Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
  • G01B11/00—Measuring arrangements characterised by the use of optical techniques
  • G01B11/22—Measuring arrangements characterised by the use of optical techniques for measuring depth
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
  • G01B11/00—Measuring arrangements characterised by the use of optical techniques
  • G01B11/24—Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
  • G01M17/00—Testing of vehicles
  • G01M17/007—Wheeled or endless-tracked vehicles
  • G01M17/02—Tyres

Definitions

• the present invention relates to a tire groove measuring device, a tire groove measuring system, and a tire groove measuring method.
• the treads of tires fitted to automobiles and other vehicles have grooves. As the vehicle travels, the tires wear down and the depth of the grooves becomes shallower, so it is necessary to measure the groove depth and manage the condition of the tires.
• Patent Document 1 discloses a measuring device that measures the grooves in the tread of a tire.
• the measuring device is fixed to the ground as a car stopper for a parking space.
• Patent Document 1 discloses a technique for parking a vehicle so that the tire comes into contact with the measuring device, which is a car stopper, and measuring the tire grooves.
• Patent Document 1 The measurement device in Patent Document 1 is fixed to the ground, so there is an issue that groove measurements can only be performed at the location where the measurement device is installed. In addition, it is necessary to move the vehicle 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.
• a tire groove measuring device is a handheld tire groove measuring device that is moved by a user along the tread of a tire to be measured and measures the grooves in the tread of the tire.
• the device includes a distance measuring 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 measuring sensor.
• the tire tread has main grooves with slip signs.
• the processing device detects multiple main grooves based on the contour shape data, deletes data of the multiple main groove portions from the contour shape data, and interpolates the deleted portions of the multiple main grooves from the contour shape data from which the data of the multiple main groove portions has been deleted, generating trajectory data that indicates the trajectory of the movement of the tire groove measuring device, comparing the trajectory data with reference shape data that indicates the contour shape of a tire that is a reference and that has been prepared in advance, generating camera shake component data that indicates camera shake components, and correcting the contour shape data before the data of the multiple main groove portions is deleted using the camera shake component data.
• a tire groove measurement system is a tire groove measurement system that uses a handheld tire groove measurement device that a user moves along the tread of a tire to be measured to measure grooves in the tread of the tire.
• the tire groove measurement device is provided with a distance measurement sensor that 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 the output data of the distance measurement sensor.
• the tire tread is provided with main grooves that have slip signs
• the processing device detects multiple main grooves based on the contour shape data, deletes data of the multiple main groove portions from the contour shape data, interpolates the deleted portions of the multiple main grooves from the contour shape data from which the data of the multiple main groove portions has been deleted, generates trajectory data that indicates the trajectory of the movement of the tire groove measurement device, compares the trajectory data with reference shape data that indicates the contour shape of a tire that is a reference prepared in advance, generates camera shake component data that indicates camera shake components, and uses the camera shake component data to correct the contour shape data before deleting the data of the multiple main groove portions.
• a tire groove measuring method is a tire groove measuring method in which a user uses a handheld tire groove measuring 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 being provided with a main groove having a slip sign, and 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 the contour shape of the tire based on output data from the distance measuring sensor; detecting multiple main grooves based on the contour shape data; deleting data of the multiple main groove portions from the contour shape data; interpolating the deleted portions of the multiple main grooves from the contour shape data from which the data of the multiple main groove portions has been deleted, thereby generating trajectory data indicating the trajectory of the movement of the tire groove measuring device; comparing the trajectory data with reference shape data indicating the contour shape of a tire that is a reference prepared in advance to generate camera shake component data indicating camera shake components; and correcting the contour shape data before deleting the
• trajectory data showing the trajectory of the movement of the tire groove measuring device is generated based on the contour shape data obtained from the output data of the distance measurement sensor, and the trajectory data is used to generate camera shake component data.
• FIG. 1 is a diagram showing a state in which a tire groove measuring device 1 according to an embodiment of the present invention scans a groove 40 of a tire 30.
• FIG. 1 is a block diagram showing a tire groove measuring device 1 according to an embodiment of the present invention.
• 5 is a flowchart showing a process for correcting contour shape data 50 according to the embodiment of the present invention.
• 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.
• FIG. 5 is a diagram showing contour shape data 50 indicating 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.
• 5A to 5C are diagrams illustrating a process for calculating the depth of candidates for a groove 40 according to an embodiment of the present invention.
• 5A to 5C are diagrams illustrating a scaling process according to an embodiment of the present invention.
• 5A to 5C are diagrams illustrating a process for generating trajectory data 51 according to an embodiment of the present invention.
• 5A to 5C are diagrams showing a process for generating camera shake component data 53 according to an embodiment of the present invention.
• 5A to 5C are diagrams illustrating a correction process for contour shape data 50c according to an embodiment of the present invention.
• 1 is a block diagram showing a tire groove measurement system 100 according to an embodiment of the present invention.
• 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.
• 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 provided in the groove.
• the secondary groove 42 is a groove not having 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.
• the tire groove measuring device 1 of this embodiment is a handheld tire groove measuring device that a user holds by hand and moves along the tread 31 of the tire 30 to be measured to measure the groove 40.
• the tire groove measuring device 1 is equipped with a distance measuring sensor 21.
• the user can scan the tread 31 with the groove 40 by moving the tire groove measuring device 1 along the surface of the tread 31 with the distance measuring sensor 21 facing the tread 31.
• 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 be moved without contacting the tread 31.
• the arrow 15 shows an example of a direction in which the tire groove measuring device 1 is moved. Note that the range of the tread 31 scanned using the tire groove measuring device 1 may include a part of the portion (also called the shoulder portion) connecting the tread 31 and the sidewall of the tire 30.
• 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 measuring device 1 by irradiating a laser beam onto the tread 31 in which the grooves 40 are formed and receiving the 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.
• a laser distance sensor as the distance measurement sensor 21, it is not necessary 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.
• 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 in any position, it is possible to improve user convenience.
• the tire groove measuring device 1 includes a processing device 10, a distance measuring 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.
• the processing device 10 includes a processor 11 and storage media such as a ROM (Read Only Memory) 12 and a RAM (Random Access Memory) 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 measuring device 1 via a storage medium (e.g., a semiconductor memory or an optical disk) or a telecommunications line (e.g., the Internet).
• a storage medium e.g., a semiconductor memory or an optical disk
• a telecommunications line e.g., the Internet
• Processor 11 is a semiconductor integrated circuit, and includes, for example, a central processing unit (CPU). Processor 11 sequentially executes computer programs stored in ROM 12, which contain commands for executing various processes, to realize the desired processing.
• CPU central processing unit
• ROM 12 is, for example, a writable memory (e.g., PROM), a rewritable memory (e.g., flash memory), or a read-only memory.
• ROM 12 stores a computer program that controls the operation of processor 11.
• RAM 13 provides a working area for loading the computer program stored in ROM 12 at boot time.
• 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.
• the distance measurement sensor 21 irradiates a laser beam onto a tread 31 having grooves 40, and detects the distance between the tire 30 and the tire groove measuring device 1.
• the distance measurement sensor 21 outputs data including information regarding the detected distance to the processor 11.
• the inertial sensor 22 is equipped with 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.
• the tire groove measuring device 1 is equipped with multiple operation switches 24.
• the tire groove measuring device 1 may be equipped with three or more operation switches 24.
• a user can operate the operation switches 24 to turn the power of the tire groove measuring device 1 on and off, start and end a scan, switch the display content of the display panel 23, send and receive data to and from external devices, etc.
• the display panel 23 displays various information in response to the user's operation of the tire groove measuring 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 measuring device 1, information showing 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.
• 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 conforming to a communication standard such as USB, IEEE1394 (registered trademark), or Ethernet (registered trademark).
• the communication device 25 can perform wireless communication conforming to the Bluetooth (registered trademark) standard and/or the Wi-Fi (registered trademark) standard.
• the communication device 25 may perform wireless communication using a mobile phone line.
• Figure 3 is a flowchart showing the process for correcting the contour shape data 50.
• 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.
• the distance measurement sensor 21 irradiates the tread 31, which has the grooves 40, with laser light and receives the reflected light to detect the distance between the tire 30 and the tire groove measuring device 1.
• 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.
• the processor 11 can obtain distance data between each position along the scan line on the tread 31, which has the grooves 40, and the tire groove measuring device 1, using the output data of the distance measurement sensor 21 and the inertial sensor 22.
• the processor 11 may 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 uses the output data of the distance measurement sensor 21 and the inertial sensor 22 to generate contour shape data indicating the contour shape of the tire 30. 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.
• FIG. 4 is a flowchart showing the process of detecting the multiple 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 in which the grooves 40 are provided.
• the left-right direction of the contour shape data 50 shown in the figure may be a direction that generally follows 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 that generally follows the radial direction of the tire 30.
• the height direction 56 is a direction along the up-down direction. The smaller the distance between the tire groove measuring device 1, the greater the height of the position may be.
• 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 easy understanding, the following description may focus on the respective heights of the tread 31 and the multiple grooves 40.
• the processor 11 detects multiple candidates for grooves 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.
• the processor 11 estimates that the position where the increase in distance indicated by the contour shape data 50 reaches a predetermined value A1 (second predetermined value) is the position of the starting edge portion B[n] of the groove 40 (n is an integer equal to or greater than 1).
• the increase in distance indicated by the contour shape data 50 corresponds to a decrease in height.
• the minimum distance in a section of a predetermined length in the scanning direction (left and right direction in Figure 5) along the surface of the tread 31 is used as a reference, and the position where the increase from the reference distance becomes a predetermined value A1 is estimated to be the position of the starting edge portion 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.
• the predetermined value A1 is 0.2 mm.
• the processor 11 estimates that the position where the amount of decrease in distance indicated by the contour shape data 50 reaches a predetermined value A2 (third predetermined value) is the position of the terminal edge portion C[n] of the groove 40.
• the decrease in distance indicated by the contour shape data 50 corresponds to an increase in height.
• the maximum distance in a section of a predetermined length in the scanning direction (left and 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.
• the predetermined value A2 is 0.2 mm.
• the processor 11 detects multiple start edge portions B[n] and end edge portions C[n] from the contour shape data 50.
• the area with the start edge portion B[n] as the start end and the end edge portion C[n] as the start end can be a candidate for the groove 40.
• Figure 6 shows the process of calculating the depth of the groove 40 candidates.
• Processor 11 calculates the average value of the distance of the start edge portion B[n] and the distance of the end edge portion C[n] indicated by the contour shape data 50. Then, 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 is calculated as the depth of groove 40.
• processor 11 calculates the position of the midpoint D[n] between the start edge B[n] of the groove 40 for which the depth is to be calculated and the previous end edge C[n-1]. Processor 11 determines 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].
• processor 11 calculates the position of the midpoint D[n+1] between the terminal edge C[n] of groove 40, the depth of which is to be calculated, and the next starting edge B[n+1].
• Processor 11 determines the median or average value of the distance between terminal edge C[n] and midpoint D[n+1] as the distance value of terminal edge C[n]. From the value calculated in this way, the average value of the distance of starting edge B[n] and the distance of terminal edge C[n] can be calculated.
• the position of the midpoint D[n] may be a position that is a predetermined distance to the left of the starting edge portion B[n].
• the position of the midpoint D[n+1] may be a position that is a predetermined distance to the right of the terminal edge portion C[n].
• 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].
• the processor 11 selects the deepest groove (first groove) from among the multiple groove 40 candidates (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 groove 40 candidates (step S23).
• the processor 11 selects, from among the multiple groove 40 candidates, a groove whose depth differs from the depth of the first groove by within a predetermined value Q (first predetermined value) as the main groove 41.
• the predetermined value Q is, for example, 1.5 to 2.0 mm, but is not limited to this.
• the predetermined value Q is 1.6 mm.
• the processor 11 updates the predetermined values A1 and A2 to a value obtained by multiplying the depth of the first groove by the first predetermined ratio.
• the first predetermined ratio is, for example, 30 to 50%, but is not limited to this.
• the first predetermined ratio is 50%.
• the processor 11 uses the updated predetermined values A1 and A2 to perform the process of estimating the positions of the starting edge portion B[n] and the ending edge portion C[n] again.
• 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]. By updating the multiple groove 40 candidates, the main groove 41 can be selected with greater accuracy.
• the processor 11 selects, from the multiple updated groove 40 candidates, a groove whose depth differs from the depth of the first groove by within a first predetermined value Q as the main groove 41.
• the processor 11 scales the contour shape data 50 (step S13 in FIG. 3).
• FIG. 7 shows an example of the scaling process.
• FIG. 7(a) shows the contour shape data 50a generated by the processor 11.
• 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 easily explain the characteristics of the processing in this embodiment, the secondary groove 42 has been omitted from the example of contour shape data shown in the figure.
• the processor 11 detects both ends of a group to which multiple main grooves 41 aligned along the tread 31 belong, based on the contour shape data 50a. Specifically, it detects the main groove 41 located at the left end and the main groove 41 located at the right end of the multiple main grooves 41 aligned along the tread 31. The processor 11 detects the starting edge portion B[1] of the main groove 41 located at the left end as the left end of the group. In addition, it detects the terminal edge portion C[n] of the main groove 41 located at the right end as the right end of the group. The starting edge portion and the terminal edge portion can be detected, for example, by the method described above with reference to FIG. 5.
• the processor 11 performs scaling to set the distance L1 between both ends of the group to a predetermined distance L2 .
• Fig. 7B shows contour shape data 50b after scaling.
• the predetermined distance L2 is a distance that is preset in reference shape data 52 (Fig. 9) to be described later.
• the reference shape data 52 will be described in detail later.
• the processor 11 when 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.
• the processor 11 When 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 set the interval L1 to the predetermined interval L2 .
• the processor 11 When 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 set the interval L1 to the predetermined interval L2 .
• the number of samples S1 of the entire contour shape data 50a becomes the number of samples S2 of the contour shape data 50b.
• the processor 11 determines the midpoint M1 of the predetermined interval L2 .
• the processor 11 cuts out an area that spreads in the left and right directions from the midpoint M1 as a base point and has the number of samples S3, and obtains the contour shape data 50c shown in FIG. 7C.
• the number of samples in the section between the left end of the contour shape data 50c and the midpoint M1 is S3/2.
• the number of samples in the section between the right end of the contour shape data 50c and the midpoint M1 is S3/2.
• the number of samples S3 corresponds to the number of samples of the reference shape data 52 (FIG. 9), for example.
• FIG. 8 is a diagram showing an example of a process for generating the trajectory data 51.
• FIG. 8(a) shows contour shape data 50c.
• the processor 11 deletes the data of the main grooves 41 from the contour shape data 50c, as shown in FIG. 8(b).
• the start edge portion B[n] and the end edge portion C[n] of each main groove 41 can be detected, for example, by the method described above with reference to FIG. 5.
• 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, 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 may be deleted. This allows the edge portions of each main groove 41 to be appropriately deleted.
• 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 portions of the multiple main grooves 41 has been deleted, and generates trajectory data 51 that indicates the trajectory of the movement of the tire groove measuring device 1.
• the section between the start edge portion and the end edge portion may be complemented with a straight line or a curved line.
• the data 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 (i.e., the trajectory data 51) shows a shape that generally follows the trajectory of the movement of the tire groove measuring device 1 scanning the tire 30.
• FIG. 9 is a diagram showing an example of a process for generating hand vibration component data 53.
• FIG. 9(a) shows reference shape data 52 that indicates the contour shape of a tire 30 that is a reference prepared in advance.
• the reference shape data 52 is stored in advance, for example, in 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.
• 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, for example, calculate the difference between reference shape data 52 and trajectory data 51 to generate camera shake component data 53.
• FIG. 10 is a diagram showing an example of the correction process of the contour shape data 50c before deleting the data of the portions of the main grooves 41.
• FIG. 10(a) shows camera shake component data 53.
• FIG. 10(b) shows contour shape data 50c before the data of the multiple main grooves 41 is deleted.
• Processor 11 uses camera shake component data 53 to correct contour shape data 50c before the data of the multiple 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.
• contour shape data 50d from which the camera shake component has been removed is obtained.
• FIG. 10(c) shows contour shape data 50d from which the camera shake component has been removed.
• the user When measuring the tire 30 with the handheld tire groove measuring device 1, the user holds the tire groove measuring device 1 in their hands and moves it around. This can result in discrepancies between the contour shape data 50c obtained from the output data of the distance measuring sensor 21 and the actual contour shape of the tire 30.
• trajectory data 51 indicating the trajectory of the 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.
• the contour shape data 50c By correcting the contour shape data 50c using the generated camera shake component data 53, it is possible to reduce the deviation between the contour shape data 50c and the actual contour shape of the tire 30.
• the contour shape data 50d it is possible to present to the user a shape closer to the contour shape of the actual tire 30.
• the contour shape data 50d it is possible to accurately grasp the state of the main groove 41 provided in the tire 30.
• the shape of the secondary groove 42 will remain as a camera shake component.
• the shape of the secondary groove 42 is offset and will no longer appear in the contour shape data 50d.
• FIG. 11 is a block diagram showing a tire groove measuring system 100 according to an embodiment of the present invention.
• 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.
• 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 measuring device 1, so will be omitted here.
• the processor 111 of the external device 101 performs the processing of the processor 11 described above. This also achieves the same effect as described above.
• 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.
• the external device 101 includes a storage device that stores multiple pieces of contour shape data that indicate the contour shape of a tire and have a quality that is specified in advance.
• the storage device may be a hard disk drive (HDD), a solid state drive (SSD), cloud storage, etc.
• the storage device may be a ROM 112.
• Processor 111 or another processor uses multiple pieces of contour shape data stored in the storage device as training data, and generates an estimation model through machine learning, using 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 has been successfully generated and contour shape data that has been unsuccessfully generated.
• 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.
• 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 measuring device 1. Also, a processor installed in a device other than the tire groove measuring 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.
• the tire groove measuring device 1 is a handheld type, but the tire groove measuring device 1 may be a stationary type. In a configuration in which the tire groove measuring device 1 is fixed at an arbitrary location, even if the positional relationship between the tire groove measuring device 1 and the tire 30 is misaligned, contour shape data 50d can be generated with the amount of misalignment reduced.
• a tire groove measuring device 1 is a handheld tire groove measuring device 1 that a user moves along the tread 31 of a tire 30 to be measured and measures the grooves 40 provided 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 the output data of 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 the multiple main grooves 41 based on the contour shape data 50, deletes the data of 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 of the multiple main grooves 41 has been deleted, generates trajectory data 51 indicating the trajectory of the 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 of the multiple main grooves 41 was deleted.
• 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.
• trajectory data 51 indicating the trajectory of the movement of the tire groove measuring device 1 is generated based on the contour shape data 50 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.
• the contour shape data 50 is used to generate camera shake component data 53.
• 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 both ends to a predetermined distance L2 , and generate trajectory data 51 by performing interpolation.
• trajectory data 51 of a size suitable for comparison with the reference shape data 52.
• the processing device 10 may calculate the difference between the reference shape data 52 and the trajectory data 51 to generate the camera shake component data 53.
• 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, to correct the contour shape data 50 before deleting the data for the portions of the multiple main grooves 41.
• contour shape data 50 that shows a shape that is closer to the contour shape of the actual tire 30.
• the processing device 10 may detect multiple groove 40 candidates based on the contour shape data 50 generated based on the output data of the distance measurement sensor 21, select a first groove 40 that is the deepest among the multiple groove 40 candidates, and detect a groove 40 among the multiple groove 40 candidates whose depth differs from the depth of the first groove 40 by within a first predetermined value as the main groove 41.
• 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 sensor 21 is a second predetermined value A1 as the position of the starting edge portion B[n] of the groove 40, and estimate the position where the decrease in distance indicated by the output data is a third predetermined value A2 as the position of the terminal edge portion C[n] of the groove 40.
• 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 average value and the distance at the position where the distance between the starting edge portion and the ending edge portion is the greatest.
• the distance sensor 21 may be a laser distance sensor.
• 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.
• the quality of the corrected contour shape data 50 can be easily estimated.
• a tire groove measurement system 100 is a tire groove measurement system 100 that measures grooves 40 provided 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 for detecting the distance between the tire 30 and the tire groove measurement device 1, and a processing device 10, 110 for generating 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 the multiple main grooves 41 based on the contour shape data 50, deletes the data of 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 of the multiple main grooves 41 has been deleted, generates trajectory data 51 indicating the trajectory of the 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 of the multiple main grooves 41 was deleted.
• 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.
• trajectory data 51 indicating the trajectory of the movement of the tire groove measuring device 1 is generated based on the contour shape data 50 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.
• the contour shape data 50 is used to generate camera shake component data 53.
• 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.
• the quality of the corrected contour shape data 50 can be easily estimated.
• a tire groove measuring method is a tire groove measuring 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 a 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 measurement device 1 using the distance measurement sensor 21, generating contour shape data 50 indicating the contour shape of the tire 30 based on the output data of the distance measurement sensor 21, detecting the main grooves 41 based on the contour shape data 50, deleting data of the main grooves 41 from the contour shape data 50, interpolating the deleted main grooves 41 from the contour shape data 50 from which the data of the main grooves 41 has been deleted, generating trajectory data 51 indicating the trajectory of the movement of the tire groove measurement device 1, comparing the trajectory data 51 with reference shape data 52 indicating the contour shape of the tire 30 that is a reference prepared in advance, generating camera shake component data 53 indicating camera shake components, and correcting the contour shape data 50 before deleting the data of the main grooves 41 using the camera shake component data 53.
• 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.
• trajectory data 51 indicating the trajectory of the movement of the tire groove measuring device 1 is generated based on the contour shape data 50 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.
• the contour shape data 50 is used to generate camera shake component data 53.
• 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.
• the quality of the corrected contour shape data 50 can be easily estimated.
• the present invention is particularly useful in the technical field of measuring tire grooves.
• 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: Minor groove, 44: Slip sign, 50: Contour shape data, 51: Trajectory data, 52: Reference shape data, 53: Hand vibration component data, 100: Tire groove measuring system, 101: External device, 110: Processing device, 111: Processor, 112: ROM, 113: RAM, 125: Communication device

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• Length Measuring Devices By Optical Means (AREA)
• Length Measuring Devices With Unspecified Measuring Means (AREA)

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• 2022
  • 2022-10-31 JP JP2024553940A patent/JP7723216B2/ja active Active
  • 2022-10-31 WO PCT/JP2022/040676 patent/WO2024095315A1/ja not_active Ceased

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