Detection device and detection method

Abstract

A detection device according to the present invention comprises: a signal output unit that outputs a measurement signal having a frequency component to a target line; a measurement unit that receives a response signal based on the measurement signal and measures the amplitude and / or phase of the received response signal; a calculation unit that calculates an evaluation value on the basis of the measurement result from the measurement unit; and a detection unit that detects the twist angle of the target line on the basis of the evaluation value calculated by the calculation unit.

Description

Detection device and detection method

[0001] This application claims priority from Japanese Patent Application No. 2024-61375, filed April 5, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0002] Patent Document 1 (JP 2023-87978 A) discloses the following conductor strain evaluation method: That is, the conductor strain evaluation method is a method for evaluating strain imparted to a cable having a conductor made of a stranded conductor formed by twisting a plurality of strands when the conductor is subjected to bending and / or twisting operations, in which the resistance value of the conductor that changes over time when the operations are cyclically applied to the cable is measured, and the strain is evaluated based on the fluctuation range of the measured time-series changing resistance value of the conductor.

[0003] JP 2023-87978 A

[0004] The detection device of the present disclosure includes a signal output unit that outputs a measurement signal having a frequency component to a target wire, a measurement unit that receives a response signal based on the measurement signal and measures at least one of the amplitude and phase of the received response signal, a calculation unit that calculates an evaluation value based on the measurement result by the measurement unit, and a detection unit that detects the twist angle of the target wire based on the evaluation value calculated by the calculation unit.

[0005] One aspect of the present disclosure may be realized not only as a detection device including such a characteristic processing unit, but also as a program for causing a computer to execute the steps of such characteristic processing. Furthermore, one aspect of the present disclosure may be realized as a semiconductor integrated circuit that realizes part or all of the detection device, or as a system including the detection device.

[0006] FIG. 1 is a diagram illustrating a configuration of a communication system according to a first embodiment of the present disclosure. FIG. 2 is a diagram illustrating an example of a transmission line used in the communication system according to the first embodiment of the present disclosure. FIG. 3 is a diagram illustrating a configuration of a communication device according to the first embodiment of the present disclosure. FIG. 4 is a diagram illustrating an example of a reflection coefficient calculated by a processing unit in the communication device according to the first embodiment of the present disclosure. FIG. 5 is a diagram illustrating an example of a detection result of the twist angle θ by the processing unit in the communication device according to the first embodiment of the present disclosure. FIG. 6 is a flowchart defining an example of an operation procedure when the communication device according to the embodiment of the present disclosure performs detection processing. FIG. 7 is a diagram illustrating a configuration of a communication system according to a second embodiment of the present disclosure. FIG. 8 is a diagram illustrating an example of a transmission line used in the communication system according to the second embodiment of the present disclosure. FIG. 9 is a diagram illustrating a configuration of a communication device according to the second embodiment of the present disclosure. FIG. 10 is a diagram illustrating an example of a reflection coefficient calculated by a processing unit in the communication device according to the second embodiment of the present disclosure. FIG. 11 is a diagram illustrating an example of a detection result of the twist angle θ by the processing unit in the communication device according to the second embodiment of the present disclosure.

[0007] Conventionally, techniques for predicting the life of a cable have been proposed.

[0008] [Problem to be Solved by the Present Disclosure] Patent Document 1 does not disclose a method for detecting the twist angle of a cable.

[0009] The present disclosure has been made to solve the above-mentioned problems, and its purpose is to provide a detection device and a detection method that are capable of detecting the twist angle of a target wire with higher accuracy.

[0010] Effect of the Present Disclosure According to the present disclosure, the twist angle of a target wire can be detected with higher accuracy.

[0011] [Description of Embodiments of the Present Disclosure] First, the contents of the embodiments of the present disclosure will be listed and described. (1) A detection device according to an embodiment of the present disclosure includes a signal output unit that outputs a measurement signal having a frequency component to a target wire, a measurement unit that receives a response signal based on the measurement signal and measures at least one of the amplitude and the phase of the received response signal, a calculation unit that calculates an evaluation value based on the measurement result by the measurement unit, and a detection unit that detects the twist angle of the target wire based on the evaluation value calculated by the calculation unit.

[0012] With this configuration, by focusing on the fact that the electrical characteristics of the target wire change due to twisting, the twist angle can be detected based on the evaluation value indicating the electrical characteristics of the target wire, thereby enabling the twist angle of the target wire to be detected with higher accuracy.

[0013] (2) In the above (1), the detection unit may detect the number of twists of the target line based on the detection result of the twist angle.

[0014] With this configuration, for example, it is possible to estimate the degree of deterioration of the target wire based on the detection result of the number of twists.

[0015] (3) In the above (1) or (2), the signal output unit may output the measurement signal to the target wire that constitutes the twisted wire, and the detection unit may further detect the twist direction of the target wire.

[0016] With this configuration, it is possible to distinguish and detect the twist angles in different twist directions.

[0017] (4) In any of (1) to (3) above, the detection unit may detect the twisting angle using a learning model created by machine learning the relationship between the twisting angle and the evaluation value.

[0018] With this configuration, the twist angle of the target wire can be detected easily and accurately.

[0019] (5) In any of (1) to (4) above, the detection unit may create time series data of the twisting angle, and calculate the rotation speed of the target line in the twisting operation based on the time series data.

[0020] With this configuration, it is possible to detect the twist state of the target wire in more detail.

[0021] (6) In any of (1) to (5) above, the signal output unit may output the measurement signal to a plurality of target wires that constitute a twisted wire and have different twist directions, the measurement unit may receive a plurality of response signals corresponding to the plurality of target wires and measure at least one of the amplitude and phase of each of the received response signals, the calculation unit may calculate a plurality of evaluation values ​​corresponding to the plurality of target wires based on the measurement results by the measurement unit, and the detection unit may detect the twist angle based on the plurality of evaluation values ​​calculated by the calculation unit.

[0022] With this configuration, it is possible to detect the twist angle in a wider angle range with high sensitivity based on the evaluation values ​​corresponding to the plurality of target wires having different twist directions.

[0023] (7) A detection method according to an embodiment of the present disclosure is a detection method in a detection device, and includes the steps of outputting a measurement signal having a frequency component to a target wire, receiving a response signal based on the measurement signal and measuring at least one of the amplitude and phase of the received response signal, calculating an evaluation value based on the measurement results of at least one of the amplitude and the phase, and detecting the twist angle of the target wire based on the calculated evaluation value.

[0024] This method focuses on the fact that the electrical characteristics of the target wire change due to twisting, and can detect the twist angle based on the evaluation value indicating the electrical characteristics of the target wire, thereby making it possible to detect the twist angle of the target wire with higher accuracy.

[0025] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, identical or corresponding parts are designated by the same reference numerals, and their description will not be repeated. Furthermore, at least some of the embodiments described below may be combined in any manner.

[0026] First Embodiment [Configuration and Basic Operation] Fig. 1 is a diagram showing the configuration of a communication system according to a first embodiment of the present disclosure. Referring to Fig. 1, a communication system 301 includes communication devices 101 and 111. Note that the communication system 301 may include a plurality of communication devices 111.

[0027] The communication devices 101 and 111 are connected to each other via a communication transmission line 10. More specifically, the transmission line 10 includes a cable portion and connector portions provided at a first end and a second end of the cable portion, respectively. The connector portion provided at the first end of the cable portion is connected to the communication device 101. The connector portion provided at the second end of the cable portion is connected to the communication device 111. The transmission line 10 is, for example, an Ethernet (registered trademark) cable.

[0028] The communication system 301 is used, for example, in factory automation. More specifically, the communication devices 101 and 111 are mounted on the robot arm of an industrial robot. The communication device 101 transmits a communication signal to the communication device 111. The communication device 111 operates an actuator (not shown) or the like in accordance with the communication signal received from the communication device 101. The communication system 301 may also be used, for example, in a home network.

[0029] 2 is a diagram illustrating an example of a transmission line used in the communication system according to the first embodiment of the present disclosure, showing a cross-sectional view of the transmission line 10 when the transmission line 10 is cut along a plane perpendicular to the longitudinal direction of the transmission line 10.

[0030] 2, the transmission line 10 includes a plurality of core wires 1 and a sheath 2. The core wires 1 are covered with a covering layer (not shown) and are insulated from each other. The conductor portion of the core wire 1 may be a single core or may be a bundle of multiple thin wires. The multiple core wires 1 are bundled together by the sheath 2. The space between the core wires 1 and the sheath 2 may be filled with an insulator.

[0031] For example, the transmission line 10 includes a core wire 1 that forms a twisted wire. More specifically, the transmission line 10 includes core wires 1A and 1B that are twisted together to form a twisted pair wire. The core wire 1A is an example of a symmetric wire. For example, the core wires 1A and 1B are core wires 1 used to transmit communication signals between the communication unit 11 and the communication device 111. For example, the twist direction At1 of the core wires 1A and 1B is counterclockwise. In other words, the twist direction At1 of the core wires 1A and 1B is a left twist, i.e., a Z twist. Note that the twist direction At1 of the core wires 1A and 1B may also be a right twist, i.e., an S twist.

[0032] The core wires 1 other than the core wires 1A and 1B in the transmission line 10 may be core wires 1 twisted together with other core wires 1 to form a twisted pair wire, or may be untwisted parallel wires. When the core wires 1 other than the core wires 1A and 1B form a twisted pair wire, the core wires 1 that form the twisted pair wire may be twisted left-handed like the core wires 1A and 1B, or may be twisted right-handed.

[0033] In addition, the transmission line 10 may be configured to include a spiral restraining material instead of the sheath 2 as a member for bundling the multiple core wires 1, or may be configured to include multiple binding bands spaced apart along the length of the transmission line 10.

[0034] The transmission line 10 and the core wires 1 are twisted around an axis that is the longitudinal direction of the transmission line 10 in accordance with the operation of the robot arm on which the communication devices 101 and 111 are mounted. When the transmission line 10 is twisted in the direction opposite to the twisting direction At, the twisting of the core wires 1A and 1B in the twisted pair is loosened. On the other hand, when the transmission line 10 is twisted in the same direction as the twisting direction At1, the twisting of the core wires 1A and 1B in the twisted pair is tightened.

[0035] The communication device 101 functions as a detection device and performs a detection process to detect the twist angle θ of the core wire 1A, i.e., the twist angle θ of the transmission line 10. Hereinafter, the twist angle θ when the transmission line 10 is twisted in a clockwise twist direction is taken as a positive value. Also, the twist angle θ when the transmission line 10 is twisted in a counterclockwise twist direction is taken as a negative value.

[0036] [Problem] A technology capable of detecting the twist angle θ of the transmission line 10 with higher accuracy is desired. More specifically, fatigue deterioration of the transmission line 10 progresses depending on the twist angle θ and the number of twists, and the line may break. Furthermore, the transmission line 10 may be twisted at a twist angle θ that exceeds the twist resistance of the transmission line 10 or may be twisted for an unauthorized purpose. A technology capable of checking the state of the transmission line 10 is desired in order to accurately estimate the degree of progression of fatigue deterioration of the transmission line 10 and to take appropriate measures, such as issuing a warning to a user, when the transmission line 10 is not being used normally and safely.

[0037] However, the conventional technique described in Patent Document 1 cannot detect the twist angle θ.

[0038] Therefore, the communication device 101 according to the embodiment of the present disclosure solves the above problem by having the following configuration.

[0039] (Communication Device) FIG. 3 is a diagram illustrating the configuration of a communication device according to the first embodiment of the present disclosure. Referring to FIG. 3, the communication device 101 includes a communication unit 11, a detection processing unit 20, and a communication port 30. The detection processing unit 20 includes a signal output unit 12, a measurement unit 13, a processing unit 14, and a storage unit 15. The processing unit 14 is an example of a calculation unit and an example of a detection unit. Some or all of the communication unit 11, the signal output unit 12, the measurement unit 13, and the processing unit 14 are implemented, for example, by a processing circuit including one or more processors. The storage unit 15 is, for example, a non-volatile memory included in the processing circuit. The communication port 30 is, for example, a connector or a terminal. A connector portion of the transmission line 10 is connected to the communication port 30.

[0040] For example, the end of the transmission line 10 on the communication device 111 side is impedance-matched. More specifically, the end of the transmission line 10 on the communication device 111 side is connected to a termination circuit (not shown). The termination circuit is a 50 Ω resistor that is equal to the characteristic impedance of the transmission line 10, and is used to match the termination of the transmission line 10. Note that the termination circuit may be a load other than a 50 Ω resistor, and may not accurately match the termination of the transmission line 10. In other words, the end of the transmission line 10 does not need to be accurately impedance-matched.

[0041] (Communication Unit) The communication unit 11 periodically or irregularly generates a communication signal addressed to the communication device 111 and transmits the generated communication signal to the communication device 111 via the communication port 30 and the transmission line 10. The communication unit 11 also receives a communication signal from the communication device 111 via the transmission line 10 and the communication port 30.

[0042] (Signal Output Unit) The signal output unit 12 outputs a measurement signal having a frequency component to the core wire 1 A. For example, the signal output unit 12 outputs an AC signal, a pulse signal, or a frequency sweep signal as the measurement signal to the core wire 1 A.

[0043] The signal output unit 12 outputs a measurement signal having a frequency band different from the frequency band of the communication signal transmitted by the communication unit 11 via the transmission line 10 to the core wire 1A via the communication port 30. In other words, the communication device 101 frequency-division multiplexes the communication signal and the measurement signal.

[0044] More specifically, the signal output unit 12 outputs a measurement signal to the core wire 1A via the communication port 30 during a detection period T1 during which the power of the communication device 101 is turned on, for example.

[0045] For example, the storage unit 15 stores a digital signal D1 having N samples obtained by digitally converting one cycle of a sine wave, where N is an integer of 2 or greater.

[0046] During the detection period T1, the signal output unit 12 repeatedly uses N digital signals D1 corresponding to one cycle of a sine wave stored in the storage unit 15 to continuously output a measurement signal to the core wire 1A. More specifically, the signal output unit 12 includes a DA (Digital to Analog) conversion unit. The signal output unit 12 acquires the digital signal D1 from the storage unit 15 at an output timing that corresponds to a cycle C1 of the operating clock of the DA conversion unit, converts the digital signal D1 to an analog signal using the DA conversion unit, and outputs the generated measurement signal to the core wire 1A via the communication port 30. The signal output unit 12 also outputs the digital signal D1 acquired from the storage unit 15 at the output timing to the measurement unit 13 and the processing unit 14.

[0047] The signal output unit 12 may include a signal generating unit such as a DDS (Direct Digital Synthesizer) and output a signal generated by the signal generating unit to the core wire 1A via the communication port 30.

[0048] (Measurement Unit) The measurement unit 13 receives a response signal based on the measurement signal. For example, the measurement unit 13 receives a response signal including a signal obtained by reflecting the measurement signal from the core wire 1A. More specifically, the measurement unit 13 receives a response signal including the measurement signal output by the signal output unit 12 and a reflected signal obtained by reflecting the measurement signal from the core wire 1A via the communication port 30. The measurement unit 13 then measures the amplitude and phase of the received response signal.

[0049] More specifically, during the detection period T1, the measurement unit 13 receives a response signal from the core wire 1A via the communication port 30. For example, the measurement unit 13 performs preprocessing using a low-pass filter or the like to remove noise contained in the response signal.

[0050] The measurement unit 13 includes an AD (Analog to Digital) converter that samples the response signal at sampling timings according to the period C1. The measurement unit 13 generates a digital signal D2A that is time-series data made up of a plurality of sample values ​​by sampling the response signal that has been received from the core wire 1A and has undergone preprocessing using the AD converter.

[0051] For example, the measurement unit 13 generates a digital signal D3A that is time-series data indicating the reflected signal by subtracting the digital signal D1 received from the signal output unit 12 for each sample from the generated digital signal D2A. The measurement unit 13 generates amplitude data D3aA that is time-series data on the amplitude of the reflected signal and phase data D3pA that is time-series data on the phase of the reflected signal based on the generated digital signal D3A, and outputs the generated amplitude data D3aA and phase data D3pA to the processing unit 14.

[0052] (Processing Unit) The processing unit 14 calculates the evaluation value EvA based on the measurement result by the measuring unit 13. The processing unit 14 detects the twist angle θ of the core wire 1A based on the calculated evaluation value EvA.

[0053] For example, the processing unit 14 further detects the twist direction of the core wire 1A based on the evaluation value EvA. More specifically, the processing unit 14 detects whether the twist direction of the transmission line 10 is the same as the twist direction At1 or the opposite direction to the twist direction At1. That is, the processing unit 14 detects the negative twist angle θ and the positive twist angle θ.

[0054] (1) Calculation of Evaluation Value EvA For example, the processing unit 14 calculates, as the evaluation value EvA, a reflection coefficient rcA, which is the ratio of the amplitude of the measurement signal output to the core wire 1A to the amplitude of the reflected signal from the core wire 1A.

[0055] More specifically, the processing unit 14 generates amplitude data D1a, which is time-series data of the amplitude of the measurement signal, based on the digital signal D1 received from the signal output unit 12.

[0056] The processing unit 14 calculates a value VA by dividing the amplitude data D3aA received from the measurement unit 13 by the amplitude data D1a, for example, for each period of the measurement signal, i.e., for each N number of samples. More specifically, the processing unit 14 calculates a value VA by dividing the average value of the N number of sample values ​​of the amplitude data D3aA by the average value of the N number of sample values ​​of the amplitude data D1a. The processing unit 14 calculates a reflection coefficient rcA based on the calculated value VA.

[0057] 4 is a diagram illustrating an example of a reflection coefficient calculated by a processing unit in a communication device according to a first embodiment of the present disclosure. In FIG. 4, the horizontal axis represents time [seconds], and the vertical axis represents the reflection coefficient. FIG. 4 illustrates time-series data DrcA of the reflection coefficient rcA calculated by the processing unit 14 when a twisting test BT is performed in which a twisting operation in which the transmission line 10 is twisted at a constant twisting speed until the twisting angle θ becomes +180° and a twisting operation in which the transmission line 10 is twisted at a constant twisting speed until the twisting angle θ becomes −180° are alternately repeated.

[0058] 4, the processing unit 14 calculates the reflection coefficient rcA at a calculation timing according to a predetermined calculation period Cm. The calculation period Cm is set to a value shorter than the period of bending assumed in the transmission line 10, for example, a value corresponding to the period of the measurement signal.

[0059] (2) Detection of Twist Angle θ For example, the memory unit 15 stores a learning model Md1. The learning model Md1 is created in advance by machine learning the relationship between the twist angle θ and the reflection coefficient rcA using a machine learning method such as linear regression and deep learning. The learning model Md1 may be created by the processing unit 14 or by a device external to the communication device 101.

[0060] The processing unit 14 detects the twist angle θ using the learning model Md1 in the storage unit 15. More specifically, every time the processing unit 14 extracts a reflection coefficient rcA, the processing unit 14 provides the extracted reflection coefficient rcA to the learning model Md1 to obtain the twist angle θ.

[0061] Fig. 5 is a diagram showing an example of the detection result of the twist angle θ by the processing unit in the communication device according to the first embodiment of the present disclosure. In Fig. 5, the horizontal axis represents time [seconds], and the vertical axis represents the twist angle θ [degrees]. The solid line in Fig. 5 represents the time-series data Dt1 of the twist angle θ detected by the processing unit 14 when the above-mentioned twist test BT was performed. The dashed line in Fig. 5 represents the actual twist angle θ in the twist test BT.

[0062] 5 , the processing unit 14 generates time-series data Dt1 of the twist angle θ. More specifically, each time the processing unit 14 acquires the twist angle θ, the processing unit 14 updates the time-series data Dt1 by storing the acquired twist angle θ in the storage unit 15. The detection result of the twist angle θ by the processing unit 14 is highly correlated with the actual twist angle θ of the transmission line 10 and can distinguish between a twist angle θ in the same direction as the twist direction At1 of the core wire 1A and a twist angle θ in the opposite direction to the twist direction At1 of the core wire 1A. However, the detection result of the twist angle θ by the processing unit 14 is less correlated with the actual twist angle θ of the transmission line 10 when the twist angle θ is in an angle range of −50° or less.

[0063] For example, the processing unit 14 performs a process of displaying the calculation result of the reflection coefficient rcA and the detection result of the twisting angle θ. More specifically, the processing unit 14 performs a process of displaying the time-series data DrcA of the reflection coefficient rcA and the time-series data Dt1 of the twisting angle θ on a display device (not shown).

[0064] Furthermore, for example, the processing unit 14 calculates the rotation speed Bv of the twisting operation of the core wire 1A based on the time-series data Dt1. More specifically, the processing unit 14 calculates the rotation speed Bv by differentiating the time-series data Dt1.

[0065] Furthermore, for example, the processing unit 14 detects the number of twists of the core wire 1A based on the detection result of the twist angle θ. More specifically, when the twist angle θ transitions from a value equal to or less than the threshold value Th2 to a value equal to or greater than the threshold value Th1 and then transitions from a value equal to or greater than the threshold value Th1 to a value equal to or less than the threshold value Th2, the processing unit 14 determines that the twist angle θ of the transmission line 10 has made one round trip between the predetermined value Pv2 and the predetermined value Pv1, and counts up the count value Cv of the number of twists. Here, the threshold value Th1 is greater than the threshold value Th2. For example, the predetermined value Pv2 is a negative value, and the predetermined value Pv1 is a positive value. For example, when the count value Cv exceeds a predetermined value, the processing unit 14 performs a notification process, for example, to notify the user of a predetermined warning.

[0066] Furthermore, for example, when the twist angle θ becomes larger than a predetermined upper limit value θmax or smaller than a predetermined lower limit value θmin, the processing unit 14 performs a notification process to notify the user of a predetermined warning. The upper limit value θmax and the lower limit value θmin may be values ​​preset by the user or may be values ​​determined by machine learning the detection result of the twist angle θ.

[0067] [Operation Flow] FIG. 6 is a flowchart defining an example of an operation procedure when a communication device according to an embodiment of the present disclosure performs a detection process.

[0068] 6, first, when communication device 101 is powered on, for example, communication device 101 starts outputting a measurement signal to core wire 1A and receiving a response signal from core wire 1A (step S11).

[0069] Next, the communication device 101 waits for the timing to calculate the reflection coefficient rcA (NO in step S12), and when the calculation timing arrives (YES in step S12), it calculates the reflection coefficient rcA based on the amplitude data D1a, which is time-series data of the amplitude of the measurement signal, and the amplitude data D3aA (step S13).

[0070] Next, the communication device 101 obtains the twist angle θ by providing the reflection coefficient rcA to the learning model Md1, and stores the obtained twist angle θ in the storage unit 15 (step S14).

[0071] Next, when the twist angle θ transitions from a value greater than or equal to the threshold value Th1 to a value less than or equal to the threshold value Th2 (YES in step S15), the communication device 101 counts up the count value Cv of the number of twists (step S16) and waits for a new timing to calculate the reflection coefficient rcA (NO in step S12).

[0072] On the other hand, if the twisting angle θ does not transition from a value greater than or equal to the threshold value Th1 to a value less than or equal to the threshold value Th2 (NO in step S15), the communication device 101 waits for a new timing to calculate the reflection coefficient rcA without counting up the count value Cv (NO in step S12).

[0073] In the communication device 101 according to the first embodiment of the present disclosure, the signal output unit 12 is configured to output to the core wire 1A a measurement signal in a frequency band different from the frequency band of the communication signal transmitted by the communication unit 11 via the transmission line 10 during the detection period T1, which is a period during which the communication device 101 is powered on. However, this is not limited to this. The signal output unit 12 may be configured to output to the core wire 1A a measurement signal in a frequency band that includes part or all of the frequency band of the communication signal during a period during which the communication device 101 is powered on and the communication unit 11 does not transmit the communication signal.

[0074] Furthermore, in the communication device 101 according to the first embodiment of the present disclosure, the signal output unit 12 is configured to output a measurement signal to the core wire 1A, but this is not limited to this. The signal output unit 12 may be configured to output a measurement signal to the core wire 1B instead of the core wire 1A. In this case, the measurement unit 13 receives a response signal from the core wire 1B and measures the amplitude and phase of the received response signal. The processing unit 14 calculates an evaluation value based on the measurement result by the measurement unit 13 and detects the twist angle θ of the core wire 1B based on the calculated evaluation value.

[0075] Furthermore, in the communication device 101 according to the first embodiment of the present disclosure, the measurement unit 13 is configured to receive from the core wire 1A a response signal that includes a measurement signal output by the signal output unit 12 and a reflected signal that is a signal obtained by reflecting the measurement signal. However, this is not limited to this. The measurement unit 13 may also be configured to receive a response signal that does not include a measurement signal. In other words, the measurement unit 13 may be configured to receive a reflected signal as a response signal. More specifically, for example, the signal output unit 12 outputs a measurement signal to the core wire 1A via a directional coupler and a communication port 30. The measurement unit 13 receives a response signal that does not include a measurement signal from the core wire 1A via the communication port 30 and the directional coupler.

[0076] Furthermore, in the communication device 101 according to the first embodiment of the present disclosure, the measuring unit 13 is configured to generate the digital signal D3A indicating the reflected signal by subtracting the digital signal D1 from the digital signal D2A, but this is not limited to this. The measuring unit 13 may also be configured to receive a measurement signal from the signal output unit 12, subtract the measurement signal from the received response signal to generate an analog signal indicating the reflected signal, and digitally convert the generated analog signal to generate the digital signal D3A.

[0077] Furthermore, in the communication device 101 according to the first embodiment of the present disclosure, the measurement unit 13 is configured to receive a response signal, including a signal resulting from the reflection of the measurement signal, from the core wire 1A used to transmit the communication signal. However, this is not limited to this. The core wires 1A and 1B may be core wires 1 for detection processing that are not used to transmit communication signals in the communication devices 101 and 111, and the end on the communication device 111 side may be terminated. In this case, the measurement unit 13 may receive a return signal of the measurement signal from the core wire 1B as the response signal. Furthermore, when the core wires 1A and 1B are core wires 1 for detection processing, they only need to be twisted in the twisted section, which is the section where they can be twisted, and they do not need to be twisted in sections other than the twisted section. Furthermore, when the core wires 1A and 1B are core wires 1 for detection processing, the twist pitch of the core wires 1A and 1B may be the same as or different from the twist pitch of the core wires 1 constituting the twisted pair wire used to transmit communication signals.

[0078] Furthermore, although the communication device 101 according to the first embodiment of the present disclosure is configured to detect the twist angle θ of the core wire 1A constituting the twisted pair line, this is not limiting. The communication device 101 may also be configured to detect the twist angle θ of the core wires 1, which are parallel lines. More specifically, the transmission line 10 includes the core wires 1, which are parallel lines and are arranged at a position off-center in a cross section perpendicular to the longitudinal direction of the transmission line 10. The signal output unit 12 outputs a measurement signal to the core wire 1. The measurement unit 13 receives a response signal from the core wire 1 and measures the amplitude and phase of the received response signal. The processing unit 14 calculates an evaluation value based on the measurement result by the measurement unit 13 and detects the twist angle θ of the core wire 1 based on the calculated evaluation value. In this case, the twist angle θ detected by the processing unit 14 is, for example, a value equal to or greater than zero degrees. The processing unit 14 detects the twist angle θ but does not detect the twist direction. For example, if the twist angle θ transitions from zero degrees to a value equal to or greater than the threshold value Th1, and then transitions from a value equal to or greater than the threshold value Th1 back to zero degrees, the processing unit 14 determines that the twist angle θ of the transmission line 10 has made one round trip between zero degrees and a predetermined value Pv1, and counts up the count value Cv of the number of twists.

[0079] Furthermore, although the communication device 101 according to the first embodiment of the present disclosure is configured to detect the twist angle θ of the core wire 1A constituting a twisted pair wire, this is not limiting. The communication device 101 may also be configured to detect the twist angle θ of the core wire 1 in a twisted wire composed of three or more core wires 1. More specifically, the transmission line 10 includes, for example, three core wires 1 twisted together to form the twisted wire. The signal output unit 12 outputs a measurement signal to one of the three core wires 1. The measurement unit 13 receives a response signal from the core wire 1 and measures the amplitude and phase of the received response signal. The processing unit 14 calculates an evaluation value based on the measurement result by the measurement unit 13 and detects the twist angle θ of the core wire 1 based on the calculated evaluation value.

[0080] Furthermore, in the communication device 101 according to the first embodiment of the present disclosure, when the twist angle θ transitions from a value equal to or less than the threshold value Th2 to a value equal to or greater than the threshold value Th1 and then transitions from a value equal to or greater than the threshold value Th1 back to a value equal to or less than the threshold value Th2, the processing unit 14 determines that the twist angle θ of the transmission line 10 has made one round trip between the predetermined value Pv2 and the predetermined value Pv1, and increments the count value Cv of the number of twists. However, this is not limited to this. The processing unit 14 may be configured to increment the count value Cv using a value obtained by differentiating a moving average of the twist angle θ instead of the twist angle θ.

[0081] In addition, in the communication device 101 according to the first embodiment of the present disclosure, the processing unit 14 is configured to detect the number of twists of the core wire 1A, but this is not limitative. The processing unit 14 may be configured not to detect the number of twists of the core wire 1A.

[0082] Furthermore, in the communication device 101 according to the first embodiment of the present disclosure, the processing unit 14 is configured to detect the twist angle θ using the learning model Md1, but this is not limited to this. The processing unit 14 may be configured not to use the learning model Md1. In this case, for example, the processing unit 14 detects the twist angle θ using the calculated reflection coefficient rcA and a table showing the correspondence relationship between the reflection coefficient rcA and the twist angle θ.

[0083] Furthermore, in the communication device 101 according to the first embodiment of the present disclosure, the processing unit 14 is configured to calculate the rotation speed Bv, but this is not limiting. The processing unit 14 may be configured not to calculate the rotation speed Bv.

[0084] Furthermore, in the communication device 101 according to the first embodiment of the present disclosure, the processing unit 14 is configured to calculate the reflection coefficient rcA as the evaluation value EvA, but this is not limited to this. The processing unit 14 may be configured to calculate, instead of the reflection coefficient rcA, the impedance ZA of the core wire 1A, the reactance XA of the core wire 1A, or the resistance RA of the core wire 1A as the evaluation value EvA, or the phase difference pdA between the measurement signal and the reflected signal in the core wire 1A.

[0085] Furthermore, when the end of the transmission line 10 on the communication device 111 side is open, the processing unit 14 may be configured to calculate the capacitance CA of the core wire 1A as the evaluation value EvA.

[0086] Furthermore, when the end of the transmission line 10 on the communication device 111 side is connected to a ground node, the processing unit 14 may be configured to calculate the inductance LA of the core wire 1A as the evaluation value EvA.

[0087] The communication system 301 according to the first embodiment of the present disclosure may include a switching device that switches the state of the end of the transmission line 10 on the communication device 111 side between a first state in which the end is open, a second state in which the end is connected to a ground node, and a third state in which the end is connected to a termination circuit. In this case, the processing unit 14 calculates multiple types of evaluation values ​​EvA by transmitting a control signal to the switching device and switching the state of the end of the transmission line 10 on the communication device 111 side.

[0088] Next, other embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals and their description will not be repeated.

[0089] Second Embodiment This embodiment relates to a communication device 102 that outputs measurement signals to a plurality of core wires 1, as compared with the communication device 101 according to the first embodiment. Other than the contents described below, the communication device 102 is the same as the communication device 101 according to the first embodiment.

[0090] 7 is a diagram illustrating a configuration of a communication system according to a second embodiment of the present disclosure. Compared to the communication system 301 illustrated in FIG. 1, the communication system 302 includes a communication device 102 instead of the communication device 101. The communication devices 102 and 111 are connected to each other via a communication transmission line 40. The transmission line 40 is, for example, an Ethernet cable.

[0091] 8 is a diagram illustrating an example of a transmission line used in a communication system according to a second embodiment of the present disclosure, showing a cross-sectional view of the transmission line 40 taken along a plane perpendicular to the longitudinal direction of the transmission line 40.

[0092] 8, compared to the transmission line 10, the transmission line 40 includes, in addition to the core wires 1A and 1B, core wires 1C and 1D that are twisted together to form a twisted pair wire. The core wire 1C is an example of a symmetric wire. The core wires 1A and 1B and the core wires 1C and 1D form different twisted pairs. The twist direction At1 of the core wires 1A and 1B and the twist direction At2 of the core wires 1C and 1D are different from each other. More specifically, the twist direction At2 of the core wires 1C and 1D is clockwise. In other words, the twist direction At2 of the core wires 1C and 1D is a right twist, i.e., an S twist.

[0093] The core wires 1 other than the core wires 1A, 1B, 1C, and 1D in the transmission line 40 may be core wires 1 twisted together with other core wires 1 to form a twisted pair wire, or may be untwisted parallel wires. When the core wires 1 other than the core wires 1A, 1B, 1C, and 1D form a twisted pair wire, the core wires 1 forming the twisted pair wire may be twisted left-handed like the core wires 1A and 1B, or twisted right-handed like the core wires 1C and 1D.

[0094] 9 is a diagram illustrating a configuration of a communication device according to a second embodiment of the present disclosure. Referring to FIG. 9, compared to communication device 101, communication device 102 includes a signal output unit 22 instead of signal output unit 12, a measurement unit 23 instead of measurement unit 13, a processing unit 24 instead of processing unit 14, and a storage unit 25 instead of storage unit 15. Processing unit 24 is an example of a calculation unit and an example of a detection unit.

[0095] The signal output unit 22 outputs a measurement signal having a frequency component to the core wires 1 having different twist directions. More specifically, the signal output unit 22 outputs the measurement signal to the core wires 1A and 1C via the communication port 30 during the detection period T1.

[0096] The measuring unit 23 receives two response signals corresponding to the core wires 1A and 1C, respectively. For example, the measuring unit 23 receives response signals including signals resulting from reflection of the measurement signal from the core wires 1A and 1C, respectively, and measures the amplitude and phase of each of the received response signals.

[0097] More specifically, during the detection period T1, the measurement unit 23 receives response signals from the core wires 1A and 1C via the communication port 30. Similar to the measurement unit 13, the measurement unit 23 generates amplitude data D3aA and phase data D3pA and outputs the generated amplitude data D3aA and phase data D3pA to the processing unit 24.

[0098] The measurement unit 23 also generates a digital signal D2B, which is time-series data consisting of a plurality of sample values, by using an AD conversion unit to sample the response signal received from the core wire 1C and subjected to preprocessing. The measurement unit 23 generates a digital signal D3B, which is time-series data indicating the reflected signal, by subtracting the digital signal D1 for each sample from the generated digital signal D2B. The measurement unit 23 generates amplitude data D3aB, which is time-series data on the amplitude of the reflected signal, and phase data D3pB, which is time-series data on the phase of the reflected signal, based on the generated digital signal D3B, and outputs the generated amplitude data D3aB and phase data D3pB to the processing unit 24.

[0099] The processing unit 24 calculates evaluation values ​​EvA and EvB corresponding to the core wires 1A and 1C, respectively, based on the measurement results by the measurement unit 23. The processing unit 24 detects the twist angle θ based on the calculated evaluation values ​​EvA and EvB.

[0100] The processing unit 24 calculates the reflection coefficient rcA in the same manner as the processing unit 14. Furthermore, the processing unit 24 calculates, as the evaluation value EvB, the reflection coefficient rcB, which is the ratio of the amplitude of the measurement signal output to the core wire 1C to the amplitude of the reflected signal at the core wire 1C.

[0101] More specifically, the processing unit 24 calculates a value VB by dividing the amplitude data D3aB received from the measurement unit 23 by the amplitude data D1a, for example, for each period of the measurement signal, i.e., for each N samples. Specifically, the processing unit 24 calculates a value VB by dividing the average value of the N sample values ​​of the amplitude data D3aB by the average value of the N sample values ​​of the amplitude data D1a. The processing unit 24 calculates a reflection coefficient rcB based on the calculated value VB. The processing unit 24 then calculates a difference DrcAB by subtracting the reflection coefficient rcB from the reflection coefficient rcA.

[0102] 10 is a diagram illustrating an example of reflection coefficients calculated by a processing unit in a communication device according to a second embodiment of the present disclosure. In FIG. 10, the horizontal axis represents time [seconds], and the vertical axis represents reflection coefficients. FIG. 10 illustrates time-series data DrcA and DrcB of the reflection coefficients rcA and rcB calculated by the processing unit 24 when the above-described twisting test BT is performed.

[0103] 10, the reflection coefficient rcA reaches its maximum value at times t1, t3, and t5 when the twist angle θ reaches +180° in the twisting test BT. On the other hand, the reflection coefficient rcB reaches its maximum value at times t2 and t4 when the twist angle θ reaches −180° in the twisting test BT. This is because the twist directions At1 and At2 of the core wires 1A and 1C are different from each other.

[0104] For example, the memory unit 25 stores a learning model Md2. The learning model Md2 is created in advance by machine learning the relationship between the twisting angle θ and the difference DrcAB using machine learning techniques such as linear regression and deep learning. The learning model Md2 may be created by the processing unit 24 or by a device external to the communication device 102.

[0105] Each time the processing unit 24 calculates the difference DrcAB, it provides the calculated difference DrcAB to the learning model Md2 to obtain the twisting angle θ.

[0106] 11 is a diagram illustrating an example of a detection result of the twist angle θ by the processing unit in the communication device according to the second embodiment of the present disclosure. In FIG. 11, the horizontal axis represents time [seconds], and the vertical axis represents the twist angle θ [degrees]. The solid line in FIG. 11 represents time-series data Dt2 of the twist angle θ detected by the processing unit 24 when the above-described twist test BT was performed.

[0107] 11 , the processing unit 24 generates time-series data Dt2 of the twist angle θ. More specifically, every time the processing unit 24 acquires the twist angle θ, the processing unit 24 updates the time-series data Dt2 by storing the acquired twist angle θ in the storage unit 25. The detection result of the twist angle θ by the processing unit 24 has a high correlation with the actual twist angle θ of the transmission line 10 in an angle range from +180° to −180°. Therefore, the processing unit 24 can detect the twist angle θ with high sensitivity in a wide angle range, including an angle range in which the twist angle θ is −50° or less.

[0108] In the communication device 102 according to the second embodiment of the present disclosure, the storage unit 25 is configured to store the learning model Md2, but this is not limiting. Instead of the learning model Md2, the storage unit 25 may store a learning model Md3 created by machine learning the relationship between the twist angle θ and the reflection coefficients rcA and rcB. In this case, the processing unit 24 acquires the twist angle θ by providing the reflection coefficients rcA and rcB to the learning model Md3.

[0109] Furthermore, in the communication device 102 according to the second embodiment of the present disclosure, the measurement unit 23 is configured to receive response signals, including signals resulting from reflection of the measurement signal, from the core wires 1A and 1C used to transmit the communication signals, respectively. However, this is not limited to this. The core wires 1C and 1D may be core wires 1 for detection processing that are not used to transmit communication signals in the communication devices 101 and 111, and their ends on the communication device 111 side may be terminated. In this case, the measurement unit 23 may be configured to receive a return signal of the measurement signal as the response signal from the core wire 1D. Furthermore, when the core wires 1C and 1D are core wires 1 for detection processing, they only need to be twisted together in the twisted sections, and they do not need to be twisted together in sections other than the twisted sections. Furthermore, when the core wires 1C and 1D are core wires 1 for detection processing, the twist pitch of the core wires 1C and 1D may be the same as or different from the twist pitch of the core wires 1 constituting the twisted pair wire used to transmit the communication signals.

[0110] The above-described embodiments should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims.

[0111] Each process (each function) in the above-described embodiments is realized by a processing circuit (circuitry) including one or more processors. The processing circuit may be configured as an integrated circuit or the like that combines one or more memories, various analog circuits, and various digital circuits in addition to the one or more processors. The one or more memories store programs (instructions) that cause the one or more processors to execute each of the processes. The one or more processors may execute each of the processes according to the program read from the one or more memories, or may execute each of the processes according to a logic circuit designed in advance to execute each of the processes. The processor may be any of various processors suitable for computer control, such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), and an ASIC (Application Specific Integrated Circuit). Note that the physically separated processors may cooperate with each other to execute the processes. For example, the processors installed in the physically separated computers may cooperate with each other via a network such as a LAN (Local Area Network), a WAN (Wide Area Network), or the Internet to execute the processes. The program may be installed into the memory from an external server device or the like via the network, or may be distributed in a state stored on a recording medium such as a CD-ROM (Compact Disc Read Only Memory), a DVD-ROM (Digital Versatile Disc Read Only Memory), or a semiconductor memory, and then installed into the memory from the recording medium.

[0112] The above description includes the following additional features: [Supplementary Note 1] A detection device comprising a processing circuit, wherein the processing circuit outputs a measurement signal having a frequency component to a target wire, receives a response signal from the target wire including a signal resulting from reflection of the measurement signal, measures at least one of an amplitude and a phase of the received response signal, calculates an evaluation value based on a measurement result of at least one of the amplitude and the phase, and detects a twist angle of the target wire based on the calculated evaluation value.

[0113] REFERENCE SIGNS LIST 1 Core wire 1A, 1C Core wire (target wire) 1B, 1D Core wire 2 Sheath 10, 40 Transmission line 11 Communication unit 12, 22 Signal output unit 13, 23 Measurement unit 14, 24 Processing unit (calculation unit, detection unit) 15, 25 Storage unit 20 Detection processing unit 30 Communication port 101, 102 Communication device (detection device) 111 Communication device 301, 302 Communication system DrcA, DrcB, Dt1, Dt2 Time series data

Claims

1. A detection device comprising: a signal output unit that outputs a measurement signal having frequency components to a target wire; a measurement unit that receives a response signal based on the measurement signal and measures at least one of the amplitude and phase of the received response signal; a calculation unit that calculates an evaluation value based on the measurement result by the measurement unit; and a detection unit that detects the twist angle of the target wire based on the evaluation value calculated by the calculation unit.

2. The detection device according to claim 1, wherein the detection unit detects the number of twists of the target wire based on the detection result of the twist angle.

3. A detection device as described in claim 1 or claim 2, wherein the signal output unit outputs the measurement signal to the target wire that constitutes a twisted wire, and the detection unit further detects the twist direction of the target wire.

4. A detection device according to any one of claims 1 to 3, wherein the detection unit detects the twisting angle using a learning model created by machine learning the relationship between the twisting angle and the evaluation value.

5. A detection device according to any one of claims 1 to 4, wherein the detection unit creates time series data of the twisting angle and calculates the rotation speed of the target wire during the twisting operation based on the time series data.

6. A detection device as described in any one of claims 1 to 5, wherein the signal output unit outputs the measurement signal to a plurality of target wires that constitute a twisted wire and have different twist directions; the measurement unit receives a plurality of response signals corresponding to the plurality of target wires and measures at least one of the amplitude and phase of each of the received response signals; the calculation unit calculates a plurality of evaluation values ​​corresponding to the plurality of target wires based on the measurement results by the measurement unit; and the detection unit detects the twist angle based on the plurality of evaluation values ​​calculated by the calculation unit.

7. A detection method for a detection device, comprising: a step of outputting a measurement signal having frequency components to a target wire; a step of receiving a response signal based on the measurement signal and measuring at least one of the amplitude and phase of the received response signal; a step of calculating an evaluation value based on the measurement results of at least one of the amplitude and the phase; and a step of detecting the twist angle of the target wire based on the calculated evaluation value.

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