Vibration measurement device, vibration measurement method, and program

Abstract

To provide a vibration measurement device, a vibration measurement method, and a program using compression sensing and image analysis.SOLUTION: A vibration measurement device 1 includes: a light receiving unit 10 for exposing a light receiving element a plurality of times to acquire an optical physical quantity related to a vibrating object for each exposure; a light source 20 for emitting light only once at random timing within an exposure time for each exposure; and a control device 40. The control device 40 includes: an analysis processing unit 402 for calculating a physical quantity related to vibration of an object based on an optical physical quantity; and a compression sensing processing unit 403 for reconfiguring vibration behavior of the object by executing compression sensing based on timing of light emission and the physical quantity related to vibration of the object.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a vibration measurement device, a vibration measurement method, and a program, and particularly to a vibration measurement method using compressive sensing and image analysis.

Background Art

[0002] The vibration behavior of a structure is important information for examining the state and characteristics of the structure. Therefore, measurements are performed in a wide range of fields and situations from the design and development of structures to maintenance management and the like.

[0003] For measuring vibration behavior, acceleration sensors directly attached to the surface of a structure have generally been used. However, acceleration sensors have limitations in the attachment locations and can only obtain local information at the attached locations, so there is a problem that it is difficult to grasp the behavior of the entire structure. In addition, when attaching multiple sensors, there are cost and operation issues such as increased costs for sensors and loggers and difficulties in power management. Also, when the structure to be measured is lightweight, there is a problem that the vibration behavior of the structure changes by attaching the sensor.

[0004] On the other hand, in recent years, techniques for measuring the deformation of a structure by analyzing an image taken with a camera have been proposed (see Patent Document 1 and Non-Patent Document 1). Deformation measurement using an image can analyze a wide area in the image in a planar manner, so intuitive understanding and mechanical interpretation are easy. Also, since it is non-contact, it can be measured without affecting the vibration of the structure itself. Furthermore, since the spatial information (mode) of vibration can be captured, an abnormal state of the structure can be detected based on changes in the mode.

Prior Art Documents

Non-Patent Documents

[0005]

Patent Document 1

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0006] By the way, in order to measure vibration, it is said that sampling must be performed at a frequency twice the vibration frequency (Nyquist frequency) (sampling theorem). Therefore, when applying the conventional image-based deformation measurement technology to the measurement of high-speed vibration behavior, a high-speed camera is required. However, the adoption of a high-speed camera has problems in that the cost is extremely high, and a long calculation time and a large amount of recording storage are required for analyzing a huge amount of image data. In addition, high-speed cameras often have a low resolution, and may be able to measure only a narrow range or may not be able to capture small vibrations.

[0007] The present invention has been made to solve these problems, and an object thereof is to provide a vibration measuring device, a vibration measuring method, and a program using compressive sensing and image analysis.

Means for Solving the Problems

[0008] According to one embodiment, a vibration measuring device includes a light receiving unit that exposes a light receiving element a plurality of times and acquires an optical physical quantity related to an object to be vibrated each time of the exposure, a light source that emits light only once at a random timing within the exposure time each time of the exposure, and a control device. The control device includes an analysis processing unit that calculates a physical quantity related to the vibration of the object based on the optical physical quantity, and a compressive sensing processing unit that reconstructs the vibration behavior of the object by performing compressive sensing based on the timing of the light emission and the physical quantity related to the vibration of the object. According to one embodiment, a vibration measuring device includes a light receiving unit that repeatedly performs a process of exposing a light receiving element only once at a random timing within a predetermined time and acquiring an optical physical quantity related to an object to be vibrated, and a control device. The control device includes an analysis processing unit that calculates a physical quantity related to the vibration of the object based on the optical physical quantity, and a compressive sensing processing unit that reconstructs the vibration behavior of the object by performing compressive sensing based on the timing of the exposure and the physical quantity related to the vibration of the object. According to one embodiment, a vibration measuring method includes a light receiving step of exposing a light receiving element a plurality of times and acquiring an optical physical quantity related to an object to be vibrated each time of the exposure, a light emitting step of emitting light from a light source only once at a random timing within the exposure time each time of the exposure, an analysis processing step of calculating a physical quantity related to the vibration of the object based on the optical physical quantity, and a compressive sensing processing step of reconstructing the vibration behavior of the object by performing compressive sensing based on the timing of the light emission and the physical quantity related to the vibration of the object. According to one embodiment, the vibration measurement method includes a light emission step of emitting light from a light source a plurality of times, a light reception step of, for each light emission, exposing a light receiving element only once at a random timing within the light emission time to obtain an optical physical quantity related to an object to be vibrated, an analysis processing step of calculating a physical quantity related to the vibration of the object based on the optical physical quantity, and a compressive sensing processing step of reconstructing the vibration behavior of the object by performing compressive sensing based on the exposure timing and the physical quantity related to the vibration of the object. According to one embodiment, the program causes a computer to execute a step of generating a first control signal for exposing a light receiving element a plurality of times and obtaining an optical physical quantity related to an object to be vibrated for each exposure, a step of generating a second control signal for emitting light from a light source only once at a random timing within the exposure time for each exposure, an analysis processing step of calculating a physical quantity related to the vibration of the object based on the optical physical quantity, and a compressive sensing processing step of reconstructing the vibration behavior of the object by performing compressive sensing based on the light emission timing and the physical quantity related to the vibration of the object. According to one embodiment, the program causes a computer to execute a step of generating a first control signal for emitting light from a light source a plurality of times, a step of generating a second control signal for exposing a light receiving element only once at a random timing within the light emission time for each light emission to obtain an optical physical quantity related to an object to be vibrated, an analysis processing step of calculating a physical quantity related to the vibration of the object based on the optical physical quantity, and a compressive sensing processing step of reconstructing the vibration behavior of the object by performing compressive sensing based on the exposure timing and the physical quantity related to the vibration of the object.

Advantages of the Invention

[0009] The present invention can provide a vibration measurement apparatus, a vibration measurement method, and a program using compressive sensing and image analysis.

Brief Description of the Drawings

[0010]

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Mode for Carrying Out the Invention

[0011] <Overview> First, the features of a data science technique called compressive sensing adopted by the present invention will be briefly explained. Compressive sensing is a framework for reconstructing a high-dimensional target signal from a small number of observations (see Non-Patent Document 2). In the present invention, attention is paid to compressive sensing, which is widely used in speeding up MRI, a medical device, and astronomy, and by applying this to vibration measurement by image analysis, the above-mentioned problems are solved.

[0012] According to compressive sensing, a wide range of detailed information can be estimated (reconstructed) from a very small amount of observation data. Compressive sensing can theoretically be applied in both the spatial and temporal directions, but there are many application examples aimed at reconstructing spatial information. This is presumably because, in order to achieve high performance in the temporal direction, expensive equipment such as a high-speed camera is required as described above.

[0013] This is due to the fact that the application of compressive sensing requires a measurement method called random sampling. Random sampling literally means measuring irregularly, and when reconstructing in the time direction, it is necessary to measure at irregular timings. At this time, the fineness of the information that can be reconstructed by compressive sensing (the height of the vibration frequency that can be reconstructed) is determined by the shortness of the adjustment time of this time interval (time resolution), and vibrations with a time shorter than this time resolution cannot be reconstructed. The upper limit of the measurement interval (shooting speed) that can be set in general cameras and measuring instruments is insufficient to reconstruct high-speed phenomena using compressive sensing, and it was considered essential to use very expensive equipment such as high-speed cameras.

[0014] In one embodiment of the present invention, by combining a strobe light source with a short emission time, a signal generator that controls its emission timing, and a control program, even a very high-speed vibration phenomenon that is about several hundred times the shooting speed of a camera can be reconstructed using very inexpensive equipment.

[0015] Furthermore, in one embodiment of the present invention, by applying compressive sensing also in the spatial direction using the information reconstructed in the time direction, it is made possible to reconstruct the spatial vibration behavior (vibration mode) from a very small number of measurement points.

[0016] In the verification experiment conducted by the applicants, using a camera with a general shooting speed of 10 frames per second, the frequency of the phenomenon vibrating at 3210 times per second (the mode of vibration at a certain measurement point) and the spatial vibration shape (the mode of variation of the shape of the structure) were successfully reconstructed. Also, even when a waveform synthesized from 10 vibrations with different amplitudes of 90 to 160 times per second was input to the structure instead of a single frequency, all the frequencies and the spatial vibration shapes were successfully decomposed and reconstructed individually.

[0017] A specific embodiment to which the present invention is applied will be described in detail with reference to the drawings. <Embodiment 1> FIG. 1 is a block diagram showing the hardware configuration of the vibration measurement device 1 according to Embodiment 1 of the present invention. The vibration measurement device 1 includes a light receiving unit 10, a light source 20, a signal generation device 30, and a control device 40.

[0018] The light receiving unit 10 is typically a camera that captures visible light emitted from an object to form a visible image. Alternatively, it may be an infrared camera or an ultraviolet camera that is sensitive to non-visible light, or a laser displacement meter that measures the shape and displacement of an object. That is, the light receiving unit 10 is a device that can measure optical physical quantities related to an object by optical means (light receiving elements). Hereinafter, for the sake of simplicity of explanation, the measurement process of physical quantities by the light receiving unit 10 is referred to as "imaging", and the measured data is referred to as an "image".

[0019] The light receiving unit 10 performs imaging at the timing when a control signal is input from the outside. That is, exposure is started at the input timing of the control signal, exposure is ended when a predetermined exposure time has elapsed, and processes such as transfer and storage of imaging data are performed. Alternatively, the light receiving unit 10 starts imaging at the timing when a control signal is input from the outside and repeatedly performs imaging at a predetermined interval. That is, exposure is started at the input timing of the control signal, exposure is ended when a predetermined exposure time has elapsed, and processes such as transfer and storage of imaging data are performed. Then, when a predetermined time has elapsed since the previous exposure, exposure, a series of processes such as transfer and storage of imaging data are performed again. The control signal may be output by a controller such as a release, or may be an electrical signal such as a pulse train output by the signal generation device 30. At this time, the imaging time of the image can be specified by recording the signal output time on the output side of the control signal.

[0020] The light source 20 is typically a strobe. Alternatively, it may be a laser oscillator or the like. That is, the light source 20 is a device that generates light necessary for the light receiving unit 10 to perform imaging.

[0021] The light source 20 emits light at a specified timing according to a control signal input from the outside. That is, light emission starts at the input timing of the control signal and ends when a predetermined light emission time has elapsed. The control signal is an electrical signal such as a pulse train output by, for example, the signal generation device 30. At this time, by recording the signal output time on the output side of the control signal, the light emission time of the light source 20 can be specified. In the first embodiment, the light source 20 desirably has a short light emission time, a short light emission interval (the preparation time required from light emission to the next light emission), and a large light amount. The shorter the light emission time and light emission interval of the light source 20, the higher the vibration frequency phenomenon that the vibration measuring device 1 can reconstruct.

[0022] The signal generation device 30 is a device that generates and outputs an electrical control signal at a preset timing in order to control the imaging timing of the light receiving unit 10 and the light emission timing of the light source 20. The higher the time resolution of this process, that is, the finer the adjustment of the output timing of the control signal, the higher the vibration frequency phenomenon that the vibration measuring device 1 can reconstruct. The time resolution is determined depending on the internal clock of the signal generation device 30 and the like. The signal generation device 30 can be configured using, for example, a dedicated device such as a function generator or a general-purpose device such as a microcomputer or an FPGA (Field Programmable Gate Array). The signal waveform output by the signal generation device 30 can be changed according to the specifications of the light receiving unit 10 and the light source 20, but generally a pulse train is used.

[0023] The control device 40 is typically a personal computer or a microcomputer, and realizes a predetermined functional element, that is, a processing unit, by reading and executing a program stored in the memory by the processor. FIG. 2 is a block diagram showing the functional configuration of the control device 40. The control device 40 includes a signal generation processing unit 401, an analysis processing unit 402, and a compressive sensing processing unit 403.

[0024] The signal generation processing unit 401 performs a process of setting the output timing of a control signal for the signal generation device 30. The output timing of the control signal is calculated according to the exposure time (shutter speed) of the light receiving unit 10, the shooting speed (the number of shots per unit time, which is determined by the exposure time + data transfer time, etc.), the minimum light emission interval of the light source 20, the light emission time, etc. The exposure time of the light receiving unit 10 can be set as long as possible within a settable range, for example. The shooting timing of the light receiving unit 10 may be at regular intervals or irregularly. In the present embodiment, the light emission timing of the light source 20 is set to be once within each exposure time of the light receiving unit 10. Also, the light emission timing is determined according to an arbitrary probability distribution such as a uniform random number or a normal distribution random number according to the time resolution of the signal generation device 30. That is, the light source 20 is set to emit light only once at a random timing during each exposure of the light receiving unit 10 and not to emit light during the data transfer time after the exposure. The signal generation processing unit 401 can store the set value of the output timing of the control signal calculated here in a storage area (not shown). The set value of the output timing of the control signal can be repeatedly used many times, and there is no need to recalculate it for each measurement as long as it is under the same light receiving unit 10, light source 20, and shooting conditions. The set value of the output timing of the control signal calculated here is also used in the compressive sensing processing unit 403 described later.

[0025] The analysis processing unit 402 acquires randomly sampled image data, that is, a series of image data captured by the light receiving unit 10 under the control of the vibration measurement device 1. Then, from each of the acquired images, local physical quantities related to the vibration of the object, such as displacement and strain, are calculated. Known techniques such as the digital image correlation method (DIC) and the sampling moiré method can be used for this analysis.

[0026] The compressive sensing processing unit 403 executes compressive sensing using the time-series data of the physical quantity calculated by the analysis processing unit 402 and the set value of the output timing of the control signal created by the signal generation processing unit 401.

[0027] FIG. 3 is a diagram for explaining a specific method for applying compressive sensing to vibration measurement.

[0028] Compressive sensing is a method for estimating an unknown vector x based on linear observation. Even if the signal x cannot be directly observed, if the product of the signal x and the observation matrix A is observable (linear observation), x can be estimated (reconstruction) using the observation result y and the observation matrix A. Note that the specific procedure for reconstruction is omitted in this article (see Non-Patent Document 2).

[0029] In this embodiment, the unknown vector x is a waveform representing the vibration of the object (changes in physical quantities such as displacement and strain over time).

[0030] As the observation matrix A, a matrix representing the timing of observation, that is, the timing of photographing the object, can be used. For example, assuming time slots obtained by dividing the exposure time by the time resolution, a bit string can be generated in which 1 is set for the time slots when the light source 20 emits light and 0 is set for the non-emitting time slots, and this can be used as the elements of the matrix. As a specific example, if the exposure time is 0.6 seconds, the time resolution is 0.1 second (the emission timing of the light source 20 can be controlled at 0.1-second intervals), and the emission timing is 0.4 seconds after the start of exposure, the bit string will be 000010. When photographing is performed M times, M bit strings can be generated. By arranging these M bit strings over M rows as shown in FIG. 3, the observation matrix A can be created.

[0031] As the observation result y, local physical quantities such as displacement and strain calculated by the analysis processing unit 402 based on the photographed image can be used. When photographing is performed M times, the observation result y can be created by arranging M physical quantities over M rows as shown in FIG. 3.

[0032] Note that, as shown in Fig. 4, when performing reconstruction by applying compressive sensing, it is necessary to set a basis, that is, a reference element that constitutes vibration (see Non-Patent Document 2). As the basis, for example, a basis generally used in signal decomposition such as a discrete Fourier basis, a continuous wavelet basis, or a discrete wavelet basis can be used.

[0033] Next, a method for measuring the vibration of a structure using the vibration measuring device 1 will be described with reference to the flowchart of Fig. 5.

[0034] S101: Install a pattern for image analysis on the surface of the object to be measured. For example, apply a pattern to the surface of the object or attach a sticker or the like. The shape of the pattern is arbitrary, and for example, a round shape, a geometric pattern such as an AR marker, a random pattern, a regular or irregular lattice pattern, etc. can be used. Natural patterns or dirt formed on the object surface may also be used as the pattern.

[0035] Note that when using a pattern using a retroreflective material, the influence of ambient light (such as a lighting lamp) can be suppressed, and stable measurement becomes possible. A retroreflective material is a material that reflects light from a light source along substantially the same optical path as the incident light. By installing the light source 20 near the light receiving unit 10, the influence of ambient light other than the light source 20 during shooting by the light receiving unit 10 can be suppressed, and stable measurement can be performed.

[0036] S102: Install the light receiving unit 10 so that the entire measurement range is within the image, and adjust the position and light amount of the light source and the aperture of the lens so that the image analysis pattern appears only at the timing when the light source 20 emits light.

[0037] S103: The signal generation processing unit 401 of the control device 40 calculates a set value for the output timing of the control signal and sets it in the signal generation device 30. That is, the set value is written into a storage area (not shown) of the signal generation device 30.

[0038] Note that the signal generation processing unit 401 may calculate the set value of the output timing of the control signal each time. However, if there is an experience of performing measurement under the same conditions in the past, the set value calculated and stored in the past may be reused.

[0039] S104: Connect the signal generation device 30 to the external control terminal of the light receiving unit 10 and the external control terminal of the light source 20. The signal generation device 30 outputs a control signal to the light receiving unit 10 and the light source 20 according to the set value of the output timing of the control signal. Thereby, the light receiving unit 10 and the light source 20 record the state of the object vibrating at the timing calculated in advance by the signal generation processing unit 401.

[0040] S105: The analysis processing unit 402 analyzes the image acquired by the light receiving unit 10 and acquires time series data (random sampling data) of physical quantities.

[0041] S106: The compressive sensing processing unit 403 obtains a reconstruction result in which the spatial mode and frequency of vibrations at a frequency much higher than the imaging interval of the light receiving unit 10 are decomposed according to the random sampling data of the physical quantity obtained in S105 and the set value of the output timing of the control signal generated by the signal generation processing unit 401.

[0042] <Embodiment 2> In Embodiment 1, during the exposure of the light receiving unit 10, the light source 20 emits light only once at random timing. On the other hand, in Embodiment 2, it is characterized in that during the light emission of the light source 20, the light receiving unit 10 is exposed only once at random timing. Hereinafter, the vibration measurement device 1 according to Embodiment 2 will be described centering on the differences from Embodiment 1. Regarding the configuration and operation common to Embodiment 1, the description will be omitted as appropriate.

[0043] The hardware configuration of the vibration measurement device 1 according to Embodiment 2 is as shown in FIG. 1.

[0044] In addition, in Embodiment 2, the light receiving unit 10 preferably has a shorter exposure time (shutter speed), a higher shooting speed (the number of shots per unit time, which is determined by the exposure time + data transfer time, etc.), and a higher sensitivity. The shorter the exposure time of the light receiving unit 10 and the higher the shooting speed, the more capable the vibration measuring device 1 is of reconstructing a phenomenon with a high vibration frequency.

[0045] In Embodiment 2, the light emission time of the light source 20 can be set as long as possible within a settable range, for example. The light emission timing of the light source 20 may be at regular intervals or irregularly.

[0046] The exposure timing of the light receiving unit 10 is once within each light emission time of the light source. Also, the exposure timing is determined according to an arbitrary probability distribution such as a uniform random number or a normal distribution random number according to the time resolution of the signal generation device 30. That is, the light receiving unit 10 exposes only once at a random timing during each light emission of the light source 20.

[0047] Note that the time gap between each light emission of the light source 20 may be 0 or more. When the time gap exceeds 0, the light source 20 emits light intermittently. That is, it blinks. For example, when each light emission time is 0.6 seconds and the time gap between each light emission is 0.1 seconds, the light source 20 blinks by alternately repeating light emission (0.6 seconds) and non-light emission (0.1 seconds). On the other hand, when the time gap is 0, the light source 20 becomes continuous light, and for example, sunlight can be used as the light source 20. For example, when each light emission time is 0.6 seconds and the time gap between each light emission is 0, the light source 20 is objectively continuous light, but the vibration measuring device 1 performs processing assuming that the light source 20 repeats the 0.6-second light emission with a time gap of 0.

[0048] FIG. 6 is a diagram for explaining a specific method for applying compressive sensing to vibration measurement in Embodiment 2. Also in this embodiment, as the observation matrix A, a matrix representing the timing of observation, that is, the timing of photographing the object, can be used. For example, assuming time slots obtained by dividing the emission time by the time resolution, a bit string can be generated in which 1 is set for the time slots during which the light receiving unit 10 is exposed and 0 is set for the non-exposed time slots, and this can be used as the elements of the matrix. For a specific example, if the emission time is 0.6 seconds, the time resolution is 0.1 seconds (the exposure timing of the light receiving unit 10 can be controlled at 0.1-second intervals), and the exposure timing is 0.4 seconds after the start of emission, the bit string will be 000010. When photographing is performed M times, M bit strings can be generated. By arranging these M bit strings over M rows as shown in FIG. 3, the observation matrix A can be created. The unknown vector x and the observation result y can be created in the same manner as in Embodiment 1.

[0049] The method for measuring the vibration of a structure using the vibration measuring device 1 according to Embodiment 2 is as shown in FIG. 5.

[0050] <Verification experiment> The applicant conducted a vibration measurement experiment using the vibration measuring device 1 having the configuration of Embodiment 1 of the present invention. The content and results are shown in FIG. 7 and below.

[0051] Content: Using a shaking table, a combined vibration of 170 Hz and 1130 Hz was input to the center of a flat plate made of an aluminum alloy. The flat plate in this state was photographed using the light receiving unit 10 having a photographing speed of 10 Hz (10 fps, that is, 10 frames per second). During the exposure of the light receiving unit 10, the light source 20 was made to emit light once at a random timing.

[0052] Result: The compressive sensing processing unit 403 decomposed the combined vibration and extracted the modes of 170 Hz and 1130 Hz. This corresponds to 226 times the Nyquist frequency. This verified that the vibration measurement device 1 can decompose waveforms above the Nyquist frequency into modes. Also, the waveforms of the 170 Hz and 1130 Hz modes decomposed at this time were almost identical to the waveforms obtained by finite element method analysis (FEM). From this, the accuracy of the measurement results by the vibration measurement device 1 was verified.

[0053] In other experiments, a 10 Hz camera was used to identify a mode of 3210 Hz (642 times the Nyquist frequency), and decomposition of the 10 Hz frequency was possible. Also, it was confirmed that it is possible to handle steady, random, and decaying structural vibrations.

[0054] As described above, the embodiments of the present invention have been explained. However, the present invention is not limited to the above embodiments and can be appropriately changed without departing from the gist. Within the scope of the present invention, deformation of any component of the embodiment or omission of any component of the embodiment is possible.

[0055] Also, the information processing of the present invention may be realized by hardware or may be realized by a CPU executing a computer program. The computer program can be supplied to the computer by various types of non-transitory computer readable media or transitory computer readable media.

Explanation of Signs

[0056] 1 Vibration measurement device 10 Light receiving unit 20 Light source 30 Signal generation device 40 Control device 401 Signal generation processing unit 402 Analysis processing unit 403 Compressive Sensing Processing Unit

Claims

1. a light-receiving unit that exposes a light-receiving element multiple times and acquires an optical physical quantity related to an object to be vibrated each time of the exposure; a light source that emits light only once at a random timing within the exposure time each time of the exposure; a control device, and the control device includes an analysis processing unit that calculates a physical quantity related to the vibration of the object based on the optical physical quantity; a compressive sensing processing unit that reconstructs the vibration behavior of the object by performing compressive sensing based on the timing of the light emission and the physical quantity related to the vibration of the object, a vibration measurement device.

2. a light-receiving unit that repeats a process of exposing a light-receiving element only once at a random timing within a predetermined time multiple times and acquiring an optical physical quantity related to an object to be vibrated; a control device, and the control device includes an analysis processing unit that calculates a physical quantity related to the vibration of the object based on the optical physical quantity; a compressive sensing processing unit that reconstructs the vibration behavior of the object by performing compressive sensing based on the timing of the exposure and the physical quantity related to the vibration of the object, a vibration measurement device.

3. a light-receiving step of exposing a light-receiving element multiple times and acquiring an optical physical quantity related to an object to be vibrated each time of the exposure; a light-emitting step of emitting a light source only once at a random timing within the exposure time each time of the exposure; an analysis processing step of calculating a physical quantity related to the vibration of the object based on the optical physical quantity; a compressive sensing processing step of reconstructing the vibration behavior of the object by performing compressive sensing based on the timing of the light emission and the physical quantity related to the vibration of the object, a vibration measurement method.

4. a light-emitting step of emitting a light source multiple times; a light-receiving step of exposing a light-receiving element only once at a random timing within the light-emission time each time of the light emission and acquiring an optical physical quantity related to an object to be vibrated; an analysis processing step of calculating a physical quantity related to the vibration of the object based on the optical physical quantity; a compressive sensing processing step of reconstructing the vibration behavior of the object by performing compressive sensing based on the timing of the exposure and the physical quantity related to the vibration of the object, a vibration measurement method.

5. On a computer a step of exposing a light-receiving element multiple times and generating a first control signal for obtaining an optical physical quantity related to an object to vibrate for each exposure; a step of generating a second control signal for causing a light source to emit light only once at a random timing within the exposure time for each exposure; an analysis processing step of calculating a physical quantity related to the vibration of the object based on the optical physical quantity; a program for causing a compressive sensing processing step of reconstructing the vibration behavior of the object by performing compressive sensing based on the timing of the light emission and the physical quantity related to the vibration of the object.

6. A program for causing a computer to: generate a first control signal for causing a light source to emit light multiple times; generate a second control signal for exposing a light-receiving element only once at a random timing within the light emission time for each light emission and obtaining an optical physical quantity related to an object to vibrate; perform an analysis processing step of calculating a physical quantity related to the vibration of the object based on the optical physical quantity; perform a compressive sensing processing step of reconstructing the vibration behavior of the object by performing compressive sensing based on the timing of the exposure and the physical quantity related to the vibration of the object.

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