JP2019011994A - Displacement measuring device, displacement measuring method, and program - Google Patents

Abstract

Disclosed is a displacement measuring device or the like that can accurately measure a displacement of a measurement object and intuitively understand the displacement using a captured image obtained by photographing the measurement object. A displacement measuring apparatus 10 that measures a displacement when a measurement target is vibrated based on a captured image of the measurement target photographed by an imaging unit 20, and is continuously photographed by the imaging unit 20 every predetermined time. Displacement information calculation unit 35 that obtains a plurality of captured images of the measurement target and displacement information from the reference positions of the plurality of measurement points of the measurement target in time series based on the plurality of captured images And a smoothing processing unit 37 that smoothes displacement information of a plurality of measurement points at predetermined time intervals using a smoothing filter. [Selection] Figure 2

Description

  The present invention relates to a displacement measuring device, a displacement measuring method, and a program.

  As disclosed in Patent Documents 1 and 2, there is known a method for grasping physical properties such as strength of concrete by measuring the elastic wave velocity propagating inside when hitting the surface of a concrete structure. Yes.

  In the method for diagnosing the deterioration of a floor slab based on the elastic wave velocity ratio of Patent Document 1, a method for estimating the progress of cracks and deterioration from a decrease in elastic wave velocity is shown. This document describes a method of hitting a floor slab with a steel hammer as a method of generating a shock elastic wave.

  On the other hand, in Patent Document 2, as a simple vibration method for the walls of bridges and tunnels, a large amount of vibration can be applied even in places where the inspector's hand cannot reach easily by throwing gunpowder toward the target point. A method by which force can be generated is described.

  On the other hand, as disclosed in Patent Document 3, a laser beam is emitted toward a reflector (target) installed on a measurement target such as a bridge or a wall surface of a building, and the reflected laser beam is received. 2. Description of the Related Art Displacement measuring devices that measure vibration and deflection of a measurement object without contact are known.

  Recently, with the widespread use of high-quality, high-sampling rate video cameras such as 4K high-speed cameras, technology has been developed to detect various movements of various objects by analyzing captured image data. Technology is beginning to be applied to building displacement detection.

JP 2014-149285 A Japanese Patent Laying-Open No. 2015-203572 JP 2017-53772 A

  However, in the prior art described in Patent Documents 1-3, it is necessary to attach a sensor or a target to a measurement target. When a slant (cable) of a long-span bridge or a cable-stayed bridge is a measurement target, these are attached. It becomes difficult. On the other hand, when a 4K high-speed camera or the like is used, it is not necessary to install a target or the like. However, the amount of image data is enormous, and it may be difficult to intuitively understand the movement of the measurement target. .

  The present invention has been made in view of the above circumstances, and uses a captured image obtained by photographing a measurement object to accurately measure the displacement of the measurement object and to intuitively understand the displacement. The object is to provide a device.

  In order to achieve the above object, the displacement measuring device of the present invention is a displacement measuring device that measures the displacement when the measuring object is vibrated on the basis of a captured image obtained by photographing the measuring object. An image information acquisition unit that acquires a plurality of captured images of the measurement object continuously captured, and displacement information from a reference position of the plurality of measurement points of the measurement object based on the plurality of captured images. A displacement information calculation unit that calculates in series is provided, and a smoothing processing unit that smoothes the displacement information of the plurality of measurement points every predetermined time by a smoothing filter.

  Here, based on the displacement information of the plurality of measurement points that have been smoothed, a configuration including an image generation unit that generates a three-dimensional image representing the displacement of the measurement object in time series and displays it on a display unit It can be. The smoothing processing unit may be configured to smooth the displacement information by an order based on the total number of measurement points. Furthermore, the measurement object is a beam-like structure in which corners of a rectangular beam in plan view are supported by a plurality of supports, and the plurality of measurement points smoothed by the smoothing processing unit. A support state detection unit that detects a support state of the beam by the support based on the displacement information may be provided.

  Further, the displacement measuring method of the present invention is a displacement measuring method performed by the displacement measuring apparatus as described above, and a step of acquiring a plurality of captured images of the measurement object continuously photographed every predetermined time; A step of calculating displacement information from a reference position of a plurality of measurement points of the measurement object in time series based on the plurality of captured images, and a smoothing filter for the displacement information of the plurality of measurement points for each predetermined time And a smoothing step.

  Further, the program of the present invention includes a computer that acquires a plurality of captured images of a measurement target that are continuously captured every predetermined time, and a plurality of measurements of the measurement target based on the plurality of captured images. A program for functioning as means for calculating displacement information from a reference position of a point in time series and means for smoothing the displacement information of the plurality of measurement points every predetermined time by a smoothing filter.

  The displacement measuring apparatus of the present invention configured as described above calculates displacement information of a plurality of measurement points of the measurement target based on a plurality of captured images of the measurement target that are continuously photographed every predetermined time. Therefore, displacement information at more measurement points can be calculated in time series from a plurality of high-quality captured images. Then, by smoothing the calculated displacement information using a smoothing filter, noise of displacement information that differs depending on the measurement point can be accurately removed. Therefore, it is possible to accurately measure the displacement of the measurement object and intuitively understand the displacement using the captured image obtained by photographing the measurement object.

  Further, if the configuration is to generate and display a three-dimensional image representing the displacement of the measurement object in time series based on the smoothed displacement information of the plurality of measurement points, the measurer displays the displacement of the measurement object, It can be understood more intuitively through vision. In addition, if the displacement information is smoothed by the order based on the total number of measurement points, appropriate smoothing according to the total number of measurement points is possible, and the displacement can be measured more accurately and the displacement can be made more intuitive. Can be understood.

  In addition, when the measurement target is a beam-like structure in which the corners of a rectangular beam in plan view are supported by a plurality of supports, the support is based on the displacement information of a plurality of smoothed measurement points. It is possible to detect the support state of the girders. Since the displacement of the beam-like structure can be measured accurately and the displacement can be understood intuitively, the support state of the girder by the support, such as the three-point support state, can be detected more accurately and the support state Can be understood intuitively.

It is a figure for demonstrating the whole structure and measurement condition of the displacement measuring device of 1st Embodiment. It is a functional block diagram showing the function of the displacement measuring apparatus shown in FIG. After the model bridge is subjected to shock excitation, the original displacement data before smoothing at a certain point is plotted to represent the deformed shape, and the displacement data after smoothing is plotted to represent the deformed shape. It is a graph. It is a figure which shows an example of the three-dimensional image of the displacement waveform produced | generated based on the displacement data measured by impact excitation of the model bridge and each measurement point. It is a figure which shows an example of the three-dimensional image of the displacement waveform produced | generated based on the displacement data after a smoothing process. It is a flowchart which shows an example of the process of the displacement measuring method performed with the displacement measuring apparatus of 1st Embodiment. It is a figure for demonstrating the three-point support state in a bridge. It is a figure which shows a three-dimensional image when the displacement of the model bridge of a three-point support state is measured with the displacement measuring apparatus of 1st Embodiment. It is a figure which shows a three-dimensional image when the displacement of the model bridge of the healthy state which does not float is measured with the displacement measuring apparatus of 1st Embodiment. It is a figure which shows a three-dimensional image when the displacement of the model bridge of a three-point support state is measured with the displacement measuring apparatus of 2nd Embodiment. It is a figure which shows a three-dimensional image when the displacement of the model bridge of the healthy state without a float is measured with the displacement measuring apparatus of 2nd Embodiment.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram for explaining the overall configuration and measurement status of the displacement measuring apparatus 10 of the first embodiment. FIG. 2 is a functional block diagram showing functions of the displacement measuring apparatus 10.

  The displacement measuring apparatus 10 according to the present embodiment measures displacement such as vibration or deformation of a measurement target. The object to be measured is any structure or form as long as displacement occurs, such as a beam-like structure such as a bridge girder of a bridge, a structure such as a building or a retaining wall, or a feature such as a ground, a slope, or a bedrock. Also good.

  In FIG. 1, the RC girder 2 of the bridge 1 is illustrated as a measuring object. The RC girder 2 is a concrete structure having a rectangular shape in plan view, and is spanned between the piers 3 and 3. The RC girder 2 vibrates due to an impact caused by running of the train T, for example.

Further, the object to be measured may be an elongated object such as a cable stayed cable (cable). For example, when the measurement target is a cable-stayed bridge or a long-span bridge, it may be difficult to photograph a portion where the displacement is to be measured. In such a case, for example, a captured image obtained by photographing an oblique material can be used.
be able to.

  As shown in FIG. 1, the displacement measuring apparatus 10 according to this embodiment includes an imaging unit 20 that continuously captures captured images of a structure to be measured every predetermined time, and imaging that is sequentially input from the imaging unit 20. Based on the image, the calculation unit 30 that calculates the displacement of the measurement target and the cable 40 that connects the imaging unit 20 and the calculation unit 30 are configured.

  In the present embodiment, the imaging unit 20 and the calculation unit 30 transmit and receive captured images and the like via the cable 40, but are not limited to this. For example, image data can be transmitted and received using short-range wireless communication such as Bluetooth (registered trademark) or wireless LAN communication such as WiFi (registered trademark).

  The imaging unit 20 includes an imaging optical system that forms a subject image of a structure, an imaging device such as a CCD or CMOS that converts the subject image into an electrical signal, and outputs the electrical signal. The imaging unit 20 is not particularly limited as long as the captured image of the structure can be continuously captured every predetermined time and output as image data, but in order to accurately measure the displacement, It is desirable to use a digital video camera with high image quality and high sampling rate. More specifically, it is desirable to use a digital video camera having a resolution of 720 × 480 or higher and a sampling frequency (frame rate frequency) of 60 Hz or higher. In this embodiment, a digital video camera having a resolution of 1,920 × 600, a sampling frequency of 120 Hz, and a high sampling rate is used.

  The captured image captured by the imaging unit 20 may be a still image captured continuously every predetermined time or a frame image of a moving image.

  The imaging unit 20 may be held by a measurer and photographed. However, in the present embodiment, as shown in FIG. 1, the imaging unit 20 is supported by a tripod 21 and fixed to the ground or the like. By taking a picture, blurring and the like are suppressed. The imaging unit 20 can be mounted on a small unmanned aerial vehicle such as a drone so that a measurement object such as a structure can be photographed from the air. Can be taken.

  As the arithmetic unit 30, for example, a personal computer (PC) that includes a display unit 31 such as a liquid crystal display and an operation unit 32 such as a keyboard and a mouse and incorporates a CPU, RAM, ROM and the like can be used. As the PC, a desktop PC may be used, but since it is lightweight and excellent in portability, a notebook PC is used in this embodiment.

  As shown in FIG. 2, the calculation unit 30 includes a control unit (CPU) 33 that controls the operation of the displacement measuring apparatus 10 as a whole, and a storage unit that stores various programs and data including RAM, ROM, flash memory, HDD, and the like. 34 and the like. The control unit 33 controls the entire displacement measuring apparatus 10 according to the program stored in the storage unit 34. Further, the control unit 33 executes the displacement measurement method according to the displacement measurement program stored in the storage unit 34. That is, the control unit 33 also functions as an image information acquisition unit 35, a displacement information calculation unit 36, a smoothing processing unit 37, and a display image generation unit 38.

  The image information acquisition unit 35 acquires image data of a measurement target captured image input from the imaging unit 20. At this time, the image information acquisition unit 35 performs necessary image processing and processing (for example, coordinate conversion, contrast adjustment, color conversion, brightness adjustment, filter processing, etc.) on the acquired image data. The acquired image data is stored in the storage unit 34 and transferred to the displacement information calculation unit 36. Note that the storage in the storage unit 34 may be temporarily stored in the volatile memory or may be stored in the nonvolatile memory. The same applies to the displacement data and display image data described below.

  The displacement information calculation unit 36 determines in advance a plurality of measurement points to be measured for each piece of image data using a suitable image analysis tool for a plurality of pieces of image data obtained by the image information acquisition unit 35 every predetermined time. Displacement information (displacement data) from the predetermined reference position is calculated. Thereby, displacement data of a plurality of measurement points can be acquired in time series. That is, the displacement data is represented as spatio-temporal data having a spatial direction (direction of the position of the measurement point) and a time direction (time axis direction of imaging). The calculated displacement data is stored in the storage unit 34 and transferred to the smoothing processing unit 37.

  In order to measure the displacement with higher accuracy, for example, it is desirable to set a large number of locations in the longitudinal direction of the RC beam 2 as measurement points. More specifically, the number of measurement points is preferably more than 100 points, more preferably 200 points or more, and it is desirable to measure so-called large-scale multipoint displacement data. By using a picked-up image taken by the image pickup unit 20 with high image quality and a high sampling rate, it is possible to acquire such large-scale multi-point displacement data. Based on this large-scale multi-point displacement data, the displacement can be measured with higher accuracy.

  Here, the vibration shape of a beam-like object to be measured such as a bridge can be explained by a translational / rotational component in which the entire bridge is a rigid body and a bending component of the beam represented by a sine wave. However, in large-scale multi-point displacement data, noise and measurement accuracy are different at each measurement point, so that it is difficult to read each component as described above from the obtained displacement data. Also, the amount of large-scale multipoint displacement data obtained in time series is enormous, and it is difficult to intuitively understand the movement of the measurement object simply by two-dimensionally plotting the measurement results.

  In view of this, the inventor pays attention to the property that “the displacement shape in the line direction is continuous in the beam-like structure, and the displacement of any two adjacent points does not differ greatly at any point in time”. We came up with the idea of smoothing the displacement data in the spatial direction, not in the time direction. Thus, the noise is accurately removed and the movement of the measurement object can be intuitively understood.

  Therefore, the smoothing processing unit 37 smoothes the displacement data at a plurality of measurement points for each predetermined time using a smoothing filter based on the displacement data calculated by the displacement information calculation unit 36. By this smoothing process, different noise at each measurement point can be accurately removed. The smoothing method using the smoothing filter is not particularly limited, but moving average filter processing using a moving average filter and median filter processing using a median filter are suitable.

  In the displacement data, which is spatiotemporal data, the spatial direction and the temporal direction are independent. Therefore, smoothing processing is performed only in the spatial direction using a spatial moving average filter or median filter instead of a normal two-dimensional moving average filter or median filter.

  In the smoothing process, it is desirable to smooth the displacement data with an order based on the total number of measurement points. For example, when the number of measurement points is more than 100 and less than 200, the order is 1/10 of the total number of measurement points, and a 1 / 10th order moving average filter or a 1 / 10th order median filter is used. It is desirable to perform smoothing processing. When the total number of measurement points is 200 or more, it is desirable to set the order to 20 and perform the smoothing process using a 20th order moving average filter or a 20th order median filter. This is based on the fact that the displacement of the RC girder 2 which is a beam-like structure does not change discontinuously, and that the deformed shape can be expressed up to about the third bending deformation.

  The display image generation unit 38 generates a three-dimensional image that represents the displacement of the measurement object in time series based on the smoothed displacement data of the plurality of measurement points, and displays it on the display unit 31 (for example, FIG. 5). FIG. 8 to FIG. 11).

  Next, a displacement measuring method performed by the displacement measuring apparatus 10 of the present embodiment will be described based on the flowchart of FIG. When performing displacement measurement, first, as shown in FIG. 1, the displacement measuring device 10 is installed at a position where the entire image of the RC girder 2 of the bridge 1 to be measured can be captured by the imaging unit 20. After that, the arithmetic unit 30 is activated and the operation unit 32 is operated to activate the displacement measurement program, and the imaging unit 20 is activated to start photographing the RC digit 2. Here, a moving image is taken.

  Then, the imaging unit 20 captures an image of how the RC girder 2 vibrates due to impact excitation. This impact excitation may be caused by, for example, traveling of the train T or the like, or may be caused by hitting the RC girder 2 with a hammer or the like. Displacement measurement processing is started by outputting image data of the captured image from the imaging unit 20 to the calculation unit 30. The output of the image data may be performed in real time corresponding to the shooting of the moving image, or may be output at once after the shooting of the moving image for a predetermined time is completed. Good.

  As shown in FIG. 6, in the displacement measurement process, first, in step S <b> 1, the image information acquisition unit 35 acquires image data (frame image data) of a moving image from the imaging unit 20 and performs necessary image processing and processing. Apply processing. In the next step S2, the displacement information calculation unit 36 calculates displacement data at a plurality of predetermined measurement points for each frame by image analysis based on the image data acquired in step S1, and stores it in the storage unit 34. Remember.

  In the next step S3, the smoothing processing unit 37 uses time series displacement data (large-scale multipoint displacement data) at a plurality of measurement points calculated in step S2, the number of rows as time, and the number of columns as space. Is read from the storage unit 34 as a matrix. The number N of rows and the number M of columns of the read displacement data are calculated. In the case of a moving image, the number of frames in the frame image can be set to N rows. Further, the total number of measurement points can be set to the number M of columns in the space. Thereafter, the process proceeds to step S4.

  In step S4, it is determined whether the number of columns M is 100 or less in order to determine whether to perform smoothing based on the number of columns M and to determine the order for smoothing. If the number M of columns is 100 or less (YES in step S4), the process proceeds to step S17 without performing smoothing.

  On the other hand, if the number of columns M is greater than 100 (NO in step S4), the process proceeds to step S5 in order to set the order for smoothing. In step S5, it is determined whether the number of columns M is 200 or more. If 200 or more (YES in step S5), the process proceeds to step S6, and the smoothing order is set to 20. On the other hand, if the number of columns M is less than 200 (NO in step S5), the process proceeds to step S7, and the order of smoothing is set to 1/10 of the number of columns M. When the order is set, the process proceeds to step S8.

  In step S8, 1 is set to the row number counter n. The row number counter n is a counter for performing smoothing processing on displacement data, which is spatio-temporal data, every time (frame), that is, every n-th row, and represents the number of rows (time) currently being processed.

  Next, proceeding to step S9, 1 is set to the column number counter m. This column number counter is a counter for sequentially smoothing displacement data at each measurement point at the time of the n-th row according to the order, and represents the number of columns (measurement points) currently being processed.

  Thereafter, when the process proceeds to step S10, the smoothing processing unit 37 performs the smoothing process of the displacement data at the time of the n-th row using the moving average filter or the median filter according to the order set in step S6 or S7. .

  Next, the process proceeds to step S11, where it is determined whether the column number counter m = M, that is, whether the smoothing process has been completed using the displacement data at all measurement points in the nth row. If m <M (determination in step S11 is NO), since the smoothing process using all the measurement points has not been completed, the process proceeds to step S12 to increment the column number counter m (m = m + 1). ), Returning to step S10, the displacement data smoothing process is continued.

  When m = M (determination in step S11 is YES) and the smoothing process using the displacement data at all the measurement points in the n-th row is completed, the process proceeds to step S13.

  In order to prove the effect of the moving average filter processing, in FIG. 3, a graph representing the deformed shape by plotting the original displacement data before smoothing processing at a certain point and the displacement data after smoothing processing are plotted. The graph showing the deformed shape is shown. The graph of FIG. 3 uses a model bridge in which one RC girder is supported by a pier instead of the actual bridge 1 as shown in FIG. It is obtained by measuring the displacement with the measuring device 10. A 20th order moving average filter was used for the smoothing process. As can be seen from FIG. 3, compared to the graph of the deformed shape before the smoothing process, in the graph of the deformed shape of the smoothing process, the rigid body translation / rotation component and the bending deformation component at the time point are more intuitive. I can understand.

  Next, in step S13, it is determined whether or not the row number counter n = N, that is, whether or not the smoothing processing of the displacement data of all the rows (time) is completed. When n <N (determination in step S13 is NO), the smoothing process has not been completed for all rows, and the process proceeds to step S14. After counting up the row number counter n in step S14 (n = n + 1), the process returns to step S9 to set the row number counter m to 1 for initialization, and then proceeds to step S10 to proceed to the next nth row. Continue smoothing the displacement data over time.

  On the other hand, when n = N (determination in step S13 is YES) and the displacement data smoothing process at all times is completed, the process proceeds to the three-dimensional image generation process in step S15.

  In step S15, the display image generation unit 38 plots the smoothed displacement data as a curved surface in the three-dimensional space of the time axis, the space axis, and the displacement axis, and generates a three-dimensional image to be displayed on the display unit 31. To do. At this time, the display image generation unit 38 calculates a curved surface based on the displacement data after the smoothing process. In addition, the visibility can be improved by changing the display color according to the magnitude of the displacement and performing gradation. Further, by making the curved surface translucent, it is possible to improve the visibility of the overlapping portions of the graphs. In such a three-dimensional image, an intuitive understanding of displacement can be promoted.

  Thereafter, the process proceeds to step S <b> 16, and the display image generation unit 38 displays the three-dimensional image generated in step S <b> 14 on the display unit 31.

  If it is determined in step S4 that the number M of columns is 100 or less and the process proceeds to step S17 without performing the smoothing process, the display image generation unit 38 acquires the original displacement data before the smoothing process. To generate a three-dimensional image. Also in this case, visibility can be improved by gradation or semi-transparency. Thereafter, the process proceeds to step S16, and the display image generation unit 38 displays the three-dimensional image generated in step S17 on the display unit 31.

  As described above, in this embodiment, even when the number of columns M is 100 or less, a three-dimensional image is generated and displayed. However, the present invention is not limited to this. If step S17 is not provided and the number of columns M is 100 or less, the displacement measurement process may be immediately terminated.

  Thus, the displacement measuring process by the displacement measuring device 10 is completed. By measuring the three-dimensional image generated based on large-scale multipoint displacement data (big data), the measurer can determine the deformation shape of the beam-like structure such as rigid body translation / rotation deformation, bending deformation, and time. It becomes possible to intuitively understand typical vibration properties.

  FIG. 5 shows an example of a three-dimensional image of the displacement waveform generated based on the displacement data after the smoothing process. For reference, FIG. 4 shows an example of a three-dimensional image generated based on the original displacement data before the smoothing process. The three-dimensional images in FIGS. 4 and 5 are also generated based on the displacement data of the model bridge measured by the displacement measuring apparatus 10 of the present embodiment.

  4 and FIG. 5, “Disp” represents displacement, “Frame num.” Represents frame number, that is, time, and “Measurement points” represents measurement point, that is, space. In addition, “Excitation” in the three-dimensional image represents a position and a point of time when shock is applied by a hammer. The same applies to the three-dimensional images shown in FIGS.

  According to the three-dimensional image shown in FIG. 5 based on the displacement data after the smoothing process, the vibration due to the primary bending deformation and the rigid body translation is excited after the impact excitation, the bending deformation is immediately damped, and the rigid body vibration is gradually increased. You can intuitively understand how it decays.

  On the other hand, in the three-dimensional image of FIG. 4 based on the original displacement data before the smoothing process, it can be confirmed that the vibration gradually attenuates after the impact excitation, but the deformation component is captured by noise. I understand that I can't.

  Note that the display direction of the three-dimensional image is not limited to that shown in FIGS. 4 and 5, and three-dimensional images with different display directions can be generated. Alternatively, the measurement person can operate the operation unit 32 and the like to rotate the three-dimensional image in the display unit 31 so that the measurement person can arbitrarily change the display direction of the three-dimensional image. In any case, it is desirable to display the three-dimensional image in a display direction that is easy for the measurer to see according to the deformation state or the like.

  As described above, the displacement measuring apparatus 10, the displacement measuring method, and the program according to the first embodiment can accurately measure the displacement of the measurement target and can intuitively understand the displacement of the measurement target. Further, by utilizing this highly accurate measurement result, it becomes possible to accurately detect damage and evaluate the state of the measurement object. Below, the specific example which measures the displacement of the bridge 1 using the displacement measuring apparatus 10 of this embodiment, and detects (evaluates) a support state using the measurement result is demonstrated.

(Example of detection of bearing status)
The three-point support state will be described with reference to FIG. In the bridge pier 1 shown in FIG. 7, the corners 2a-2d of the RC beam 2 having a rectangular shape in plan view are supported by four supports 4a-4d on the pair of bridge piers 3a, 3b.

  In the case of the RC girder 2 supported by such four-point supports 4a-4d, a three-point support state in which only the support portion of one support 4a-4d is lifted due to the sinking or eccentricity of the piers 3a, 3b. May be. FIG. 7 shows an example in which one pier 3a is inclined due to settlement or eccentricity. In the bridge 1 in this state, an excessive load is applied to the support 4b and the support 4c by the passage of the train T, the load applied to the support 4d is reduced, and the corner 2a of the RC girder 2 is lifted on the support 4a side. The state becomes a three-point support state.

  In this three-point support state, a phenomenon occurs in which the support 4a and the RC girder 2 repeatedly collide as the train T passes. Generally, it is said to be “fluttering” of the bearing 4 and is known as a typical abnormality of the bearing section. If this three-point support state is left unattended, this will result in damage to the bearings and abnormalities. Further, even when the three-point support is used, there is a case where the float cannot be confirmed in appearance, and it is often found that the three-point support state has been obtained after the damage has occurred. In order to suppress damage or the like, it is important to detect an abnormality in the bearing state quickly and accurately.

  In order to verify that the abnormality in the bearing state can be detected promptly and accurately by the displacement measuring apparatus 10 of the present embodiment, a model bridge in a three-point support state and a model bridge in a healthy state without floating Were subjected to shock excitation to measure the displacement. Then, each three-dimensional image was generated based on the displacement data after the smoothing process and displayed on the display unit 31. The displacement measurement procedure is as described above using the flowchart of FIG.

  FIG. 8 shows a three-dimensional image when the displacement of the model bridge in the three-point support state is measured, and FIG. 9 shows a three-dimensional image when the displacement of the model bridge in a healthy state without floating is measured.

  According to the three-dimensional image in FIG. 8, it can be seen that when there is a float in a three-point support state, no bearing reaction force is generated by impact excitation. On the other hand, according to the three-dimensional image in FIG. 9, it can be seen that in a healthy support state without floating, an upper amplitude is generated immediately after impact excitation due to the support reaction force.

  In addition, because of the unbalanced bearing reaction force, the bridge immediately after impact excitation has a rigid body rotation as well as a rigid body rotation component. Is repeated.

  From the results of FIGS. 8 and 9, it can be seen that while one wave vibrates in a healthy support state without floating, two waves vibrate in a three-point support state with floating. Further, in the case of a healthy state with no floating, as shown in FIG. 9, the left and right average bearing displacements are substantially the same, and the duration time of the upper amplitude immediately after the impact excitation is also substantially the same. Since the rigid body rotation component is attenuated immediately after about 2 waves, it is desirable to use the waveform immediately after the vibration.

  As described above, in this embodiment, since the displacement of the measurement target can be measured with high accuracy, the measurement target is healthy by analyzing the measurement result (three-dimensional image, etc.) according to the prominent degree of each vibration component. It can be accurately determined whether or not there is. Further, in the case of an abnormality, it is possible to accurately determine where the abnormality has occurred. In addition, if you measure the displacement of various states in advance using a model bridge, etc., and grasp the characteristics of the waveform in each state in advance, these and the actual measurement object when shocked By comparing the measurement result of the displacement, the state of the measurement object can be evaluated quickly and accurately.

  Moreover, it is known that the local damage of a measuring object appears in the curvature of bending deformation. Therefore, the damage position based on the bending deformation can be identified by measuring the displacement using the displacement measuring apparatus 10 or the like of the present embodiment. Moreover, in this embodiment, since displacement can be accurately measured using big data, it can be applied to verification of a large-scale numerical analysis model of a beam-like structure.

  Next, the operation of this embodiment will be described. The displacement measuring apparatus 10 of the present embodiment includes an image information acquisition unit 35 that acquires a plurality of image data (captured images) of a measurement target that are continuously captured by the imaging unit 20 every predetermined time, and a plurality of image data. Based on the displacement information calculation unit 36 that calculates the displacement data (displacement information) from the reference position of the plurality of measurement points to be measured in time series, and the displacement information of the plurality of measurement points at a predetermined time by the smoothing filter And a smoothing processing unit 37 for smoothing.

  Further, the displacement measuring method of the present embodiment is performed by the displacement measuring apparatus 10 of the present embodiment, and a step of acquiring a plurality of captured images of the measurement target continuously captured every predetermined time by the imaging unit 20; Based on a plurality of captured images, a step of calculating displacement information from a reference position of a plurality of measurement points to be measured in a time series, and smoothing the displacement information of the plurality of measurement points every predetermined time by a smoothing filter And a process.

  In addition, the program of the present embodiment includes a computer that acquires a plurality of captured images of a measurement target that are continuously captured every predetermined time, and a plurality of measurement points of the measurement target based on the plurality of captured images. Is a program for functioning as means for calculating displacement information from the reference position in time series and means for smoothing displacement information of a plurality of measurement points at a predetermined time by a smoothing filter.

  Therefore, in the present embodiment, by using the image captured by the imaging unit 20, a conventional target is not necessary, and displacement data at many measurement points can be acquired. In particular, by using the imaging unit 20 with high image quality and high sampling rate, large-scale multipoint displacement data (so-called big data) can be acquired. Even with this enormous amount of displacement data, the noise of the displacement data that differs at each measurement point can be accurately removed by the smoothing process. Therefore, the displacement of the measurement object can be accurately measured based on the smoothed displacement data. Therefore, the displacement measuring device 10 that can intuitively understand the displacement of the measurement object, such as the deformation shape of the beam-like structure such as the rigid body flattening / rotation and bending deformation, the temporal vibration property, the displacement measuring method, and the like A program can be provided.

  Further, in the present embodiment, the display image generation unit 38 that generates a three-dimensional image representing the displacement of the measurement object in time series and displays it on the display unit 31 based on the smoothed displacement data of the plurality of measurement points. It has a configuration with. This three-dimensional image makes it easier for the measurer to visually understand the displacement data, and allows the displacement of the measurement object to be understood more intuitively.

  Moreover, in this embodiment, the smoothing process part 37 becomes a structure which smoothes displacement data by the order on the basis of the total number of measurement points. Thereby, an appropriate smoothing process according to the total number of measurement points is possible, and the displacement of the measurement object can be understood more intuitively.

  Further, in the present embodiment, the deformation of the beam-like structure (bridge 1) in which the corners 2a-2d of the RC girder 2 having a rectangular shape in plan view are supported by a plurality of supports 4a-4b is measured. The support state detection unit 39 that detects the support state of the RC beam 2 by the support 4a-4b based on the displacement data of the plurality of measurement points smoothed by the conversion processing unit 37 may be used. it can. With this configuration, the support state by the supports 4a-4b can be accurately detected, and the support state can be intuitively understood.

(Second Embodiment)
Next, the displacement measuring apparatus 10 of 2nd Embodiment is demonstrated based on drawing. The displacement measuring apparatus 10 according to the second embodiment is the same as the displacement measuring apparatus according to the first embodiment shown in FIGS. 1 and 2 except that the control unit 33 is provided with a support state detecting unit 39 indicated by a dotted line in FIG. 10 has the same basic configuration. Therefore, in the following, the configuration different from the first embodiment will be mainly described, the same reference numerals are given to the same configuration as the first embodiment, and the detailed description will be omitted.

  In the displacement measuring apparatus 10 according to the second embodiment, an imaging unit 20 and a calculation unit 30 mainly including a display unit 31, an operation unit 32, a control unit 33, and a storage unit 34 are connected by a cable 40. As shown in FIG. 2, the control unit 33 includes an image information acquisition unit 35, a displacement information calculation unit 36, a smoothing processing unit 37, a display image generation unit 38, and a support state detection unit 39. The support state detection unit 39 detects the support state of the RC beam 2 by the support 4 based on the displacement data of the plurality of measurement points smoothed by the smoothing processing unit 37.

  In the said 1st Embodiment, the measurer evaluated the support state based on the measurement result (three-dimensional image) of a displacement. On the other hand, in the displacement measuring apparatus 10 of 2nd Embodiment, the support state detection part 39 is the structure which detects the support state by support automatically.

  In addition, although the support state detection part 39 of this embodiment has detected the support state using the predominance degree of a rigid body rotation component, it is not limited to this, It detects a support state by another method. You can also.

  The procedure for detecting the support state will be described. First, similarly to the first embodiment, the RC girder 2 is impacted and the moving image is captured by the imaging unit 20. And the image information acquisition part 35 acquires the image data of the moving image image | photographed with the imaging part 20, and the displacement information calculation part 36 calculates the displacement data in each measurement point in time series based on this image data. Based on the displacement data, the smoothing processing unit 37 executes a smoothing process.

  Next, the support state detection unit 39 extracts the deformation at the maximum amplitude recording time immediately after the impact excitation based on the large-scale multipoint displacement data after the smoothing process. A linear function (slope and intercept) is calculated for the deformed shape at the time of recording the maximum amplitude. The support state detection unit 39 determines that there is a float in the smaller amplitude when there is a certain difference in the amplitudes at the two fulcrum portions of the calculated linear function. As an example of the difference in amplitude at both fulcrum portions used for the determination of floating, there is, for example, twice.

  The display image generation unit 38 generates a three-dimensional image based on the large-scale multipoint displacement data, and superimposes a line segment representing a linear function on the three-dimensional image, and displays it on the display unit 31. . At this time, you may display with a three-dimensional image on the character string display parts 31, such as "there is a float (three-point support state)" and "a healthy state". The measurer can intuitively understand not only the deformed shape and the vibration shape of the measurement target but also whether the support state is sound by merely viewing the three-dimensional image displayed on the display unit 31. it can.

  FIG. 10 shows a three-dimensional image when the displacement of the model bridge in the three-point support state is measured, and FIG. 11 shows a three-dimensional image when the displacement of the model bridge in the healthy state without floating is measured.

  According to the three-dimensional image in FIG. 10, when the support portion is lifted, the rigid body rotation component is dominant together with the rigid body translation of the bridge 1 immediately after the impact excitation. As a result, the rigid body rotation component of the bridge 1 becomes large at the time when the maximum displacement is recorded immediately after impact excitation. By obtaining a linear function of a deformed shape as in the present embodiment, this tendency can be clarified and the influence of errors due to noise can be reduced.

  According to the three-dimensional image in FIG. 11, when there is no floating, the rotational component is hardly excited, so the amplitude values of both fulcrum portions at the time of recording the maximum displacement are approximately the same value (0.75 to 1 .2) It is understood that it becomes about.

  In the present embodiment, whether or not there is a float is determined based on the calculated linear function, but is not limited thereto. The support state detection unit 39 performs the calculation of the linear function without performing the determination, and the measurer himself / herself sees the three-dimensional image on which the line segment of the linear function is superimposed. It may be determined whether or not there is a float.

  As described above, since the displacement measuring apparatus 10, the displacement measuring method, and the program according to the second embodiment can measure the displacement of the measurement object with high accuracy as in the first embodiment, the support is based on the measurement result. The state and the like can be detected with high accuracy. Moreover, since the support state is automatically detected by the displacement measuring device 10, the measurer can intuitively understand the support state by visually checking the detection result.

  Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to these embodiments, and design changes that do not depart from the gist of the present invention are not limited thereto. include.

  For example, in each of the above-described embodiments, the displacement measuring apparatus 10 includes the imaging unit 20, and the captured image captured by the imaging unit 20 is sequentially input to the arithmetic unit 30, but the configuration is limited to this configuration. It is not a thing. The calculation unit 30 only needs to be able to acquire the captured image. For example, the captured image captured by the imaging unit 20 is recorded in the storage unit of the imaging unit 20 and data of all captured images is transferred to the calculation unit 30. You can also. In addition, it is also possible to adopt a configuration in which captured images taken on site are downloaded via a communication line such as the Internet or installed from a USB memory or an SD memory card.

  In addition, the calculation unit 30 is not limited to a PC, and a portable terminal such as a tablet terminal or a smartphone can be used as long as it has an ability to process large-scale multipoint displacement data.

  Further, in each of the above embodiments, as shown in FIG. 7, the RC girder 2 supported by the four bearings 4 is the detection target of the support state, but the detection target is limited to the example of FIG. is not. For example, even in an RC girder 2 supported by five or more bearings 4, the bearing state can be detected with high accuracy by the displacement measuring device 10, the displacement measuring method, and the program of each of the above embodiments.

1 Bridge (measurement target)
2 RC digit (measurement target)
2a-2d Corner 4a-4d Support 10 Displacement measuring device 20 Imaging unit 31 Display unit 33 Control unit 35 Image information acquisition unit 36 Displacement information calculation unit 37 Smoothing processing unit 38 Display image generation unit 39 Support state detection unit

Claims (6)

A displacement measuring device that measures a displacement when the measuring object is vibrated based on a captured image of the measuring object,
An image information acquisition unit for acquiring a plurality of captured images of the measurement object continuously photographed every predetermined time;
Based on the plurality of captured images, a displacement information calculation unit that calculates, in a time series, displacement information from a reference position of the plurality of measurement points of the measurement target;
A displacement measurement apparatus comprising: a smoothing processing unit that smoothes the displacement information of the plurality of measurement points at each predetermined time with a smoothing filter.   A display image generation unit configured to generate a three-dimensional image representing the displacement of the measurement object in time series and display the display unit on the display unit based on the displacement information of the plurality of measurement points that have been smoothed; The displacement measuring apparatus according to claim 1.   The displacement measuring apparatus according to claim 1, wherein the smoothing processing unit smoothes the displacement information by an order based on the total number of the measurement points. The measurement object is a beam-like structure in which corners of a rectangular beam in plan view are supported by a plurality of supports,
The support state detection unit that detects a support state of the beam by the support based on the displacement information of the plurality of measurement points smoothed by the smoothing processing unit. The displacement measuring apparatus as described in any one of 1-3. It is the displacement measuring method performed with the displacement measuring apparatus as described in any one of Claims 1-4,
Acquiring a plurality of captured images of a measurement object continuously photographed every predetermined time;
Based on the plurality of captured images, calculating displacement information from a reference position of the plurality of measurement points of the measurement object in time series;
Smoothing the displacement information of the plurality of measurement points at each predetermined time with a smoothing filter. Computer
Means for acquiring a plurality of captured images of the measurement object continuously photographed every predetermined time;
Means for calculating displacement information from a reference position of a plurality of measurement points of the measurement object in time series based on the plurality of captured images;
The program for functioning as a means to smooth | blunt the said displacement information of these measurement points for every said predetermined time with a smoothing filter.