WO2021106025A1 - 位置検出装置及び位置検出方法 - Google Patents

位置検出装置及び位置検出方法 Download PDF

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Publication number
WO2021106025A1
WO2021106025A1 PCT/JP2019/045896 JP2019045896W WO2021106025A1 WO 2021106025 A1 WO2021106025 A1 WO 2021106025A1 JP 2019045896 W JP2019045896 W JP 2019045896W WO 2021106025 A1 WO2021106025 A1 WO 2021106025A1
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WIPO (PCT)
Prior art keywords
moving body
search range
position detection
optical
unit
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
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PCT/JP2019/045896
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English (en)
French (fr)
Japanese (ja)
Inventor
侑真 松田
智之 樋野
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NEC Corp
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NEC Corp
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Publication date
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Priority to JP2021560760A priority Critical patent/JP7201102B2/ja
Priority to US17/778,561 priority patent/US12196605B2/en
Priority to PCT/JP2019/045896 priority patent/WO2021106025A1/ja
Publication of WO2021106025A1 publication Critical patent/WO2021106025A1/ja
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
    • G01H9/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
    • G01H9/004—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means using fibre optic sensors
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
    • G01H9/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
    • G01H9/004—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means using fibre optic sensors
    • G01H9/006—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means using fibre optic sensors the vibrations causing a variation in the relative position of the end of a fibre and another element
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B11/00—Measuring arrangements characterised by the use of optical techniques
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/353—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre
    • G01D5/35338—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre using other arrangements than interferometer arrangements
    • G01D5/35354—Sensor working in reflection
    • G01D5/35358—Sensor working in reflection using backscattering to detect the measured quantity
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/353—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre
    • G01D5/35338—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre using other arrangements than interferometer arrangements
    • G01D5/35354—Sensor working in reflection
    • G01D5/35358—Sensor working in reflection using backscattering to detect the measured quantity
    • G01D5/35361—Sensor working in reflection using backscattering to detect the measured quantity using elastic backscattering to detect the measured quantity, e.g. using Rayleigh backscattering

Definitions

  • the present invention relates to a position detection device and a position detection method, and more particularly to a position detection device and a position detection method of a moving body using optical fiber sensing.
  • Optical fiber sensing is a technology that uses an optical fiber as a sensor for vibration, sound, distortion, or temperature. Optical fiber sensing is used in areas such as intrusion detection in important facilities, traffic flow monitoring of automobiles, and leakage detection of pipelines. Furthermore, the application of optical fiber sensing to systems that monitor the inside of buildings is being studied. One of the applications of optical fiber sensing to monitor the inside of a building is to monitor the position of a moving object (for example, a person).
  • optical fiber sensing can be used as a technique for complementing the blind spot of the camera.
  • Optical fiber sensing is also useful for monitoring places where the camera cannot be used for privacy protection or where the image quality of the camera deteriorates due to insufficient lighting.
  • An optical fiber cable containing an optical fiber (hereinafter referred to as an "optical cable") is used for monitoring a building by optical fiber sensing.
  • an optical cable is laid according to the movement path of the moving body.
  • Patent Document 1 describes an optical fiber sensor system that detects strain and displacement corresponding to a load applied to a structure. Further, Patent Document 2 describes an intrusion detection system that detects an intruder by an optical fiber installed in an orbit.
  • An object of the present invention is to provide a technique for solving a problem that the detection accuracy of the position of a moving body may be lowered in a position detection system using an optical fiber sensor.
  • the position detection device of the present invention detects a transmitting means that sends an optical pulse to an optical transmission line laid along a moving path of a moving body and backward scattered light generated in the optical transmission line in response to the optical pulse. Based on the detection means to be detected, the data processing means for calculating the intensity of the backward scattered light and the generation position of the backward scattered light, the storage means for storing the processing result of the data processing means, and the moving range of the moving body.
  • the search range deriving means for deriving the search range of the position of the moving body and the generation position where the fluctuation of the intensity within the search range becomes the maximum value are extracted, and the extracted generation position is stored in the storage means. It includes a maximum value extraction means for causing the light to be generated, and an output means for outputting the result of the extraction in association with the position of the moving body.
  • the position detection method of the present invention sends an optical pulse to an optical transmission line laid along a moving path of a moving body, detects backward scattered light generated in response to the optical pulse in the optical transmission line, and describes the above.
  • the intensity of the backward scattered light and the generation position of the backward scattered light are calculated, the search range of the position of the moving body is derived based on the moving range of the moving body, and the fluctuation of the intensity within the search range is the maximum value. This includes extracting the generation position to be generated and outputting the result of the extraction in association with the position of the moving body.
  • the recording medium of the present invention detects a procedure of sending an optical pulse to an optical transmission line laid along a moving path of a moving body to a computer, and detecting backward scattered light generated in the optical transmission line in response to the optical pulse.
  • a program for executing the procedure of extracting the number of times the occurrence position where the fluctuation of the intensity becomes the maximum value and the procedure of outputting the result of the extraction in association with the position of the moving body is recorded.
  • the present invention can suppress a decrease in the detection accuracy of the position of a moving body in a position detection system using an optical fiber sensor.
  • FIG. 1 is a block diagram showing a configuration example of the position detection system 10 according to the first embodiment of the present invention.
  • the position detection system 10 detects the position of the moving body by optical fiber sensing.
  • the position detection system 10 includes an optical cable 11 and a position detection device 12.
  • the optical cable 11 is a cable in which at least one optical fiber is stored.
  • the vibration of the building caused by the movement of the moving body is transmitted to the optical cable 11.
  • the position detection system 10 detects the vibration applied to the optical cable 11 and its temporal fluctuation in correspondence with the position where the vibration is applied by using the return light of the optical pulse input to the optical fiber.
  • the position detection device 12 includes a transmission unit 13, a circulator 14, a reception unit 15, and an output unit 18.
  • the receiving unit 15 includes a detector 16, a data processing unit 17, a memory 19, a search range derivation unit 110, an averaging processing unit 111, and a maximum value extraction unit 112.
  • the transmission unit 13 generates an optical pulse, and repeatedly outputs the generated optical pulse to the circulator 14 at predetermined intervals.
  • the circulator 14 is a 3-port optical device. Each port of the circulator 14 is connected to the transmitting unit 13, the receiving unit 15, and the optical cable 11, respectively, by, for example, an optical fiber or an optical waveguide.
  • the circulator 14 outputs the optical pulse output by the transmission unit 13 to the optical cable 11. Further, the circulator 14 outputs the light input from the optical cable 11 to the receiving unit 15.
  • the optical cable 11 is an example of an optical transmission line.
  • the transmission unit 13 serves as a transmission means for transmitting an optical pulse to the optical transmission line. [motion]
  • FIG. 2 is a flow chart of an operation example of the position detection device 12. The operation of the position detection device 12 will be described with reference to FIGS. 1 and 2.
  • the optical pulse output by the transmission unit 13 is output to the optical cable 11 via the circulator 14.
  • an optical pulse is input to at least one optical fiber.
  • the circulator 14 outputs the backscattered light returned from the optical cable 11 to the detector 16.
  • the detector 16 converts the detected backscattered light into an analog electric signal, and outputs the electric signal to the data processing unit 17.
  • the detector 16 is a photoelectric conversion element, for example, a photodiode.
  • the detector 16 serves as a detection means for detecting backscattered light generated in response to an optical pulse.
  • the data processing unit 17 converts the input electric signal into a digital signal, and calculates the amount of fluctuation in the light intensity due to the vibration applied to the optical cable 11 and its generation position.
  • the data processing unit 17 is, for example, an electric circuit including an analog-digital conversion circuit and a signal processing circuit.
  • the data processing unit 17 is responsible for data processing means for calculating the intensity of the backscattered light and the position where the backscattered light is generated.
  • the detector 16 detects the backscattered light generated in the optical cable 11. Since backscattered light is generated while the optical pulse propagates through the optical cable 11, the period during which the backscattered light by one pulse is received by the receiving unit 15 is longer than the optical pulse width T. If the transmission time of the optical pulse is T0, the detection time by the detector 16 at a certain point in the backscattered light is T1, and the propagation time inside the position detection device 12 is ignored, the distance to the backscattered light generation position is the transmission time. It can be obtained as half of the light propagation distance between T0 and the detection time T1.
  • the detector 16 continuously transmits light pulses at intervals such that backscattered light is not detected in duplicate in the detector 16.
  • the data processing unit 17 measures the intensity of the backscattered light in relation to the detection time of the backscattered light for each light pulse. As a result, the data processing unit 17 can calculate the fluctuation amount data including the temporal fluctuation amount of the backscattered light intensity in association with the generation position of the backscattered light.
  • the memory 19 stores the calculated fluctuation amount data in association with its generation position for a certain period of time (step S01 in FIG. 2).
  • the initial position of the moving body is stored in the memory 19 as the current position of the moving body.
  • the memory 19 serves as a storage means for storing the processing result of the data processing unit 17.
  • the memory 19 is, for example, a semiconductor memory.
  • the initial position of the moving body is the position of vibration generated when the moving body passes through the starting point (for example, the entrance of the area) of the area where the optical cable 11 is laid.
  • the search range derivation unit 110 derives an area (search range) in which the moving body can move from the current position during the time when the memory 19 accumulates the fluctuation amount data (S02).
  • the administrator of the position detection system 10 may save the moving speed of the moving body in the memory 19 in advance.
  • the search range derivation unit 110 may obtain the search range as the product of the moving speed stored in the memory 19 and the accumulation time of the fluctuation amount data of the memory 19.
  • the search range may be stored in the memory 19 in advance.
  • the search range derivation unit 110 extracts only the fluctuation amount data within the search range from the fluctuation amount data stored in the memory 19 (S03).
  • the search range derivation unit 110 outputs the extracted fluctuation amount data to the averaging processing unit 111.
  • the search range deriving unit 110 serves as a search range deriving means for deriving the search range of the position of the moving body based on the moving range of the moving body.
  • the averaging processing unit 111 In the fluctuation amount data in the search range input from the search range derivation unit 110, the averaging processing unit 111 first scatters backscattered so that the average value M of the intensity of the backscattered light for each predetermined period becomes M1. Add or subtract a certain value to the light intensity. This process is also carried out during other periods within the accumulation time. After that, the averaging processing unit 111 adds or subtracts a constant value to the fluctuation amount for each position so that the average value of the intensity of the backscattered light becomes M2 for each position on the optical cable 11. This operation is called "averaging" (S04). Note that M1 and M2 are arbitrary constants, and can be set to values that can be processed by the averaging processing unit 111 and the maximum value extraction unit 112.
  • the averaging processing unit 111 outputs the averaged fluctuation amount data to the maximum value extraction unit 112.
  • the averaging processing unit 111 is an example of the averaging means.
  • the averaging means has a function of aligning and outputting the average value of the intensities included in the search range.
  • the maximum value extraction unit 112 acquires the position on the optical cable 11 in which the fluctuation amount of the intensity of the backscattered light becomes the maximum value in the averaged fluctuation amount data input from the averaging processing unit 111. (S05). This position may be expressed as a distance from the starting point of the area where the optical cable 11 is laid. Then, the maximum value extraction unit 112 replaces the current position of the moving body stored in the memory 19 with the acquired position (S06). When the current position of the moving body is updated, the memory 19 deletes all the accumulated fluctuation amount data and its generation position, and stores the fluctuation amount data newly calculated by the data processing unit 17 and its generation position. To start.
  • the maximum value extraction unit 112 is an example of the maximum value extraction means.
  • the maximum value extracting means has a function of extracting a position on the optical cable 11 in which the fluctuation of the intensity of the backscattered light within the search range becomes the maximum value, and storing the extracted position in the storage means.
  • the output unit 18 associates the actual position of the moving body with the position on the optical cable 11.
  • the actual position of the moving body can be the position on the floor of the room if the optical cable 11 is laid under the floor of the room.
  • the output unit 18 derives a position in the actual environment from the current position of the moving body on the optical cable 11 stored in the memory 19, and outputs the position to the outside as the position of the moving body.
  • the correspondence between the actual position of the moving body and the position on the optical cable 11 may be stored in the output unit 18 or the memory 19.
  • the output unit 18 is responsible for outputting the extraction result of the maximum value extraction means in association with the position of the moving body.
  • FIG. 3 is a diagram illustrating a situation in which a moving body moves along the optical cable 11.
  • FIG. 4 is a diagram showing an example of fluctuation amount data when vibration is ideally detected.
  • FIG. 5 is a diagram showing an example of fluctuation amount data in an actual case where vibration is detected. 4-4
  • the time and position where the detected fluctuation amount of the light intensity is larger is shown as whiter (brighter).
  • the vertical axis indicates the time
  • the horizontal axis indicates the position on the optical cable 11 with the position detection device 12 as the origin.
  • FIG. 6 and 7 are diagrams for explaining the position detection of the moving body based on the search range.
  • the black circles at positions A and B in FIG. 6 and positions AC in FIG. 7 indicate that the position can be determined as the position of the moving body because the amount of fluctuation is maximum at that position and time.
  • the amount of fluctuation of the position B at the time Tb is smaller than that of the positions A, D, and E.
  • FIG. 6 shows that by limiting the search range, the position B of the moving body at the time Tb can be detected without being affected by the fluctuation amount data of the positions D and E.
  • FIG. 7 shows that the position C of the moving body at the time Tc can be further detected based on the position B detected in FIG.
  • the position detection system 10 limits the search range of the position of the moving body to the range in which the moving body can move within the accumulation time of the fluctuation amount data. Then, the fluctuation amount data accumulated within that time is averaged, and it is determined that the fluctuation that maximizes the fluctuation amount of the intensity of the backscattered light within that range corresponds to the vibration generated by the movement of the moving body. To do. By doing so, it is possible to reduce the influence of vibration strongly detected due to resonance due to, for example, the mounting state of the optical fiber cable or the structure of the building. In addition, the averaging process facilitates comparison of vibration fluctuations.
  • the position detection system 10 of the present embodiment can suppress a decrease in the detection accuracy of the position of the moving body.
  • FIG. 8 shows a block diagram showing a configuration example of the position detection system 20 of the second embodiment.
  • FIG. 9 shows a flow chart of an operation example of the position detection device 12A.
  • the position detection system 20 includes an optical cable 11 and a position detection device 12A.
  • the position detection device 12A includes a transmission unit 13, a circulator 14, a reception unit 15A, and an output unit 18.
  • the receiving unit 15A is different from the receiving unit 15 shown in FIG. 1 in that it does not include the averaging processing unit 111 but includes the threshold value determination unit 113.
  • the configurations and functions of the other components of the position detection system 20 are the same as those of the position detection system 10. Further, the description overlapping with the first embodiment will be omitted as appropriate. [motion] The operation of the position detection device 12A will be described with reference to FIGS. 8 and 9.
  • the optical pulse output from the transmission unit 13 is output to the circulator 14.
  • the circulator 14 outputs the optical pulse transmitted by the transmission unit 13 to the optical cable 11.
  • the circulator 14 outputs the backscattered light returning from the optical cable 11 to the detector 16.
  • the detector 16 converts the detected backscattered light into an analog electric signal, and outputs the electric signal to the data processing unit 17.
  • the data processing unit 17 converts the input electric signal into a digital signal, and calculates the amount of fluctuation in the intensity of the backscattered light due to the vibration applied to the optical cable 11 and the position where the backscattered light is generated.
  • the memory 19 stores the calculated fluctuation amount data in association with its generation position for a certain period of time (step S11 in FIG. 9).
  • the initial position of the moving body is stored in the memory 19 as the current position of the moving body.
  • the search range derivation unit 110 derives an area (search range) in which the moving body can move from the current position during the time when the fluctuation amount data is accumulated (S12), and extracts only the fluctuation amount data within the search range (S12). S13).
  • the derivation of the search range may be obtained as the product of the data accumulation time and the moving speed of the moving body.
  • the maximum value extraction unit 112 acquires the maximum value of the fluctuation amount of the backscattered light intensity and the position on the optical cable 11 corresponding to the maximum value in the extracted fluctuation amount data (S14), and obtains these. Output to the threshold value determination unit 113.
  • the maximum value of the fluctuation amount of the intensity of the backscattered light and the position on the optical cable 11 corresponding to the maximum value are input to the threshold value determination unit 113 from the maximum value extraction unit 112.
  • the threshold value determination unit 113 compares the preset threshold value with the maximum value of the fluctuation amount within the search range (S15).
  • the administrator of the position detection system 20 may store the threshold value in the memory 19. In this case, the threshold value determination unit 113 reads the threshold value from the memory 19. If the maximum value exceeds the threshold value (S15: YES), the threshold value determination unit 113 outputs the position corresponding to the maximum value to the memory 19, and corresponds to the current position of the moving body stored in the memory 19 to the maximum value. Replace with the position to be used (S16).
  • the search range deriving unit 110 expands the search range and repeats the search procedure (S17).
  • the memory 19 deletes all the accumulated fluctuation amount data and its generation position, and newly calculates the fluctuation amount data by the data processing unit 17 and its generation position. Starts to accumulate (S11).
  • the output unit 18 associates the actual position of the moving body with the position on the optical cable 11.
  • the output unit 18 derives a position in the actual environment from the current position of the moving body on the optical cable 11 stored in the memory 19, and outputs the position to the outside as the position of the moving body.
  • FIG. 10 is a diagram illustrating a process of expanding the search range in the positional direction. Similar to FIGS. 3 to 7, the horizontal axis is the position on the optical cable 11 and the vertical axis is the time. In FIG. 10A, since the search range is narrow, the position where the maximum value of the fluctuation amount exceeds the threshold value is not detected. However, by expanding the search range to the point D in the position direction as shown in FIG. 10B, the point D can be determined as the position of the moving body.
  • FIG. 11 is a diagram illustrating a process of expanding the search range in the time direction.
  • FIG. 11 shows an example of expanding the search range in the positional direction
  • the search range may be expanded in the time direction as shown in FIG. 11B in addition to the positional direction.
  • the point C can be determined as the position of the moving body by extending the search range to the time Td.
  • the position detection system 20 of the present embodiment expands the search range and searches for data in which the maximum value exceeds the fluctuation amount. Therefore, in addition to the effect of the position detection system 10, the position detection system 20 moves by expanding the search range even if vibration is not detected within the initial search range due to an increase or decrease in the speed of the moving body. The position of the body can be detected.
  • the position where the fluctuation amount of the intensity of the backscattered light within the search range is maximum is set as the position of the moving body.
  • the number of distinguishable vibrations within the search range may be obtained, the position of the maximum value for each vibration may be extracted, and the position where the next moving position can be found may be used as the current position of the moving body. By doing so, it is possible to monitor the moving body even when a plurality of vibrations are detected within the search range.
  • FIG. 12 shows a block diagram showing a configuration example of the position detection system 30 of the third embodiment.
  • FIG. 13 shows a flow chart of an operation example of the position detection device 12B.
  • the position detection system 30 includes an optical cable 11 and a position detection device 12B.
  • the position detection device 12B includes a transmission unit 13, a circulator 14, a reception unit 15B, and an output unit 18.
  • the receiving unit 15B is different from the receiving unit 15 shown in FIG. 1 in that it includes an identification number assigning unit 120 connected to the memory 19.
  • the configurations and functions of the other components of the position detection system 30 are the same as those of the position detection system 10. Further, the description overlapping with the first embodiment will be omitted as appropriate. [motion] The operation of the position detection system 30 will be described with reference to FIGS. 12 and 13.
  • the optical pulse output from the transmission unit 13 is output to the circulator 14.
  • the circulator 14 outputs the optical pulse transmitted by the transmission unit 13 to the optical cable 11.
  • the circulator 14 outputs the backscattered light returning from the optical cable 11 to the detector 16.
  • the detector 16 converts the detected backscattered light into an analog electric signal, and outputs the electric signal to the data processing unit 17.
  • the data processing unit 17 converts the input electric signal into a digital signal, and calculates the amount of fluctuation in the intensity of the backscattered light due to the vibration applied to the optical cable 11 and the position where the backscattered light is generated.
  • the memory 19 stores the calculated fluctuation amount data in association with its generation position for a certain period of time (step S31 in FIG. 13).
  • the identification number assigning unit 120 issues an identification number.
  • the identification number is a number that can identify a plurality of moving objects. For example, the identification number assigning unit 120 issues an unused identification number in the past each time the moving body passes through the entrance.
  • the memory 19 stores the position of the vibration generated when the moving body passes through the inlet as the current position of the moving body together with the identification number.
  • the search range derivation unit 110 derives a movable area (search range) from the current position of the moving body for each identification number according to the moving speed of the moving body at the time when the data is accumulated (S32), and within the search range. Only the fluctuation amount data of (S33) is extracted.
  • the averaging processing unit 111 performs averaging processing of the fluctuation amount data extracted by the search range deriving unit 110 for each identification number (S33).
  • the averaging process in step S33 is the same as the averaging process in step S04 of FIG.
  • the maximum value extraction unit 112 acquires the position on the optical cable 11 where the fluctuation amount is the largest value in the fluctuation amount data for which the averaging process has been performed for each identification number (S35). Then, the maximum value extraction unit 112 replaces the current position of the moving body corresponding to the identification number stored in the memory 19 with the acquired position (S36).
  • the output unit 18 associates the actual position of the moving body corresponding to the identification number with the position on the optical cable 11.
  • the output unit 18 derives the position in the actual environment from the current position of the moving body on the optical cable 11 stored in the memory 19 for each identification number, and outputs the position to the outside as the position of the moving body.
  • the position detection system 30 of the present embodiment assigns an identification number to the moving body, and can monitor the position change of vibration for each identification number. As a result, the position detection system 30 has the effect of being able to monitor a plurality of moving objects in addition to the effect of the position detection system 10 of the first embodiment.
  • FIG. 14 shows a block diagram showing a configuration example of the position detection system 40 of the fourth embodiment.
  • FIG. 15 shows a flow chart of an operation example of the position detection device 12C.
  • the position detection system 40 includes an optical cable 11 and a position detection device 12C.
  • the position detection device 12C includes a transmission unit 13, a circulator 14, a reception unit 15C, and an output unit 18.
  • the receiving unit 15C is different from the receiving unit 15B of the position detection system 30 shown in FIG. 12 in that it further includes a pattern learning unit 140 and a pattern determination unit 141.
  • the configurations and functions of the other components of the position detection system 40 are the same as those of the position detection system 30. [motion] The operation of the position detection system 40 will be described with reference to FIGS. 14 and 15.
  • the optical pulse output from the transmission unit 13 is output to the circulator 14.
  • the circulator 14 outputs the optical pulse transmitted by the transmission unit 13 to the optical cable 11.
  • the circulator 14 outputs the backscattered light returning from the optical cable 11 to the detector 16.
  • the detector 16 converts the detected backscattered light into an analog electric signal, and outputs the electric signal to the data processing unit 17.
  • the data processing unit 17 converts the input electric signal into a digital signal, and calculates the amount of fluctuation in the intensity of the backscattered light due to the vibration applied to the optical cable 11 and the position where the backscattered light is generated.
  • the memory 19 stores the calculated fluctuation amount data in association with its generation position for a certain period of time (step S41 in FIG. 15). Each time the moving body passes through the entrance of the area where the optical cable 11 is laid, the identification number assigning unit 120 issues a number so that the identification number is not the same as the previously issued one. The memory 19 stores the position of the vibration generated when the moving body passes through the inlet as the current position of the moving body together with the identification number issued by the identification number assigning unit 120.
  • the pattern learning unit 140 learns a vibration pattern, which is a distribution of the amount of fluctuation in light intensity due to vibration generated by the movement of a moving body, using the identification number as a label (S42).
  • the search range derivation unit 110 derives a movable range (search range) from the current position of the moving body for each identification number according to the moving speed of the moving body at the time when the data is accumulated (S43), and within the search range. Only the fluctuation amount data of (S44) is extracted.
  • the averaging processing unit 111 performs averaging processing for each identification number in the same manner as in step S34 of FIG. 13 (S45).
  • the maximum value extraction unit 112 extracts, for each identification number, the position on the optical cable 11 where the fluctuation amount is maximum in the fluctuation amount data extracted by the search range derivation unit 110, and the vibration pattern including the fluctuation amount. (S46).
  • the pattern determination unit 141 estimates the identification number of the extracted vibration pattern in comparison with the learning result (S47), and compares the estimated identification number with the identification number of the moving object being processed (S48). When the identification number being processed and the estimated identification number match, the current position of the moving body stored in the memory 19 is replaced with the position on the optical cable 11 that maximizes the amount of fluctuation in step S46 (S49). If these do not match, the maximum value extraction unit 112 extracts the position on the optical cable 11 where the fluctuation amount is the next largest value and the vibration pattern including the fluctuation amount (S50), and the pattern determination unit 141 again extracts the vibration pattern. Make a judgment (S47).
  • the output unit 18 associates the actual position of the moving body corresponding to the identification number with the position on the optical cable 11.
  • the output unit 18 derives the position in the actual environment from the current position of the moving body on the optical cable 11 stored in the memory 19 for each identification number, and outputs the position to the outside as the position of the moving body.
  • the position detection system 40 of the fourth embodiment can monitor the position change of vibration by a plurality of moving bodies for each moving body by learning the pattern of vibration generated by the movement of the moving body. Therefore, in addition to the effect of the position detection system 30 of the third embodiment, the position detection system 40 can monitor complicated movements such as collision, approach and intersection of a plurality of moving objects.
  • the server room 160 is a raised floor, and the server rack 161 is installed on the floor of the server room.
  • the wiring between the server racks 161 is stored on the back surface of the server rack 161 and under the floor of the server room 160.
  • an optical cable 11 is laid under the floor of the area where visitors to the server room 160 can enter.
  • a position detection device 12D is connected to one end of the optical cable 11.
  • FIG. 17 shows a block diagram showing the configuration of the position detection system 50 of the present embodiment.
  • FIG. 18 shows a flow chart of an operation example of the position detection device 12D.
  • the position detection system 50 includes an optical cable 11 and a position detection device 12D.
  • the position detection device 12D includes a transmission unit 13, a circulator 14, a reception unit 15D, and an output unit 18.
  • the receiving unit 15D further includes an area monitoring unit 170 and an ID acquisition unit 172 as compared with the receiving unit 15 of the position detection system 10 shown in FIG. [motion]
  • the operation of the position detection system 50 in this embodiment will be described with reference to FIGS. 16 and 17.
  • the optical pulse output from the transmission unit 13 is output to the circulator 14.
  • the circulator 14 outputs the optical pulse transmitted by the transmission unit 13 to the optical cable 11.
  • the circulator 14 outputs the backscattered light returning from the optical cable 11 to the detector 16.
  • the detector 16 converts the detected backscattered light into an analog electric signal, and outputs the electric signal to the data processing unit 17.
  • the data processing unit 17 converts the input electric signal into a digital signal, and calculates the amount of fluctuation in the intensity of the backscattered light due to the vibration applied to the optical cable 11 and the position where the backscattered light is generated.
  • the memory 19 stores the calculated fluctuation amount data in association with its generation position for a certain period of time (step S51 in FIG. 18).
  • the memory 19 acquires and stores the position of the vibration generated when the visitor enters the server room 160 as an initial position.
  • the ID acquisition unit 172 calculates the ID (identification, identification information) of the visitor, the position of the server owned by the visitor, and the route to the server (S52).
  • the administrator of the server room 160 may store the ID of the visitor and the position of the server owned by the visitor corresponding to the ID in the memory 19 in association with each other. In this case, the ID acquisition unit 172 reads the position of the server corresponding to the ID of the visitor from the memory 19.
  • the ID acquisition unit 172 calculates the route from the entrance of the server room 160 to the server based on the position of the read server, and displays the information of the visitor's ID, the position of the corresponding server, and the route to the server in the area. Output to the monitoring unit 170.
  • the search range derivation unit 110 derives a range (search range) that can be moved by the moving speed of the moving body at the time when the data is accumulated from the current position of the visitor (S53), and only the fluctuation amount data within the search range. Is extracted (S54).
  • the averaging processing unit 111 performs averaging processing of the fluctuation amount data within the search range (S55).
  • the averaging process of step S55 is the same as the averaging process of step S04 of FIG. 2 of the first embodiment.
  • the maximum value extraction unit 112 acquires the position on the optical cable 11 where the fluctuation amount is the largest value among the fluctuation amount data that has undergone the averaging process (S56), and the current number of visitors stored in the memory 19 is present. The position is replaced with the acquired position (S57).
  • the area monitoring unit 170 monitors whether or not the current position of the visitor is on the route calculated by the ID acquisition unit (S58). Furthermore, it may be monitored whether the visitor is stopped in front of a server other than the owning server. When the visitors are not on the route, the output unit 18 issues an alarm (S59). The output unit 18 may issue an alarm even when the visitor is stopped in front of a server other than the owned server.
  • the position detection system 50 determines whether or not the movement route in the server room of the visitor associated with the ID of the visitor matches the position detected by the position detection system 50. By providing such a configuration, the position detection system 50 can detect suspicious movements of visitors in addition to the effects of the first embodiment.
  • FIG. 19 is a block diagram showing a configuration example of the position detection device 60 according to the sixth embodiment of the present invention.
  • the position detection device 60 is connected to an optical transmission line 61 laid along the movement path of the moving body.
  • the optical transmission line 61 is, for example, an optical cable in which an optical fiber is housed.
  • the position detection device 60 uses the backward scattered light generated in response to the optical pulse input to the optical transmission path 61 to measure the vibration applied to the optical transmission path 61 and its temporal fluctuation at the position where the vibration is applied. Detect in correspondence with.
  • the position detection device 60 includes a transmission unit 13, a reception unit 15E, and an output unit 18.
  • the receiving unit 15E includes a detector 16, a data processing unit 17, a memory 19, a search range derivation unit 110, and a maximum value extraction unit 112.
  • FIG. 20 is a flow chart of an operation example of the position detection device 60. The operation of the position detection device 60 will be described with reference to FIGS. 19 and 20.
  • the optical pulse output from the transmission unit 13 is output to the optical transmission line 61.
  • backscattered light is generated in response to an optical pulse.
  • the backscattered light returning from the optical transmission line 61 is detected by the detector 16.
  • the detector 16 converts the detected backscattered light into an analog electric signal, and outputs the electric signal to the data processing unit 17.
  • the data processing unit 17 converts the input electric signal into a digital signal, and calculates the amount of fluctuation in the intensity of backscattered light and the position where it is generated.
  • the memory 19 stores the calculated fluctuation amount data in association with the generation position (step S61 in FIG. 20).
  • the search range derivation unit 110 derives an area (search range) in which the moving body can move from the current position during the time when the fluctuation amount data is accumulated (S62), and extracts the fluctuation amount data within the search range (S63). ).
  • the search range derivation unit 110 outputs the extracted fluctuation amount data to the maximum value extraction unit 112.
  • the maximum value extraction unit 112 extracts the position on the optical cable 11 where the fluctuation amount of the intensity of the backscattered light is maximum in the fluctuation amount data (S64). This position may be expressed as a distance from the starting point of the area where the optical cable 11 is laid. Then, the maximum value extraction unit 112 replaces the current position of the moving body stored in the memory 19 with the acquired position (S65).
  • the output unit 18 outputs the extraction result of the position in the maximum value extraction unit 112 in association with the position of the moving body.
  • the position detection device 60 limits the search range of the position of the moving body to the range in which the moving body can move. Then, it is determined that the fluctuation that maximizes the fluctuation amount of the intensity of the backscattered light within that range corresponds to the vibration generated by the movement of the moving body. By doing so, it is possible to reduce the influence of vibration strongly detected due to resonance due to, for example, the mounting state of the optical fiber cable or the structure of the building.
  • the position detection device 60 of the present embodiment can suppress a decrease in the detection accuracy of the position of the moving body.
  • each embodiment may be combined.
  • the configuration of the receiving unit 15A of the second embodiment including the threshold value determination unit 113 instead of the averaging processing unit 111 may be applied to the receiving unit of the third to fifth embodiments.
  • the receiving unit 15A of the second embodiment may include the averaging processing unit 111 included in the other embodiment.
  • the function of the position detection device of each embodiment may be realized by executing a program by a computer (including a logical device and an arithmetic unit).
  • the function of the position detection device may be realized by using an arithmetic unit for the data processing unit 17 and executing the program stored in the memory 19 by the data processing unit 17.
  • the program may be stored and distributed on a computer-readable and non-temporary recording medium such as a flexible disk or a magnetic disk, or may be distributed to a position detection device via a network.
  • the mode in which the movement of the moving body is monitored by the optical cable 11 capturing the vibration generated by the movement of the moving body is shown.
  • the movement may be monitored by capturing the sound generated by the movement of the moving body.
  • the position detecting device may detect the position where the vibration occurs by using scattered light other than Rayleigh scattering.
  • the mode of monitoring the movement of the moving body in the building is shown.
  • the optical cable 11 outside the building it is possible to monitor the moving body outside the building.
  • a transmission means that sends an optical pulse to an optical transmission line laid along the movement path of a moving body, and A detection means for detecting backscattered light generated in response to the optical pulse in the optical transmission line, and A data processing means for calculating the intensity of the backscattered light and the generation position of the backscattered light, and A storage means for storing the processing result of the data processing means and A search range deriving means for deriving a search range for the position of the moving body based on the moving range of the moving body, and a search range deriving means.
  • a maximum value extraction means that extracts the generation position where the fluctuation of the intensity within the search range becomes the maximum value and stores the extracted generation position in the storage means.
  • An output means that outputs the result of the extraction in association with the position of the moving body, and A position detector comprising.
  • Appendix 2 The position detection device according to Appendix 1, wherein the search range is a range in which the moving body can move from the current position within a predetermined time.
  • an identification number assigning means for assigning different identification numbers to the plurality of the moving bodies is provided.
  • the maximum value extracting means extracts the generation position of a plurality of the moving bodies based on the identification number, and stores the extracted generation position in the storage means in association with the identification number.
  • the position detection device according to Appendix 1 or 2.
  • the maximum value extracting means extracts the generation position based on the output from the averaging means.
  • the position detecting device according to any one of Supplementary note 1 to 3.
  • a threshold value determining means for expanding the search range in the position direction of the optical transmission line based on the result of comparison between the maximum value and the first threshold value is further provided.
  • the position detecting device according to any one of Supplementary note 1 to 4.
  • a threshold value determination means for expanding the search range in the time direction based on the result of comparison between the maximum value and the second threshold value is further provided.
  • the position detecting device according to any one of Appendix 1 to 5.
  • Appendix 7 Any of Appendix 1 to 6, further comprising a circulator that outputs the optical pulse input from the optical transmission means to the optical transmission line and outputs the backward scattered light input from the optical transmission line to the detection means.
  • An optical pulse is sent to an optical transmission line laid along the moving path of a moving body to send an optical pulse.
  • the backscattered light generated in response to the optical pulse in the optical transmission line is detected.
  • the intensity of the backscattered light and the generation position of the backscattered light are calculated.
  • a search range for the position of the moving body is derived based on the moving range of the moving body.
  • the generation position where the fluctuation of the intensity within the search range becomes the maximum value is extracted, and the occurrence position is extracted.
  • the result of the extraction is output in association with the position of the moving body.
  • Position detection method is used to detect a search range for the position of the moving body.
  • Appendix 10 The position detection method according to Appendix 9, wherein the search range is a range in which the moving body can move from the current position within a predetermined time.
  • the search range is expanded in the positional direction of the optical transmission line based on the result of comparison between the maximum value and the first threshold value.
  • the position detection method according to any one of Appendix 9 to 12.
  • the present invention can be applied to monitoring moving objects inside and outside a building.
  • Position detection system 11 Optical cable 12, 12A, 12B, 12C, 12D, 60 Position detection device 13 Transmitter 14 Circulator 15, 15A, 15B, 15C, 15D, 15E Receiver 16 Detector 17 Data processing unit 18 Output unit 19 Memory 61 Optical transmission line 110 Search range derivation unit 111 Average processing unit 112 Maximum value extraction unit 113 Threshold judgment unit 120 Identification number assignment unit 140 Pattern learning unit 141 Pattern judgment unit 160 Server room 161 Server rack 170 Area monitoring unit 172 ID acquisition unit

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Length Measuring Devices By Optical Means (AREA)
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PCT/JP2019/045896 2019-11-25 2019-11-25 位置検出装置及び位置検出方法 Ceased WO2021106025A1 (ja)

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