Measuring equipment

Abstract

To prevent dimension measurement of a measuring object from getting unmeasurable.SOLUTION: A measuring device 20 includes: a light emission part 374 for emitting light; an imaging part 375 for capturing an image for measurement containing a measuring object and a marker, the optical image displayed on a surface of an object other than the measuring object when the light emission part 374 applies light to the measuring object or the object other than the measuring object; and a processing circuit 42 for measuring a dimension of the measuring object based on the image for measurement captured by the imaging part 375.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a measuring device for measuring the size of a measurement object. [Background technology]

[0002] Patent Document 1 discloses a measuring device for measuring the brake lining of an electromagnetic brake. This measuring device captures an image including the brake lining and a marker that has been attached in advance to at least one of the brake lining and braking part of the electromagnetic brake, and measures the thickness of the brake lining based on the dimensions (number of pixels) of the marker, whose actual dimensions (hereinafter referred to as "actual dimensions") are known in the image. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-56391 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if the brake lining or braking part becomes dirty, at least a part of the marker may disappear or foreign matter may adhere to the marker. In this case, the marker may not be recognized in an image including the marker and the brake lining, and the thickness of the brake lining may not be measured. An object of the present invention is to prevent the size of the measurement object from becoming unmeasurable. [Means for solving the problem]

[0005] Measuring device for solving the above problems A first aspect of the present invention is a measuring device for measuring the size of a measurement object, which includes an imaging unit that captures a video including the measurement object and other components present in its vicinity, and a measurement unit that measures the size of the measurement object based on a measurement image, which is a frame of the video captured by the imaging unit, when at least one of the following is true: the imaging angle of the measurement object captured by the imaging unit is a value within a predetermined angle range, and the imaging distance between the imaging unit and the measurement object is a value within a predetermined distance range.

[0006] A second aspect of the measuring device for solving the above problem is a measuring device for measuring the size of a measurement object, comprising an imaging unit that captures a measurement image, which is a still image including the measurement object and other components present in its surroundings, and a measuring unit that measures the size of the measurement object based on the measurement image captured by the imaging unit, wherein the imaging unit captures the measurement image when at least one of the following is true: the imaging angle of the measurement object captured by the imaging unit is a value within a predetermined angle range, and the imaging distance between the imaging unit and the measurement object is a value within a predetermined distance range. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a side view that schematically shows a friction brake of a vehicle. [Figure 2] FIG. 2 is a plan view schematically showing a part of the friction brake. [Figure 3] FIG. 3 is a diagram showing a schematic configuration of the measurement device of the first embodiment. [Figure 4] FIG. 4 is a block diagram of the industrial endoscope in the measuring device. [Figure 5] FIG. 5 is a block diagram showing the functions of the measuring device. [Figure 6] In FIG. 6, (a) is a schematic diagram showing the positional relationship between the imaging unit and the imaging target when the imaging angle is 90°, and (b) is a schematic diagram showing the markers formed on the imaging target at that time. [Figure 7] In FIG. 7, (a) is a schematic diagram showing the positional relationship between the imaging unit and the imaging target when the imaging angle is not 90°, and (b) is a schematic diagram showing the markers formed on the imaging target at that time. [Figure 8] FIG. 8 is a schematic diagram showing an example of an image captured by the imaging section. [Figure 9] FIG. 9 is a schematic diagram showing an example of a measurement image captured by the imaging section. [Figure 10] FIG. 10 is a flowchart showing the flow of processing in the measurement device of the first embodiment. [Figure 11] FIG. 11 is a schematic diagram showing how the probe head of the industrial endoscope is inserted into the inspection window. [Figure 12] FIG. 12 is a flowchart showing the flow of processing in the measurement device of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] (First embodiment) An embodiment of the measuring device will be described below with reference to FIGS. <Vehicle friction brakes> Fig. 1 is a schematic diagram of a friction brake 10 provided on a vehicle. Fig. 2 is a plan view schematically showing a part of the friction brake 10 when the friction brake 10 is viewed from the direction indicated by the white arrow A11 shown in Fig. 1.

[0009] The friction brake 10 shown in Figures 1 and 2 is a disc brake. This friction brake 10 includes a caliper 11 supported on the vehicle body, two friction materials 12, and a disc rotor 13 that rotates integrally with the vehicle wheel. As shown in Figure 2, the friction material 12 is supported on a backing plate 14. The disc rotor 13 is interposed between the two friction materials 12.

[0010] 2, an inspection window 11a is provided in the caliper 11. When looking into the caliper 11 through the inspection window 11a, the disc rotor 13, the friction material 12, and the backing plate 14 can be seen.

[0011] <Measuring equipment> 3 is a schematic diagram showing the configuration of the measuring device 20 of this embodiment. The measuring device 20 is a device that measures the thickness D of the friction material 12 of the friction brake 10. That is, the measuring device 20 measures the thickness D, which is the size of the friction material 12 as the measurement target.

[0012] 3, the measuring device 20 includes an industrial endoscope 30, a computing device 40, a display device 51, and a notification device 53. FIG. As shown in FIG. 3, the industrial endoscope 30 includes a main body 31 , a connection cable 33 , a control unit 35 , and a probe 37 .

[0013] The probe 37 has a connection part 371, a movable part 372, and a probe head 373. The connection part 371 is provided at one end of the probe 37, and the probe head 373 is provided at the other end of the probe 37. The probe 37 is connected to the control unit 35 via the connection part 371. The movable part 372 is movable to change the orientation of the probe head 373, as shown in FIG. 3. In this embodiment, the movable part 372 can change the orientation of the probe head 373 by 90° or more.

[0014] The probe head 373 has a light-emitting unit 374 that emits light and an imaging unit 375 that captures an image of the measurement target. The light-emitting unit 374 emits parallel light. In this embodiment, the light-emitting unit 374 includes a semiconductor laser that emits laser light. The beam shape of the light emitted by the light-emitting unit 374 is a perfect circle. The light-emitting unit 374 irradiates the target with light, thereby displaying a marker MK, which is an image of light, on the surface of the target (see FIG. 8). When measuring the thickness D of the friction material 12, the target irradiated by the light-emitting unit 374 is the friction material 12 or another member (for example, the disc rotor 13 or the back plate 14) present around the friction material 12.

[0015] The imaging unit 375 forms an image by capturing an image of the marker MK and the periphery of the display position of the marker MK. When measuring the thickness D of the friction material 12, the imaging unit 375 captures a measurement image including the friction material 12 to be measured and the marker MK.

[0016] The main body 31 has a display screen 311 and an operation unit 312. The display screen 311 displays an image captured by the imaging unit 375 of the probe 37. The operation unit 312 has a plurality of buttons that are operated by an operator using the industrial endoscope 30. The operation unit 312 includes a light emission button 312a and an image capture button 312b as buttons. The light emission button 312a is a button that the operator operates to cause the light emission unit 374 to emit light or to stop the light emission of the light emission unit 374. The image capture button 312b is a button that the operator operates to cause the image capture unit 375 to capture an image.

[0017] The main body 31 may be a device dedicated to the industrial endoscope 30, or may be a general device. A typical general device may be a portable device such as a mobile phone. The buttons on the operation unit 312 are not limited to physical buttons. For example, the light emission button 312a and the image capture button 312b may be buttons displayed on a display device having a touch panel.

[0018] The main body 31 can communicate with the computing device 40. The communication between the main body 31 and the computing device 40 may be wired or wireless. For example, the main body 31 transmits a measurement image captured by the imaging unit 375 to the computing device 40.

[0019] The connection cable 33 connects the main body 31 and the control unit 35 . As shown in FIG. 4, the control unit 35 has an operation wheel 351 and an actuator 352. The actuator 352 is built into the control unit 35. When the actuator 352 is actuated, a movable part 372 of the probe 37 moves as shown in FIG. 3. The operation wheel 351 is operated by an operator when changing the orientation of the probe head 373. When the operator operates the operation wheel 351, the actuator 352 is actuated in response to the operation. This moves the movable part 372, changing the orientation of the probe head 373.

[0020] As shown in FIG. 3, computing device 40 includes communication device 41 and processing circuitry 42. The communication device 41 receives information transmitted from the industrial endoscope 30 and outputs it to the processing circuit 42 .

[0021] The processing circuit 42 has an execution unit 421 and a memory unit 422. For example, the execution unit 421 is a CPU. The memory unit 422 stores a control program that is executed by the execution unit 421 at a predetermined interval. In this embodiment, the memory unit 422 stores a control program for measuring the thickness D of the friction material 12 based on measurement images captured by the imaging unit 375 of the industrial endoscope 30.

[0022] The display device 51 displays the thickness D of the friction material 12 calculated by the calculation device 40. The notification device 53 notifies the worker of the content of the instruction from the calculation device 40. The notification device 53 may be a speaker that notifies the worker by voice, a lamp that notifies the worker by light, a screen that notifies the worker by display, or a vibration generating device that notifies the worker by vibration.

[0023] 5 is a block diagram showing the functions of the measurement device 20. When the execution unit 421 executes the above control program, the processing circuit 42 functions as an imaging angle estimation unit 71, an imaging distance estimation unit 75, and a measurement unit 80. The processing circuit 42 and the notification device 53 form an angle condition notification unit 72 and a distance condition notification unit 76.

[0024] The imaging angle estimation unit 71 estimates the imaging angle θ of the friction material 12 by the imaging unit 375 by analyzing the image captured by the imaging unit 375. As will be described in detail later, the imaging angle estimation unit 71 estimates the imaging angle θ based on the shape of the marker MK in the image.

[0025] When the imaging angle θ estimated by the imaging angle estimator 71 is within a predetermined angle range, the angle condition notifier 72 notifies the operator that it is possible to capture a measurement image, which is an image for measuring the thickness D of the friction material 12. If the imaging angle θ is significantly different from 90°, the distortion of the shape of the marker MK becomes significant, which may reduce the accuracy of the estimation calculation of the thickness D of the friction material 12 based on the measurement image. Therefore, a predetermined angle range is set as a criterion for determining whether the accuracy of the estimation calculation of the thickness D of the friction material 12 falls within an allowable range. In this embodiment, the predetermined angle range is a range of imaging angles θ that includes 90°.

[0026] The imaging distance estimation unit 75 analyzes the image captured by the imaging unit 375 to estimate the imaging distance L, which is the linear distance between the imaging unit 375 and the friction material 12. As will be described in detail later, the imaging distance estimation unit 75 estimates the imaging distance L based on the dimensions of objects other than the friction material 12 in the image.

[0027] The distance condition notification unit 76 notifies the worker that it is possible to capture a measurement image when the imaging distance L estimated by the imaging distance estimation unit 75 is within a predetermined distance range. The accuracy of the estimation calculation of the thickness D of the friction material 12 based on the measurement image may vary depending on the imaging distance L. Therefore, a predetermined distance range is set as a criterion for determining whether the accuracy of the estimation calculation of the thickness D of the friction material 12 falls within an allowable range.

[0028] The measuring unit 80 measures the thickness D of the friction material 12 based on the measurement image captured by the imaging unit 375. In this embodiment, the measuring unit 80 measures the thickness D of the friction material 12 based on the dimensions of the marker MK in the measurement image, as will be described in detail later.

[0029] <Estimation of imaging angle by imaging angle estimation unit> The estimation process of the imaging angle θ by the imaging angle estimation unit 71 will be described with reference to Fig. 6 and Fig. 7. In Fig. 6, (a) is a schematic diagram showing the positional relationship between the imaging target 100 and the probe head 373 when the imaging angle θ is 90°, and (b) is a schematic diagram showing the marker MK formed on the imaging target 100 at that time. In Fig. 7, (a) is a schematic diagram showing the positional relationship between the imaging target 100 and the probe head 373 when the imaging angle θ is not 90°, and (b) is a schematic diagram showing the marker MK formed on the imaging target 100 at that time. Note that the two-dot chain line in Fig. 6(a) and Fig. 7(a) indicates the optical axis of the light emitting unit 374.

[0030] As shown in Figures 6(a) and (b), when the imaging angle θ is 90°, the marker MK formed on the imaging target 100 has a perfect circular shape. In Figure 6(b), the left-right direction in the figure is defined as the "first direction X1," and the direction perpendicular to the first direction X1 is defined as the second direction X2. In this case, the dimension F1 of the marker MK in the first direction X1 is equal to the dimension F2 of the marker MK in the second direction X2. Here, "the dimension F1 is equal to the dimension F2" means that they are substantially the same, and some degree of error is allowed.

[0031] 7(a) and 7(b), when the imaging angle θ is not 90°, the marker MK formed on the imaging target 100 has an elliptical shape. That is, the dimension F1 of the marker MK in the first direction X1 is longer than the dimension F2 of the marker MK in the second direction X2.

[0032] If the ratio of the dimension F2 in the second direction X2 to the dimension F1 in the first direction X1 is defined as the aspect ratio α, then when the imaging angle θ is 90°, the aspect ratio α will be 1. If the imaging angle θ is not 90°, the aspect ratio α will not be 1. Thus, the more the imaging angle θ deviates from 90°, the more the aspect ratio α deviates from 1.

[0033] Therefore, the imaging angle estimation unit 71 estimates the imaging angle θ based on the shape in the image IMG of an object whose actual shape is known. For example, the imaging angle estimation unit 71 estimates the imaging angle θ so that the imaging angle θ approaches 90° as the aspect ratio α of the marker MK approaches 1. In other words, the imaging angle estimation unit 71 estimates the imaging angle θ so that the imaging angle θ deviates from 90° as the aspect ratio α deviates from 1 more.

[0034] <Estimation of imaging distance by imaging distance estimation unit> The estimation process of the imaging distance L by the imaging distance estimation unit 75 will be described with reference to Fig. 8. Fig. 8 is a diagram showing an image IMG including the friction material 12 and other members present in the vicinity thereof, captured by the imaging unit 375. In the image IMG shown in Fig. 8, a marker MK is displayed on the surface of the disc rotor 13 adjacent to the friction material 12.

[0035] The light emitted by the light-emitting portion 374 is parallel light. Therefore, the dimensions of the marker MK displayed on the surface of the disc rotor 13 do not change depending on the imaging distance L. In other words, the dimensions of the marker MK are substantially the same as the design values ​​of the dimensions of the marker MK in the light-emitting portion 374. Furthermore, in the friction brake 10, although the friction material 12 wears, the disc rotor 13 and backing plate 14 hardly wear. Therefore, the thicknesses of the disc rotor 13 and backing plate 14 hardly change from when they were new. In other words, the thicknesses of the disc rotor 13 and backing plate 14 are substantially the same as the design values.

[0036] 8, the dimension (number of pixels) F3 of the marker MK in the left-right direction in the drawing, the dimension (number of pixels) F41 of the disc rotor 13 in the image IMG in the left-right direction in the drawing, and the dimension (number of pixels) F42 of the back plate 14 in the image IMG in the left-right direction in the drawing vary depending on the imaging distance L. Specifically, the dimensions F3, F41, and F42 become smaller as the imaging distance L becomes longer.

[0037] Therefore, the imaging distance estimation unit 75 estimates the imaging distance L based on the relationship between the dimensions (number of pixels) in the image IMG of an object whose actual shape is known and the known actual dimensions of that object. For example, the imaging distance estimation unit 75 can estimate the imaging distance L based on the relationship between the dimension F3 of the marker MK in the image IMG, the dimension F41 of the disk rotor 13 in the image IMG, or the dimension F42 of the back plate 14 in the image IMG and the corresponding design values. In this embodiment, when the ratio of the dimension F3 of the marker MK in the image IMG to the design value of the dimension of the marker MK in the light-emitting unit 374 is defined as a distance ratio β, the imaging distance estimation unit 75 estimates the imaging distance L so that the smaller the distance ratio β, the longer the imaging distance L.

[0038] <Measurement of friction material thickness using the measuring unit> The measurement process of the thickness D of the friction material 12 by the measurement unit 80 will be described with reference to Fig. 9. Fig. 9 is a diagram showing a measurement image IMG1 including the friction material 12, other members positioned around the friction material 12, and a marker MK.

[0039] The measurement unit 80 performs known image analysis on the measurement image IMG1 to detect a first boundary B1, which is the boundary between the friction material 12 and the disc rotor 13, and a second boundary B2, which is the boundary between the friction material 12 and the backing plate 14. Next, the measurement unit 80 measures an in-image distance F5, which is the distance between the first boundary B1 and the second boundary B2 in the measurement image IMG1, and measures an in-image marker dimension F6, which is the dimension of the marker MK in the measurement image IMG1. The in-image distance F5 is the dimension of the friction material 12 in the left-right direction in the figure in the measurement image IMG1.

[0040] The measuring unit 80 knows the actual dimension Gmk of the marker MK, and can therefore measure the thickness D of the friction material 12 based on the in-image distance F5 and the in-image marker dimension F6. For example, the measuring unit 80 can calculate the thickness D using the following relational expression (Equation 1). As a result, the measuring unit 80 calculates the thickness D of the friction material 12 so that the thickness increases as the ratio of the in-image distance F5 to the in-image marker dimension F6 increases.

[0041]

number

[0042] <Measurement method> 10 and 11, a method for measuring the thickness D of the friction material 12 using the measuring device 20 will be described. The measuring method of this embodiment is a method for measuring the thickness D of the friction material 12 using the measuring device 20. FIG. 10 is a flowchart showing the processing flow in the measuring device 20. FIG. 11 is a schematic diagram showing how the probe head 373 is inserted into the inspection window 11a of the caliper 11.

[0043] 11, the worker inserts the probe head 373 of the industrial endoscope 30 into the inspection window 11a of the caliper 11. This causes the imaging unit 375 and the light emitting unit 374 to be inserted into the inspection window 11a. This process corresponds to the "insertion step."

[0044] More specifically, the worker inserts the probe head 373 toward the friction brake 10 through a gap formed in the wheel of the vehicle. In this state, the worker operates the operating wheel 351 of the control unit 35 of the industrial endoscope 30 to change the imaging range of the imaging unit 375 and check the position of the inspection window 11a on the image IMG displayed on the display screen 311. Then, while looking at the image IMG displayed on the display screen 311, the worker inserts the probe head 373 into the inspection window 11a.

[0045] When the worker presses the light-emitting button 312a on the main body 31, in step S11 of FIG. 10, the execution unit 421 of the computing device 40 determines that the worker has issued an instruction to cause the light-emitting unit 374 to emit light (S11: YES), and proceeds to processing in step S13. In step S13, the execution unit 421 causes the light-emitting unit 374 to start emitting light. As a result, a marker MK is displayed on the surface of the friction material 12 or the disc rotor 13, as shown in FIG. 9. At this time, the marker MK may also be displayed on the surface of the backing plate 14. Step S13 corresponds to a "marker display step" of displaying the marker MK on the surface of the friction material 12, the disc rotor 13, or the backing plate 14. Thereafter, the execution unit 421 proceeds to processing in step S15.

[0046] If the execution unit 421 determines in step S11 that the operator has not issued a light emission instruction (S11: NO), it ends the current processing. In step S15, the execution unit 421 estimates the imaging angle θ by functioning as the imaging angle estimation unit 71. More specifically, the image IMG captured by the imaging unit 375 is transmitted from the industrial endoscope 30 to the calculation device 40. The execution unit 421 estimates the imaging angle θ based on the received image IMG.

[0047] In the following step S17, the execution unit 421 estimates the imaging distance L by functioning as the imaging distance estimation unit 75. In detail, the execution unit 421 estimates the imaging distance L based on the image IMG transmitted from the industrial endoscope 30 to the calculation device 40.

[0048] In step S19, the execution unit 421 determines whether the imaging angle θ estimated in step S15 is a value within a predetermined angle range. If the imaging angle θ is a value outside the predetermined angle range (S19: NO), the execution unit 421 ends the current process. On the other hand, if the imaging angle θ is a value within the predetermined angle range (S19: YES), the execution unit 421 proceeds to the process of step S21.

[0049] In step S21, the execution unit 421 notifies the worker that the imaging angle θ is a value within a predetermined angle range by the notification device 53. That is, the processing of step S21 is executed by the execution unit 421 and the notification device 53 functioning as the angle condition notification unit 72.

[0050] In step S23, the execution unit 421 determines whether the imaging distance L estimated in step S17 is a value within a predetermined distance range. If the imaging distance L is a value outside the predetermined distance range (S23: NO), the execution unit 421 ends the current processing. On the other hand, if the imaging distance L is a value within the predetermined distance range (S23: YES), the execution unit 421 proceeds to processing in step S25.

[0051] In step S25, the execution unit 421 notifies the worker that the imaging distance L is a value within a predetermined distance range by the notification device 53. That is, the processing of step S25 is executed by the execution unit 421 and the notification device 53 functioning as the distance condition notification unit 76.

[0052] In this embodiment, it is determined that the imaging conditions for the measurement image IMG1 are met when both the imaging angle θ is a value within a predetermined angle range and the imaging distance L is a value within a predetermined distance range. When the imaging conditions are met in this way, the execution unit 421 proceeds to the processing of step S26.

[0053] In the following step S26, the execution unit 421 determines whether or not the operator has issued an image capture instruction to cause the image capture unit 375 to capture a measurement image IMG1. Specifically, the execution unit 421 determines whether or not the operator has operated the image capture button 312b. If the execution unit 421 determines that the operator has not issued an image capture instruction (S26: NO), it ends the current process, and if the execution unit 421 determines that the operator has issued an image capture instruction (S26: YES), it proceeds to the process of step S27.

[0054] In step S27, the execution unit 421 captures the measurement image IMG1 using the imaging unit 375. Step S27 corresponds to an "imaging step" of capturing the measurement image IMG1 including the marker MK and the friction material 12.

[0055] In the following step S29, the execution unit 421 functions as the measurement unit 80 to measure the thickness D of the friction material 12. Step S29 corresponds to a "measurement step" of measuring the thickness D of the friction material 12 based on the measurement image IMG1.

[0056] Finally, in step S31, the execution unit 421 notifies the worker of the thickness D of the friction material 12 measured in step S29. For example, the execution unit 421 causes the display device 51 to display the thickness D of the friction material 12. Then, the execution unit 421 ends the current processing.

[0057] <Effects of this embodiment> (1-1) In this embodiment, the thickness D of the friction material 12 is measured based on the size of the marker MK in the measurement image IMG1.

[0058] The markers MK are light images displayed on the surfaces of the friction material 12, the disc rotor 13, or the backing plate 14 by the light-emitting unit 374 irradiating the friction material 12 or the disc rotor 13 with light. In other words, the markers MK are not previously attached to the friction material 12, the disc rotor 13, or the backing plate 14. Therefore, even if the friction material 12, the disc rotor 13, or the backing plate 14 becomes dirty due to use of the friction brake 10, the markers MK can be identified in the measurement image IMG1 regardless of the degree of dirt, and the thickness D of the friction material 12 can be measured based on the size of the markers MK in the measurement image IMG1.

[0059] (1-2) In this embodiment, the measurement image IMG1 is captured under the condition that the imaging angle θ is within a predetermined angle range. This allows the thickness D of the friction material 12 to be measured with high accuracy using the measurement image IMG1 whose imaging angle θ is not significantly different from 90°.

[0060] (1-3) In this embodiment, the measurement image IMG1 is captured on the condition that the imaging distance L is within a predetermined distance range. This allows the thickness D of the friction material 12 to be measured with high accuracy using the measurement image IMG1 when the imaging distance L is within the predetermined distance range.

[0061] (1-4) In this embodiment, the thickness D of the friction material 12, the imaging angle θ, and the imaging distance L are estimated based on the markers MK in the image captured by the imaging unit 375. Therefore, it is preferable that the process of identifying the markers MK in the image captured by the imaging unit 375 (hereinafter referred to as the “marker identification process”) be simple.

[0062] In this regard, in the present embodiment, both the light emitting unit 374 and the imaging unit 375 are provided in the probe head 373, and the relationship between the direction of light irradiation by the light emitting unit 374 and the direction of imaging by the imaging unit 375 is maintained. Therefore, the marker MK is displayed in a predetermined area of ​​the image captured by the imaging unit 375. This makes it possible to set a target range for the marker identification process in the image captured by the imaging unit 375, and ultimately reduces the amount of processing required for the marker identification process.

[0063] In this embodiment, the shape of the marker MK is a perfect circle. In this way, by designing the shape of the marker MK in the light-emitting unit 374 to be easily recognizable in the measurement image IMG1, the processing contents of the marker identification process can be simplified.

[0064] (Second embodiment) A second embodiment of the measuring device 20 and measuring method will be described with reference to Fig. 12. In the second embodiment, differences from the first embodiment will be mainly described, and the same reference numerals will be used to designate configurations and functions that are substantially the same as those in the first embodiment, and duplicated explanations will be omitted.

[0065] <Industrial endoscope> In this embodiment, the imaging unit 375 of the industrial endoscope 30 starts capturing a moving image when the imaging button 312b of the main body 31 is operated. Then, frames constituting the moving image are transmitted to the computing device 40 one by one.

[0066] <Measurement method> The measurement method of this embodiment will be described with reference to Fig. 12. Fig. 12 is a flowchart showing the flow of processing in the measurement device 20.

[0067] As in the first embodiment, the worker inserts the probe head 373 of the industrial endoscope 30 into the inspection window 11a of the caliper 11 (see FIG. 11). This process corresponds to the "insertion step."

[0068] When the worker presses the light-emitting button 312a on the main body 31, in step S51 of FIG. 12, the execution unit 421 of the computing device 40 determines that the worker has issued a light-emitting instruction (S51: YES), and proceeds to processing in step S53. In step S53, the execution unit 421 starts emitting light from the light-emitting unit 374. In this embodiment, step S53 corresponds to a "marker display step." Thereafter, the execution unit 421 proceeds to processing in step S54.

[0069] If the execution unit 421 determines in step S51 that the operator has not issued a light emission instruction (S51: NO), it ends the current processing. In step S54, the execution unit 421 determines whether or not the operator has issued an image capture instruction to cause the image capture unit 375 to capture a measurement image IMG1. Specifically, the execution unit 421 determines whether or not the operator has operated the image capture button 312b. If the execution unit 421 determines that the operator has not issued an image capture instruction (S54: NO), it ends the current process, and if the execution unit 421 determines that the operator has issued an image capture instruction (S54: YES), it proceeds to the process of step S55.

[0070] In step S55, the execution unit 421 causes the imaging unit 375 to start capturing a moving image. Then, in step S57, the execution unit 421, similar to step S15 in the first embodiment, estimates the imaging angle θ by functioning as the imaging angle estimation unit 71. In step S59, the execution unit 421, similar to step S17 in the first embodiment, estimates the imaging distance L by functioning as the imaging distance estimation unit 75.

[0071] In step S61, the execution unit 421 determines whether the imaging angle θ estimated in step S57 is a value within a predetermined angle range, as in step S19 in the first embodiment. If the imaging angle θ is a value outside the predetermined angle range (S61: NO), the execution unit 421 ends the current process. On the other hand, if the imaging angle θ is a value within the predetermined angle range (S61: YES), the execution unit 421 proceeds to the process of step S63.

[0072] In step S63, the execution unit 421 determines whether the imaging distance L estimated in step S59 is a value within a predetermined distance range, similar to step S23 in the first embodiment. If the imaging distance L is a value outside the predetermined distance range (S63: NO), the execution unit 421 ends the current process. On the other hand, if the imaging distance L is a value within the predetermined distance range (S63: YES), the execution unit 421 proceeds to the process of step S65.

[0073] In step S65, the execution unit 421 acquires, as the measurement image IMG1, a frame of the moving image captured by the imaging unit 375. As a result, a frame in which the imaging angle θ is a value within a predetermined angle range and the imaging distance L is a value within a predetermined distance range is acquired as the measurement image IMG1.

[0074] In step S67, the execution unit 421 notifies the worker that capturing of the measurement image IMG1 has been completed by the notification device 53. The processing of step S67 is executed by the execution unit 421 and the notification device 53 functioning as the angle condition notification unit 72 and the distance condition notification unit 76.

[0075] In step S69, the execution unit 421 functions as the measurement unit 80 in the same manner as in step S29 of the first embodiment, thereby measuring the thickness D of the friction material 12 based on the measurement image IMG1 acquired in step S65. In this embodiment, step S69 corresponds to the "measurement step."

[0076] Finally, in step S71, the execution unit 421 notifies the operator of the thickness D of the friction material 12 measured in step S69, in the same manner as in step S31 of the first embodiment. Then, the execution unit 421 ends the current processing.

[0077] <Effects of this embodiment> According to this embodiment, in addition to the effects (1-1) to (1-4) of the first embodiment, the following effects can be obtained.

[0078] (2-1) In this embodiment, when the imaging unit 375 starts capturing a video, frames of the video are sequentially transmitted to the computing device 40. Therefore, the computing device 40 can individually analyze multiple frames constituting the video. That is, the computing device 40 can determine whether the video contains a frame that satisfies both the conditions that the imaging angle θ is within a predetermined angle range (hereinafter referred to as the “imaging angle condition”) and the imaging distance L is within a predetermined distance range (hereinafter referred to as the “imaging distance condition”). If it is determined that such a frame is included in the video, the frame is acquired as a measurement image IMG1, and the thickness D of the friction material 12 is measured based on the measurement image IMG1. That is, it is possible to eliminate the need for the operator to operate the imaging button 312b to acquire the measurement image IMG1 only after both the conditions that the imaging angle θ is within a predetermined angle range and the imaging distance L is within a predetermined distance range are satisfied.

[0079] (Example of change) The above-described embodiments can be modified as follows: The above-described embodiments and the following modifications can be combined with each other to the extent that no technical contradiction occurs.

[0080] In the above embodiments, the imaging distance L is estimated based on the size of the marker MK in the measurement image IMG1, but the imaging distance L may also be estimated based on the size of an object whose size is unlikely to change over time and whose actual dimensions are known in the measurement image IMG1. For example, the imaging distance L may also be estimated based on the size of the disc rotor 13 or the size of the back plate 14.

[0081] In the first embodiment, when the imaging angle condition and the imaging distance condition are both met, the worker is notified that the conditions have been met. However, when both the imaging angle condition and the imaging distance condition are met, the operator may be notified that the imaging conditions for the measurement image IMG1 are met.

[0082] Furthermore, it is not necessary to set either the imaging angle condition or the imaging distance condition. Furthermore, it is not necessary to set both the imaging angle condition and the imaging distance condition. In the second embodiment, when both the imaging angle condition and the imaging distance condition are met, the operator is notified that the measurement image IMG1 has been captured.

[0083] However, when the measurement image IMG1 is captured, the thickness D of the friction material 12 is measured based on the measurement image IMG1. Therefore, the worker may be notified that the thickness D of the friction material 12 has been measured. For example, the measured thickness D of the friction material 12 may be displayed on the display device 51. In this case, the worker can recognize that the thickness measurement has been completed when the thickness D is displayed on the display device 51.

[0084] Furthermore, it is not necessary to set either the imaging angle condition or the imaging distance condition. For example, if a frame that satisfies the imaging angle condition exists among the multiple frames that make up the moving image captured by the imaging unit 375, that frame may be acquired as the measurement image IMG1 even if that frame does not satisfy the imaging distance condition. Specifically, in the processing flow shown in FIG. 12, the processing of step S63 may be omitted.

[0085] Furthermore, if a frame that satisfies the imaging distance condition exists among the multiple frames that make up the moving image captured by the imaging unit 375, the frame may be acquired as the measurement image IMG1 even if the frame does not satisfy the imaging angle condition. Specifically, in the processing flow shown in FIG. 12, the processing of step S61 may be omitted.

[0086] Furthermore, it is not necessary to set both the imaging angle condition and the imaging distance condition. In the measurement image IMG1, if the imaging angle condition is not satisfied, the shape of the marker MK may be distorted. Therefore, if the imaging conditions for the measurement image IMG1 do not include the imaging angle condition, it is recommended to correct the in-image marker dimension F6, which is the dimension of the marker MK in the measurement image IMG1, according to the imaging angle θ. For example, the product of the in-image marker dimension F6 and the aspect ratio α can be used as the corrected in-image marker dimension F6.

[0087] The light emitting unit 374 does not have to be a semiconductor laser as long as it can emit parallel light and can display the marker MK on the surface of the friction material 12 or on the surface of another member located in the vicinity of the friction material 12.

[0088] In the above-described embodiments, the image capturing unit 375 and the light emitting unit 374 are unitized, but the light emitting unit 374 and the image capturing unit 375 do not have to be unitized. For example, the light emitting unit 374 and the image capturing unit 375 may be provided separately in the probe head 373, or the light emitting unit 374 may be provided separately from the probe head 373, or the image capturing unit 375 may be provided separately from the probe head 373.

[0089] In the above-described embodiments, the imaging distance L is estimated based on the dimensions in the image IMG of the marker MK whose actual dimensions are known. However, the imaging distance L may also be estimated using the principle of triangulation, or based on the time it takes for the laser light reflected from the measurement object to be detected, or based on the time it takes for the ultrasound wave reflected from the measurement object to be detected.

[0090] In the first embodiment, the notification device 53 provided separately from the industrial endoscope 30 notifies the worker that the imaging angle condition and the imaging distance condition are satisfied. However, the notification device 53 may be provided separately from the industrial endoscope 30 to notify the worker.

[0091] For example, the display screen 311 provided on the main body 31 of the industrial endoscope 30 may display that the imaging angle condition and the imaging distance condition are satisfied. Furthermore, a device for vibrating the main body 31 may be provided inside the main body 31 so that the vibration of the main body 31 notifies the operator that the imaging angle condition and the imaging distance condition are satisfied.

[0092] In the second embodiment, the worker is notified that the measurement image IMG1 has been acquired using an alarm device 53 provided separately from the industrial endoscope 30, but the worker may also be notified using an alarm means other than the alarm device 53.

[0093] For example, the fact that the measurement image IMG1 has been acquired may be displayed on a display screen 311 provided on the main body 31 of the industrial endoscope 30. Also, a device for vibrating the main body 31 may be provided inside the main body 31, and the fact that the measurement image IMG1 has been acquired may be notified to the worker by the vibration of the main body 31.

[0094] In the above embodiments, the thickness D of the friction material 12 is displayed on the display device 51 provided separately from the industrial endoscope 30, but the thickness D may be notified to the worker using a notification means other than the display device 51. For example, the thickness D of the friction material 12 may be displayed on a display screen 311 provided on the main body 31 of the industrial endoscope 30. Also, a device that generates sound may be provided on the main body 31 or separately from the main body 31, and the thickness D of the friction material 12 may be notified to the worker by sound.

[0095] In the above embodiments, the measuring device 20 is illustrated as including the industrial endoscope 30, the computing device 40, the display device 51, and the alarm device 53. However, at least some of the functions of the computing device 40, the display device 51, and the alarm device 53 may be integrated into the industrial endoscope 30. For example, the thickness D of the friction material 12 may be displayed on the display screen 311. The content of the notification to the worker may be displayed on the display screen 311, or a speaker may be provided in the industrial endoscope 30 to provide the content of the notification to the worker by voice, or a lamp may be provided in the industrial endoscope 30 to provide the content of the notification to the worker by light. Alternatively, a circuit equivalent to the processing circuit 42 may be provided in the industrial endoscope 30, and the thickness D of the friction material 12 may be measured by this circuit. In this case, the control program and the thickness D of the friction material 12 may be stored in a wirelessly connected storage device.

[0096] In the above-described embodiments, the measurement image IMG1 is acquired by inserting the imaging unit 375 into the inspection window 11a of the caliper 11. That is, in the above-described embodiments, the thickness D of the portion of the friction material 12 exposed through the inspection window 11a is measured. However, the measurement image IMG1 may be acquired with the imaging unit 375 approaching the friction material 12 from a location other than the inspection window 11a. For example, the measurement image IMG1 may be acquired with the imaging unit 375 approaching the lateral or lower end of the friction material 12 from the side or below the caliper 11. This makes it possible to measure the thickness D of the friction material 12 provided in a caliper that does not have an inspection window.

[0097] Alternatively, a measurement image (first measurement image) including a first end portion of the friction material 12 may be captured, and a measurement image (second measurement image) including a second end portion different from the first end portion may be captured. In this way, the degree of uneven wear of the friction material 12 can be estimated by comparing the thickness measured based on the first measurement image with the thickness measured based on the second measurement image.

[0098] The processing circuitry 42 may be configured as one or more processors that operate according to a computer program, one or more dedicated hardware circuits such as dedicated hardware that executes at least some of the various processes, or a circuit including a combination of these. Dedicated hardware may include, for example, an application-specific integrated circuit (ASIC).

[0099] The measuring device may be embodied as a measuring device that measures a member other than the friction material 12. The measurement object other than the friction material 12 may be a member whose size changes with use.

[0100] Next, the technical ideas that can be understood from the above-described embodiments and modifications will be described. (i) A measuring device in which the light-emitting unit emits laser light. Laser light has high directivity, so it can measure the size of the measurement object with high accuracy.

[0101] (b) The measuring device, wherein the beam shape of the laser light emitted by the light emitting unit is circular. By making the beam shape in this way a shape that makes it easy to recognize the marker MK in the image captured by the imaging unit 375, the processing contents of the marker identification process can be simplified.

[0102] (c) The measurement device, wherein the imaging unit captures the measurement image when the imaging angle estimated by the imaging angle estimation unit is within the angle range. (d) the imaging unit captures a video; The measurement unit acquires, as the measurement image, from among the frames of the video captured by the imaging unit, the frames in which the imaging angle estimated by the imaging angle estimation unit is a value within the angle range.

[0103] (e) A measurement device comprising an angle condition notification unit that notifies that the measurement image can be captured or that the measurement image has been captured when the imaging angle estimated by the imaging angle estimation unit is within the angle range.

[0104] (f) The measurement device, wherein the imaging unit captures the measurement image when the imaging distance estimated by the imaging distance estimation unit is within the distance range. (g) the imaging unit captures a video; The measurement unit acquires, as the measurement image, from among the frames of the video captured by the imaging unit, the frames in which the imaging distance estimated by the imaging distance estimation unit is a value within the distance range.

[0105] (h) A measurement device comprising a distance condition notification unit that notifies that the measurement image can be captured or that the measurement image has been captured when the imaging distance estimated by the imaging distance estimation unit is within the distance range.

[0106] (i) the imaging unit is provided in an industrial endoscope, The light emitting unit is provided at the tip of the probe of the industrial endoscope. (J) A measurement method for measuring the size of a measurement object using the above-mentioned measurement device, a marker display step of displaying the marker, which is a light image, on a surface of the measurement target or an object other than the measurement target by the light emitting unit; an imaging step of imaging the measurement image including the marker displayed on the surface in the marker display step and the measurement object by the imaging unit; a measuring step of measuring a size of the measurement object by the measuring unit based on the measurement image captured in the imaging step.

[0107] (k) The measurement object is a friction material of a disc brake, A measuring method including an insertion step of inserting the imaging unit and the light emitting unit into an inspection window formed in a caliper of the disc brake. [Explanation of symbols]

[0108] 10...Friction brake (disc brake) 12...Friction material (example of measurement object) 11...Caliper 11a...Inspection window 13...Disc rotor 14...Back plate 20...Measuring device 30...Industrial endoscope 37...Probe 373...Probe head (tip of the probe) 374...Light-emitting part 375...imaging unit 42...Processing circuit 71...imaging angle estimation unit 72...Angle condition notification unit 75...imaging distance estimation unit 76...Distance condition notification unit 80...Measuring part IMG...Image IMG1...Measurement image MK...Marker

Claims

1. A measuring device for measuring the thickness of a friction material of a friction brake installed on a vehicle as the size of the measurement object, an imaging unit that captures a moving image including the measurement object and other components present around the measurement object; and a measurement unit that measures the size of the measurement object based on a measurement image, which is a frame of the video captured by the imaging unit, when the imaging angle of the measurement object by the imaging unit is within a predetermined angle range.

2. The measuring device notifies at least one of the following: when the video captured by the imaging unit includes the measurement image, the measurement image has been captured; and when the size of the measurement object has been measured by the measuring unit, the size of the measurement object has been measured. The measuring device according to claim 1 .

3. A measuring device for measuring the thickness of a friction material of a friction brake installed on a vehicle as the size of the measurement object, an imaging unit that captures a measurement image, which is a still image including the measurement object and other components present around the measurement object; a measuring unit that measures the size of the measurement object based on the measurement image captured by the imaging unit, The measuring device is characterized in that the imaging unit captures the measurement image when the imaging angle of the measurement object by the imaging unit is a value within a predetermined angle range.

4. The measuring device notifies at least one of the fact that the measurement image has been captured when the measurement image has been captured by the imaging unit, and the fact that the size of the measurement object has been measured when the measurement unit has measured the size of the measurement object. The measuring device according to claim 3 .

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