JP2019158643A - Irregularity detection device, irregularity detection system, and irregularity detection method - Google Patents

Abstract

To discriminate information caused by an uneven shape of a surface of a metal base body from the reflected terahertz wave upon irradiating an object having a non-metal layer provided in an upper layer of the metal base body with a terahertz wave, and detect irregularity of the metal base body.SOLUTION: An irregularity detection device comprises: terahertz wave transmission means that is configured to be capable of irradiating a surface of an object having a non-metal layer provided in an upper layer of a metal base body with a terahertz wave, and scans on the surface of the object in association with a coordinate; terahertz wave reception means that is configured to be capable of receiving the terahertz wave reflected upon the object, and scans on the surface of the object in association with the coordinate; displacement measurement means that measures a relative displacement of a prescribed location of the surface of the object to create unevenness data on the surface of the object, and scans on the surface of the object in association with the coordinate; and analysis means that extracts an irregularity part of the surface of the metal base body from reception data on the terahertz wave obtained by the terahertz wave reception means and the unevenness data obtained by the displacement measurement means.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an abnormality detection device, an abnormality detection system, and an abnormality detection method for detecting an abnormality in an object using electromagnetic waves.

  In recent years, research and development of terahertz wave imaging and radar have been conducted, and application to non-destructive inspection and sensing is expected. The terahertz wave has a property that most of the terahertz wave is transmitted when irradiated to a non-metallic material such as a resin, and most of the terahertz wave is reflected when irradiated to a metal material. Conventionally, a technique for detecting an abnormality in the surface of a metal material layer existing in a lower layer of a non-metal material layer such as a resin layer by using the property of the terahertz wave has been studied.

  For example, Patent Document 1 discloses an irradiation unit that irradiates an object including a first member and a second member disposed on the first member, and reception that receives the terahertz wave reflected by the object. And an abnormality of the first member based on the reception state of the multiple reflection terahertz wave that is transmitted through the second member and reflected by the first member and then reflected a plurality of times on the inner side of the second member and on the first member An abnormality detection device is disclosed that includes a detection means for detecting the error. Further, Non-Patent Document 1 discloses an imaging apparatus based on an electronic device system of a reflective optical system using a resonant tunneling diode (RTD) that can perform two-dimensional imaging using the properties of terahertz waves. Is disclosed.

  In the above-described technique, in order to measure the unevenness of the surface of the metal material using the terahertz wave, that is, the distance to the surface, a pulse wave by the terahertz wave having a small time width is used in order to obtain a necessary measurement resolution. There is a need. However, in order to generate a terahertz pulse wave, a complicated mechanism is required. Then, the method of utilizing what is called a terahertz continuous wave which radiate | emits a terahertz wave continuously was examined. Since the terahertz continuous wave cannot use time information, it is difficult to measure the distance by TOF (Time of Flight). In view of this, a method for evaluating the unevenness of the surface of the object by using interference fringes caused by reflection of the terahertz continuous wave on the surface of the object made of a metal material or the like can be considered.

Japanese Patent Laid-Open No. 2006-75618

Satoshi Yamaguchi, “Development of Terahertz Imaging System”, PIONEER R & D (2014)

  However, a terahertz continuous wave is applied from the non-metal layer side to an object in which a layer made of a non-metal material such as a resin layer (hereinafter referred to as a non-metal layer) is provided on an upper layer of a metal material base (hereinafter referred to as a metal substrate). When irradiated, interference fringes are generated by the reflected wave on the surface of the metal substrate and the reflected wave on the surface of the non-metal layer, but it is extremely difficult to extract information on the irregular shape of the surface of the metal substrate from the generated interference fringes. It is. Therefore, there has been a demand for a technique capable of identifying information resulting from the uneven shape on the surface of the metal substrate and detecting an abnormality of the metal substrate.

  The present invention has been made in view of the above, and an object of the present invention is to provide a terahertz wave reflected by irradiating a terahertz wave from a non-metal layer side to an object provided with a non-metal layer on an upper layer of a metal substrate. An abnormality detection device, an abnormality detection system, and an abnormality detection method capable of identifying information caused by the uneven shape of the surface of the metal substrate from the measured terahertz wave information and detecting an abnormality of the metal substrate. It is to provide.

  (1) In order to solve the above-described problems and achieve the object, an abnormality detection device according to one embodiment of the present invention includes a terahertz wave at a predetermined position on the surface of an object provided with a non-metal layer on an upper layer of a metal substrate. The terahertz wave transmitting means configured to irradiate a wave, capable of scanning the surface of the object, and configured to receive the terahertz wave reflected at the predetermined position of the object, Terahertz wave receiving means capable of scanning while associating the surface of the object with coordinates, and measuring the relative displacement of the predetermined position of the surface of the object to generate unevenness data of the surface of the object And a displacement measuring means capable of scanning while associating the surface of the object with coordinates, and the reception data of the reflected terahertz wave obtained by the terahertz wave receiving means. , On the basis of the said uneven data obtained by the displacement measuring means, characterized in that it comprises, analyzing means for extracting the abnormal part of the surface of the metal substrate.

  (2) In the abnormality detection device according to one aspect of the present invention, in the invention according to (1), the analysis unit is configured to use the metal based on displacement information obtained by mapping the unevenness data corresponding to the surface of the object. Generating estimation information obtained when the surface of the substrate is normal, removing the estimation information from the terahertz wave information in which the received data is mapped in correspondence with the surface of the object, and the surface of the metal substrate The abnormal part is extracted.

  (3) The abnormality detection device according to one aspect of the present invention is characterized in that, in the invention of (1) or (2), the frequency of the terahertz wave is 0.3 THz or more and 0.6 THz or less.

  (4) The anomaly detection system according to one aspect of the present invention is configured to be able to irradiate a terahertz wave to a predetermined position on the surface of an object on which a non-metal layer is provided on an upper layer of a metal base, and the object Terahertz wave transmitting means capable of scanning the surface of the object, terahertz waves configured to receive the terahertz wave reflected at the predetermined position of the object, and capable of scanning while associating the surface of the object with coordinates The receiving means is configured to measure the relative displacement at the predetermined position on the surface of the object to generate uneven data on the surface of the object, and associates the surface of the object with coordinates. A terahertz wave measuring means comprising a displacement measuring means capable of scanning while receiving the reflected terahertz wave received data obtained by the terahertz wave receiving means, and Based on the unevenness data obtained by the displacement measuring means, the analyzing means for extracting an abnormal portion on the surface of the metal substrate is configured to be able to transmit and receive the received data and the unevenness data via a network. It is characterized by that.

  (5) An abnormality detection method according to an aspect of the present invention includes an irradiation step of irradiating a terahertz wave to a predetermined position while scanning a surface of an object in which a nonmetal layer is provided on an upper layer of a metal substrate, and the object Receiving the terahertz wave reflected at the predetermined position in association with the coordinates of the surface of the object, and measuring the relative displacement at the predetermined position while scanning the surface of the object, Displacement measurement step for acquiring unevenness data on the surface of an object in association with coordinates, reception data of the reflected terahertz wave obtained in the reception step, and the unevenness data obtained in the displacement measurement step And an analysis step of extracting an abnormal portion on the surface of the metal base.

  According to the abnormality detection apparatus, the abnormality detection system, and the abnormality detection method according to the present invention, the terahertz reflected by irradiating the object having the nonmetal layer on the metal substrate with the terahertz wave from the nonmetal layer side is reflected. When measuring a wave, it is possible to identify information resulting from the uneven shape on the surface of the metal substrate from the information of the reflected terahertz wave and detect an abnormality of the metal substrate.

FIG. 1 is a diagram showing an overall configuration of an abnormality detection apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram showing the configuration of the abnormality detection apparatus according to one embodiment of the present invention. FIG. 3 is a diagram showing an image generated by the anomaly detection device according to an embodiment of the present invention, in which (a) is a terahertz wave image, (b) is a steel pipe in a normal state, and a steel surface is In the case of smoothness, an estimated terahertz wave image image presumed to be generated by the presence of the resin layer, (c) is an image image obtained by the difference between (a) and (b).

  Hereinafter, an abnormality detection apparatus and an abnormality detection method according to an embodiment of the present invention will be described with reference to the drawings. In all the drawings of the following embodiment, the same or corresponding parts are denoted by the same reference numerals. Further, the present invention is not limited to the embodiment described below.

  FIG. 1 is a diagram showing an overall configuration of an abnormality detection apparatus 1 according to an embodiment of the present invention. FIG. 2 is a block diagram showing the configuration of the abnormality detection apparatus 1 according to this embodiment.

  As shown in FIG. 1, the abnormality detection apparatus 1 according to this embodiment includes a terahertz transmission / reception head 10, a displacement meter head 20, a scanner head 30, a terahertz transmission / reception controller 40, a displacement meter controller 50, a scanner controller 60, and an analysis. A control unit 70 is included. The abnormality detection device 1 detects an abnormality in the pipe 80 as an inspection object. The pipe 80 is cylindrical, but may be a columnar member other than the pipe. The pipe 80 is an example of an inspection object, and the inspection object is not necessarily limited to the pipe. Specifically, the object may be various objects in which a non-metal layer is formed on an upper layer of a predetermined surface of a base made of a metal material such as a steel structure having a coating.

The terahertz transmission / reception head 10 is controlled by the terahertz transmission / reception controller 40. The terahertz transmission / reception head 10 is configured to be capable of irradiating the surface of the pipe 80 with a terahertz wave, and includes a reflective terahertz wave measuring device configured to be able to detect a reflected terahertz wave. That is, the terahertz transmission / reception head 10 has both terahertz wave transmission means and terahertz wave reception means. Here, the terahertz wave is an electromagnetic wave belonging to a so-called terahertz region, which is around 1 terahertz (1 THz = 10 ¹² Hz), specifically, a frequency region of 100 GHz to 10 THz (10 ¹¹ to 10 ¹³ Hz). The terahertz region is a frequency region that combines light straightness and electromagnetic wave transparency. In this embodiment, the frequency of the terahertz wave can be selected according to the film thickness of the resin layer 82 on the surface of the pipe 80, and is preferably 0.3 THz or more and 0.6 THz or less. However, it is not necessarily limited to this range.

  The displacement meter head 20 is controlled by a displacement meter controller 50. The scanner head 30 is controlled by a scanner controller 60. The scanner head 30 is configured to be movable along the longitudinal direction (X-axis direction) of the pipe 80 by the tube axis direction moving mechanism 31. The scanner head 30 is configured to be movable along the circumferential direction (θ-axis direction) of the pipe 80 by the pipe circumferential direction moving mechanism 32 of the pipe 80. The coordinates (X, θ) of the pipe 80 along the pipe axis direction and the pipe circumferential direction can be defined by the pipe axis direction moving mechanism 31 and the pipe circumferential direction moving mechanism 32, respectively. Further, the terahertz transmission / reception head 10 and the displacement meter head 20 are fixed to a portion of the scanner head 30 on the pipe 80 side. Thereby, the terahertz transmission / reception head 10 and the displacement meter head 20 are configured to be able to scan the outer peripheral surface of the pipe 80 two-dimensionally by the movement of the scanner head 30.

  The analysis control unit 70 as a control unit controls the terahertz transmission / reception controller 40, the displacement meter controller 50, and the scanner controller 60 in an integrated manner. In this case, the analysis control unit 70 controls the terahertz transmission / reception controller 40, the displacement meter controller 50, and the scanner controller 60 in an integrated manner. Details of the analysis by the analysis control unit 70 as an analysis unit will be described later. In addition, the analysis control part 70 can also comprise separately the control part as a control means, and the analysis part as an analysis means. When the analysis control unit 70 is configured as a separate unit of the control unit and the analysis unit, the control unit and the analysis unit may be connected by wire such as a cable, or may be wirelessly connected through a network or the like.

  As shown in FIG. 2, the terahertz transmission / reception head 10 includes a terahertz wave transmitting unit 11 as a terahertz wave transmitting unit, a beam splitter 12, an objective lens 13, and a terahertz wave receiving unit 14 as a terahertz wave receiving unit. Configured. The terahertz wave transmission unit 11 that is a transmission optical system includes, for example, a terahertz wave generation element 111 including a resonant tunneling diode (RTD), a hemispherical lens 112, and a collimating lens 113. Composed. Note that a photoconductive antenna (PCA) may be used instead of the resonant tunneling diode. The terahertz wave receiving unit 14 as a receiving optical system includes a condenser lens 141, a hemispherical lens 142, and a terahertz wave detecting element 143.

  During the operation of the abnormality detection device 1 according to this embodiment, a terahertz wave is emitted from the terahertz transmission / reception head 10. Specifically, the terahertz wave generated in the terahertz wave generating element 111 is emitted as a terahertz wave through the hemispherical lens 112 and the collimating lens 113. Here, the emitted terahertz wave is typically a continuous terahertz wave that is emitted continuously, but may be a terahertz pulse wave or a tone burst wave that is emitted intermittently.

  The terahertz wave emitted from the terahertz wave transmission unit 11 passes through the beam splitter 12 and is irradiated to a predetermined position on the surface of the pipe 80 through the objective lens 13. The pipe 80 is configured by providing a resin layer 82 as a non-metal layer as an upper layer on the surface of a steel pipe 81 as a metal substrate (hereinafter, steel surface 81a). The resin layer 82 functions as an anticorrosion layer. Most of the terahertz waves irradiated from the resin layer 82 side to the pipe 80 are reflected by the steel surface 81a. A part of the terahertz wave irradiated to the pipe 80 is reflected by the surface 82 a of the resin layer 82.

  The reflected terahertz wave is incident on the beam splitter 12 via the objective lens 13. The terahertz wave is reflected by the beam splitter 12 and introduced into the terahertz wave receiving unit 14 serving as a terahertz wave receiving unit. In the terahertz wave receiving unit 14, terahertz waves corresponding to the shapes of the steel surface 81 a and the surface 82 a of the resin layer 82 are detected. That is, the terahertz waves collected by the condensing lens 141 are collected by the hemispherical lens 142 to the terahertz wave detecting element 143, and a signal corresponding to the intensity of the terahertz waves is detected. Thereby, the reflected terahertz wave can be measured.

  The displacement meter head 20 constituting the displacement measuring means includes a conventionally known non-contact type laser displacement meter or a conventionally known contact displacement meter. Preferably, a non-contact type laser displacement meter including a light source capable of irradiating laser light and a light receiving element (none of which is shown) that focuses the laser light reflected by the pipe 80 to form an image is provided. . The displacement meter head 20 measures the relative displacement of the surface of the pipe 80 by irradiating the pipe 80 with the laser beam 25. The displacement meter controller 50 constituting the displacement measuring means supplies power to the displacement meter head 20 and outputs control signals to components inside the head. At the same time, the displacement meter controller 50 generates unevenness data on the surface of the pipe 80 from the relative displacement measurement value (relative displacement data) supplied from the displacement meter head 20. The displacement meter controller 50 supplies the generated unevenness data to the analysis control unit 70.

  A scanner head 30 as a scanning unit includes a tube axis direction moving mechanism 31, a tube circumferential direction moving mechanism 32, and a carriage 33. The carriage 33 is provided with the terahertz transmission / reception head 10 and the displacement meter head 20. Then, the carriage 33 moves two-dimensionally along the surface of the pipe 80 by driving the pipe axis direction moving mechanism 31 and the pipe circumferential direction moving mechanism 32 configured by, for example, a ball screw or a stepping motor. Thereby, scanning by the terahertz wave transmitting / receiving head 10 and the displacement meter head 20 fixed to the carriage 33 is performed.

  The scanner controller 60 generates drive signals for the tube axis direction moving mechanism 31, the tube circumferential direction moving mechanism 32, and the carriage 33 in the scanner head 30. Also, the scanner controller 60 monitors the terahertz wave at which the terahertz transmission / reception head 10 is receiving the terahertz wave on the surface of the pipe 80 as a result of the drive as well as the generation of the drive signal. Generate position data. If no reflected wave is observed, the coordinates of the position irradiated with the terahertz wave are the coordinates at which the terahertz wave having a reflectance of 0 is received. Similarly, the scanner controller 60 generates the drive signal and, as a result of the drive, the position of the laser beam from which position the displacement meter head 20 receives the laser light from the surface of the pipe 80, in other words, at which coordinate of the pipe 80. Displacement measurement position data including coordinates is generated by monitoring whether displacement is being measured.

  The terahertz transmission / reception controller 40 performs various controls on the terahertz transmission / reception head 10 and processes signals detected by the terahertz transmission / reception head 10. The terahertz transmission / reception controller 40 includes a signal amplification unit 41, a bias generation unit 42, a lock-in detection unit 43, and a recording unit 44. The signal amplification unit 41 amplifies the signal detected by the terahertz wave reception unit 14 and outputs the amplified signal to the lock-in detection unit 43 as terahertz wave reception data. The bias generation unit 42 generates a bias voltage to bias the terahertz wave generation element 111 and the terahertz wave detection element 143, and changes the terahertz wave transmitted or received according to the bias voltage. The terahertz wave transmitted or received by the terahertz wave generating element 111 and the terahertz wave detecting element 143 may be weak. In this case, lock-in detection is used for detecting the terahertz wave. At the time of lock-in detection, the terahertz wave transmission unit 11 uses the reference signal modulated as the bias voltage of the terahertz wave generation element 111 to remove the noise component of the terahertz wave detection signal. The recording unit 44 records the detected terahertz wave reception data while being associated with the terahertz imaging position data.

  The terahertz imaging position data generated by the scanner controller 60 is associated with the terahertz wave reception data by the terahertz transmission / reception controller 40. Similarly, the displacement measurement position data generated in the scanner controller 60 is associated with the unevenness data by the displacement meter controller 50. These terahertz imaging position data, terahertz wave reception data, displacement measurement position data, and concavo-convex data are respectively stored in the recording unit 44 and then supplied to the analysis control unit 70. When the analysis control unit 70 is configured separately from the control unit and the analysis unit, the terahertz imaging position data and the displacement measurement position data generated by the scanner controller 60 can be supplied to the analysis unit as position information. You may store in the predetermined recording part in a control part in a state.

  The analysis control unit 70 includes an image processing unit 71. The terahertz imaging position data and terahertz wave reception data recorded in the recording unit 44 are supplied to the image processing unit 71 in association with each other. The image processing unit 71 generates a terahertz wave image image mapped in correspondence with the surface of the pipe 80 based on the terahertz imaging position data including the coordinates and the terahertz wave reception data. Further, the displacement measurement position data and the unevenness data are supplied to the image processing unit 71 in association with each other. The image processing unit 71 maps an estimated terahertz wave image image (hereinafter referred to as an estimated terahertz wave image image) mapped in correspondence with the surface of the pipe 80 based on displacement measurement position data including coordinates and displacement information including unevenness data. ) Is generated. The estimated terahertz wave image image as the estimation information is an image image that is estimated to be generated when the steel pipe 81 is in a normal state and the steel surface 81a is smooth using the unevenness data measured in the resin layer 82. .

  FIG. 3A shows an example of a terahertz wave image image generated by the image processing unit 71. The terahertz wave image image 200 as terahertz wave information includes a reflected wave from the steel surface 81a, a reflected wave from the surface 82a of the resin layer 82, and a luminance distribution obtained by combining interference fringes generated by these reflected waves.

  As shown in FIG. 3A, in the terahertz wave image image 200, the interference fringes 201 are obtained by irradiating the surface of the pipe 80 with the terahertz continuous wave. The interference fringes 201 themselves occur even if the steel surface 81a and the surface 82a of the resin layer 82 in the pipe 80 are substantially completely flat or curved surfaces (hereinafter referred to as surfaces). If the steel surface 81a is smooth and the thickness of the resin layer 82 is uniform, the interference fringes 201 have a regular stripe pattern. On the other hand, when the abnormal part which consists of unevenness exists in either the steel surface 81a and the surface 82a of the resin layer 82, an irregular spot pattern appears in the terahertz wave image image 200. In FIG. 3A, irregular spots 202, 203, and 204 are generated. These spotted patterns 202 to 204 are abnormal portions due to any unevenness on the steel surface 81 a and the surface 82 a of the resin layer 82.

  FIG. 3B shows an example of an estimated terahertz wave image image generated by the analysis control unit 70 when the steel pipe 81 is in a normal state and the steel surface 81a is smooth. Based on the unevenness data of the surface 82a of the resin layer 82, which is the surface of the pipe 80, generated by the displacement meter controller 50, the analysis control unit 70 has a smooth steel surface 81a and the steel pipe 81 is not thinned. Then, an interference fringe 201 that is estimated to be generated is generated. In addition, when the generation state of the interference fringe 201 is estimated by the analysis control unit 70, at least one point of the resin layer 82 is used as necessary using a conventionally known contact-type film thickness measuring device (not shown). The absolute value of the film thickness is measured. Accordingly, the thickness of the entire surface of the resin layer 82 can be calculated from the absolute value of the measured film thickness at at least one point and the unevenness data based on the measured relative displacement data. Here, in the example shown in FIG. 3B, as the estimated terahertz wave image image 210, the singular part 211 and the interference fringes 201 expressed by the unevenness of the surface 82a of the resin layer 82 are obtained. As in FIG. 3A, the interference fringes 201 have a regular stripe pattern as long as the steel surface 81a is smooth and the thickness of the resin layer 82 is uniform.

  Based on the terahertz wave image image 200 shown in FIG. 3A and the estimated terahertz wave image image 210 shown in FIG. 3B, the analysis control unit 70 applies a portion that is not caused by a change in the film thickness of the resin layer 82. Extract. FIG. 3C illustrates an image obtained by subtracting the estimated terahertz wave image image 210 illustrated in FIG. 3B from the terahertz wave image image 200 illustrated in FIG.

  As illustrated in FIG. 3C, the analysis control unit 70 removes the singular part 211 and the interference fringes 201 in the estimated terahertz wave image image 210 from the speckle patterns 202 to 204 of the terahertz wave image image 200, thereby causing abnormalities. A partial image 220 is generated. That is, the abnormal part image 220 is an image obtained by removing the singular part 211 and the interference fringes 201 caused by the change in the surface 82a of the resin layer 82 from the terahertz wave image 200. As a result, the analysis control unit 70 can determine that an abnormal portion at the interface between the steel surface 81a or the steel pipe 81 and the resin layer 82 is generated in the spots 203 and 204.

  According to this embodiment described above, the measurement position is measured by the terahertz transmission / reception head 10 and the displacement meter head 20 from the resin layer 82 side with respect to the steel pipe 81 having the resin layer 82 for corrosion prevention on the surface. , The surface of the pipe 80 is scanned for each coordinate. As a result, information obtained by the terahertz transmission / reception head 10 at each coordinate (X, θ) and information on the unevenness of the surface 82a of the resin layer 82 obtained by the displacement meter head 20 can be collected together. . The information obtained by the terahertz wave transmitting / receiving head 10 is obtained as a terahertz wave image image 200 by the unevenness of the steel surface 81a and the surface 82a of the resin layer 82. Then, the steel in the lower layer of the resin layer 82 is compared by referring to the terahertz wave image image 200 and the estimated terahertz wave image image 210 estimated from the unevenness data of the resin layer 82 obtained by the displacement meter head 20. It is possible to extract unevenness information of the surface 81a. Therefore, an abnormal portion of the steel surface 81a inside the pipe 80 can be found without peeling off the resin layer 82.

  Although one embodiment of the present invention has been specifically described above, the present invention is not limited to the above-described embodiment, and various modifications based on the technical idea of the present invention are possible. For example, the configuration of the terahertz wave transmitting / receiving apparatus described in the above-described embodiment is merely an example, and an apparatus having a different configuration may be used as necessary. In addition, the present invention is not limited by the description and drawings which form part of the disclosure of the present invention according to the above-described embodiment.

  For example, in the above-described embodiment, the abnormality detection device 1 has been described. That is, the terahertz transmission / reception head 10, the displacement meter head 20, the scanner head 30, the terahertz transmission / reception controller 40, the displacement meter controller 50, and the scanner controller 60 can be integrated into a terahertz wave measuring instrument. In this case, the analysis control unit 70 may be composed of a personal computer or the like. When the terahertz wave measuring instrument and the analysis control unit 70 are separated, the terahertz wave measuring instrument and the analysis control unit 70 are configured to transmit and receive data via a network such as the Internet or an intranet (registered trademark). Is possible. That is, the terahertz wave reception data and the relative displacement data on the surface of the pipe 80 are acquired by the terahertz wave measuring instrument while being associated with the coordinates (X, θ) of the surface of the pipe 80, and separate analysis control is performed via the network. You may comprise so that it may supply to the part 70. FIG. In this case, the terahertz wave measuring instrument as the terahertz wave measuring means and the analysis control unit 70 constitute an abnormality detection system.

  In the above-described embodiment, the analysis control unit 70 generates the mapped terahertz wave image image based on the terahertz imaging position data and the terahertz wave reception data, but instead of the terahertz wave image image, the terahertz wave image image is generated. The imaging position data and the terahertz wave reception data may be numerical data. Similarly, the analysis control unit 70 generates the mapped estimated terahertz wave image image based on the displacement information such as the displacement measurement position data and the unevenness data, but the displacement measurement is performed instead of the estimated terahertz wave image image. Position data, displacement information, and the like may be numerical data.

  In the above-described embodiment, the displacement meter controller 50 generates the unevenness data on the surface of the pipe 80 from the relative displacement data that is the measurement value of the relative displacement. Concavity and convexity data may be generated. In this case, relative displacement data is supplied from the displacement meter controller 50 or the displacement meter head 20 to the analysis control unit 70.

DESCRIPTION OF SYMBOLS 1 Abnormality detection apparatus 10 Terahertz transmission / reception head 11 Terahertz wave transmission part 14 Terahertz wave reception part 20 Displacement meter head 30 Scanner head 40 Terahertz transmission / reception controller 50 Displacement meter controller 60 Scanner controller 70 Analysis control part 80 Piping 81 Steel pipe 81a Steel surface 82 Resin layer 82a Surface 200 Terahertz wave image image 201 Interference fringes 202, 203, 204 Spot pattern 210 Estimated terahertz wave image image 211 Singular part 220 Abnormal part image image

Claims (5)

A terahertz wave transmitting means configured to irradiate a terahertz wave to a predetermined position on the surface of the object provided with a non-metal layer on the upper layer of the metal substrate; and capable of scanning the surface of the object;
A terahertz wave receiving means configured to receive the terahertz wave reflected at the predetermined position of the object, and capable of scanning while associating the surface of the object with coordinates; and
Displacement capable of measuring the relative displacement at the predetermined position of the surface of the object and generating unevenness data of the surface of the object, and capable of scanning while associating the surface of the object with coordinates Measuring means;
Analyzing means for extracting an abnormal portion on the surface of the metal base based on the reception data of the reflected terahertz wave obtained by the terahertz wave receiving means and the unevenness data obtained by the displacement measuring means; An abnormality detection device comprising:   The analysis means generates estimation information obtained when the surface of the metal substrate is normal based on displacement information obtained by mapping the unevenness data corresponding to the surface of the object, and the received data is used as the object. The abnormality detection apparatus according to claim 1, wherein the abnormal information on the surface of the metal base is extracted by removing the estimation information from the terahertz wave information mapped corresponding to the surface of the object.   The abnormality detection apparatus according to claim 1, wherein a frequency of the terahertz wave is 0.3 THz or more and 0.6 THz or less. A terahertz wave transmitting means configured to be able to irradiate a terahertz wave to a predetermined position on the surface of an object provided with a non-metal layer on an upper layer of a metal substrate, and capable of scanning the surface of the object, The terahertz wave reflected at the predetermined position is configured to be receivable, the terahertz wave receiving means capable of scanning while associating the surface of the object with coordinates, and the predetermined position of the surface of the object A terahertz wave measuring unit comprising a displacement measuring unit configured to measure relative displacement and generate unevenness data on the surface of the object, and to scan while correlating the surface of the object with coordinates. When,
Analyzing means for extracting an abnormal portion on the surface of the metal base based on the reception data of the reflected terahertz wave obtained by the terahertz wave receiving means and the unevenness data obtained by the displacement measuring means; ,
An anomaly detection system configured to be able to transmit and receive the received data and the unevenness data via a network. An irradiation step of irradiating a predetermined position with a terahertz wave while scanning the surface of an object on which a non-metal layer is provided on an upper layer of a metal substrate;
Receiving the terahertz wave reflected at the predetermined position in the object while associating it with the coordinates of the surface of the object;
A displacement measuring step of measuring the relative displacement of the predetermined position while scanning the surface of the object, and acquiring the unevenness data of the surface of the object in association with coordinates;
An analysis step of extracting an abnormal portion on the surface of the metal base based on the reception data of the reflected terahertz wave obtained in the reception step and the unevenness data obtained in the displacement measurement step. An abnormality detection method characterized by the above.

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