JP6594366B2 - Measuring apparatus, measuring method and measuring program - Google Patents

Description

  The present invention relates to a measuring apparatus, a measuring method, and a measuring program for measuring luminescence intensity when a stress is applied to a stress luminescent substance.

  In recent years, CAE (Computer Aided Engineering) is often used in the design of various products and parts. The design process includes inspection of resistance to strain (stress) and the like.

  As a technique for measuring the strain (stress) of the object, it is conceivable to use a strain (stress) measurement system that calculates the strain (stress) of the object to be measured (see, for example, Patent Document 1 or Patent Document 2). . According to the strain (stress) measurement system described in Patent Document 1 or Patent Document 2, a stress luminescent material is applied to an object to be measured, and based on the luminescence intensity when a load is applied to the applied stress luminescent material. A region where distortion occurs in the object to be measured is detected.

JP 2006-284393 A Japanese Patent Laid-Open No. 2006-180637

  Here, if the surface of the object 110 is uneven, the thickness of the stress-stimulated luminescent material applied to the object 110 is not uniform due to the unevenness. Therefore, the influence of the light emission intensity due to the difference in the coating thickness is superimposed on the light emission intensity measured when a load is applied to the stress luminescent material. Therefore, even if the strain generated in the object to be measured is measured based on the light emission intensity when a load is applied to the applied stress luminescent material, as in the technique described in Patent Document 1 or Patent Document 2, The light emission intensity is affected by the difference in coating thickness, and a correct measurement result cannot be obtained. Therefore, the technique described in Patent Document 1 or Patent Document 2 has a problem that it is difficult to quantitatively evaluate distortion generated in the object to be measured.

  Therefore, the present invention has been made in view of the above problems, and the influence of the difference in the thickness of the stress-stimulated luminescent material applied to the object is reduced from the luminescence intensity when a load is applied to the applied stress-stimulated luminescent material. Another object is to provide a measuring device, a measuring method, and a measuring program that can be removed.

In order to solve the above problems, a measurement device according to one embodiment of the present invention includes an acquisition unit that acquires a captured image obtained by capturing an object to which a stress luminescent substance is applied, and a stress obtained from the captured image acquired by the acquisition unit. A measurement unit that measures the first emission intensity, which is the emission intensity when the luminescent substance transitions from the excited state to the ground state, the first emission intensity measured by the measurement unit, and the stress applied with a uniform coating thickness An estimation unit that compares the second emission intensity, which is the emission intensity when the luminescent substance transitions from the excited state to the ground state, and estimates the application thickness of the stress luminescent substance on the object based on the comparison result; A calculation unit that calculates the emission intensity corrected to the emission intensity when the application thickness of the stress luminescent material is made uniform from the first emission intensity using the application thickness estimated by the estimation unit.

  In the measurement device according to one embodiment of the present invention, the measurement unit calculates the emission intensity when the stress-stimulated luminescent material that has been excited by being irradiated with light having a short wavelength transitions to the ground state by being heated. The first emission intensity may be measured.

  In the measurement apparatus according to one embodiment of the present invention, the acquisition unit may acquire a captured image captured by continuing the exposure state while the stress-stimulated luminescent substance transitions from the excited state to the ground state. .

  In the measurement device according to one embodiment of the present invention, the acquisition unit acquires a plurality of captured images that are sequentially captured while the stress-stimulated luminescent substance transitions from the excited state to the ground state, and the measurement unit includes the plurality of sequentially captured images. The first emission intensity may be measured by integrating the emission intensity calculated from each of the captured images.

  In the measurement device according to one embodiment of the present invention, the estimation unit is configured so that the stress luminescent material applied at a uniform application thickness with respect to the material having the first light emission intensity and the same reflectance as the target object is in an excited state. A comparison may be made with the second emission intensity, which is the emission intensity in the case of transition to the ground state, and the application thickness of the stress luminescent substance on the object may be estimated based on the comparison result.

  In the measurement apparatus according to one aspect of the present invention, the estimation unit calculates a difference between the first emission intensity and the second emission intensity for each predetermined region of the target, and calculates the difference and the uniform coating thickness. The thickness of the stress luminescent substance may be estimated based on the thickness of the material.

  The measurement method according to one aspect of the present invention includes an acquisition step of acquiring a captured image obtained by capturing an object coated with a stress luminescent substance, and the stress luminescent substance transits from an excited state to a ground state from the acquired captured image. A measurement step for measuring the first emission intensity, which is the emission intensity in the case, and the light emission when the stressed luminescent substance applied with a uniform application thickness transitions from the excited state to the ground state. A second emission intensity that is an intensity, and an estimation step for estimating the application thickness of the stress-stimulated luminescent substance on the object based on the comparison result, and the first emission intensity using the estimated application thickness. And calculating a third emission intensity which is an emission intensity when the application thickness of the stress luminescent substance is made uniform.

  The measurement program according to one embodiment of the present invention includes an acquisition function for acquiring a captured image obtained by capturing an object coated with a stress luminescent substance in a computer, and the stress luminescent substance from an excited state to a ground state from the acquired captured image. The measurement function for measuring the first emission intensity, which is the emission intensity in the case of transition to, and the measured first emission intensity and the stress-stimulated luminescent material applied with a uniform coating thickness transition from the excited state to the ground state The second emission intensity, which is the emission intensity in the case, and based on the comparison result, the estimation function for estimating the application thickness of the stress-stimulated luminescent substance on the object and the estimated application thickness And a calculation function for calculating a third emission intensity which is an emission intensity when the application thickness of the stress luminescent substance is made uniform from the emission intensity.

  The measuring device according to one embodiment of the present invention can reduce or eliminate the influence of the difference in the thickness of the stress-stimulated luminescent material applied to the object from the luminescence intensity when a load is applied to the applied stress-stimulated luminescent material. Is possible.

It is a figure which shows the structural example of a measurement system. It is a figure which shows the relationship between the structural example of the target object 110 with which the stress light-emitting substance was apply | coated, and the emitted light intensity at the time of applying a load to this target object 110. FIG. It is a figure which shows the relationship between the position of the target object 110, and emitted light intensity when a load is given to the target object 110. FIG. It is a flowchart which shows the operation example of a measuring apparatus. It is a flowchart which shows the other operation example of a measuring apparatus. (A) is a figure which shows an example of the distortion (stress) light emission state when the load is not applied to the object. (B) is a figure which shows an example in case the distortion (stress) distribution of the object shown to (a) is output by a color contour. (C) is a figure which shows an example of the distortion (stress) light emission state in case the load is applied to the object. (D) is a figure which shows an example in case the distortion (stress) distribution of the object shown to (c) is output by a color contour. It is another figure which shows the structural example of a measurement system.

  Hereinafter, a measuring apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.

<Embodiment>
<Configuration>
FIG. 1 is a diagram illustrating a configuration of a measurement system including the measurement apparatus 100. The measurement system focuses on the fact that the stress-stimulated luminescent substance emits light with a predetermined probability in the process of returning from the excited state to the ground state, and estimates the coating thickness of the stress-stimulated luminescent substance using the luminescence intensity of the luminescence. Then, the measurement system corrects the emission intensity when a load is applied to the stress-generating substance based on the estimated application thickness to the emission intensity when the application thickness is uniform, and based on the corrected emission intensity. The distortion generated in the object 110 is quantitatively calculated.

  In addition, the measurement system can also generate the object 110 by dividing the luminescence intensity when a stress is applied to the stress-generating substance by the luminescence intensity of the stress luminescent substance from the excited state to the ground state. The distortion can be calculated quantitatively. The stress-stimulated luminescent material emits light with respect to the load, and the luminescence intensity at that time superimposes the difference in the amount of luminescence due to the application thickness, transmittance, reflectance, etc. of the stress-stimulated luminescent material. Therefore, by using a value obtained by dividing the light emission intensity when a load is applied to the stress-generating substance by the light emission amount obtained by integrating the light emission amount from the light emission amount to the ground state from the excited state to the ground state, the object 110 is used. The generated distortion can be calculated quantitatively.

  FIG. 2 is a diagram illustrating a relationship between a configuration example of the object 110 to which the stress-stimulated luminescent material is applied and light emission intensity when a load is applied to the object 110. As shown in FIG. 2A, when the surface of the object 110 is uneven, the thickness of the stress luminescent material applied to the object 110 is not uniform due to the unevenness. In addition, if the stress-stimulated luminescent substance is a paint, the paint may not be applied with a uniform thickness due to the wettability and liquid pool of the paint. That is, the application thickness of the stress-stimulated luminescent material applied to the object 110 varies depending on the area where the object 110 is applied. Here, if the application thickness of the stress-stimulated luminescent material applied to the object 110 is large, the luminescence intensity measured when a load is applied is larger than that in other regions. As a result, the influence of the light emission intensity due to the difference in the coating thickness is superimposed on the light emission intensity measured when a load is applied to the stress luminescent material. Further, the transmittance of the stress luminescent material, the light reflectance of the object 110, and the like differ depending on the application thickness of the stress luminescent material, and these effects are also affected when a load is applied to the stress luminescent material. It will be superimposed on the emission intensity. As a result, as shown in FIG. 2B, the light emission intensity of the stress luminescent material measured when a load is applied to the object 110 is caused by the difference in the application thickness of the stress luminescent material or the application thickness. The influence of the emission intensity due to the difference in the transmittance of the stressed luminescent material and the reflectance of the object 110 is taken into consideration. Therefore, there arises a problem that it is difficult to quantitatively evaluate the distortion generated in the object 110.

Therefore, the measurement system is applied with the light emission intensity (first light emission intensity) when the stress luminescent material applied to the object 110 transitions from the excited state to the ground state, and with a uniform application thickness on the flat test piece. Based on the second emission intensity, which is the emission intensity when the stressed luminescent substance transitions from the excited state to the ground state, the application thickness of the stressed luminescent substance on the object 110 is estimated. Based on the estimated coating thickness, the light emission intensity when a load is applied to the stress-generating substance is corrected to the light emission intensity when the coating thickness is uniform. Thereby, it is possible to calculate the light emission intensity corrected by reducing or eliminating the influence due to the difference in the application thickness of the stress luminescent material, and it is possible to quantitatively calculate the distortion generated in the object 110.

  Further, the measurement system divides the luminescence intensity when a stress is applied to the stress-generating substance by the luminescence intensity obtained by integrating the luminescence intensity (first luminescence intensity) when transitioning from the excited state to the ground state. Further, it is possible to calculate the light emission intensity in which the influence due to the difference in the application thickness of the stress luminescent material is reduced or eliminated, and it is possible to quantitatively calculate the distortion generated in the object 110.

  Further, the measurement system images the object 110 coated with the stress luminescent material, and based on the emission intensity (luminance) measured from the image (captured image) obtained by imaging, distortion applied to the object 110 The amount (strain (stress)) can also be calculated. Furthermore, the measurement system can display an image that has been color-contoured based on the distortion amount calculated by the measurement apparatus 100. The measuring apparatus 100 according to such a system will be described in detail.

  As illustrated in FIG. 1, the measurement apparatus 100 includes an acquisition unit 101, a measurement unit 102, an estimation unit 103, a calculation unit 104, an output unit 105, and a storage unit 106.

  The acquisition unit 101 is a communication interface having a function of acquiring a captured image 130 captured by the imaging unit 120. The acquisition unit 101 may receive the video captured by the imaging unit 120 as it is, or may be received by a server device (not shown) or the like in which the video captured by the imaging unit 120 is connected to the imaging unit 120 via a network. It is good also as acquiring what was memorize | stored. The acquisition unit 101 may be connected to the imaging unit 120 or an external server device via a wired or wireless network, and any communication protocol can be used for communication as long as the captured image 130 can be acquired. It may be. The acquisition of the captured image 130 by the acquisition unit 101 may be to acquire images sequentially captured by the imaging unit 120, or each frame is taken as a captured image in order from the video captured by the imaging unit 120. You may acquire.

  The object 110 to be measured for strain (stress) may be any object as long as a stress luminescent substance is attached to the surface.

  Here, the stress luminescent substance (paint, material) emits light in response to various loads such as friction, impact, vibration, compression, tension, twisting, and strain (stress) luminescence is applied. This refers to a phenomenon in which light is emitted with an intensity corresponding to the applied load (strain (stress)).

Examples of the stress-stimulated luminescent material include strontium aluminate (SrAl ₂ 0 ₄ : Eu) doped with europium and controlled in structure, zinc sulfide (ZnS: Mn) doped with transition metal or rare earth, or barium / calcium titanate (( Ba, Ca) TiO ₃ : Pr), calcium yttrium aluminate (CaYAl ₃ O ₇ : Ce), and the like can be used, but they are limited to those that emit light with an intensity corresponding to strain (stress). It is not a thing.

  The stress-stimulated luminescent material transitions to an excited state when irradiated with light having a short wavelength such as ultraviolet rays. Here, the stress luminescent material has a property of emitting light with a predetermined probability in the process of returning from the excited state to the ground state. Therefore, light having a short wavelength such as ultraviolet rays is irradiated until the stress-stimulated luminescent substance is saturated and excited, and then heated to transition to the ground state. At that time, the stress-stimulated luminescent material applied to the object 110 emits light with a predetermined probability.

  Therefore, for example, the acquisition unit 101 acquires the captured image 130 captured by continuing the exposure state while the stress-stimulated luminescent material transitions from the excited state to the ground state. Specifically, the acquisition unit 101 opens the camera shutter while the stress-stimulated luminescent material applied to the object 110 transitions from the excited state to the ground state, so that the light-emitting state of the stress-stimulated luminescent material is obtained. The captured image 130 obtained by capturing is acquired. Note that the acquisition unit 101 may acquire, for example, a plurality of captured images 130 obtained by sequentially imaging the target object 110 coated with the stress-stimulated luminescent substance while the stress-stimulated luminescent substance transitions from the excited state to the ground state.

  In addition, the acquisition unit 101 acquires a plurality of captured images 130 obtained by sequentially capturing the target object 110 coated with the stress-stimulated luminescent material when a load is applied to the target object 110.

  The measurement unit 102 has a function of measuring (calculating) the luminescence intensity of the stress luminescent material applied to the object 110 from the captured image 130 acquired by the acquisition unit 101. The measurement unit 102 holds a conversion coefficient between the emission intensity (luminance) obtained from the captured image 130 captured in advance by the imaging unit 120 and the actual emission intensity (luminance), and each pixel constituting the captured image 130 The actual light emission intensity (luminance) is calculated by multiplying the light emission intensity (luminance) by the above conversion coefficient. The measurement unit 102 measures the light emission intensity of the stress luminescent material based on the calculated actual light emission intensity (luminance) of each pixel.

  For example, based on the captured image 130 acquired by the acquisition unit 101, the measurement unit 102 calculates the emission intensity of the stress luminescent material when the stress luminescent material applied to the object 110 transitions from the excited state to the ground state. Measure (calculate). In addition, the measurement unit 102, for example, from the plurality of captured images 130 sequentially captured by the acquisition unit 101 when the stress luminescent material applied to the object 110 transitions from the excited state to the ground state, The emission intensity (first emission intensity) may be measured (calculated). When calculating the luminescence intensity of the stress luminescent substance from the plurality of captured images 130 sequentially captured, the measurement unit 102 integrates the luminescence intensity calculated from each of the plurality of captured images 130 to thereby generate the stress luminescence. The emission intensity (first emission intensity) of the substance may be measured (calculated). The measurement unit 102 can be realized by, for example, a processor that reads and executes a calculation program stored in advance in the storage unit 106.

  In addition, the measurement unit 102 calculates the light emission intensity when a load is applied to the stress-stimulated luminescent material applied to the target object 110 from a plurality of captured images 130 sequentially captured when the load is applied to the target object 110. taking measurement. Specifically, the measurement unit 102 holds a conversion coefficient between the emission intensity (luminance) obtained from each of the plurality of captured images 130 captured by the imaging unit 120 in advance and the actual emission intensity (luminance). The light emission intensity (luminance) of the stress-stimulated luminescent material when a load is applied by calculating the actual luminance value by multiplying the light emission intensity (luminance) of each pixel constituting the captured image 130 by the conversion coefficient. Is measured (calculated).

  The estimation unit 103, for example, the first emission intensity measured (calculated) by the measurement unit 102 and the emission intensity (second emission) when the stress luminescent substance applied with a uniform application thickness transitions from the excited state to the ground state. Of the emission intensity). And the estimation part 103 estimates the application | coating thickness of the stress luminescent substance in the target object 110 based on the comparison result. Note that the emission intensity (second emission intensity) when the stress-stimulated luminescent material applied with a uniform application thickness transitions from the excited state to the ground state may be measured (calculated) in advance. Further, since the light emission intensity is also affected by the light reflectance of the object 110 to which the stress luminescent material is applied, when the second light emission intensity is measured (calculated) in advance, the stress luminescent material is the object 110. It is desirable to apply a uniform coating thickness to a material having the same reflectance as the above.

  The estimation unit 103, for example, for each predetermined region of the object 110, emission intensity (first emission intensity) when the stress luminescent material applied to the object 110 transitions from the excited state to the ground state, The “difference” is calculated from the emission intensity (second emission intensity) when the stress-stimulated luminescent material applied with a uniform application thickness transitions from the excited state to the ground state. Thereafter, the estimation unit 103 determines, for each predetermined region of the object 110, the stress luminescent substance in the predetermined region based on the “thickness” of the uniform coating thickness and the “difference” of the calculated emission intensity. Estimate the thickness. For example, the estimation unit 103 measures (calculates) the relationship between the “difference in luminescence intensity” and the “applied thickness of the stress luminescent material” in advance, and detects it based on the “thickness” of the uniform applied thickness. Based on the “difference” made, the application thickness of the stress luminescent substance is estimated for each predetermined region of the object 110.

  For example, the estimation unit 103 sets a uniform “application thickness” to 100 (the numerical value is just an example), and measures in advance the relationship that “the application thickness” is 10 different for every 10% difference in emission intensity ( Calculate). Then, when there are 20 differences in emission intensity for a certain area of the object 110, the estimation unit 103 estimates that the application thickness of the area is 20 different from the uniform application thickness. Whether the application thickness of the area is thin or thick (ie, 120 or 80) from the uniform application thickness, the estimation unit 103 determines that the emission intensity in the area is equal to the emission intensity of the uniform application thickness. If larger than that, it is estimated that the coating thickness of the region is larger than the uniform coating pressure (that is, 120). Conversely, when the light emission intensity in the area is smaller than the light emission intensity of the uniform application thickness, the estimation unit 103 estimates that the application thickness of the area is thinner than the uniform application pressure (that is, 80). .

  First, the calculation unit 104 corrects the “luminescence intensity when a load is applied to the stress luminescent material” measured by the measurement unit 102 using the coating thickness estimated by the estimation unit 103. Specifically, the calculation unit 104 uses the coating thickness estimated by the estimation unit 103, and the coating thickness is uniform based on the “luminescence intensity when a stress is applied to the stress luminescent material” measured by the measurement unit 102. If so, the emission intensity is calculated. That is, the calculation unit 104 calculates the light emission intensity that reduces or eliminates the influence of the difference in coating thickness on the light emission intensity.

  For example, the calculation unit 104 reduces the light emission intensity of the region estimated to have a large coating thickness while increasing the light emission intensity of the region estimated to have a thin coating thickness. The emission intensity is calculated. For example, the calculation unit 104 may calculate the light emission intensity of the entire object 110 when it is assumed that the application thickness of the other region is the thickest with reference to the case where the application thickness is the thickest. For example, the calculation unit 104 may calculate the light emission intensity of the entire object 110 when it is assumed that the application thickness of the other region is the thinnest with reference to the case where the application thickness is the thinnest. Alternatively, for example, the calculation unit 104 may calculate the light emission intensity of the entire object 110 when the coating thickness is the reference thickness with a predetermined thickness as a reference.

  For example, the calculation unit 104 divides the emission intensity when a stress is applied to the stress-generating substance by the emission amount obtained by integrating the emission intensity (first emission intensity) when transitioning from the excited state to the ground state. Based on the result, the emission intensity when the coating thickness is uniform may be calculated.

  FIG. 3 is a diagram illustrating the relationship between the position of the object 110 and the light emission intensity when a load is applied to the object 110. As shown in FIG. 3A, the light emission intensity measured (calculated) by the measurement unit 102 includes the influence of the light emission intensity due to the difference in the application thickness of the stress luminescent material. Therefore, by dividing (removing) the influence of the light emission intensity caused by the difference in the application thickness of the stress light-emitting substance, the light emission intensity when the stress light-emitting substance is uniformly applied is calculated. As a result, as shown in FIG. 3B, it is possible to calculate the emission intensity from which the difference in coating thickness is removed. And the calculation part 104 can calculate the distortion which arose in the target object 110 using the light emission intensity | strength from which the influence of application | coating thickness was removed, ie, the light emission intensity calculated only from having added the load.

  Next, a process for calculating the distortion amount of the object 110 will be described. The calculation unit 104 has a function of calculating the distortion amount of the object 110 based on the light emission intensity from which the influence of the coating thickness is removed. Here, the light emission intensity (luminance) due to strain (stress) in the stress luminescent material can be expressed in the form of background light + (strain amount × strain rate). More specifically, the light emission intensity (luminance) L (t) at time t can be expressed by the following mathematical formula (1).

In the above formula (1), L (t) is the emission intensity (luminance) from which the influence of the coating thickness is removed. L _bg is a reference light emission intensity (reference light emission luminance) serving as a reference, and is the light emission intensity (luminance) of the object 110 in a state where light emission due to distortion (stress) is not performed. It corresponds to. k is a predetermined coefficient. Here, k is an emission intensity (luminance) obtained in the imaging apparatus by giving an excitation state of a specific level to a substance having a specific reflectivity to which a stress luminescent substance having a specific thickness is applied in advance, and the intensity at that time. The strain amount can be determined by simultaneously measuring with a strain gauge or the like (calibration at an arbitrary point), but is not limited thereto.

  In the above formula (1), ε is a strain amount, and ∂ε / ∂t is a strain rate. The strain rate means a time change of strain. The calculation unit 104 calculates the distortion amount ε using the above formula (1). The calculation unit 104 calculates the distortion amount of each predetermined range using the above-described equation (1) for each predetermined range of the captured image. Here, as an example, the predetermined range is a one-pixel range, but is not limited thereto. A plurality of pixels may be within a predetermined range. In this case, the average value of the light emission intensity (luminance) of each pixel may be used as the light emission intensity (luminance) of the predetermined range. The emission intensity of each pixel and the emission intensity within a predetermined range are emission intensity (luminance) from which the influence of the coating thickness is removed.

  In the above equation (1), when the distortion amount ε (i) is calculated for the i th (time t) frame, the above equation (1) is obtained for the i−1 th (time t−1) frame. By using the calculated strain amount ε (i−1), it can be transformed into the following equation (2).

  By transforming equation (2), the following equation (3) can be derived.

  In Expression (3), L (i) is a light emission intensity (luminance) from which the influence of the coating thickness is removed, and is a calculated value (that is, a known value). Lbg is a reference light emission intensity (reference light emission) measured in advance. (Luminance) is a known value, and k is a known value because it is a predetermined coefficient. Also, ε (i−1) is a known value because it is a distortion amount calculated for the i−1th frame. Therefore, in the above equation (3), the only unknown value is ε (i). Therefore, the calculation unit 104 can calculate the distortion amount ε (i) for the i-th frame by solving the quadratic equation shown in the above equation (3).

  The calculation unit 104 can be realized by, for example, a processor that reads and executes a distortion measurement program stored in advance in the storage unit 106 included in the measurement apparatus 100. Further specific examples regarding the calculation of the distortion amount will be described later.

  The output unit 105 is a communication interface having a function of outputting information related to the distortion amount calculated by the calculation unit 104. The output unit 105 may be connected to the external display device 150 via a wired or wireless network. If the output unit 105 can transmit information on the distortion generation region and information on the amount of distortion, the communication protocol used for communication is It does not matter. The information on the distortion amount may be the distortion amount value itself calculated by the calculation unit 104, or may be information obtained by processing the distortion amount value (for example, a color contoured image). When outputting information obtained by processing the distortion amount, the measuring apparatus 100 includes an image generation unit (not shown) that generates a color-contoured image based on the pixel-unit distortion amount calculated by the calculation unit 104. It is good also as providing. The image generation unit can generate a color-contoured image based on strain (stress) (strain amount) as in the case of conventional CAE.

  Based on the information regarding the amount of distortion output from the output unit 105, for example, the display device 150 can display it as a color contour image showing a strain (stress) distribution. The display device 150 can be realized by a generally known LCD, organic EL display, or the like. In addition, as the display device 150, for example, a monitor of a mobile terminal or a monitor of a tablet terminal may be used.

  The storage unit 106 is a storage medium having a function of storing various data and programs required for the operation of the measuring apparatus 100. The storage unit 106 can be realized by, for example, an HDD (Hard Disc Drive), an SSD (Solid State Drive), a flash memory, or the like, but is not limited thereto. The storage unit 106 includes, for example, a measurement program for the measurement unit 102 to calculate the light emission intensity (luminance) of each pixel from the captured image 130, a distortion measurement program for the calculation unit 104 to calculate a distortion amount, and a calculation unit 104 The calculated distortion amount is stored.

<Operation>
FIG. 4 is a flowchart illustrating an operation example of the measurement apparatus 100. FIG. 4 is a flowchart illustrating an operation example in the case where the calculation unit 104 calculates the light emission intensity in which the influence of the difference in coating thickness on the light emission intensity is reduced or eliminated.

(Step S101)
In step S101, the acquisition unit 101 of the measurement apparatus 100 captures a captured image 130 obtained by imaging the light emission state of the stress luminescent material when the stress luminescent material applied to the object 110 transitions from the excited state to the ground state, for example. To get. The acquisition unit 101 transmits the acquired captured image 130 to the measurement unit 102 and proceeds to step S102.

(Step S102)
In step S102, the measurement unit 102 emits light of the stress luminescent material when the stress luminescent material applied to the object 110 transitions from the excited state to the ground state based on the captured image 130 acquired by the acquisition unit 101. Measure (calculate) strength. The measurement unit 102 transmits the measured luminescence intensity of the stress luminescent material to the estimation unit 103, and proceeds to step S103.

(Step S103)
In step S103, the estimation unit 103, for example, emits light when the first luminescence intensity measured (calculated) by the measurement unit 102 and the stress luminescent material applied with a uniform coating thickness transition from the excited state to the ground state. The second emission intensity, which is the intensity, is compared, and the application thickness of the stress luminescent substance on the object 110 is estimated based on the comparison result.

(Step S104)
In step S104, the calculation unit 104 calculates the corrected emission intensity by reducing or eliminating the influence of the difference in coating thickness on the emission intensity. Thereby, the measuring apparatus 100 can measure (calculate) the light emission intensity calculated from only the light emission intensity from which the influence of the coating thickness is removed, that is, the load, on the object 110.

  FIG. 5 is a flowchart showing another operation example of the measurement apparatus 100. FIG. 5 is a flowchart illustrating an operation example when the measuring apparatus 100 calculates the distortion amount based on the light emission intensity from which the influence of the coating thickness is removed.

(Step S201)
In step S <b> 201, the acquisition unit 101 of the measurement apparatus 100 acquires a reference image (which may be the 0th (first) frame of the video) that captures a state in which no load is applied to the object 110 to which the stress luminescent material is applied. To do. The acquisition unit 101 transmits the acquired reference image to the measurement unit 102, and the process proceeds to step S202.

(Step S202)
In step S202, the measurement unit 102 measures the reference light emission intensity (reference luminance) L _{bg serving} as a reference for each pixel (predetermined range) constituting the reference image transmitted by the acquisition unit 101, and the process _proceeds to step S203. .

(Step S203)
In step S203, the acquisition unit 101 acquires an image obtained by imaging the state (process) in which a load is applied to the object 110 to which the stress-stimulated luminescent substance is applied from the imaging unit 120, and the process proceeds to step S204.

(Step S204)
In step S204, the measuring apparatus 100 initializes the frame number i related to the process to 1, and proceeds to step S205.

(Step S205)
In step S205, the measurement unit 102 acquires the i-th frame from the transmitted video, and proceeds to step S206.

(Step S206)
In step S206, the calculation unit 104 determines the influence of the difference in coating thickness on the light emission intensity based on the light emission intensity Li of each predetermined range (each pixel) of the object 110 of the i-th frame measured by the measurement unit 102. The reduced or eliminated emission intensity is calculated, and the process proceeds to step S207.

(Step S207)
In step S207, the calculation unit 104 determines whether or not the storage unit 106 stores the distortion amount ε (i−1) calculated for the (i−1) th frame. If stored (YES), the process proceeds to step S208. If not stored (NO), the process proceeds to step S210.

(Step S208)
In step S208, the calculation unit 104 calculates the distortion amount ε (i) of each pixel in the i-th frame based on the emission intensity obtained by reducing or eliminating the influence of the difference in coating thickness on the emission intensity. 1) Calculate using (3). Thereafter, the process proceeds to step S209.

(Step S209)
In step S209, the measuring apparatus 100 determines whether or not a distortion amount calculation process end input has been received, and if it has been received (YES), the process ends. If not received (NO), the process proceeds to step S210.

(Step S210)
In step S210, the measuring apparatus 100 adds 1 to i and returns to step S205.

<Specific example of distortion amount calculation>
From here, a specific example of calculation of the amount of distortion will be shown using a specific example.

First, the emission intensity (luminance) of the object 110 is measured in a state where no load is applied to the object 110 (the state shown in FIG. 6A). The light emission intensity (luminance) at this time is set to “0”. As a result, the reference emission intensity (reference luminance) L _bg can be set to 0 and ignored. Actually, the emission intensity obtained by reducing or eliminating the influence of the difference in coating thickness calculated by the calculation unit 104 on the emission intensity is _defined as L _{bg and} the emission intensity (luminance) when a subsequent load is applied is calculated as L _bg. Use the value to subtract. As the color contour at this time, for example, a color contour showing a uniform strain (stress) distribution is output as shown in FIG.

  Next, as shown in FIG. 6C, when a load is applied to the object 110, the stress-stimulated luminescent material emits light according to the strain (stress). At this time, it is assumed that the strain (stress) emission intensity (luminance) for 1/60 seconds is “1” after the load is applied. At the time of 1/60 seconds, the previous distortion amount ε (i−1) is “0” because it is the distortion amount at time “0”. Then, when applied to the above equation (2), the following relational equation (4) can be obtained.

Here, in order to simplify the description, it is assumed that the coefficient k is 1/60. Then, since L (1/60) = 1, a relational expression of ε (1/60) ² = 1 can be obtained. Therefore, a positive solution of this relational expression is obtained as a distortion amount ε ( 1/60). That is, in this example, ε (1/60) = 1 can be obtained.

  Next, it is assumed that the light emission intensity calculated by the calculation unit 104 at 2/60 seconds is “20”. Then, the following relational expression (5) can be obtained.

  Since the emission intensity at the time of L (2/60) is 20, ε (2/60) = − 4 or 5 is obtained. Using the positive value of these values as a solution, the calculation unit 104 can calculate “5” as the distortion amount ε (2/60) at the time point of 2/60 seconds.

  Next, it is assumed that the emission intensity calculated by the calculation unit 104 is 50 at 3/60 seconds. Then, in this case as well, the distortion amount ε (3/60) can be obtained by solving the following equation (6) in the same manner.

  By solving Equation (6) above, the calculation unit 104 calculates ε (3/60) = 10. Therefore, as in this specific example, when k is a time difference, the reference light emission intensity Lbg is 0, and the light emission intensity calculated by the calculation unit 104 is a, the calculation unit 104 solves the quadratic expression shown in the following equation (7). The positive solution can be calculated as the distortion amount ε (i).

  As a result, for example, as shown in FIG. 6D, an image that has been color-contoured based on the calculated distortion amount can be output.

<Summary>
In the measuring apparatus 100, the stress-stimulated luminescent material applied to the object 110 was applied with a uniform application thickness on the flat test piece with the emission intensity (first emission intensity) when the excited state transits from the ground state to the ground state. Based on the luminescence intensity (second luminescence intensity) when the stress luminescent substance transitions from the excited state to the ground state, the application thickness of the stress luminescent substance on the object 110 is estimated. Based on the estimated coating thickness, the light emission intensity when a load is applied to the stress-generating substance is corrected to the light emission intensity when the coating thickness is uniform. Thereby, it is possible to calculate the light emission intensity in which the influence due to the difference in the application thickness of the stress luminescent material is reduced or eliminated, and it is possible to quantitatively calculate the distortion generated in the object 110.

  Further, the measuring apparatus 100 can generate an image of a strain (stress) distribution that is color-contoured based on the calculated strain amount. Accordingly, the strain (stress) distribution by CAE can be verified by comparing the color contour image of the strain (stress) distribution by CAE with the color contour image based on the strain amount calculated by the measurement apparatus 100. . In addition, the user can recognize that a load is applied to a location that cannot be noticed by the strain (stress) distribution using CAE by confirming the color contour image based on the strain amount calculated by the measurement apparatus 100 by the user. can do.

<Supplement>
It goes without saying that the measuring apparatus according to the above embodiment is not limited to the above embodiment, and may be realized by other methods. Hereinafter, various modifications will be described.

  (1) In the above embodiment, the imaging unit 120 is an apparatus outside the measuring apparatus 100, but the measuring apparatus 100 may also include the imaging unit 120.

  (2) In the above embodiment, the display device 150 is a device outside the measurement device 100, but the measurement device 100 may include the display device 150.

  (3) In the above-described embodiment, when the measuring apparatus 100 outputs the distortion amount itself, the display device 150 that receives the distortion amount or the arithmetic device connected to the display device 150 receives the object based on the received distortion amount. It is desirable to have a function of generating 110 color contoured images.

  (4) In the above-described embodiment, an example in which the distortion amount is calculated every 1/60 seconds has been shown as a specific example. For example, it may be every 1/20 second or every 1/90 second.

  (5) In the above embodiment, the measurement unit 102 measures the light emission intensity (luminance) of each pixel from the captured image 130. Instead of this method, a light emission intensity (luminance) sensor is used. It may be measured.

  (6) In the above embodiment, as a method for the measurement device to calculate the distortion amount, the processor that functions as each functional unit constituting the measurement device 100 executes the distortion measurement program and the like to calculate the distortion amount. However, this may be realized by a logic circuit (hardware) or a dedicated circuit formed in an integrated circuit (IC (Integrated Circuit) chip, LSI (Large Scale Integration)) or the like in the device. These circuits may be realized by one or a plurality of integrated circuits, and the functions of the plurality of functional units described in the above embodiments may be realized by a single integrated circuit. An LSI may be called a VLSI, a super LSI, an ultra LSI, or the like depending on the degree of integration. That is, as shown in FIG. 7, each functional unit constituting the measuring apparatus 100 may be realized by a physical circuit. As shown in FIG. 7, the measuring apparatus 100 includes an acquisition circuit 101a, a measurement circuit 102a, an estimation circuit 103a, a calculation circuit 104a, an output circuit 105a, and a storage circuit 106a. It has the same function as each functional unit with the same name.

  The distortion measurement program may be recorded on a processor-readable recording medium. As the recording medium, a “non-temporary tangible medium” such as a tape, a disk, a card, a semiconductor memory, a programmable logic, and the like. A circuit or the like can be used. The distortion measurement program may be supplied to the processor via an arbitrary transmission medium (such as a communication network or a broadcast wave) that can transmit the distortion measurement program. The present invention can also be realized in the form of a data signal embedded in a carrier wave, in which the distortion measurement program is embodied by electronic transmission.

  The distortion measurement program can be implemented using, for example, a script language such as ActionScript or JavaScript (registered trademark), an object-oriented programming language such as Objective-C or Java (registered trademark), or a markup language such as HTML5. .

  (7) The configurations described in the above embodiment and each supplement may be combined as appropriate.

DESCRIPTION OF SYMBOLS 100 Measuring apparatus 101 Acquisition part 102 Measuring part 103 Estimation part 104 Calculation part 105 Output part 106 Storage part 110 Object 120 Imaging part 130 Captured image 150 Display apparatus

Claims (8)

An acquisition unit that acquires a captured image obtained by imaging a target to which a stress-luminescent material is applied;
From the captured image acquired by the acquisition unit, a measurement unit that measures a first emission intensity that is an emission intensity when the stress luminescent substance transitions from an excited state to a ground state;
Comparing the first emission intensity measured by the measurement unit with a second emission intensity that is an emission intensity when a stress-stimulated luminescent material applied with a uniform application thickness transitions from an excited state to a ground state; Based on the result of comparison, an estimation unit that estimates the application thickness of the stress-stimulated luminescent substance on the object;
Using the coating thickness estimated by the estimation unit, a calculation unit that calculates the emission intensity corrected to the emission intensity when the application thickness of the stress luminescent material is made uniform from the first emission intensity;
Including measuring device. The measurement unit measures, as the first emission intensity, the emission intensity when the stress-stimulated luminescent material that has been excited by being irradiated with light having a short wavelength transitions to a ground state when heated. The measuring apparatus according to claim 1, wherein: The measurement apparatus according to claim 1, wherein the acquisition unit acquires a captured image captured by continuing the exposure state while the stress-stimulated luminescent substance transitions from the excited state to the ground state. . The acquisition unit acquires a plurality of captured images sequentially captured while the stress-stimulated luminescent substance transitions from an excited state to a ground state,
4. The measurement unit according to claim 1, wherein the measurement unit measures the first light emission intensity by integrating light emission intensity calculated from each of the plurality of captured images sequentially captured. 5. The measuring device described in 1. In the case where the stress-stimulated luminescent material applied with a uniform coating thickness to a material having the same reflectance as the first emission intensity and the object transitions from an excited state to a ground state. 5. The second emission intensity, which is an emission intensity, is compared, and the application thickness of the stress luminescent substance on the object is estimated based on the comparison result. Measuring device. The estimation unit calculates a difference between the first emission intensity and the second emission intensity for each predetermined region of the object, and based on the calculated difference and the thickness of the uniform coating thickness The measuring apparatus according to claim 1, wherein a coating thickness of the stress luminescent substance is estimated. An acquisition step of acquiring a captured image obtained by imaging a target to which a stress luminescent material is applied;
A measurement step of measuring a first emission intensity that is an emission intensity when the stress luminescent substance transitions from an excited state to a ground state from the acquired captured image;
The measured first luminescence intensity is compared with the second luminescence intensity which is the luminescence intensity when the stress luminescent material applied with a uniform coating thickness transitions from the excited state to the ground state. Based on the estimation step of estimating the application thickness of the stress luminescent material on the object,
A calculation step of calculating a light emission intensity corrected to a light emission intensity when the application thickness of the stress luminescent material is made uniform from the first light emission intensity using the estimated application thickness;
Measuring method including On the computer,
An acquisition function for acquiring a captured image obtained by imaging an object to which a stress-luminescent material is applied;
A measurement function for measuring a first emission intensity, which is an emission intensity when the stress luminescent substance transitions from an excited state to a ground state, from the acquired captured image;
The measured first luminescence intensity is compared with the second luminescence intensity which is the luminescence intensity when the stress luminescent material applied with a uniform coating thickness transitions from the excited state to the ground state. Based on the estimation function to estimate the application thickness of the stress-stimulated luminescent material on the object,
A calculation function for calculating the emission intensity corrected to the emission intensity when the application thickness of the stress luminescent material is made uniform from the first emission intensity using the estimated application thickness;
A distortion measurement program that realizes