Tire groove measuring device, tire groove measuring system, and tire groove measuring method

Abstract

A hand-held tire groove measuring device 1 comprises a range sensor 21 that detects the distance between a tire 30 and the tire groove measuring device 1 and a processing device 10 that generates, on the basis of output data of the range sensor 21 , contour shape data 50 indicating a contour shape of the tire 30. The processing device 10 detects a plurality of main grooves 41 on the basis of the contour shape data 50, deletes data corresponding to portions of the plurality of main grooves 41 from the contour shape data 50, interpolates the deleted portions of the plurality of main grooves 41 for the contour shape data 50 from which the data on the portions of the plurality of main grooves 41 has been deleted, generates trajectory data 51 indicating a trajectory of a movement of the tire groove measuring device 1, compares the trajectory data 51 and reference shape data 52 prepared in advance and indicating a contour shape of the tire 30 serving as a reference with each other to generate camera shake component data 53 indicating a camera shake component, and uses the camera shake component data 53 to correct the contour shape data 50 before the deletion of the data on the portions of the plurality of main grooves 41.

Description

[Technical Field]

[0001] The present invention relates to a tire groove measuring device, a tire groove measuring system, and a tire groove measuring method. [Background technology]

[0002] Tires mounted on automobiles and other vehicles have grooves in their treads. As the vehicle travels, the tires wear down and the groove depth decreases, making it necessary to measure the groove depth and manage the condition of the tires.

[0003] Patent Document 1 discloses a measuring device that measures the grooves in a tire tread. The measuring device is fixed to the ground as a car stopper for a parking space. Patent Document 1 discloses a technique for measuring the tire grooves by parking a vehicle so that the tire comes into contact with the measuring device, which is a car stopper. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-086293 Summary of the Invention [Problem to be solved by the invention]

[0005] The measurement device in Patent Document 1 is fixed to the ground, so groove measurements can only be performed at the location where the measurement device is installed. Furthermore, the vehicle must be moved so that the tire is positioned at a predetermined position at a predetermined angle. Furthermore, Patent Document 1 does not disclose how to process the output data from the laser displacement sensor that measures tire grooves to manage the grooves.

[0006] There is a demand for improving user convenience in measuring tire grooves. [Means for solving the problem]

[0007] A tire groove measuring device according to one embodiment of the present invention is a handheld tire groove measuring device that a user moves along the tread of a tire to be measured and measures the grooves in the tread of the tire. The device comprises a distance measurement sensor that detects the distance between the tire and the tire groove measuring device, and a processing device that generates contour shape data that indicates the contour shape of the tire based on output data from the distance measurement sensor. The tire tread has main grooves that have slip signs. The processing device detects a plurality of main grooves based on the contour shape data, deletes data for the plurality of main groove portions from the contour shape data, interpolates the deleted portions of the plurality of main grooves from the contour shape data from which the data for the plurality of main groove portions has been deleted, generates trajectory data that indicates the trajectory of the movement of the tire groove measuring device, compares the trajectory data with reference shape data that indicates the contour shape of a reference tire prepared in advance, generates hand vibration component data that indicates hand vibration components, and uses the hand vibration component data to correct the contour shape data before the data for the plurality of main groove portions was deleted.

[0008] A tire groove measurement system according to one embodiment of the present invention is a tire groove measurement system that measures grooves in the tread of a tire using a handheld tire groove measurement device that a user moves along the tread of the tire to be measured. The system includes a distance measurement sensor that is provided in the tire groove measurement device and detects the distance between the tire and the tire groove measurement device, and a processing device that generates contour shape data that indicates the contour shape of the tire based on output data from the distance measurement sensor. The tire tread has main grooves that have slip signs. The processing device detects a plurality of main grooves based on the contour shape data, deletes data for portions of the plurality of main grooves from the contour shape data, interpolates the deleted portions of the plurality of main grooves from the contour shape data from which the data for the portions of the plurality of main grooves has been deleted, generates trajectory data that indicates the trajectory of movement of the tire groove measurement device, compares the trajectory data with reference shape data that indicates the contour shape of a reference tire prepared in advance, generates hand vibration component data that indicates hand vibration components, and uses the hand vibration component data to correct the contour shape data before the data for the portions of the plurality of main grooves has been deleted.

[0009] A tire groove measurement method according to one embodiment of the present invention is a tire groove measurement method in which a user uses a handheld tire groove measurement device that is moved along the tread of a tire to be measured to measure grooves in the tread of the tire, the tire tread having main grooves with slip signs. The tire groove measurement method includes: detecting a distance between the tire and the tire groove measurement device using a distance measurement sensor; generating contour shape data that indicates a contour shape of the tire based on output data of the distance measurement sensor; detecting a plurality of main grooves based on the contour shape data; deleting data for the plurality of main groove portions from the contour shape data; interpolating the deleted portions of the plurality of main grooves from the contour shape data from which the data for the plurality of main groove portions has been deleted to generate trajectory data that indicates a trajectory of movement of the tire groove measurement device; comparing the trajectory data with reference shape data that indicates the contour shape of a reference tire prepared in advance to generate hand vibration component data that indicates a hand vibration component; and correcting the contour shape data before deleting the data for the plurality of main groove portions using the hand vibration component data. [Effects of the Invention]

[0010] With a handheld tire groove measuring device, the user holds the tire groove measuring device in their hand and moves it around when measuring the tire, so there may be a discrepancy between the contour shape data obtained from the output data of the distance measurement sensor and the actual contour shape of the tire.

[0011] According to one embodiment of the present invention, trajectory data indicating the trajectory of movement of the tire groove measurement device is generated based on contour shape data obtained from output data of the distance measurement sensor, and the trajectory data is used to generate camera shake component data. By correcting the contour shape data using the generated camera shake component data, it is possible to reduce the discrepancy between the contour shape data and the actual tire contour shape. This makes it possible to obtain contour shape data that more closely resembles the actual tire contour shape. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram showing how a tire groove measuring device 1 according to an embodiment of the present invention scans a groove 40 of a tire 30. FIG. [Figure 2] 1 is a block diagram showing a tire groove measuring device 1 according to an embodiment of the present invention. [Figure 3] 10 is a flowchart showing a process for correcting contour shape data 50 according to an embodiment of the present invention. [Figure 4] 10 is a flowchart showing a process for detecting a plurality of main grooves 41 from contour shape data 50 according to an embodiment of the present invention. [Figure 5] 1 is a diagram showing contour shape data 50 showing the contour shape of a portion of a tread 31 in which a groove 40 according to an embodiment of the present invention is provided. FIG. [Figure 6] 5(a) to 5(c) are diagrams showing a process for calculating the depth of a candidate for a groove 40 according to an embodiment of the present invention. [Figure 7] 5A to 5C are diagrams illustrating a scaling process according to an embodiment of the present invention. [Figure 8] 1A to 1C are diagrams showing a process for generating trajectory data 51 according to an embodiment of the present invention. [Figure 9] 10(a) to 10(c) are diagrams showing a process for generating camera shake component data 53 according to an embodiment of the present invention. [Figure 10] 10(a) to 10(c) are diagrams illustrating a correction process for contour shape data 50c according to an embodiment of the present invention. [Figure 11] 1 is a block diagram showing a tire groove measurement system 100 according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Similar components are designated by similar reference numerals, and redundant descriptions will be omitted. The following embodiments are merely examples, and the present invention is not limited to the following embodiments.

[0014] Fig. 1 is a diagram showing how a tire groove measuring device 1 according to an embodiment of the present invention scans a groove 40 of a tire 30. Fig. 2 is a block diagram showing the tire groove measuring device 1 according to this embodiment.

[0015] The tread 31 of the tire 30 has a plurality of grooves 40. The plurality of grooves 40 includes a main groove 41 and a secondary groove 42. The main groove 41 is a groove having a slip sign 44. The slip sign 44 may be a protrusion formed in the groove. The secondary groove 42 is a groove without a slip sign 44. The main groove 41 may be referred to as a groove, and the secondary groove 42 may be referred to as a slit and / or a sipe. In general, the depth of the secondary groove 42 may be shallower than the depth of the main groove 41.

[0016] The tire groove measuring device 1 of this embodiment is a handheld tire groove measuring device that a user holds and moves along the tread 31 of a tire 30 to measure the grooves 40. The tire groove measuring device 1 is equipped with a distance measurement sensor 21. The user can scan the tread 31, which has grooves 40, by moving the tire groove measuring device 1 along the surface of the tread 31 with the distance measurement sensor 21 facing the tread 31. When scanning, the user moves the tire groove measuring device 1 along the surface of the tread 31 while keeping the tire groove measuring device 1 in contact with the tread 31. The tire groove measuring device 1 may also be moved without contacting the tread 31. Arrow 15 shows an example of a direction in which the tire groove measuring device 1 can be moved. Note that the area of the tread 31 scanned using the tire groove measuring device 1 may include a portion of the portion connecting the tread 31 and the sidewall of the tire 30 (also referred to as a shoulder portion).

[0017] The distance measurement sensor 21 is, for example, a laser distance sensor. The distance measurement sensor 21 detects the distance between the tire 30 and the tire groove measurement device 1 by irradiating a tread 31 having grooves 40 with laser light and receiving reflected light. Any known method can be used to measure the distance. For example, a triangulation method can be used to measure the distance, but the measurement method is not limited to this. By using a laser distance sensor as the distance measurement sensor 21, there is no need to insert a probe such as a gauge into the groove 40, and the groove 40 can be measured with high accuracy in a short time.

[0018] As described above, the tire groove measuring device 1 is a handheld tire groove measuring device that the user moves along the tread 31 of the tire 30. Since the groove 40 can be measured while the vehicle is stopped at any position, user convenience can be improved.

[0019] 2, the tire groove measuring device 1 includes a processing device 10, a distance measurement sensor 21, an inertial sensor 22, a display panel 23, a plurality of operation switches 24, a communication device 25, and a battery 26. The battery 26 supplies power to each component of the tire groove measuring device 1.

[0020] The processing device 10 includes a processor 11 and storage media such as a read-only memory (ROM) 12 and a random access memory (RAM) 13. A computer program (or firmware) for causing the processor 11 to execute processing may be implemented in the ROM 12. The computer program may be provided to the tire groove measurement device 1 via a storage medium (such as a semiconductor memory or an optical disk) or a telecommunications line (such as the Internet). Such a computer program may be sold as commercial software.

[0021] The processor 11 is a semiconductor integrated circuit, and includes, for example, a central processing unit (CPU). The processor 11 sequentially executes a computer program stored in a ROM 12, which describes a group of instructions for executing various processes, to realize desired processing.

[0022] The ROM 12 is, for example, a writable memory (e.g., a PROM), a rewritable memory (e.g., a flash memory), or a read-only memory. The ROM 12 stores a computer program that controls the operation of the processor 11. The RAM 13 provides a working area for temporarily loading the computer program stored in the ROM 12 at boot time.

[0023] The processor 11 generates contour shape data indicating the contour shape of the tire 30 based on the output data of the distance measurement sensor 21.

[0024] The distance measurement sensor 21 irradiates a laser beam onto a tread 31 having grooves 40 formed therein, and detects the distance between the tire 30 and the tire groove measuring device 1. The distance measurement sensor 21 outputs data including information relating to the detected distance to the processor 11.

[0025] The inertial sensor 22 includes an acceleration sensor, an angular acceleration sensor, a magnetic sensor, etc., and outputs signals indicating the amount of movement, direction, and attitude. The inertial sensor 22 can output signals indicating various quantities such as the acceleration, speed, displacement, direction, and attitude of the tire groove measuring device 1.

[0026] The tire groove measuring device 1 is equipped with a plurality of operation switches 24. The tire groove measuring device 1 may be equipped with three or more operation switches 24. By operating the operation switches 24, the user can turn the power of the tire groove measuring device 1 on and off, start and end scanning, switch the display content of the display panel 23, send and receive data to and from external devices, and so on.

[0027] The display panel 23 displays various information in response to a user's operation on the tire groove measurement device 1. The display panel 23 is, for example, a liquid crystal panel. The processor 11 causes the display panel 23 to display information such as the operating status of the tire groove measurement device 1, information indicating the measurement results of the groove 40, and remaining battery capacity. The display panel 23 may be a display panel other than a liquid crystal panel, for example, an OLED (Organic Light-Emitting Diode) panel or an electronic paper panel.

[0028] The communication device 25 performs data communication between the tire groove measuring device 1 and an external device. For example, the communication device 25 transmits information about the contour shape of the tire 30 calculated by the processor 11 to the external device. The communication device 25 can perform wired communication and / or wireless communication. The communication device 25 can perform wired communication in accordance with a communication standard such as USB, IEEE1394 (registered trademark), or Ethernet (registered trademark). The communication device 25 can perform wireless communication in accordance with the Bluetooth (registered trademark) standard and / or the Wi-Fi (registered trademark) standard. The communication device 25 may also perform wireless communication using a mobile phone line.

[0029] Next, a process will be described in which the contour shape data 50 indicating the contour shape of the tire 30 is corrected to reduce the deviation between the contour shape data 50 and the actual contour shape of the tire 30. Fig. 3 is a flowchart showing the process of correcting the contour shape data 50.

[0030] First, the tread 31 of the tire 30, which has a plurality of grooves 40, is scanned (step S11). The scanning operation of the tread 31 is as described above with reference to FIG. 1. During the scanning operation, the distance measurement sensor 21 detects the distance between the tire 30 and the tire groove measuring device 1 by irradiating the tread 31, which has the grooves 40, with laser light and receiving reflected light. The processor 11 uses the output data of the inertial sensor 22 to calculate the amount of movement of the tire groove measuring device 1 during the scanning operation and the degree of inclination of the tire groove measuring device 1. Using the output data of the distance measurement sensor 21 and the inertial sensor 22, the processor 11 can acquire data on the distance between the tire groove measuring device 1 and each position along the scan line on the tread 31, which has the grooves 40.

[0031] The processor 11 can correct the output data of the distance measurement sensor 21 based on the output data of the inertial sensor 22. By correcting the output data of the distance measurement sensor 21 using the output data of the inertial sensor 22, it is possible to reduce disturbances in the measurement data caused by vibrations of the tire groove measuring device 1 during scanning, hand shake, etc. The processor 11 generates contour shape data indicating the contour shape of the tire 30 using the output data of the distance measurement sensor 21 and the inertial sensor 22. More specifically, the processor 11 generates contour shape data indicating the contour shape of the portion of the tread 31 in which the grooves 40 are provided.

[0032] Next, the processor 11 detects a plurality of main grooves 41 from the contour shape data (step S12). Fig. 4 is a flowchart showing the process of detecting a plurality of main grooves 41 from the contour shape data. Fig. 5 shows an example of contour shape data 50 that indicates the contour shape of the portion of the tread 31 where the grooves 40 are provided.

[0033] The left-right direction of the contour shape data 50 shown in the figure may be a direction generally along the surface of the tread 31 in the width direction of the tire 30. The up-down direction of the contour shape data 50 may be a direction generally along the radial direction of the tire 30. The height direction 56 is a direction along the up-down direction. The shorter the distance from the tire groove measuring device 1, the greater the height of the position. The contour shape data 50 may represent the cross-sectional shape of the tread 31 along the scan line. The relative height relationship between the tread 31 and the multiple grooves 40 can be obtained from the data on the distance between the tire 30 and the tire groove measuring device 1. For ease of understanding, the following description may focus on the respective heights of the tread 31 and the multiple grooves 40.

[0034] The processor 11 detects a plurality of candidates for the groove 40 from the contour shape data 50 (step S21 in FIG. 4). FIG. 5 shows the process of detecting the start edge portion and the end edge portion of the groove 40.

[0035] Processor 11 estimates the position where the increase in distance indicated by contour shape data 50 reaches a predetermined value A1 (second predetermined value) as the position of starting edge portion B[n] of groove 40 (n is an integer equal to or greater than 1). The increase in distance indicated by contour shape data 50 corresponds to a decrease in height.

[0036] For example, the minimum distance in a section of a predetermined length in the scanning direction (left-right direction in FIG. 5) along the surface of the tread 31 is used as a reference, and the position where the increase from the reference distance reaches a predetermined value A1 is estimated to be the position of the starting edge B[n]. The section of the predetermined length is, for example, 0.5 to 1.0 mm, but is not limited to this. The predetermined value A1 is, for example, 0.2 to 1.0 mm, but is not limited to this. Here, as an example, the predetermined value A1 is 0.2 mm.

[0037] The processor 11 estimates the position where the decrease in distance indicated by the contour shape data 50 reaches a predetermined value A2 (third predetermined value) as the position of the terminal edge C[n] of the groove 40. The decrease in distance indicated by the contour shape data 50 corresponds to an increase in height.

[0038] For example, the maximum distance in a section of a predetermined length in the scanning direction (left-right direction in FIG. 5) along the surface of the tread 31 is used as a reference, and the position where the decrease from the reference distance reaches a predetermined value A2 is estimated to be the position of the terminal edge portion C[n]. The predetermined value A2 is, for example, 0.2 to 1.0 mm, but is not limited to this. The predetermined value A1 and the predetermined value A2 may be the same value. Here, as an example, the predetermined value A2 is 0.2 mm.

[0039] The processor 11 detects a plurality of starting edge portions B[n] and ending edge portions C[n] from the contour shape data 50. The area having the starting edge portion B[n] as the starting end and the ending edge portion C[n] as the starting end can be set as a candidate for the groove 40.

[0040] Next, the processor 11 calculates the depth of each candidate for the groove 40. Fig. 6 is a diagram showing the process of calculating the depth of the candidate for the groove 40.

[0041] The processor 11 calculates the average value of the distance between the start edge portion B[n] and the end edge portion C[n] indicated by the contour shape data 50. Then, the processor 11 calculates the depth of the groove 40 as the difference between the calculated average value and the value of the distance at the position where the distance between the start edge portion B[n] and the end edge portion C[n] is the longest.

[0042] 6(a), processor 11 calculates the position of the midpoint D[n] between the start edge B[n] of groove 40 whose depth is to be calculated and the previous end edge C[n-1]. Processor 11 sets the median or average value of the distance between start edge B[n] and midpoint D[n] as the distance value of start edge B[n].

[0043] As shown in Figure 6(b), processor 11 calculates the position of the midpoint D[n+1] between the terminal edge C[n] of the groove 40 whose depth is to be calculated and the next starting edge B[n+1]. Processor 11 sets the median or average of the distances between the terminal edge C[n] and the midpoint D[n+1] as the distance value of the terminal edge C[n]. From the value calculated in this way, the average value of the distances of the starting edge B[n] and the distance of the terminal edge C[n] can be calculated.

[0044] For the groove 40 located at the left end of the plurality of grooves 40 aligned along the tread 31, the position of the midpoint D[n] may be a position that is a predetermined distance to the left of the starting edge B[n]. For the groove 40 located at the right end of the plurality of grooves 40 aligned along the tread 31, the position of the midpoint D[n+1] may be a position that is a predetermined distance to the right of the terminal edge C[n].

[0045] 6(c), processor 11 extracts the distance value at position G[n] where the distance between starting edge portion B[n] and ending edge portion C[n] is the longest. Processor 11 calculates the depth H[n] of groove 40 as the difference between the average value of the distances at starting edge portion B[n] and ending edge portion C[n] and the distance value at position G[n]. By performing the above process for each candidate for groove 40, the depth of each candidate for groove 40 can be calculated.

[0046] Next, the processor 11 selects the deepest groove (first groove) from among the multiple candidates for groove 40 (step S22 in FIG. 4). The processor 11 uses the depth value of the deepest first groove to select the main groove 41 from among the multiple candidates for groove 40 (step S23).

[0047] The processor 11 selects, from among the multiple candidate grooves 40, a groove whose depth differs from the depth of the first groove by a predetermined value Q (first predetermined value) or less as the main groove 41. The predetermined value Q is, for example, 1.5 to 2.0 mm, but is not limited thereto. Here, as an example, the predetermined value Q is 1.6 mm. By selecting, from among the multiple candidate grooves 40, a groove whose depth differs from the depth of the first groove by a predetermined value Q or less as the main groove 41, it is possible to prevent a relatively shallow sub-groove 42 from being mistakenly detected as the main groove 41.

[0048] Note that, once the deepest first groove is selected in step S22, the process of detecting multiple groove 40 candidates from the contour shape data 50 (step S21) may be performed again. In this case, the processor 11 updates the predetermined values A1 and A2 to a value obtained by multiplying the depth of the first groove by a first predetermined ratio. The first predetermined ratio is, for example, 30 to 50%, but is not limited to this. Here, as an example, the first predetermined ratio is 50%. The processor 11 uses the updated predetermined values A1 and A2 to again perform the process of estimating the positions of the starting edge portion B[n] and the ending edge portion C[n].

[0049] The processor 11 updates the multiple groove 40 candidates based on the re-estimated positions of the starting edge portion B[n] and the ending edge portion C[n]. Updating the multiple groove 40 candidates enables more accurate selection of the main groove 41. From the updated multiple groove 40 candidates, the processor 11 selects as the main groove 41 a groove whose depth differs from the depth of the first groove by within a first predetermined value Q.

[0050] Next, the processor 11 scales the contour shape data 50 (step S13 in FIG. 3). FIG. 7 is a diagram showing an example of the scaling process.

[0051] 7(a) shows contour shape data 50a generated by the processor 11. In this embodiment, processing is performed with a focus mainly on the main groove 41. The contour shape data may also include the shape of the secondary groove 42, but in order to clearly explain the characteristics of the processing in this embodiment, the secondary groove 42 is omitted from the example of contour shape data shown in the figure.

[0052] Based on the contour shape data 50a, the processor 11 detects both ends of a group to which a plurality of main grooves 41 aligned along the tread 31 belong. Specifically, of the plurality of main grooves 41 aligned along the tread 31, the processor 11 detects the main groove 41 located at the left end and the main groove 41 located at the right end. The processor 11 detects the starting edge B[1] of the main groove 41 located at the left end as the left end of the group. The processor 11 also detects the terminal edge C[n] of the main groove 41 located at the right end as the right end of the group. The starting edge and terminal edge can be detected, for example, using the method described above with reference to FIG. 5.

[0053] The processor 11 performs scaling to set the distance L1 between both ends of the group to a predetermined distance L2. Fig. 7(b) shows the contour shape data 50b after scaling. The predetermined distance L2 is a distance that is preset in the reference shape data 52 (Fig. 9) described later. The reference shape data 52 will be described in detail later.

[0054] For example, if the number of data samples at a predetermined interval L2 preset in the reference shape data 52 is a predetermined number of samples, the processor 11 performs scaling so that the number of data samples at an interval L1 becomes the predetermined number of samples. If the interval L1 is smaller than the predetermined interval L2, for example, the processor 11 performs up-conversion on the contour shape data 50a to change the interval L1 to the predetermined interval L2. If the interval L1 is larger than the predetermined interval L2, for example, the processor 11 performs down-conversion on the contour shape data 50a to change the interval L1 to the predetermined interval L2.

[0055] As shown in FIG. 7(b), by performing scaling, the number of samples S1 for the entire contour shape data 50a becomes the number of samples S2 for the contour shape data 50b. The processor 11 determines the midpoint M1 of the predetermined interval L2. The processor 11 extracts a region extending in the left and right directions from the midpoint M1 as the base point, having the number of samples S3, and obtains the contour shape data 50c shown in FIG. 7(c). The number of samples in the section from the left end of the contour shape data 50c to the midpoint M1 is S3 / 2. The number of samples in the section from the right end of the contour shape data 50c to the midpoint M1 is S3 / 2. The number of samples S3 corresponds to, for example, the number of samples in the reference shape data 52 (FIG. 9). By setting the number of samples in the contour shape data 50c to a value that is the same as or close to the number of samples in the reference shape data 52, processing can be performed smoothly.

[0056] Next, the processor 11 generates trajectory data indicating the trajectory of movement of the tire groove measuring device 1 (step S14 in FIG. 3). FIG.

[0057] Fig. 8(a) shows contour shape data 50c. As shown in Fig. 8(b), the processor 11 deletes data for the main grooves 41 from the contour shape data 50c. The start edge B[n] and end edge C[n] of each main groove 41 can be detected using the method described above with reference to Fig. 5, for example.

[0058] The processor 11 deletes data for the section between the start edge and the end edge of each main groove 41. For each main groove 41, the processor 11 may delete data for the section between a position a predetermined distance to the left of the start edge and a position a predetermined distance to the right of the end edge. This allows the edge portions of each main groove 41 to be appropriately deleted.

[0059] 8(c), the processor 11 performs a process of interpolating each of the deleted sections on the contour shape data 50c from which the data of the multiple main grooves 41 has been deleted, to generate trajectory data 51 that indicates the trajectory of movement of the tire groove measuring device 1. As a method of interpolation, for example, the section between the starting edge portion and the ending edge portion may be interpolated with a straight line or a curved line.

[0060] The data (i.e., trajectory data 51) obtained by interpolating the deleted portions of the main grooves 41 from the contour shape data 50c, from which the data for the portions of the main grooves 41 has been deleted, shows a shape that roughly follows the trajectory of movement of the tire groove measuring device 1 scanning the tire 30.

[0061] Next, the processor 11 generates hand vibration component data indicating a hand vibration component that occurs when the user moves the tire groove measuring device 1 while holding it in his / her hand (step S15 in FIG. 3). FIG. 9 is a diagram showing an example of a process for generating hand vibration component data 53.

[0062] 9(a) shows reference shape data 52 that indicates the contour shape of a tire 30 that serves as a reference and that has been prepared in advance. The reference shape data 52 is stored in advance in, for example, the ROM 12 (FIG. 2). The reference shape data 52 indicates the contour shape of the tread 31 when it is assumed that the tire 30 does not have grooves 40.

[0063] Fig. 9(b) shows trajectory data 51. Processor 11 compares trajectory data 51 with reference shape data 52 to generate camera shake component data 53 shown in Fig. 9(c). Processor 11 can generate camera shake component data 53, for example, by calculating the difference between reference shape data 52 and trajectory data 51.

[0064] Next, the processor 11 corrects the contour shape data 50c (FIG. 8(a)) before deleting the data of the portions of the main grooves 41 (step S16 in FIG. 3). FIG. 10 is a diagram showing an example of the correction process for the contour shape data 50c before deleting the data of the portions of the main grooves 41.

[0065] FIG. 10(a) shows camera shake component data 53. FIG. 10(b) shows contour shape data 50c before the data for the plurality of main grooves 41 is deleted. Processor 11 uses camera shake component data 53 to correct contour shape data 50c before the data for the plurality of main grooves 41 is deleted. Processor 11 corrects contour shape data 50c, for example, by adding camera shake component data 53 to contour shape data 50c. Correcting contour shape data 50c using camera shake component data 53 results in contour shape data 50d from which the camera shake component has been removed. FIG. 10(c) shows contour shape data 50d from which the camera shake component has been removed.

[0066] With the handheld tire groove measuring device 1, a user moves the tire groove measuring device 1 while holding it by hand when measuring the tire 30. For this reason, a discrepancy may occur between the contour shape data 50c obtained from the output data of the distance measurement sensor 21 and the actual contour shape of the tire 30.

[0067] According to this embodiment, trajectory data 51 indicating the trajectory of movement of the tire groove measuring device 1 is generated based on the contour shape data 50c obtained from the output data of the distance measurement sensor 21, and the trajectory data 51 is used to generate camera shake component data 53. By correcting the contour shape data 50c using the generated camera shake component data 53, it is possible to reduce the discrepancy between the contour shape data 50c and the contour shape of the actual tire 30. This makes it possible to obtain contour shape data 50d indicating a shape that is closer to the contour shape of the actual tire 30. By using the contour shape data 50d, it is possible to present to the user a shape that is closer to the contour shape of the actual tire 30. Furthermore, by using the contour shape data 50d, it is possible to accurately grasp the state of the main grooves 41 provided in the tire 30.

[0068] Furthermore, according to this embodiment, even when performing correction using the output data of the inertial sensor 22, it is possible to reduce the vibration and camera shake components that remain after correction using the output data of the inertial sensor 22.

[0069] If the shape of the secondary groove 42 is included in the above-described contour shape data 50a (FIG. 7(a)), the shape of the secondary groove 42 will remain as a camera shake component. In the process of correcting the contour shape data 50c using the camera shake component data 53 as described above, the shape of the secondary groove 42 is canceled out and does not appear in the contour shape data 50d. By not displaying the shape of the secondary groove 42, it becomes easier to recognize the shape of the main groove 41, which is more important.

[0070] The above-described processing of the processor 11 may be executed by an external device to the tire groove measuring device 1. Fig. 11 is a block diagram showing a tire groove measuring system 100 according to an embodiment of the present invention.

[0071] The tire groove measurement system 100 includes a tire groove measurement device 1 and an external device 101. The external device 101 is, for example, a server computer or a user terminal device. The user terminal device is, for example, a personal computer or a tablet computer.

[0072] The external device 101 includes a processing device 110 and a communication device 125. The processing device 110 includes a processor 111 and storage media such as a ROM 112 and a RAM 113. The explanation of the processor 111, ROM 112, RAM 113, and communication device 125 overlaps with the explanation of the processor 11, ROM 12, RAM 13, and communication device 25 of the tire groove measurement device 1, and therefore will be omitted here.

[0073] The processor 111 of the external device 101 performs the processing of the processor 11 described above, thereby achieving the same effect as described above.

[0074] The processor 111 may estimate the quality of the contour shape data 50d corrected using the camera shake component data 53, using an estimation model generated by machine learning.

[0075] For example, the external device 101 includes a storage device that stores a plurality of pieces of tire contour data, each piece having a predetermined quality. The storage device may be a hard disk drive (HDD), a solid state drive (SSD), cloud storage, or the like. The storage device may also be a ROM 112.

[0076] The processor 111 or another processor uses multiple pieces of contour shape data stored in the storage device as training data to generate an estimation model by machine learning, with the contour shape data as input and the quality of the contour shape data as output. The training data includes, for example, contour shape data that was successfully generated and contour shape data that was unsuccessfully generated.

[0077] The processor 111 or another processor can use the estimation model to estimate the quality of the contour shape data 50d corrected using the camera shake component data 53. For example, by estimating the quality of the contour shape data 50d using the estimation model, it is possible to determine whether the generation of the contour shape data 50d was successful or unsuccessful. By using the estimation model generated by machine learning, the quality of the corrected contour shape data 50d can be easily estimated.

[0078] The estimation of the quality of the contour shape data 50d using the estimation model may be performed by the processor 11 of the tire groove measurement device 1. Also, a processor installed in a device other than the tire groove measurement device 1 and the external device 101 may generate the estimation model and / or estimate the quality of the contour shape data 50d using the estimation model.

[0079] In the above-described embodiment, the tire groove measuring device 1 is a handheld type, but it may also be a stationary type. In a configuration in which the tire groove measuring device 1 is fixed at an arbitrary location, even if there is a positional deviation between the tire groove measuring device 1 and the tire 30, it is possible to generate contour shape data 50d with the amount of deviation reduced.

[0080] The embodiments of the present invention have been described above.

[0081] A tire groove measuring device 1 according to one embodiment of the present invention is a handheld tire groove measuring device 1 that a user moves along the tread 31 of a tire 30 to be measured to measure grooves 40 formed in the tread 31 of the tire 30, and includes a distance measuring sensor 21 that detects the distance between the tire 30 and the tire groove measuring device 1, and a processing device 10 that generates contour shape data 50 indicating the contour shape of the tire 30 based on output data from the distance measuring sensor 21. The tread 31 of the tire 30 is provided with a main groove 41 having a slip sign 44. The processing device 10 detects multiple main grooves 41 based on the contour shape data 50, deletes data for the multiple main grooves 41 from the contour shape data 50, interpolates the deleted portions of the multiple main grooves 41 for the contour shape data 50 from which the data for the multiple main grooves 41 has been deleted, generates trajectory data 51 indicating the trajectory of movement of the tire groove measuring device 1, compares the trajectory data 51 with reference shape data 52 indicating the contour shape of a previously prepared reference tire 30, generates camera shake component data 53 indicating camera shake components, and uses the camera shake component data 53 to correct the contour shape data 50 before the data for the multiple main grooves 41 was deleted.

[0082] With the handheld tire groove measuring device 1, the user holds and moves the tire groove measuring device 1 by hand when measuring the tire 30, so there may be a discrepancy between the contour shape data 50 obtained from the output data of the distance measuring sensor 21 and the actual contour shape of the tire 30.

[0083] According to one embodiment of the present invention, trajectory data 51 indicating the trajectory of movement of tire groove measurement device 1 is generated based on contour shape data 50 obtained from output data of distance measurement sensor 21, and camera shake component data 53 is generated using this trajectory data 51. By correcting contour shape data 50 using the generated camera shake component data 53, it is possible to reduce the discrepancy between contour shape data 50 and the actual contour shape of tire 30. This makes it possible to obtain contour shape data 50 that indicates a shape that is closer to the contour shape of the actual tire 30.

[0084] In one embodiment, the processing device 10 may detect both ends B[1], C[n] of a group of multiple main grooves 41 aligned along the tread 31, delete data for the multiple main grooves 41 from the contour shape data 50 that has been scaled to set the distance L1 between the two ends to a predetermined distance L2, and perform interpolation to generate trajectory data 51.

[0085] This makes it possible to generate trajectory data 51 of a size suitable for comparison with reference shape data 52.

[0086] In one embodiment, the processing device 10 may calculate the difference between the reference shape data 52 and the trajectory data 51 to generate the hand shake component data 53.

[0087] As a result, the hand-shake component data 53 can be generated from the reference shape data 52 and the locus data 51.

[0088] In one embodiment, the processing device 10 may add camera shake component data 53 to the contour shape data 50 before deleting the data for the portions of the multiple main grooves 41, thereby correcting the contour shape data 50 before deleting the data for the portions of the multiple main grooves 41.

[0089] This makes it possible to obtain the contour shape data 50 that shows a shape that is closer to the contour shape of the actual tire 30.

[0090] In one embodiment, the processing device 10 detects multiple groove 40 candidates based on contour shape data 50 generated based on output data from the distance measurement sensor 21, selects a first groove 40 that is the deepest among the multiple groove 40 candidates, and detects as the main groove 41 a groove 40 among the multiple groove 40 candidates whose depth differs from that of the first groove 40 by within a first predetermined value.

[0091] This allows the main groove 41 to be detected from among the multiple grooves 40.

[0092] In one embodiment, the processing device 10 may estimate the position where the increase in distance indicated by the contour shape data 50 generated based on the output data of the distance measurement sensor 21 becomes a second predetermined value A1 as the position of the starting edge portion B[n] of the groove 40, and may estimate the position where the decrease in distance indicated by the output data becomes a third predetermined value A2 as the position of the terminal edge portion C[n] of the groove 40.

[0093] This allows a plurality of candidates for the groove 40 to be detected using the contour shape data 50.

[0094] In one embodiment, the processing device 10 may calculate the average value of the distance between the starting edge portion and the ending edge portion, and calculate the depth H[n] of the groove 40 as the difference between the distance at the point where the distance between the starting edge portion and the ending edge portion is the longest and the average value.

[0095] This makes it possible to calculate the depth of each of the multiple groove 40 candidates.

[0096] In one embodiment, the distance sensor 21 may be a laser distance sensor.

[0097] This eliminates the need to insert a probe such as a gauge into the groove 40 of the tire 30, and allows the groove 40 of the tire 30 to be measured with high accuracy in a short time.

[0098] In one embodiment, the processing device 10 may estimate the quality of the contour shape data 50 corrected using the camera shake component data 53 using an estimation model generated by machine learning.

[0099] By using an estimation model generated by machine learning, the quality of the corrected contour shape data 50 can be easily estimated.

[0100] A tire groove measurement system 100 according to one embodiment of the present invention measures grooves 40 formed in the tread 31 of a tire 30 using a handheld tire groove measurement device 1 that a user moves along the tread 31 of the tire 30 to be measured, and includes a distance measurement sensor 21 provided in the tire groove measurement device 1 to detect the distance between the tire 30 and the tire groove measurement device 1, and processing devices 10, 110 that generate contour shape data 50 indicating the contour shape of the tire 30 based on output data from the distance measurement sensor 21. The tread 31 of the tire 30 is provided with a main groove 41 having a slip sign 44. The processing device 10, 110 detects multiple main grooves 41 based on the contour shape data 50, deletes data for the multiple main grooves 41 from the contour shape data 50, interpolates the deleted portions of the multiple main grooves 41 for the contour shape data 50 from which the data for the multiple main grooves 41 has been deleted, generates trajectory data 51 indicating the trajectory of movement of the tire groove measuring device 1, compares the trajectory data 51 with reference shape data 52 indicating the contour shape of a previously prepared reference tire 30, generates camera shake component data 53 indicating the camera shake component, and uses the camera shake component data 53 to correct the contour shape data 50 before the data for the multiple main grooves 41 was deleted.

[0101] With the handheld tire groove measuring device 1, the user holds and moves the tire groove measuring device 1 by hand when measuring the tire 30, so there may be a discrepancy between the contour shape data 50 obtained from the output data of the distance measuring sensor 21 and the actual contour shape of the tire 30.

[0102] According to one embodiment of the present invention, trajectory data 51 indicating the trajectory of movement of tire groove measurement device 1 is generated based on contour shape data 50 obtained from output data of distance measurement sensor 21, and camera shake component data 53 is generated using this trajectory data 51. By correcting contour shape data 50 using the generated camera shake component data 53, it is possible to reduce the discrepancy between contour shape data 50 and the actual contour shape of tire 30. This makes it possible to obtain contour shape data 50 that indicates a shape that is closer to the contour shape of the actual tire 30.

[0103] In one embodiment, the processing device 10, 110 may estimate the quality of the contour shape data 50 corrected using the camera shake component data 53 using an estimation model generated by machine learning.

[0104] By using an estimation model generated by machine learning, the quality of the corrected contour shape data 50 can be easily estimated.

[0105] A tire groove measurement method according to one embodiment of the present invention is a tire groove measurement method in which a handheld tire groove measuring device 1 that a user moves along the tread 31 of a tire 30 to be measured is used to measure grooves 40 provided in the tread 31 of the tire 30. The tread 31 of the tire 30 is provided with a main groove 41 having a slip sign 44. The tire groove measurement method includes detecting the distance between the tire 30 and the tire groove measuring device 1 using a distance measuring sensor 21, generating contour shape data 50 indicating the contour shape of the tire 30 based on output data of the distance measuring sensor 21, detecting a plurality of main grooves 41 based on the contour shape data 50, deleting data for the plurality of main grooves 41 from the contour shape data 50, interpolating the deleted portions of the plurality of main grooves 41 from the contour shape data 50 from which the data for the portions of the plurality of main grooves 41 has been deleted, to generate trajectory data 51 indicating the trajectory of movement of the tire groove measuring device 1, comparing the trajectory data 51 with reference shape data 52 indicating the contour shape of a previously prepared reference tire 30, to generate camera shake component data 53 indicating a camera shake component, and correcting the contour shape data 50 before the data for the portions of the plurality of main grooves 41 has been deleted using the camera shake component data 53.

[0106] With the handheld tire groove measuring device 1, the user holds and moves the tire groove measuring device 1 by hand when measuring the tire 30, so there may be a discrepancy between the contour shape data 50 obtained from the output data of the distance measuring sensor 21 and the actual contour shape of the tire 30.

[0107] According to one embodiment of the present invention, trajectory data 51 indicating the trajectory of movement of tire groove measurement device 1 is generated based on contour shape data 50 obtained from output data of distance measurement sensor 21, and camera shake component data 53 is generated using this trajectory data 51. By correcting contour shape data 50 using the generated camera shake component data 53, it is possible to reduce the discrepancy between contour shape data 50 and the actual contour shape of tire 30. This makes it possible to obtain contour shape data 50 that indicates a shape that is closer to the contour shape of the actual tire 30.

[0108] In one embodiment, the tire groove measurement method may further include estimating the quality of the contour shape data 50 corrected using the camera shake component data 53, using an estimation model generated by machine learning.

[0109] By using an estimation model generated by machine learning, the quality of the corrected contour shape data 50 can be easily estimated.

[0110] The above-described embodiments are merely examples of the present invention and are not intended to limit the scope of the present invention. Furthermore, embodiments in which the components described in the above-described embodiments are appropriately combined are also possible. The present invention allows for modifications, substitutions, additions, omissions, and the like within the scope of the claims or their equivalents. [Industrial Applicability]

[0111] The present invention is particularly useful in the field of tire groove measurement. [Explanation of symbols]

[0112] 1: tire groove measuring device, 10: processing device, 11: processor, 12: ROM, 13: RAM, 21: distance measuring sensor, 22: inertial sensor, 23: display panel, 24: operation switch, 25: communication device, 26: battery, 30: tire, 31: tread, 40: groove, 41: main groove, 42: secondary groove, 44: slip sign, 50: contour shape data, 51: trajectory data, 52: reference shape data, 53: camera shake component data, 100: tire groove measuring system, 101: external device, 110: processing device, 111: processor, 112: ROM, 113: RAM, 125: communication device

Claims

1. A handheld tire groove measuring device that a user moves along the tread of a tire to be measured and measures grooves provided in the tread of the tire, a distance measuring sensor that detects the distance between the tire and the tire groove measuring device; a processing device that generates contour shape data indicating the contour shape of the tire based on the output data of the distance measurement sensor; Equipped with The tire tread is provided with a main groove having a slip sign, The processing device includes: detecting a plurality of main grooves based on the contour shape data; deleting data of the plurality of main grooves from the contour shape data; interpolating the deleted portions of the main grooves from the contour shape data from which the data of the portions of the main grooves has been deleted, to generate trajectory data indicating a trajectory of movement of the tire groove measuring device; generating hand-shake component data indicating a hand-shake component by comparing the trajectory data with reference shape data indicating a tire contour shape that is a reference prepared in advance; The tire groove measuring device uses the camera shake component data to correct the contour shape data before deleting data on the plurality of main groove portions.

2. The processing device includes: detecting both ends of the group of the plurality of main grooves aligned along the tread; 2. The tire groove measuring device according to claim 1, wherein data of the plurality of main grooves is deleted from the contour shape data that has been scaled to set the distance between the two end portions at a predetermined distance, and the locus data is generated by performing the interpolation.

3. The tire groove measuring device according to claim 1 or 2, wherein the processing device generates the hand vibration component data by calculating a difference between the reference shape data and the trajectory data.

4. 3. The tire groove measuring device according to claim 1, wherein the processing device adds the camera shake component data to the contour shape data before deleting the data of the plurality of main groove portions, thereby correcting the contour shape data before deleting the data of the plurality of main groove portions.

5. The processing device includes: detecting a plurality of groove candidates based on the contour shape data generated based on the output data of the distance measuring sensor; selecting a first groove having the deepest depth from among the plurality of groove candidates; 3. The tire groove measuring device according to claim 1, wherein a groove having a difference in depth from the first groove depth within a first predetermined value is detected as a main groove from among the plurality of groove candidates.

6. 6. The tire groove measuring device of claim 5, wherein the processing device estimates the position where the increase in distance indicated by the contour shape data generated based on the output data of the distance measuring sensor is a second predetermined value as the position of the starting edge of the groove, and estimates the position where the decrease in distance indicated by the output data is a third predetermined value as the position of the terminal edge of the groove.

7. The processing device includes: calculating an average value of the distance of the starting edge portion and the distance of the ending edge portion; The tire groove measuring device according to claim 6, wherein the difference between the maximum distance between the starting edge portion and the terminal edge portion and the average value is calculated as the groove depth.

8. The tire groove measuring device according to claim 1 or 2, wherein the distance measuring sensor is a laser distance sensor.

9. 3. The tire groove measuring device according to claim 1, wherein the processing device estimates the quality of the contour shape data corrected using the camera shake component data using an estimation model generated by machine learning, the estimation model having the corrected contour shape data as an input and the quality as an output.

10. A tire groove measurement system in which a user measures grooves provided in a tire tread using a handheld tire groove measurement device that is moved along the tread of the tire to be measured, a distance measuring sensor provided in the tire groove measuring device to detect a distance between the tire and the tire groove measuring device; a processing device that generates contour shape data indicating the contour shape of the tire based on the output data of the distance measurement sensor; Equipped with The tire tread is provided with a main groove having a slip sign, The processing device includes: detecting a plurality of main grooves based on the contour shape data; deleting data of the plurality of main grooves from the contour shape data; interpolating the deleted portions of the main grooves from the contour shape data from which the data of the portions of the main grooves has been deleted, to generate trajectory data indicating a trajectory of movement of the tire groove measuring device; generating hand-shake component data indicating a hand-shake component by comparing the trajectory data with reference shape data indicating a tire contour shape that is a reference prepared in advance; a tire groove measurement system that uses the camera shake component data to correct the contour shape data before deleting data on the plurality of main groove portions;

11. 11. The tire groove measurement system according to claim 10, wherein the processing device estimates the quality of the contour shape data corrected using the camera shake component data using an estimation model generated by machine learning, the estimation model having the corrected contour shape data as an input and the quality as an output.

12. A tire groove measurement method in which a user uses a handheld tire groove measurement device that is moved along the tread of a tire to be measured to measure grooves provided in the tread of the tire, The tire tread is provided with a main groove having a slip sign, The tire groove measuring method includes: Detecting the distance between the tire and the tire groove measuring device using a distance measuring sensor; generating contour shape data indicating a contour shape of the tire based on the output data of the distance measurement sensor; detecting a plurality of main grooves based on the contour shape data; deleting data of the plurality of main grooves from the contour shape data; interpolating the deleted portions of the main grooves from the contour shape data from which the data of the portions of the main grooves has been deleted, and generating trajectory data indicating a trajectory of movement of the tire groove measuring device; generating hand vibration component data indicating a hand vibration component by comparing the trajectory data with reference shape data indicating a tire contour shape that serves as a reference and that is prepared in advance; correcting the contour shape data before deleting the data of the plurality of main groove portions using the hand vibration component data; A tire groove measurement method, comprising:

13. 13. The tire groove measurement method according to claim 12, further comprising: estimating quality of the contour shape data corrected using the camera shake component data using an estimation model generated by machine learning, the estimation model having the corrected contour shape data as an input and the quality as an output.

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