Vibration measurement device, vibration measurement method, and program

Abstract

The invention provides a vibration measurement device, a vibration measurement method, and a program using compression sensing and image analysis. A vibration measurement device (1) is provided with: a light-receiving unit (10) that exposes a light-receiving element a plurality of times and acquires an optical physical quantity relating to an object to be vibrated during each exposure; a light source (20) that emits light only once at a random timing within the exposure time for each exposure; and a control device (40) provided with: an analysis processing unit (402) that calculates a physical quantity relating to the vibration of the object on the basis of the optical physical quantity; and a compressive sensing processing unit 403 that reconstructs a vibration operation of the object by performing compressive sensing on the basis of the timing of light emission and a physical quantity pertaining to vibration of the object.

Description

Technical Field

[0001] The present invention relates to a vibration measuring device, a vibration measuring method and a program, and more particularly to a vibration measuring technique using compressed sensing and image analysis. Background Art

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

[0003] In the measurement of vibration motion, an acceleration sensor directly attached to the surface of a structure is generally used. However, there are the following problems: the acceleration sensor is restricted in the attachment position, and can only obtain local information of the attachment position, so it is difficult to grasp the overall movement of the structure. In addition, there are price and operational problems such as increased cost of sensors and recorders, difficulty in power management, etc. when multiple sensors are attached. In addition, there is also the problem that the vibration motion of the structure changes due to the attachment of sensors when the structure of the measurement object is lightweight.

[0004] On the other hand, in recent years, a technology for measuring the deformation of a structure by analyzing an image taken with a camera has been proposed (see Patent Document 1 and Non-Patent Document 1). Image-based deformation measurement can perform surface analysis on a wide range of areas in an image, so it is easy to intuitively understand and explain mechanically. In addition, since it is non-contact, it can be measured without affecting the vibration of the structure itself. Furthermore, it is possible to capture the spatial information (pattern) of the vibration, so it is possible to detect abnormal conditions of the structure based on changes in the pattern.

[0005] Prior art literature

[0006] Non-patent literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2020-201146

[0008] Non-patent document 1: “Data Assimilation of Elastic-Plastic Finite Element Analysis Using Ensemble Kalman Filters”, Satoshi Nakano and others, Proceedings of the 31st Conference on Computational Mechanics (CMD2018), No. 18-8, The Japan Society of Mechanical Engineers, November 23, 2018

[0009] Non-patent document 2: Kazufumi Mimura, "Compressed Sensing - Reconstruction of Sparse Information and Its Algorithm -", [online], July 2012, [retrieved on September 1, 2021], Internet (https: / / www.kurims.kyoto-u.ac.jp / kyodo / kokyuroku / contents / pdf / 1803-03.pdf)

[0010] Non-Patent Document 3: “Coded Strobing Photography: Compressive Sensing of High-Speed ​​Periodic Videos.”, Veeraraghavan et al., IEEE Transactions on Pattern Analysis and Machine Intelligence, April 8, 2010, Volume 33, Issue 4, pp. 671-686 Summary of the invention

[0011] Problems to be solved by the invention

[0012] However, in order to measure vibration, sampling must be performed at a frequency (Nyquist frequency) twice the number of vibrations (sampling theorem). Therefore, when the previous image-based deformation measurement technology is applied to the measurement of high-speed vibration movements, a high-speed camera is required. However, there are problems in the following aspects: the cost of using a high-speed camera is very high, and a long calculation time and a large amount of record storage are required for analyzing a large amount of image data. In addition, there are sometimes situations where the resolution of a high-speed camera is often suppressed to a low level, and only a small range can be measured or small vibrations cannot be captured.

[0013] The present invention has been made to solve these problems, and an object of the present invention is to provide a vibration measurement device, a vibration measurement method, and a program using compression sensing and image analysis.

[0014] Means used to solve problems

[0015] According to one embodiment, a vibration measuring device includes: a light receiving unit that exposes a light receiving element multiple times and obtains an optical physical quantity related to a vibrating object each time the exposure occurs; a light source that emits light only once at a random timing within the exposure time each time the exposure occurs; and a control device, the control device including: an analysis processing unit that calculates a physical quantity related to the vibration of the object based on the optical physical quantity; and a compression sensing processing unit that performs compression sensing based on the timing of the light emission and the physical quantity related to the vibration of the object, thereby reconstructing the vibration movement of the object.

[0016] According to one embodiment, a vibration measuring device includes: a light receiving unit, which exposes a light receiving element only once at a random timing within a predetermined time, and repeats the step of obtaining an optical physical quantity related to a vibrating object multiple times; and a control device, the control device including: an analysis processing unit, which calculates a physical quantity related to the vibration of the object based on the optical physical quantity; and a compression sensing processing unit, which performs compression sensing based on the exposure timing and the physical quantity related to the vibration of the object, thereby reconstructing the vibration movement of the object.

[0017] According to one embodiment, a vibration measurement method includes: a light receiving step, in which a light receiving element is exposed multiple times, and an optical physical quantity related to the vibrating object is obtained each time the exposure occurs; a light emitting step, in which a light source is emitted only once at a random timing within the exposure time each time the exposure occurs; an analysis processing step, in which a physical quantity related to the vibration of the object is calculated based on the optical physical quantity; and a compression sensing processing step, in which compression sensing is performed based on the timing of the light emission and the physical quantity related to the vibration of the object, thereby reconstructing the vibration movement of the object.

[0018] According to one embodiment, a vibration measurement method includes: a light emitting step, in which a light source is caused to emit light multiple times; a light receiving step, in which each time the light is emitted, a light receiving element is exposed only once at a random timing within the light emitting time to obtain an optical physical quantity related to the vibrating object; an analysis processing step, in which a physical quantity related to the vibration of the object is calculated based on the optical physical quantity; and a compression sensing processing step, in which compression sensing is performed based on the exposure timing and the physical quantity related to the vibration of the object, thereby reconstructing the vibration movement of the object.

[0019] According to one embodiment, the program causes a computer to execute the following steps: a step of generating a first control signal, in which the first control signal is used to expose a light receiving element multiple times and obtain an optical physical quantity related to the vibrating object each time the exposure occurs; a step of generating a second control signal, in which the second control signal is used to cause a light source to emit light only once at a random timing within the exposure time each time the exposure occurs; an analysis processing step, in which the physical quantity related to the vibration of the object is calculated based on the optical physical quantity; and a compression sensing processing step, in which compression sensing is performed based on the timing of the light emission and the physical quantity related to the vibration of the object, thereby reconstructing the vibration movement of the object.

[0020] According to one embodiment, the program causes a computer to execute the following steps: a step of generating a first control signal, in which the first control signal is used to make a light source emit light multiple times; a step of generating a second control signal, in which the second control signal is used to expose a light receiving element only once at a random timing within the light emission time each time the light is emitted, so as to obtain an optical physical quantity related to the vibrating object; an analysis processing step, in which the physical quantity related to the vibration of the object is calculated based on the optical physical quantity; and a compression sensing processing step, in which compression sensing is performed based on the exposure timing and the physical quantity related to the vibration of the object, thereby reconstructing the vibration movement of the object.

[0021] Effects of the Invention

[0022] According to the present invention, it is possible to provide a vibration measurement device, a vibration measurement method, and a program using compression sensing and image analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 : is a block diagram showing the hardware configuration of the vibration measurement device 1 .

[0024] Figure 2 It is a block diagram showing the functional configuration of the control device 40 .

[0025] Figure 3 This is a diagram for explaining a method for applying compression sensing to vibration measurement.

[0026] Figure 4 This is a diagram for explaining a method for applying compression sensing to vibration measurement.

[0027] Figure 5 This is a flowchart showing a method for measuring the vibration of a structure using the vibration measuring device 1 .

[0028] Figure 6 This is a diagram for explaining a method for applying compression sensing to vibration measurement.

[0029] Figure 7 It is a diagram showing the contents and results of the verification experiment. DETAILED DESCRIPTION

[0030] <Outline>

[0031] First, the characteristics of the data science technology called compressed sensing adopted by the present invention are briefly described. Compressed sensing (compressed sensing, compressive sampling) is a framework for recovering the high-dimensional signal of the object from a small number of observations (see non-patent document 2). In the present invention, focusing on the high-speed MRI as a medical device and compressed sensing often used in astronomy, it is applied to vibration measurement by image analysis, thereby solving the above-mentioned problem.

[0032] Compressed sensing makes it possible to infer (reconstruct) extensive and detailed information from a very small amount of observation data. Compressed sensing can theoretically be applied to both spatial and temporal directions, but there are many applications that aim to restore spatial information. One reason is that in order to achieve high performance in the temporal direction, expensive equipment such as high-speed cameras are required as mentioned above.

[0033] This is because the application of compressed sensing requires a measurement technique called random sampling. Random sampling means that measurements are taken irregularly as described in the text, and measurements need to be taken at irregular times when reconstructing in the time direction. At this time, the details of the information that can be reconstructed by compressed sensing (the height of the vibration frequency that can be reconstructed) are determined by the shortness of the adjustment time of the time interval (time resolution), and vibrations that are shorter than the time resolution cannot be reconstructed. It is believed that the upper limit of the measurement interval (shooting speed) that can be set in ordinary cameras and measuring instruments is insufficient to use compressed sensing to reconstruct high-speed phenomena, and very expensive equipment such as high-speed cameras is required.

[0034] In one embodiment of the present invention, by combining a flash light source with a short light emission time, a signal generating device that controls the timing of its light emission, and a control program, even extremely high-speed vibration phenomena that are hundreds of times faster than the shooting speed of a camera can be reconstructed using very low-cost equipment.

[0035] Furthermore, in one embodiment of the present invention, compressed sensing is also applied in the spatial direction using information reconstructed in the time direction, thereby being able to reconstruct spatial vibration behavior (vibration pattern) from very few measurement points.

[0036] In the verification experiment conducted by the applicants, the frequency (the vibration mode at a certain measurement point) and the spatial vibration shape (the change mode of the shape of the structure) of a phenomenon vibrating at 3210 times / second were successfully reconstructed using a camera with a normal shooting speed of 10 frames / second. In addition, not only a single frequency, but also all frequencies and spatial vibration shapes were successfully reconstructed by individually decomposing them when a waveform obtained by synthesizing ten vibrations with different amplitudes of 90 to 160 times / second was input into the structure.

[0037] Specific embodiments to which the present invention is applied will be described in detail with reference to the accompanying drawings.

[0038] <First embodiment>

[0039] Figure 1 1 is a block diagram showing a hardware configuration of a vibration measurement device 1 according to the first embodiment of the present invention. The vibration measurement device 1 includes a light receiving unit 10 , a light source 20 , a signal generating device 30 , and a control device 40 .

[0040] The light receiving unit 10 is typically a camera that captures visible light emitted from an object to form a visible image. Alternatively, the light receiving unit 10 may be an infrared camera that is sensitive to non-visible light, an ultraviolet camera, a laser displacement meter that measures the shape and displacement of an object, etc. 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 element). In the following, for the sake of simplicity of explanation, the measurement process of the physical quantity performed by the light receiving unit 10 is referred to as "shooting", and the measured data is referred to as "image".

[0041] When a control signal is input from the outside, the light receiving unit 10 takes a picture. That is, exposure starts when the control signal is input, and ends when the predetermined exposure time has passed, and processes such as forwarding and saving the photographed data are performed. Or, when a control signal is input from the outside, the light receiving unit 10 starts taking a picture and repeats taking pictures at predetermined intervals. That is, exposure starts when the control signal is input, and ends when the predetermined exposure time has passed, and processes such as forwarding and saving the photographed data are performed. Then, if a predetermined time has passed since the last exposure, a series of processes such as exposure, forwarding, and saving the photographed data are performed again. The control signal may be, for example, a signal output by a controller such as a shutter ejector pin, or an electrical signal such as a pulse wave sequence output by the signal generating device 30. At this time, by recording the signal output time in advance on the output side of the control signal, the image capturing time can be determined.

[0042] The light source 20 is typically a flash lamp, or may be a laser oscillator, etc. That is, the light source 20 is a device that generates light necessary for the light receiving unit 10 to perform imaging.

[0043] The light source 20 emits light at a specified timing according to a control signal input from the outside. That is, the light emission starts at the input timing of the control signal, and ends when a predetermined light emission time has passed. The control signal is, for example, an electrical signal such as a pulse wave sequence output by the signal generating device 30. At this time, by recording the signal output time in advance on the output side of the control signal, the light emission time of the light source 20 can be determined. In addition, in the first embodiment, it is desired that the light emission time of the light source 20 is short, the light emission interval (the preparation time required from light emission to the next light emission) is short, and the light amount is large. The shorter the light emission time and the light emission interval of the light source 20, the more the vibration measuring device 1 can reconstruct the phenomenon of high vibration frequency.

[0044] The signal generating device 30 is a device for controlling the shooting timing of the light receiving unit 10 and the light emitting timing of the light source 20, thereby generating and outputting an electrical control signal at a preset timing. The higher the time resolution of the processing, that is, the more finely the output timing of the control signal can be adjusted, the more the vibration measuring device 1 can reconstruct the phenomenon of high vibration frequency. The time resolution is determined by the internal clock of the signal generating device 30, etc. The signal generating device 30 can be constructed using a dedicated device such as a function generator, or a general-purpose device such as a microcomputer or FPGA (Field Programmable Gate Array). The signal waveform output by the signal generating device 30 can be changed according to the specifications of the light receiving unit 10 and the light source 20, but a pulse train is usually used.

[0045] The control device 40 is typically a personal computer or a microcomputer, and a processor reads and executes a program stored in a memory, thereby realizing a processing unit which is a predetermined functional element. Figure 2 4 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 compression sensing processing unit 403.

[0046] The signal generation processing unit 401 performs processing for setting the output timing of the control signal with respect to the signal generation device 30. The output timing of the control signal is calculated based on the exposure time (shutter speed) of the light receiving unit 10, the shooting speed (the number of pictures that can be shot per unit time, determined by the exposure time + data forwarding time, etc.), the minimum light emission interval of the light source 20, the light emission time, etc. For example, the exposure time of the light receiving unit 10 can be set as long as possible within the settable range in advance. The shooting timing of the light receiving unit 10 can be either a constant interval or irregular. In the embodiment of the present invention, the light emission timing of the light source 20 is set once during each exposure time of the light receiving unit 10. In addition, the light emission timing is determined according to an arbitrary probability distribution such as a uniform random number or a normally distributed 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 process of the light receiving unit 10, and not to emit light during the data forwarding time after exposure, etc. The signal generation processing unit 401 can save the setting value of the output timing of the control signal calculated here in a storage area not shown. The setting value of the output timing of the control signal can be reused multiple times. If the same light receiving unit 10 and light source 20 and shooting conditions are used as the basis, it is not necessary to recalculate each time the measurement is performed. The setting value of the output timing of the control signal calculated here is also used in the compressed sensing processing unit 403 described later.

[0047] The analysis processing unit 402 acquires randomly sampled image data, that is, acquires a series of image data captured by the light receiving unit 10 under the control of the vibration measurement device 1. Then, local physical quantities related to the vibration of the object represented by displacement and deformation are calculated from each acquired image. For this analysis, known techniques such as digital image correlation (DIC) and sampling moiré fringe method can be used.

[0048] The compressive sensing processing unit 403 performs compressive sensing using the time series data of the physical quantity calculated by the analysis processing unit 402 and the setting value of the output timing of the control signal created by the signal generation processing unit 401 .

[0049] Figure 3 This is a diagram for explaining a specific method for applying compression sensing to vibration measurement.

[0050] Compressed sensing is a technique for estimating an unknown vector x based on linear observations. Even if the signal x cannot be observed directly, if the observed signal x can be multiplied by the observation matrix A (linear observation), x can be estimated (reconstructed) using the observation result y and the observation matrix A. In addition, detailed descriptions of the specific steps of reconstruction are omitted in this manuscript (see Non-Patent Document 2).

[0051] In the present embodiment, the unknown vector x is a waveform representing the vibration of the object (change in a physical quantity represented by displacement or strain with the passage of time).

[0052] As the observation matrix A, a matrix that represents the timing of capturing the observation, i.e., the timing of the object can be used. For example, it is possible to assume the time slots after dividing the exposure time under the time resolution, and generate a bit string in which 1 is set in the time slot when the light source 20 emits light and 0 is set in the time slot when no light is emitted, and set it as an element of the matrix. To give a specific example, when the exposure time is 0.6 seconds, the time resolution is 0.1 seconds (the light emission timing of the light source 20 can be controlled at 0.1 second intervals), and the light emission timing is 0.4 seconds after the exposure, the bit string becomes 000010. In the case where M shots are taken, M bit strings can be generated. If Figure 3 As shown, by configuring these M bit strings in M ​​rows, the observation matrix A can be constructed.

[0053] As the observation result y, a local physical quantity represented by displacement or deformation calculated by the analysis processing unit 402 based on the captured image can be used. Figure 3 As shown, by configuring M physical quantities in M ​​rows, an observation result y can be generated.

[0054] In addition, if Figure 4 As shown, when compressive sensing is applied for reconstruction, it is necessary to set a basis, i.e., a reference element constituting vibration (see Non-Patent Document 2). The basis can be a basis generally used in signal decomposition, such as a discrete Fourier basis, a continuous wavelet basis, or a discrete wavelet basis.

[0055] Next, use Figure 5 A method for measuring the vibration of a structure using the vibration measuring device 1 will be described with reference to a flowchart of FIG.

[0056] S101:

[0057] A pattern for image analysis is set on the surface of the object to be measured. For example, a pattern is applied to the surface of the object, or a seal is attached. The shape of the pattern is arbitrary, for example, a geometric pattern such as a circle or AR mark, a random pattern, a regular or irregular grid pattern, etc. can be used. Natural patterns, stains, etc. formed on the surface of the object can also be used as patterns.

[0058] In addition, when a pattern using a retro-reflective material is used, the influence of ambient light (such as lighting, etc.) can be suppressed and stable measurement can be performed. Retro-reflective material refers to a material that reflects light from a light source in a light path that is almost the same as the incident light. By arranging the light source 20 near the light receiving unit 10, the influence of ambient light other than the light source 20 can be suppressed when the light receiving unit 10 is shooting, and stable measurement can be performed.

[0059] S102:

[0060] The light receiving unit 10 is set so that the entire measurement range is contained in the image, and the position of the light source, the light quantity, and the aperture of the lens are adjusted so that the image analysis pattern is captured only when the light source 20 emits light.

[0061] S103:

[0062] The signal generation processing unit 401 of the control device 40 calculates a setting value of the output timing of the control signal, and sets it in the signal generation device 30. That is, the setting value is written in a storage area (not shown) of the signal generation device 30.

[0063] The signal generation processing unit 401 may calculate the setting value of the output timing of the control signal each time, but if there is experience of previous measurements under the same conditions, the setting value calculated and stored in the past may be reused.

[0064] S104:

[0065] The signal generating device 30 is connected to the external control terminal of the light receiving unit 10 and the external control terminal of the light source 20. The signal generating device 30 outputs the control signal to the light receiving unit 10 and the light source 20 according to the setting value of the output timing of the control signal. As a result, the light receiving unit 10 and the light source 20 record the vibration of the object at the timing calculated in advance by the signal generation processing unit 401.

[0066] S105:

[0067] The analysis processing unit 402 analyzes the image acquired by the light receiving unit 10 and acquires time series data (random sampling data) of a physical quantity.

[0068] S106:

[0069] The compressed sensing processing unit 403 obtains the spatial mode of vibration with a frequency very high compared to the shooting interval of the light receiving unit 10 and the reconstruction result after frequency decomposition based on the random sampling data of the physical quantity obtained in S105 and the setting value of the output timing of the control signal generated by the signal generation processing unit 401.

[0070] <Second embodiment>

[0071] In the first embodiment, the light source 20 emits light only once at a random timing during the exposure process of the light receiving unit 10. On the other hand, in the second embodiment, it is characterized in that the light receiving unit 10 is exposed only once at a random timing during the light emission process of the light source 20. Hereinafter, the vibration measurement device 1 involved in the second embodiment will be described with the focus on the differences from the first embodiment. The description of the configuration and operation common to the first embodiment will be appropriately omitted.

[0072] The hardware configuration of the vibration measuring device 1 according to the second embodiment is as follows: Figure 1 shown.

[0073] In the second embodiment, it is desirable that the exposure time (shutter speed) of the light receiving unit 10 is short, the shooting speed (the number of images that can be shot per unit time, determined by the exposure time + data transfer time, etc.) is fast, and the sensitivity is high. The shorter the exposure time of the light receiving unit 10 and the faster the shooting speed, the more the vibration measurement device 1 can reconstruct the phenomenon of high vibration frequency.

[0074] In the second embodiment, the light emission time of the light source 20 is set as long as possible in advance within a settable range, for example. The light emission timing of the light source 20 may be regular or irregular.

[0075] The exposure timing of the light receiving unit 10 is set once during each light emission time of the light source. In addition, the exposure timing is determined according to any probability distribution such as uniform random numbers or normal distribution random numbers based on the time resolution of the signal generating device 30. That is, the light receiving unit 10 is exposed only once at a random timing during each light emission process of the light source 20.

[0076] In addition, the time interval between each light emission of the light source 20 is preferably greater than 0. When the time interval exceeds 0, the light source 20 emits light intermittently. That is, it flickers. For example, when the light emission time is 0.6 seconds each time and the time interval between each light emission is 0.1 seconds, the light source 20 alternately repeats light emission (0.6 seconds) and no light emission (0.1 seconds) in a flickering manner. On the other hand, when the time interval is 0, the light source 20 becomes continuous light, and for example, sunlight can be used as the light source 20. For example, when the light emission time is 0.6 seconds each time and the time interval between each light emission is 0, the light source 20 objectively becomes continuous light, but the vibration measurement device 1 regards the light source 20 as repeating 0.6 seconds of light emission in the time interval 0 and processes it.

[0077] Figure 6 This is a diagram for explaining a specific method for applying compression sensing to vibration measurement in the second embodiment.

[0078] In the present embodiment, a matrix representing the timing of capturing the observation, i.e., the timing of capturing the object, can be used as the observation matrix A. For example, it is possible to make assumptions about the time slots after dividing the light emission time under the time resolution, generate a bit string in which 1 is set in the time slot when the light receiving unit 10 is exposed and 0 is set in the time slot when there is no exposure, and set it as an element of the matrix. To give a specific example, when the light 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 light emission, the bit string becomes 000010. When M shots are taken, M bit strings can be generated. If Figure 3 As shown, by configuring these M bit strings in M ​​rows, the observation matrix A can be created.

[0079] The unknown vector x and the observation result y can be generated in the same manner as in the first embodiment.

[0080] A method for measuring the vibration of a structure using the vibration measuring device 1 according to the second embodiment is as follows: Figure 5 shown.

[0081] <Verification experiment>

[0082] The applicant conducted a vibration measurement experiment using the vibration measurement device 1 having the configuration according to the first embodiment of the present invention. Figure 7 The contents and results are shown below.

[0083] Content: Using a vibration table, a composite vibration of 170 Hz and 1130 Hz was input into the center of an aluminum alloy flat plate. The flat plate in this state was photographed using a light receiving unit 10 having a shooting speed of 10 Hz (10 fps, i.e., 10 frames per second). During the exposure process of the light receiving unit 10, the light source 20 was made to emit light once at a random timing.

[0084] Results: The compressed sensing processing unit 403 performs mode decomposition on the synthesized vibration and extracts the modes of 170 Hz and 1130 Hz. This is equivalent to 226 times the Nyquist frequency. Thus, it is proved that the vibration measurement device 1 is capable of mode decomposing waveforms above the Nyquist frequency. In addition, the waveforms of the modes of 170 Hz and 1130 Hz decomposed at this time are almost the same as the waveforms obtained by the finite element method (FEM). Thus, the correctness of the measurement results performed by the vibration measurement device 1 is proved.

[0085] In another experiment, a 10 Hz camera was used to identify a mode at 3210 Hz (642 times the Nyquist frequency), and the frequency resolution was 10. In addition, it was confirmed that the system can cope with stable, random, and damped structural vibrations.

[0086] The embodiments of the present invention are described above, but the present invention is not limited to the above embodiments and can be appropriately changed without departing from the scope of the present invention. Within the scope of the present invention, any constituent element of the embodiment can be modified or any constituent element of the embodiment can be omitted.

[0087] In addition, the information processing of the present invention can be implemented by hardware or by CPU executing a computer program. The computer program can be provided by a computer through various types of non-transitory computer readable media or transitory computer readable media.

[0088] Description of Reference Numerals

[0089] 1: Vibration measurement device;

[0090] 10: light receiving part;

[0091] 20: light source;

[0092] 30: signal generating device;

[0093] 40: control device;

[0094] 401: signal generation processing unit;

[0095] 402: analysis processing unit;

[0096] 403: Compressed sensing processing unit.

Claims

1. A vibration measuring device, wherein: The vibration measuring device comprises: a light receiving unit that exposes the light receiving element a plurality of times and acquires an optical physical quantity related to the vibrating object each time the exposure occurs; a light source that emits light only once at a random timing within the exposure time during the exposure; and Control device, The control device comprises: 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 performs compressive sensing based on the timing of the light emission and a physical quantity related to the vibration of the object, thereby reconstructing the vibration behavior of the object.

2. A vibration measuring device, wherein: The vibration measuring device comprises: a light receiving unit that exposes the light receiving element only once at a random timing within a predetermined time, and repeats a step of acquiring an optical physical quantity related to a vibrating object a plurality of times; and Control device, The control device comprises: 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 performs compressive sensing based on the exposure timing and a physical quantity related to the vibration of the object, thereby reconstructing the vibration behavior of the object.

3. A vibration measurement method, wherein: The vibration measurement method comprises: a light receiving step of exposing the light receiving element a plurality of times and acquiring an optical physical quantity related to the vibrating object each time the exposure occurs; a light emitting step, in which, each time the exposure is performed, the light source is caused to emit light only once at a random timing within the exposure time; 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 is performed based on the timing of the light emission and a physical quantity related to the vibration of the object, thereby reconstructing the vibration behavior of the object.

4. A vibration measurement method, wherein: The vibration measurement method comprises: a light emitting step, in which the light source is caused to emit light a plurality of times; a light receiving step, in which, each time the light is emitted, the light receiving element is exposed only once at a random timing within the light emission time, to obtain an optical physical quantity related to the vibrating object; 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 is performed based on the exposure timing and a physical quantity related to the vibration of the object to reconstruct the vibration behavior of the object.

5. A program, wherein: The program is used to make the computer execute the following steps: A step of generating a first control signal, in which the first control signal is used to expose the light receiving element a plurality of times, and to obtain an optical physical quantity related to the vibrating object each time the exposure occurs; A step of generating a second control signal, in which the second control signal is used to make the light source emit light only once at a random timing within the exposure time during 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 is performed based on the timing of the light emission and a physical quantity related to the vibration of the object, thereby reconstructing the vibration behavior of the object.

6. A program, wherein: The program causes the computer to execute the following steps: A step of generating a first control signal, in which the first control signal is used to make the light source emit light multiple times; A step of generating a second control signal, in which the second control signal is used to expose the light receiving element only once at a random timing within the light emission time each time the light emission occurs, so as to obtain an optical physical quantity related to the vibrating object; an analysis processing step of calculating a physical quantity related to the vibration of the object based on the optical physical quantity; as well as A compressive sensing processing step is performed based on the exposure timing and a physical quantity related to the vibration of the object to reconstruct the vibration behavior of the object.

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