recorded in the storage unit 60, and determines the number of crew members and their boarding positions in the cabin CA based on the comparison result.

[0056] FIG. 7 is a diagram showing an example of a determination table for determining the data acquired by the object detection device 10 according to the embodiment of the present application and the riding state of a passenger.

[0057] The upper part of Fig. 7 shows acquired data obtained by extracting the numerical values ​​of a predetermined path and a predetermined carrier number from a difference curve calculated based on the CSI curve when the cabin CA is unoccupied and when a crew member is on board. The lower part of Fig. 7 shows judgment data obtained by extracting the numerical values ​​of the path and carrier number used in the acquired data from a judgment table stored in the memory unit 60.

[0058] When determining the onboard state of the crew member, the control unit 70 extracts the numerical value of a predetermined carrier number from the calculated difference curve. In this embodiment, a case will be described in which numerical values ​​of three carriers, carrier numbers 5, 15, and 25, are extracted.

[0059] Furthermore, the control unit 70 calculates the sum of the absolute values ​​of the extracted carrier numbers for each of the paths P1 to P6. The control unit 70 selects a predetermined number of paths in descending order of the calculated sum of absolute values ​​as the acquired data. In this embodiment, a case will be described where paths P1, P2, and P3 are selected as the acquired data.

[0060] The determination table is recorded in the storage unit 60 and is read out when the control unit 70 determines the boarding state from the acquired data.

[0061] The judgment table records all paths of the differential curves and the numerical values ​​of all carrier numbers for patterns in which passengers may be seated in the passenger compartment CA of automobile M, such as, for example, the driver alone sitting in the driver's seat DS, the driver sitting in the driver's seat DS and a passenger sitting in the passenger seat PS, or the driver sitting in the driver's seat DS and a passenger sitting on the left side of the rear seat RS.

[0062] The control unit 70 compares the acquired data with a determination table pre-stored in the storage unit 60, and determines the onboard status of the crew members in the cabin CA based on the comparison result.

[0063] In this embodiment, the extracted carrier numbers are described as 5, 15, and 25, but the carrier numbers and the number of carrier numbers to be extracted are not limited to these. A predetermined number of carrier numbers may be preset as in this embodiment, or a predetermined number may be automatically extracted from the maximum value, minimum value, and intermediate carrier numbers between the maximum and minimum values ​​of the difference curve, or from the maximum and minimum values. Also, all carrier numbers may be used as the acquired data.

[0064] In this embodiment, the three paths are automatically selected in descending order of the sum of the absolute values ​​of the extracted carrier numbers as the acquired data, but the method and number of paths to be selected are not limited to this. A predetermined path may be set in advance, or the values ​​of all paths may be used as the judgment data.

[0065] However, since the passenger status is determined from the amount of change between the CSI curve when the cabin CA is empty and the CSI curve when passengers are on board, it is preferable to select the curve with the largest difference.

[0066] The control unit 70 compares the acquired data with the recorded judgment table, and searches the judgment table for judgment data having a numerical value of the passenger's on-board status that is the same as the numerical value of the carrier number in each path of the acquired data or that is within a specified numerical range.

[0067] When the boarding state determination data that meets the above conditions is found, the control unit 70 determines that the boarding state is a boarding state in the cabin CA, and displays the determination result on the console 17.

[0068] The conditions under which the acquired data and the judgment data in the judgment table match can be set arbitrarily. The conditions may be preset by the user or the manufacturer, or may be automatically changed depending on the judgment result.

[0069] The result of the determination may be checked against the seat belt fastening status to prompt passengers who are not fastening their seat belts to fasten them. Also, audio settings such as sound field and volume optimization in the cabin cabin may be adjusted depending on the boarding status.

[0070] FIG. 8 shows a determination flow RT1 for determining the riding state of a passenger by the object detection device 10 according to the embodiment of the present application.

[0071] First, the control unit 70 acquires a CSI curve when the passenger compartment CA is unoccupied (step S101). This process may be performed, for example, by confirming that the door lock of the automobile M has been released. This process may not be performed every time. Specifically, this process may be performed before product shipment, every time the door lock is released a predetermined number of times, or every time the object detection device 10 operates for a predetermined period of time, and may be recorded in the storage unit 60 as a reference value for calculating income data. Since the CSI data changes somewhat due to the passenger's movements, breathing, etc. when boarding, it may be observed for a certain period of time and determined to be unoccupied if there is no change.

[0072] Next, as a radio wave intensity information acquisition step, the control unit 70 acquires a CSI curve when a passenger boards the cabin CA (step S102). This process may be performed, for example, by confirming that the engine of the automobile M has started or that the automobile M has started moving.

[0073] Next, the control unit 70 calculates a difference curve by subtracting the CSI curve when the cabin CA is unoccupied from the CSI curve when the cabin CA is unoccupied (step S103). Note that the CSI curve when the cabin CA is unoccupied may be obtained each time the determination flow RT1 is executed as described above, and used to calculate the difference curve, or a reference value obtained in advance and recorded in the storage unit 60 may be read out and used to calculate the difference curve.

[0074] Next, the control unit 70 extracts the numerical value of a predetermined carrier number from the calculated difference curve (step S104).

[0075] Next, the control unit 70 calculates the sum of the absolute values ​​of the numerical values ​​of the specified carrier numbers extracted from the difference curve, and selects a specified number of paths to be used for the judgment data in descending order of the sum of the absolute values, and sets these as the acquired data (step S105).

[0076] Next, the control unit 70 reads out the judgment table recorded in the storage unit 60, and compares the acquired data with the judgment data for the path and the carrier number in the judgment table (step S106).

[0077] Next, as a detection step, the control unit 70 searches the determination data in the determination table for determination data that is the same as the acquired data or that is within a predetermined numerical range, and determines the riding state of the passenger from the determination data that matches the condition (step S107). The judgment result is displayed.

[0078] Through the above processing, it is possible to determine the passenger status from the CSI curve acquired when cabin CA is unoccupied and the CSI curve acquired when passengers are present in cabin CA.

[0079] As described above, the control unit 70 sets the CSI curve when there is no occupant to be detected inside the cabin CA as the reference value.

[0080] Furthermore, as described above, the object detection method of the object detection device 10 is an object detection method in which the object detection device 10, which is equipped with a transmitting unit 13 having a plurality of transmitting antennas 13A and 13B and a receiving unit 15 having a plurality of receiving antennas 15A, 15B, and 15C, detects occupants in cabin CA, and includes a radio wave strength information acquisition step of acquiring a CSI curve indicating the radio wave strength of each of the radio wave signals transmitted from each of the plurality of transmitting antennas 13A and 13B at each of the plurality of receiving antennas 15A, 15B, and 15C, and a detection step of detecting occupants in cabin CA based on the difference between the radio wave strength indicated by the CSI curve and the CSI curve when cabin CA is unoccupied.

[0081] Next, the determination data for determining the number and boarding positions of passengers in the cabin CA will be described.

[0082] FIG. 9 is a diagram showing an example of a determination table used for determining the riding state of a passenger by the object detection device 10 according to the embodiment of the present application.

[0083] As described above, the judgment table is recorded in the storage unit 60, and is read out when the control unit 70 judges the boarding state from the acquired data. The judgment table may be recorded in the storage unit 60 at the time of product shipment, or the data may be generated by a user after product shipment.

[0084] In the judgment table, all paths and all carrier number values ​​of the difference curve of the pattern in which the passenger may be seated in the passenger compartment CA of the automobile M are recorded, such as, for example, only the driver sits in the driver's seat DS, the driver sits in the driver's seat DS and the passenger sits in the passenger seat PS, or the driver sits in the driver's seat DS and the passenger sits on the left side of the rear seat RS. In this embodiment, a case will be described in which all paths and all carrier number values ​​of the difference curve of the pattern in which the passenger may be seated in the passenger compartment CA are recorded in the judgment table. However, the recorded contents of the judgment table are not limited to this. Specifically, for example, a predetermined path and carrier number may be set in advance and only the predetermined path and carrier number values ​​may be recorded. In addition, the maximum value, minimum value, and intermediate carrier numbers between the carrier numbers indicating the maximum value and minimum value of the difference curve, or a predetermined quantity may be automatically selected and recorded from the maximum value and minimum value.

[0085] FIG. 10 shows a generation flow RT2 for generating a decision table for the object detection device 10 according to the embodiment of the present application.

[0086] First, the control unit 70 acquires a CSI curve when the passenger compartment CA is unoccupied (step S201). This process may be performed by, for example, confirming that the door lock of the automobile M has been released.

[0087] Next, the control unit 70 determines whether the seating position of the crew member has been input (step S202). This determination may be made, for example, based on whether the seating state of the crew member has been input in the console 17.

[0088] Next, the control unit 70 acquires a CSI curve when a passenger boards the cabin CA (step S203). This process may be automatically executed after the process of step S202 is executed, or may be executed in response to an instruction operation to start acquisition being input on the console 17.

[0089] Next, the control unit 70 calculates a difference curve by subtracting the CSI curve when a passenger is present in the cabin CA from the CSI curve when the cabin CA is unoccupied (step S204).

[0090] Next, the control unit 70 records the calculated numerical values ​​of each path and each carrier number of the differential curve in the storage unit 60 so as to add them to the judgment table as judgment data.

[0091] By repeatedly executing the above generation flow RT2 as many times as there are possible seating patterns for passengers in cabin CA, it is possible to generate a judgment table for determining the boarding status of passengers when they actually board the aircraft.

[0092] The generation flow RT2 may be performed by the manufacturer before the product is shipped and recorded in the storage unit 60, or the decision table may be generated by the user after the product is shipped.

[0093] Next, a description will be given of feedback of the determination result by the user in a case where the object detection device 10 cannot determine the on-board state of the occupant by comparing the acquired data with the determination table, or in a case where the determined on-board state of the occupant is incorrect.

[0094] FIG. 11 shows a determination flow RT3 in the case where feedback of the determination result of the object detection device 10 according to the embodiment of the present application is performed.

[0095] FIG. 12 shows a determination condition change flow RT4 for changing the determination condition depending on whether or not the occupant is in a vehicle as determined by the object detection device 10 according to the embodiment of the present application.

[0096] The decision flow RT3 in Fig. 11 is similar to the decision flow RT1 shown in Fig. 8, and steps S301 to S306 of the decision flow RT3 in Fig. 11 correspond to steps S101 to S106 of the decision flow RT1 in Fig. 8. Descriptions of overlapping processes in steps S301 to S306 will be omitted.

[0097] In step S306, the control unit 70 reads out the judgment table recorded in the storage unit 60, and compares the acquired data with the judgment data for the path and the carrier number in the judgment table (step S306).

[0098] Next, in FIG. 12, the control unit 70 judges whether the acquired data in the process executed in step S306 in FIG. 11 matches any of the judgment data in the judgment table (step S401).

[0099] If it is determined that the acquired data does not match any of the judgment data in the judgment table (step S401: No), the control unit 70 causes the console 17 to display a message prompting the input of the actual boarding status of the passenger, and determines whether the boarding status has been input in the console 17 (step S402).

[0100] In step S402, if it is not determined that the boarding state is input in the console 17 (step S402: No), the control unit 70 determines that the acquired data does not match the determination data, and ends the determination condition change flow RT4. This determination may be made by detecting that no input has been made to console 17 for a certain period of time, or by displaying an option to execute a cancellation process on console 17 and selecting the cancellation process on console 17.

[0101] Furthermore, in step S402, if it is determined that the actual boarding status has been input on the console 17 (step S402: Yes), the control unit 70 links the numerical values ​​of all paths and all carrier numbers of the acquired differential CSI curve with the data of the boarding status of the passenger input by the user, and records in the storage unit 60 the judgment data of the input boarding status in the judgment table so as to update it to the numerical values ​​of the currently acquired differential CSI curve (step S403). As a result, from the next judgment onwards, the boarding status of the passenger is judged using the updated judgment data. Also, the judgment data may be updated even from the next judgment onwards.

[0102] Also, in step S401, if it is determined that the acquired data matches any of the judgment data in the judgment table (step S401: Yes), the control unit 70 causes the console 17 to display an option for whether the judged boarding status is correct, and determines whether the boarding status has been input as correct in the console 17 (step S404).

[0103] In step S404, if it is determined that the boarding state determined in the console 17 is correct (step S404: Yes), the control unit 70 ends the determination condition change flow RT4.

[0104] Also, in step S404, if the user inputs that the determined boarding status is incorrect (step S404: No), the control unit 70 causes the console 17 to display a message prompting the user to enter the actual boarding status of the passenger, and determines whether the boarding status has been entered in the console 17 (step S405).

[0105] In step S405, when it is determined that the boarding state has not been input by the user (step S405: No), the control unit 70 determines that the acquired data does not match the determination data, and ends the determination condition change flow RT4. Note that this process may be determined by determining that there has been no input to the console 17 for a certain period of time, or by displaying an option to execute a cancellation process on the console 17 and determining that the cancellation process has been selected on the console 17.

[0106] Furthermore, in step S405, if it is determined that the actual boarding status has been input on the console 17 (step S405: Yes), the control unit 70 links the numerical values ​​of all paths and all carrier numbers of the acquired differential CSI curve with the data of the boarding status of the passenger input by the user, and records in the storage unit 60 the judgment data of the input boarding status in the judgment table so as to update it to the numerical values ​​of the currently acquired differential CSI curve (step S406). As a result, from the next judgment onwards, the boarding status of the passenger is judged using the updated judgment data. Also, the judgment data may be updated even from the next judgment onwards.

[0107] Next, the control unit 70 adds an update flag to the erroneously determined determination data of the boarding state, indicating that the data needs to be updated (step S407). Note that the determination data of the boarding state may be temporarily not used for determination until a new CSI curve for the boarding state is acquired after the next determination or until the user newly executes the generation flow RT2 shown in Fig. 10, and then the console 17 may display that the determination data of the boarding state needs to be updated.

[0108] By executing the above process, it is possible to change the determination conditions depending on whether the object detection device 10 determines whether the occupant is in a vehicle, thereby improving the accuracy of determining the occupancy state.

[0109] The determination condition change flow RT4 may be executed immediately after step S306 of the determination flow RT3 shown in FIG. 11, or may be executed when the automobile M is stopped or the engine is stopped.

[0110] Also, the system may be freely switched between a normal mode in which the judgment flow RT1 in Fig. 8 is executed and a feedback mode in which the judgment flow RT3 and judgment condition change flow RT4 in Figs. 11 and 12 are executed. Also, the system may be automatically executed only when the acquired data does not match the judgment data in the judgment table.

[0111] According to this embodiment, it is possible to provide an object detection device capable of determining the riding state of passengers in an automobile without installing a dedicated device on each seat.

[0112] In this embodiment, the object detection device 10 is described, which transmits and receives radio waves by arranging the transmitter 13 and the receiver 15 having multiple antennas at one end and the opposite end in the passenger compartment CA of the automobile M. However, the arrangement of the transmitter 13 and the receiver 15 is not limited to this. For example, the transmitter 13 and the receiver 15 may be an integrated transmitter / receiver device in which the directivities of the multiple antennas respectively have are oriented in opposite directions, and the integrated transmitter / receiver device may be arranged, for example, in the center of the passenger compartment CA.

[0113] In the present embodiment, the object detection device 10 is mounted in the passenger compartment CA of the automobile M and determines in which seat the passenger is seated. However, the object detection device 10 can also be used to detect objects in places other than the passenger compartment of the automobile. Specifically, for example, the object detection device 10 may be installed in a private room such as a conference room to grasp the seating situation and vacant seating situation in the private room. Also, the object detection device 10 may be installed in a restaurant to grasp the vacant seating situation in the restaurant. Also, audio adjustments and the like may be performed using the information on the seating situation or vacant seating situation. Also, the object detection device 10 can be applied to various moving bodies equipped with a passenger compartment, such as a bus, a train, or an airplane.

[0114] In the present embodiment, the object detection device 10 has been described as determining in which seat a passenger is seated. However, the object to be detected is not limited to a person. For example, the object detection device 10 may detect baggage or the like brought into the cabin CA.

[0115] In the present embodiment, the object detection device 10 has been described for acquiring information on the radio wave intensity of the CSI. However, the acquired CSI information is not limited to the radio wave intensity. Specifically, for example, the same thing as in the present embodiment can be realized by using the phase change of the radio wave acquired as the CSI. [Explanation of symbols]

[0116] 10 Object detection device 13 Transmitter 15 Receiving section 17 Console 19 System Bus 20 Output section 30 Input section 40 Display output section 50 Operation reception section 60 Storage section 70 Control section

Claims

[Claim 1] a radio wave transmitting unit having a plurality of transmitting antennas arranged at one location in the closed space and transmitting a transmission wave via each of the plurality of transmitting antennas; a radio wave receiving unit having a plurality of receiving antennas arranged in another portion of the closed space and receiving the transmission wave via each of the plurality of receiving antennas; a radio wave intensity information acquisition unit that acquires radio wave intensity information indicating a radio wave intensity of each of the transmission waves transmitted from each of the plurality of transmission antennas in each of the plurality of reception antennas; and a detection unit that detects an object in the closed space based on a difference between the radio wave intensity indicated by the radio wave intensity information and a predetermined reference intensity.

Images