JP2019109073A - Detection system and detection method - Google Patents

Abstract

To provide a detection system which detects contact and breakage which occur on a surface of a physical object.SOLUTION: In a detection system which detects a physical change of a physical object, comprising a structure 1 which is molded in a shape that corresponds to a surface shape of the physical object, and is adhered on a surface of the physical object, and a terminal 2 set up at an arbitrary position of the structure 1, the terminal 2 comprises a signal sending and receiving section 21 which sends signals to the inside of the structure 1, and receives the signals returned as transmitting the inside of the structure 1, a learning section 22 which stores data of received signals when the physical change does not occur in the structure 1, a judgement section 23 which judges presence of the physical change that occurs in the structure 1 on the basis of a comparison result between data of the signals and data of signals received at a predetermined time, and a notification section 24 which outputs abnormal information when the physical change occurs in the structure 1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a technology for detecting that a fracture such as cracking or peeling has occurred on the surface of any object, and that another object has come into contact.

  The sensor is composed of a transducer that converts physical stimulation into an electrical signal, and a detection circuit that receives the electrical signal generated by the transducer and detects the fact that the physical stimulation has occurred and its extent. . A wide variety of sensors such as temperature, humidity, light intensity, and gas concentration have already been put to practical use, and in terms of environmental measurement and convenience improvement as well as secondary industries such as mining industry, manufacturing industry and construction industry, It has become an indispensable technology for the next industry and the third industry. In the use of the sensor, it is necessary to place the detection circuit in advance where the physical change is to be detected and to operate the detection circuit to monitor the change of the transducer constantly or intermittently.

  One of the physical changes that is required to be detected in the industry is contact and destruction. These are useful for intrusion detection in security and deterioration detection in maintenance and management of equipment, and their importance is increasing with the improvement of safety awareness and the deterioration of equipment installed at the time of high economic growth. In order to carry out intrusion detection and deterioration detection with a sensor, it is necessary to solve the problem in which it is unclear in advance where the contact or destruction occurs. It is possible to narrow down the area that requires detection, such as a path that is important in the case of intrusion detection, and an important surface in maintenance of structural resistance in the case of deterioration detection of equipment, but in that area It is difficult to identify in advance up to the place of contact such as contact, cracking or peeling. However, usually, the sensor is set at a point where physical change occurs, and physical changes at other points can not be measured.

  In order to solve the said subject, the method of installing a sensor so that it may be equally distributed on the surface where contact or destruction generate | occur | produces, for example is considered. However, there is a problem that the required number of sensors increases because it is necessary to install the sensors at an interval sufficiently smaller than the area where contact or breakage occurs in order to prevent detection or failure of contact or breakage. For example, when it is assumed that a crack such as 10 cm or more or breakage such as peeling is detected on a surface of 100 cm square, the sensors need to be installed at intervals of 10 cm, and the required number is close to 100. It becomes very expensive.

  In order to easily realize planar detection, there is a method in which a sheet in which transducers are arranged at predetermined intervals and an electric circuit is mounted in advance is manufactured and attached to a place to be detected and installed (non-patent document) 1). Since this method facilitates the installation of sensors in field work, if the cost of sheet production can be reduced, it is advantageous in terms of human operation and production costs. However, this method makes it difficult to cut and connect in an arbitrary shape after sheet preparation because the transducers and electric circuits are built into the sheet. Therefore, the shape is not standardized and it is not suitable for objects having various surface shapes.

Yamashita, 2 others, "Development of sensor sheet for road infrastructure condition monitoring", Proceedings of 2015 Annual Conference of the Precision Engineering Society Spring Conference, Session ID: E69, p. 329-p. 330

  The present invention solves the problem when detecting contact or destruction on a predetermined object surface. First, it is a problem that it is necessary to detect a change that is not known how it occurs in a predetermined area. This change is contact, and breakage such as cracking or peeling, and it is assumed that the occurrence location and the generated size are unknown. The second problem is that the area to be detected has various shapes depending on the use conditions, and it is a problem that these shapes have to be flexibly coped with.

  Therefore, the object of the present invention made in view of such a point is to use a transducer whose shape can be changed by the user at the time of installation, and generate at any position on a predetermined object surface in any size. It is possible to detect contact and breakage such as cracking and peeling.

  In order to solve the above problems, in a detection system according to claim 1, in a detection system for detecting a physical change of an object, the detection system is molded into a shape according to the surface shape of the object and bonded to the surface of the object And a terminal installed at an arbitrary position of the structure, wherein the terminal transmits a signal to the inside of the structure, and propagates and returns the signal inside the structure. Based on the result of comparison between the signal transmitting / receiving unit to be received, the learning unit for storing the data of the signal received when there is no physical change in the structure, and the data of the signal and the data of the signal received at a predetermined time It is characterized by comprising: a determination unit that determines the presence or absence of a physical change that has occurred in the structure; and a notification unit that outputs abnormality information when there is a physical change in the structure.

  The detection system according to claim 2 is the detection system according to claim 1, wherein the physical change is a destruction that has occurred on the surface of the object or a contact of another object with the object. It is characterized by

  A detection system according to claim 3 is the detection system according to claim 1 or 2, wherein the signal is an electromagnetic wave or a sound wave, and includes a plurality of frequency components.

  The detection system according to claim 4 is the detection system according to any one of claims 1 to 3, wherein the size of the quarter wavelength of the wavelength of the signal is greater than the size of the physical change of the structure. It is also characterized by being small.

  A detection system according to claim 5 is the detection system according to any one of claims 1 to 4, characterized in that the structure is a dielectric sheet or is made of a paint.

  The detection system according to claim 6 is the detection system according to claim 1, wherein the signal is an electromagnetic wave, and the structure is a multilayer structure in which a dielectric is sandwiched between two conductive layers containing metal or metal powder. The electromagnetic wave is propagated in a parallel plate mode by the dielectric.

  The detection system according to claim 7 is the detection system according to any one of claims 1 to 6, wherein a plurality of the terminals are provided, and the plurality of terminals are located at different positions in an arbitrary position of the structure. The notification unit may further output temporal change data of a signal from the transmission to the reception of the structure.

  A detection method according to claim 8 comprises a structure molded into a shape according to the surface shape of an object, and bonded to the surface of the object, and a terminal installed at an arbitrary position of the structure. In the detection method for detecting a physical change of an object performed by a detection system, the terminal transmits a signal inside the structure, and propagates the inside of the structure and receives a signal returned. The steps of storing data of the received signal when there is no physical change in the structure, and physical properties generated in the structure based on a comparison result of the data of the signal and the data of the signal received at a predetermined time It is characterized by performing the step of determining the presence or absence of a temporary change, and the step of outputting the abnormality information when there is a physical change in the structure.

  According to the present invention, it is possible to detect contact generated on the surface of an object and breakage such as cracking or peeling.

It is a figure showing composition of a detection system concerning a 1st embodiment. It is a figure which shows the structure of the detection system which concerns on 2nd Embodiment. It is a figure showing composition of a structure. It is a figure which shows the example of a connection of a structure and the signal transmission / reception part of a terminal. It is a figure which shows the example of a connection of a structure and the signal transmission / reception part of a terminal. It is a figure which shows the example of a connection of a structure and the signal transmission / reception part of a terminal. It is a figure which shows the example of a connection of a structure and the signal transmission / reception part of a terminal.

  In order to solve the above-mentioned subject, a transducer concerning the present invention is a plane, and it is the characteristics that the shape can be set up arbitrarily. As a result, it becomes possible to use the detection target without exhausting the desired installation surface. In addition, by propagating waves such as electromagnetic waves or sound waves in the transducer and detecting changes in it, contacts, cracks, etc. that occur in any size on any part of the planar transducer can be generated. The feature is that it is possible to detect destruction such as peeling. Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

First Embodiment
First, the functional configuration of a detection system according to an embodiment of the present invention will be described using FIG. 1. FIG. 1 is a diagram showing the configuration of a detection system according to the first embodiment. This detection system is a detection system that detects a physical change that has occurred in an object, and includes a structure (transducer) 1 molded into a shape corresponding to the surface shape of the installation location, and a structure 1 above the structure 1 And a terminal (detection circuit) 2 installed at an arbitrary place or position. The terminal 2 includes a signal transmission / reception unit 21, a learning unit 22, a determination unit 23, and a notification unit 24. Hereinafter, details and operations of each component of the detection system will be described.

  The structure 1 is formed in advance by the installer according to the surface shape of the installation site, and has a plate-like shape having a predetermined thickness. For example, in the case of installation on a wall surface having a flat surface, it has a flat plate-like structure. When the installation surface is rounded, the structure 1 also has a rounded plate shape. In addition, even when there is any unevenness in the installation location, it has a shape that can be in close contact with the uneven surface.

  Also, the structure 1 is installed with sufficient adhesive strength to the installation target. Sufficient adhesive strength is a condition that it is sufficiently strong against external bending stress, tensile stress, compressive stress, etc., than the strength at which a crack or a hole occurs in the structure 1. That is, when a crack or peeling occurs in the installed object, the structure 1 does not lose adhesion between the structure 1 and the installation object, but the structure according to the crack or peeling of the installed object Cracks and tears occur in 1 as well.

  Moreover, the structure 1 is a structure which can propagate either an electromagnetic wave or a sound wave inside. For example, it is a dielectric or elastic body having a small dielectric loss characteristic. However, the dielectric constant and the shape are arbitrary.

  For example, a dielectric sheet can be used as the structure 1 having all the features described above. When a metal is used to form the structure 1, electromagnetic waves may be shielded depending on the structure. However, if a metal is used, electromagnetic waves can be efficiently propagated inside the structure 1 depending on the structure. Therefore, metals may be used as appropriate. For example, in the case where a metal is used for the surface layer portion and the adhesion surface of the structure 1 and the inside is a dielectric, the electromagnetic wave can be propagated in the parallel plate mode in the inside dielectric portion. This will be described in the third embodiment.

  The terminal 2 is installed at an arbitrary place of the structure 1, and has a function of transmitting a predetermined electromagnetic wave or sound wave from the signal transmitting / receiving unit 21 to the inside of the structure 1, receiving the signal returned through the structure 1 Equipped with

  Here, scattering of electromagnetic waves or sound waves generated inside the structure 1 will be described. Scattering generally means that when the wave travels in a uniform medium in one direction in one direction, the traveling direction becomes indeterminate if it encounters a medium disorder or another substance whose scale is shorter than the wavelength of the wave. It is a phenomenon.

  When the structure 1 has a scratch or a contact surface of another object, scattering (reflection) occurs in the electromagnetic wave or the sound wave. The degree of scattering is represented by a / λ from Maxwell's equation, where the wavelength of the wave is λ and the size of the flaw or the contact surface is a, and the larger the value, the larger the degree of scattering. When the size a of the flaw or the contact surface relative to the wavelength λ increases (a / λ = 1), the forward scattering rapidly increases compared to the backscattering, and the scattering (reflection) returns to the terminal 2 Less influence of

  Here, it is desirable that the size of the quarter wavelength of the wavelength of the electromagnetic wave or the sound wave is smaller than the length of the crack to be detected, the size of peeling, or the size of the contact surface when the object comes in contact. In this case, the scattering signal returning to the terminal 2 is efficiently received, and the detection sensitivity to the crack is improved. Such adjustment of the wavelength size can be realized by appropriately changing or setting the circuit configuration of the signal transmission / reception unit 21. In this embodiment, the operation will be described using an electromagnetic wave of a predetermined frequency as a transmission signal as an example.

  Then, each component which comprises the terminal 2 is demonstrated. Each component of the terminal 2 may be formed of hardware such as a circuit, for example, or may be formed of a software program.

The signal transmission / reception unit 21 generates an electromagnetic wave having one or more types of predetermined frequency components with a predetermined intensity, and transmits the electromagnetic wave toward the inside of the structure 1 as a transmission signal. Here, the transmission signal electromagnetic waves of consecutive waves of two frequencies of the different frequencies f ₁ and frequency f ₂ from each other. The transmission signal propagates in the structure 1 so as to spread around the terminal 2. In the structural body 1, loss due to propagation, spatial radiation at the end face, etc. occur and reflection occurs, but the signal group reflected at the end face etc. returns to the terminal 2. The signal transmission / reception unit 21 receives, as a reception signal, a superimposed signal group that has been fed back.

  The terminal 2 performs transmission and reception of the above-mentioned signal in two phases of a learning phase and a detection phase. The methods of processing the signals in each other's phases are different.

  First, the learning phase will be described. The learning phase is an operation performed by the terminal 2 immediately after the structure 1 and the terminal 2 are installed, that is, when there is no physical change in the structure 1, and the state immediately after the installation of the structure 1 is defined as a healthy state. Operation of storing the propagation state of the electromagnetic wave propagating through the structure 1 in the learning unit 22 as sound data.

In the learning phase, the signal transmitting / receiving unit 21 outputs the propagation characteristic data of the received signal to the learning unit 22 as sound data. The propagation characteristic data may be, for example, data of the phase or amplitude of the reception signal at the time of reception, or data of a reflection coefficient obtained by comparing the phase or amplitude of the transmission signal at each frequency. In the present embodiment, illustrating a case of recording the S ₁₁ of S parameters that are often used in a network analyzer or the like as the propagation characteristic data. S ₁₁ is a complex number obtained when the transmission signal expressed as a complex is taken as a denominator and the reception signal also expressed as a complex is taken as a numerator and the absolute value of the complex number is taken as amplitude and the argument is taken as phase It is. The sound data obtained by the above operation is shown in Table 1.

In order to reduce the influence of noise, it is conceivable to take a time average of a predetermined period when acquiring the amplitude a ₁₀ , the phase b ₁₀ , the amplitude a ₂₀ , and the phase b ₂₀ as sound data. Moreover, immediately after the installation of the terminal 2, there is also a method of providing a certain time from immediately after the installation of the terminal 2 to acquiring the sound data because the fluctuation of the adhesive or the like is large. These parameters can be arbitrarily set by the user as long as the timing is considered to be sufficiently early timing as compared with the deterioration rate of the structure 1 or the object on which the structure 1 is installed.

Next, the operation of the detection phase will be described. In the detection phase, the signal transmission / reception unit 21 transmits a transmission signal and receives a reception signal at a predetermined timing, as in the learning phase. If the S ₁₁ of a frequency f ₁ and frequency f ₂ obtained when the the detection data, the detection data is as shown in Table 2.

  The detection data is transmitted to the determination unit 23, and is compared with the sound data in the determination unit 23.

  Here, the principle by which a difference arises between detection data and sound data due to a crack, peeling, or contact of an object generated in the structure 1 will be described.

  When a crack or separation occurs in the structure to be installed, the structure 1 also has a crack or hole. A crack or a hole generated in the structure 1 becomes a fractured portion of the radio wave path from the electromagnetic wave propagating inside, and an open end electrically occurs. Since reflection in electromagnetic wave propagation occurs due to a sudden change in impedance, the open end created in the propagation path acts as a new reflecting surface. As a result, the waves reflected by the new reflection surface act on the received signal to cause a difference in the amplitude and phase of the detection data.

  In addition, it is considered that an object is in contact with the structure 1. When an object having a high dielectric constant contacts the surface, the electric field of the transmission signal propagating through the structure 1 changes to a healthy state, and the electric field is concentrated on the object having a high dielectric constant. As a result, the propagation loss and the effective electrical length in the contact area change, and the amplitude and the phase change. When metal contacts, an ideal reflective surface is generated on the surface of the structure 1, so that the propagation loss and the electrical length change.

  As a result, the amplitude and the phase of the electromagnetic wave received as the reception signal also change, and a difference occurs between the detection data and the sound data.

The determination unit 23 determines the presence or absence of a crack, peeling, or contact, that is, the presence or absence of a physical change generated in the structure, from the difference between the detection data and the sound data, using a predetermined threshold value. . In the present embodiment, the detection data and the sound data have amplitudes and phases respectively corresponding to the frequency f ₁ and the frequency f ₂ , so four threshold values are prepared as shown in Table 3.

If the value of the detection data exceeds the threshold value by any one of the four conditions of the amplitude a and the phase b of the frequency f ₁ and the frequency f ₂ , the determination unit 23 determines the threshold value. The notification unit 24 is notified of the exceeding. Here, the setting of the threshold size and the number of conditions for notifying the notification unit 24 can be arbitrarily set by the user, and can be set from the required values of the detection rate and the false detection rate. If the threshold is small, the notification unit 24 is notified with a slight difference, so the detection sensitivity is increased but the false detection rate is increased. Conversely, if the threshold value is set large, the detection sensitivity decreases, and notification to the notification unit 24 is not performed unless there is a large crack, peeling, or contact with a large object, but the false detection rate is reduced. In addition, as the threshold value, a value for the detection data may be set, or a value for the difference between the detection data and the sound data may be set.

  The notification unit 24 receives a notification from the determination unit 23 and performs a predetermined notification operation. Specifically, abnormality information indicating that a physical change has occurred in structure 1 (= object) is output. For example, it is conceivable to issue a detection notification wirelessly or the like, or it is possible to issue a detection notification by light emission, sound, etc., and can be set arbitrarily by the user.

  By the above operation, when the structure 1 is worn out or when an object comes in contact, it is possible to detect their occurrence. As described above, the structure 1 changes into various shapes depending on the installation place and the surface shape. In addition, since the terminal 2 is also installed at an arbitrary position of the structure 1, the sound data differs depending on the installation position. However, by providing the learning phase in advance and acquiring sound data in advance, even if the propagation state of the electromagnetic wave inside the structure 1 is different depending on the installation, it is possible to reduce wear and tear with reference to the sound propagation state. It is possible to detect contact.

  Although the electromagnetic wave is used as the transmission signal in the present embodiment, the detection of the frequency, the amplitude, and the phase of the sound wave is possible, and therefore, it is possible.

Moreover, in this embodiment, although the signal which consists of two frequency components of frequency f ₁ and frequency f ₂ was used, one or three or more frequency components may be sufficient. When the number of frequency components is one, there is an advantage that the configuration of the terminal 2 is simplified and the manufacturing cost is reduced, but the sensitivity decreases in the node portion of the electric field distribution in the electromagnetic wave propagation. When the frequency component is two or more, the configuration of the terminal 2 is complicated, but the position of the node of the above-mentioned electric field distribution is different for each frequency, and parts of desensitization can be complemented with each other. Lead to

Second Embodiment
FIG. 2 shows the configuration of a detection system according to the second embodiment. In this embodiment, a plurality of terminals 2 are installed at different locations, such as terminal 2a, terminal 2b, terminal 2c, etc., with respect to structure 1, and each terminal 2 (2a, 2b, 2c, The point that time change data of the reception signal is included in the signal transmitted from the reporting unit 24 of ...) is different from the first embodiment, and not only the notification of wear and tear, but also the position thereof can be identified. Become. In this embodiment, the case where three terminals 2 (2a, 2b, 2c) are installed for the structure 1 will be described.

  The specifications and operations of the structure 1 are the same as in the first embodiment. The three terminals 2a, 2b and 2c acquire sound data in the learning phase in the same manner as in the first embodiment in the learning phase. . The time for acquiring the time waveform is a start time immediately after transmission of the transmission signal, and an end time after an arbitrary time such as feedback. In the detection phase, the judgment unit 23 compares the sound data with the detection data using a threshold value, and notifies the notification unit 24 when wear or contact is detected from the comparison result. At this time, notification of the time waveform of the reception signal at the time of detection is also performed. That is, the reporting unit 24 reports detection and transmits the time waveform of the received signal at the time of sound and the time waveform of the received signal at the detection to an analysis unit (not shown in FIG. 2) such as a computer.

  The user of the present invention recognizes the wear and tear of the structure 1 by the notification from the notification unit 24 of each of the three terminals 2a, 2b and 2c, and carries out the following analysis. Specifically, in the analysis unit, the received signal at the time of sound notified from each terminal 2 and the received signal at the time of detection are compared for each terminal 2, and the time from the start of the time waveform to the appearance of the difference is measured Do. The distance is obtained by multiplying the propagation velocity by half of the measured time. From the distances obtained from the respective terminals 2, trigonometry is used to identify the places where wear and tear or contact has occurred.

  The principle of identifying the place or position where wear or contact has occurred by the above operation will be described. The path of the signal reflected on the reflecting surface newly generated due to wear and tear and returning to the terminal 2 at the earliest is a line segment connecting the terminal 2 and the newly generated reflecting surface. Therefore, when the transmission signal is observed starting from the time of generation, the difference in the time waveform of the reception signal at the time of sound and the reception signal at the time of detection is generated for the first time. It is considered that the time when the light reaches the reflection surface, is reflected, propagates on the line segment, and returns to the terminal 2. From the above, it is possible to obtain the distance between the terminal 2 and the newly generated reflecting surface by multiplying the propagation velocity by half of the time when the difference is observed for the first time.

  In the first and second embodiments, the electromagnetic wave has been described as an example. However, since the speed of sound is slower than the speed of light, using a sound wave makes the implementation easier and suitable.

Third Embodiment
FIG. 3 shows the configuration of a structure 1 according to the third embodiment. In the present embodiment, a conductive paint or a paint in which metal powder or metal flakes are mixed is used for the surface layer portion 11 and the adhesion portion (adhesion surface) 13 of the structure 1, and the inside 12 between the surface layer portion 11 and the adhesion portion 13 The second embodiment differs from the first and second embodiments in that it is an insulating paint.

  It is conceivable to use copper, silver, or aluminum powder as the powder contained in the conductive paint forming the surface layer portion 11 and the adhesion portion 13, but it is not limited to this as long as it is a substance that can conduct electricity. In addition, this three-layer structure may be formed by coating on a 1 m square concrete structure 100 to be measured, and when the object to be measured is a conductive material such as a steel pipe column, the conductive surface is electrically conductive It is not necessary to coat the conductive paint, and it may be formed of two layers of the insulating paint of the inside 12 and the conductive paint of the surface layer portion 11. The multilayer structure in which the insulator, the dielectric, and the insulator are stacked results in a structure in which the electromagnetic wave is confined in the structure 1, which makes it possible to propagate the electromagnetic wave in the parallel plate mode. The configuration is suitable for detection.

  The terminal 2 was connected to the coated surface (surface layer portion 11, adhesion portion 13) of the conductive paint of the structure 1 and installed. FIG. 4 is a diagram showing an example of physical connection between the structure 1 and the signal transmission / reception unit 21 of the terminal 2. In practice, the transmission signal and the reception signal in FIG. 1 referred to in the first embodiment physically perform transmission and reception on a single cable, and the signal line of the signal transmission / reception unit 21 Connect a ground wire to each conductive layer. The connection method is not limited to FIG. 4, and the signal line may be connected to the lower conductive layer (adhesion portion 13) and the ground line may be connected to the upper conductive layer (surface layer portion 11).

The operation and the like of the structure 1 are the same as in the first embodiment. The terminal 2 acquires sound data in the learning phase as in the first embodiment. In the present embodiment, for the purpose of detecting a 7 to 10 cm flaw, frequencies of 1 GHz and 750 MHz were used for the transmission signal. Also, sound data using a decibel of the absolute values of S _11, a value corresponding to each frequency were as shown in Table 4. At this time, amplitude or phase information may be used. Moreover, since the frequency to be used changes with sizes, such as a contact area to detect and a crack, you may use frequencies other than 1 GHz and 750 MHz.

  Further, in the detection phase, the judgment unit 23 compares the sound data with the detection data using the threshold value, and notifies the notification unit 24 when it detects wear or contact. Tables 5 and 6 show detection data and preset threshold values, respectively.

The determination unit 23, among the respective _{S 11} frequencies 1GHz and the frequency 750 MHz, if it exceeds any one any threshold is notified to the notification unit 24. The detection data in Table 5 is detection data actually measured by forming a 7 to 10 cm flaw in the structure 1, and the value of 1 GHz detection data exceeds the threshold in Table 6 From the above, it can be said that the existence of a scratch could be detected.

  The setting of the threshold size and the number of conditions for notifying the notification unit 24 can be set arbitrarily by the user, and can be set from the required values of the detection rate and the false detection rate, and is limited thereto I will not. If the threshold is small, the notification unit 24 is notified with a slight difference, so the detection sensitivity is increased but the false detection rate is increased. Conversely, if the threshold value is set large, the detection sensitivity decreases, and notification to the notification unit 24 is not performed unless there is a large crack, peeling, or contact with a large object, but the false detection rate is reduced.

  The notification unit 24 receives a notification from the determination unit 23 and performs a predetermined notification operation. For example, a case may be considered in which detection notification is issued wirelessly or the like, or detection notification may be issued by light emission or sound, etc., and can be set arbitrarily by the user. By the above-described operation, it is possible to detect when the structure 1 is worn out or when an object comes in contact.

  Finally, connection examples other than the connection example shown in FIG. 4 are shown in FIGS.

For example, as shown in FIG. 5, a transformer 3 may be connected between the structure 1 and the terminal 2. Further, as shown in FIG. 6, it is also conceivable to connect the structure 1 and the terminal 2 by using, for example, a three-port directional coupler 4. Specifically, the (+) and (-) transmission signal lines 6a and 6b on the signal transmission / reception unit 21 side are connected to the input port IN, and the (+) and (-) reception signal lines 7a and 7b are connected. connect to the reflection port OUT _0, connecting structure 1 side of the signal line 8a, the ground line 8b to the output port OUT _1. Directional coupler 4 reflects the transmission signal inputted to the input port IN and output (traveling wave) from the output port OUT _1, the received signal (reflected wave) which has returned from the structure 1 to the output port OUT ₁ port Output from OUT ₀

Besides, as shown in FIG. 7, for example, a 3-port circulator 5 may be used. The connection method is the same as the connection method shown in FIG. 6, but here, the input port IN is a first port P ₁ , the output port OUT ₁ is a second port P ₂ , and the reflection port OUT ₀ is a third port P. _Set to ₃ The circulator 5 is provided with a characteristic of outputting a signal in one direction between a plurality of ports, the input signal to the first port P ₁ (the transmission signal) is outputted to the second port P _2, the input from the second port P ₂ the output signal (reception signal) to the third port P _3, not transmitted in the opposite direction.

<Effect>
According to each embodiment, the structure 1 which has a surface shape corresponding to the surface shape of the installation location and in which a predetermined signal can be propagated, and the terminal installed at an arbitrary place of the structure 1 2, the terminal 2 transmits a signal to the inside of the structure 1, and receives the signal transmitted through the inside of the structure 1 as a reception signal, and the structure 1. Learning part 22 which stores data of the received signal in a state where there is no wear in 1 and there is no contact with any substance as sound data, and detects wear and contact with any substance caused to structure 1 Therefore, the judgment unit 23 judges the presence or absence of wear or contact of an arbitrary substance generated in the structure 1 by comparing the received signal regularly acquired with the sound data and detecting the presence or absence of the change, and the judgment Are sent to the outside according to the signal from Since the reporting unit 24 reports an abnormality that has occurred in the body 1, it is possible to planarly detect the occurrence of signs of deterioration in a structure such as a crack or peeling, and a social infrastructure with many concrete structures and the like. It contributes to the automation of the inspection work of houses and houses.

  Further, in each embodiment, the shape of the structure 1 can also be changed according to the surface shape to be detected, so that it can be easily applied to structures having various surface shapes, etc. Become. In addition to the structure, for example, it is also effective for sensing the risk of falling down at a mining excavation site or the like.

  Moreover, in each embodiment, the structure 1 is a sheet that can correspond to a paint or a flexible shape, and it is necessary to temporarily change the setting in a flexible manner because its construction is easy. It is suitable for laying of a no entry area or a braille block.

DESCRIPTION OF SYMBOLS 1 ... Structure 11 ... Surface part 12 ... Inside 13 ... Attachment part 2, 2a, 2b, 2c ... Terminal 21 ... Signal transmission / reception part 22 ... Learning part 23 ... Judgment part 24 ... Report part 3 ... Transformer 4 ... Directional coupling Unit 5: circulator 6a: transmission signal line of transmission signal (+) 6b: transmission signal line of transmission signal (-) 7a: reception signal line of reception signal (+) 7b: reception signal line of reception signal (-) 8a ... Signal line 8b: Ground line 100: Concrete structure

Claims (8)

In a detection system that detects physical changes in an object,
A structure molded into a shape according to the surface shape of the object and bonded to the surface of the object;
And a terminal installed at an arbitrary position of the structure.
The terminal is
A signal transmitting / receiving unit that transmits a signal inside the structure, and receives a signal propagated and returned inside the structure;
A learning unit for storing data of a received signal when there is no physical change in the structure;
A determination unit that determines the presence or absence of a physical change in the structure based on a comparison result of the data of the signal and the data of the signal received at a predetermined time;
A notification unit that outputs abnormal information when there is a physical change in the structure;
A detection system comprising: The physical change is
The detection system according to claim 1, wherein the detection system is a destruction that has occurred on the surface of the object or a contact of another object with the object. The signal is
The detection system according to claim 1, wherein the detection system is an electromagnetic wave or a sound wave, and includes a plurality of frequency components. The size of a quarter wavelength of the wavelength of the signal is
The detection system according to any one of claims 1 to 3, which is smaller than the magnitude of physical change of the structure. The structure is
The detection system according to any one of claims 1 to 4, wherein the detection system is a dielectric sheet or is made of a paint. The signal is an electromagnetic wave,
The structure is
The detection system according to claim 1, further comprising: a multilayer structure in which a dielectric is sandwiched between two conductive layers containing metal or metal powder, and the electromagnetic wave is propagated in a parallel plate mode by the dielectric. The plurality of terminals may be disposed at mutually different positions at arbitrary positions of the structure.
The reporting unit
The detection system according to any one of claims 1 to 6, further outputting temporal change data of a signal from the transmission to the reception of the structure. Physical of an object performed by a detection system including a structure molded into a shape according to the surface shape of the object and bonded to the surface of the object, and a terminal installed at an arbitrary position of the structure Detection method for detecting various changes,
The terminal is
Transmitting a signal inside the structure, receiving the signal propagating inside the structure and returning it;
Storing data of the received signal when there is no physical change in the structure;
Determining the presence or absence of a physical change in the structure based on the comparison result of the data of the signal and the data of the signal received at a predetermined time;
Outputting abnormal information when there is a physical change in the structure;
Detection method characterized in that.

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