Method and system for detecting wear uniformity after running-in of tire

Abstract

The invention belongs to the technical field of tire testing, and provides a method and system for detecting wear uniformity of a tire after running-in, and the method comprises the steps: carrying out the first outer contour scanning and first impression test on a to-be-tested tire inflated to a set air pressure, and obtaining a first outer contour scanning result and first impression test results of two set measurement positions; carrying out a walking test on the to-be-tested tire according to set condition parameters, and then carrying out secondary outer contour scanning to obtain a second outer contour scanning result; performing a secondary impression test on the to-be-tested tire after the running test to obtain a second impression test result; determining a growth range difference value, an average rectangularity rate and a residual pattern range of the to-be-detected tire; and taking the growth amplitude difference, the average rectangularity and the residual pattern range as wear uniformity evaluation indexes, and performing wear uniformity evaluation on the to-be-detected tire after running-in to obtain a wear uniformity detection result. According to the scheme provided by the invention, the detection precision and the detection efficiency of the wear uniformity detection link are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of tire testing, and in particular to a method and system for detecting wear uniformity of a tire after running-in. Background Art

[0002] As a key load-bearing component of a vehicle, tire performance degradation is closely related to changes in its internal structure. Over long-term use, tire rubber material undergoes significant aging and degradation of its elastic modulus due to factors such as temperature, load, and environmental media. Simultaneously, structural materials such as tire cord and fabric experience angular creep due to continuous alternating loads. This time-varying behavior of material properties leads to progressive deformation of the tire's internal profile, manifesting as expansion of the bead diameter and changes in the curvature of the carcass cord layer. This, in turn, affects the tire's ground contact pressure distribution, wear uniformity, and high-speed stability.

[0003] In related technologies, the evaluation of tire wear uniformity after running-in usually relies on full-size running tests, which involve performing load tests for tens of thousands of kilometers on actual roads or test benches. The test cycle is long, and the wear uniformity evaluation is subsequently achieved by synchronously collecting three-dimensional data of the tire's outer contour and then inferring the deformation of the inner contour. The data processing process is complex and it is difficult to ensure detection accuracy.

[0004] Therefore, the traditional tire wear uniformity detection scheme after running-in has technical problems such as low detection efficiency and insufficient detection accuracy. Summary of the Invention

[0005] The present invention provides a method and system for detecting wear uniformity of tires after running-in, which are used to solve the defects of low detection efficiency and insufficient detection accuracy of traditional wear uniformity detection schemes after running-in of tires.

[0006] In one aspect, the present invention provides a method for detecting wear uniformity of a tire after running-in, comprising: Performing a first outer contour scan on the tire to be tested, which is inflated to a set pressure, and performing a first footprint test on the tire to be tested, to obtain a first outer contour scan result and first footprint test results at two set measurement positions; wherein the angle difference between the two set measurement positions is 90 degrees; Performing a running test on the tire to be tested according to set condition parameters, and performing a second outer contour scan on the tire to be tested that is inflated to the set air pressure after the running test to obtain a second outer contour scan result; Perform a second footprint test on the tire to be tested after the running test to obtain the second footprint test results at two set measurement positions; Determining a growth amplitude difference, an average rectangularity, and a remaining pattern range of the tire to be tested based on at least part of the first outer contour scanning result, the first footprint test result, the second outer contour scanning result, and the second footprint test result; The growth amplitude difference, average rectangularity and remaining pattern extreme difference are used as wear uniformity evaluation indicators, and the wear uniformity of the tire to be tested is evaluated after running-in to obtain a wear uniformity test result.

[0007] According to the method for detecting wear uniformity of a tire after running-in provided by the present invention, the first outer contour scanning result includes: initial radial data of the tire shoulder and initial radial data of the tire crown; the second outer contour scanning result includes: final radial data of the tire shoulder and final radial data of the tire crown; Determining the growth amplitude difference of the tire to be tested based on the first outer contour scanning result and the second outer contour scanning result includes: The difference between the final shoulder radial data and the initial shoulder radial data is divided by the initial shoulder radial data to obtain a shoulder growth amplitude value; The difference between the final radial data of the crown and the initial radial data of the crown is divided by the initial radial data of the crown to obtain the growth amplitude value of the crown; The growth amplitude difference of the tire to be tested is calculated by subtracting the shoulder growth amplitude value from the crown growth amplitude value and finding the absolute value.

[0008] According to the method for detecting wear uniformity of a tire after running-in provided by the present invention, the first footprint test result includes: the initial length of the outer shoulder, the initial length of the inner shoulder, and the initial contact length corresponding to two set measurement positions; the second footprint test result includes: the final length of the outer shoulder, the final length of the inner shoulder, and the final contact length corresponding to two set measurement positions; Determining an average rectangular ratio of the tire to be tested based on the first footprint test result and the second footprint test result, including: Calculating a first initial rectangular ratio and a second initial rectangular ratio at the two set measurement positions based on the outer shoulder initial length, the inner shoulder initial length, and the initial contact length corresponding to the two set measurement positions; Calculating a first final rectangular ratio and a second final rectangular ratio at the two set measurement positions based on the final outer shoulder length, the final inner shoulder length, and the final contact length corresponding to the two set measurement positions; An average rectangular ratio of the tire to be tested is determined according to the first initial rectangular ratio, the second initial rectangular ratio, the first final rectangular ratio, and the second final rectangular ratio.

[0009] According to the method for detecting tire wear uniformity after tire running-in provided by the present invention, a first initial rectangular ratio is calculated based on an initial length of an outer shoulder, an initial length of an inner shoulder, and an initial contact length, including: Adding the initial length of the outer shoulder to the initial length of the inner shoulder to obtain a sum of shoulder lengths; The first initial rectangular ratio is obtained by dividing the sum of the shoulder lengths by twice the initial contact length.

[0010] According to the method for detecting tire wear uniformity after tire running-in provided by the present invention, the second outer contour scanning result includes tread depth data of each wheel position; Determining the remaining tread range of the tire to be tested based on the second outer contour scanning result includes: Determining the maximum and minimum tread depths corresponding to the respective wheel positions based on the tread depth data of the respective wheel positions; The maximum and minimum tread depths corresponding to each wheel position are subtracted to obtain the range of tread depths corresponding to each wheel position. Determine the target tread depth range with the largest value among the tread depth ranges corresponding to each wheel position as the remaining tread range of the tire to be tested.

[0011] According to the method for detecting wear uniformity of a tire after running-in provided by the present invention, the growth amplitude difference, the average rectangularity, and the residual pattern range are used as wear uniformity evaluation indicators, and the wear uniformity of the tire to be tested is evaluated after running-in to obtain a wear uniformity test result, including: Determine whether the growth amplitude difference is less than a preset amplitude difference threshold, and obtain a first determination result; Determine whether the average rectangular ratio is higher than a preset rectangular ratio threshold, and obtain a second determination result; Determine whether the remaining pattern range is less than a preset pattern range threshold, and obtain a third determination result; A wear evenness detection result is determined based on the first judgment result, the second judgment result, and the third judgment result.

[0012] According to the method for detecting wear uniformity of a tire after running-in provided by the present invention, determining a wear uniformity detection result based on the first judgment result, the second judgment result, and the third judgment result includes: If the first judgment result, the second judgment result, and the third judgment result are all yes, determining that the wear evenness test result is normal; If at least one of the first judgment result, the second judgment result, and the third judgment result is negative, the wear evenness detection result is determined to be abnormal wear evenness.

[0013] According to the method for detecting wear uniformity of a tire after running-in provided by the present invention, after obtaining the wear uniformity detection result, the method further includes: Acquire an initial contact image of the tire under test before the running test and a final contact image after the running test; performing image feature comparison between the initial grounding image and the final grounding image, and determining a region of interest based on the image feature comparison result; intercepting an image of the area to be inspected corresponding to the area of ​​interest in the final ground image; The image of the area to be inspected is input into a pre-built wear evenness diagnosis model to obtain wear root cause information output by the wear evenness diagnosis model.

[0014] According to the method for detecting tire wear uniformity after tire running-in provided by the present invention, determining a region of interest based on image feature comparison results includes: Determine a target image point whose absolute value of a pixel difference in the image feature comparison result is higher than a preset pixel difference threshold; A minimum image area including all target image points is determined, and the minimum image area is used as a region of interest.

[0015] In another aspect, the present invention further provides a system for detecting tire wear uniformity after tire running-in, comprising: a first acquisition module, configured to perform a first outer contour scan of the tire to be tested, which is inflated to a set pressure, and to perform a first footprint test on the tire to be tested, thereby obtaining a first outer contour scan result and first footprint test results at two set measurement locations; wherein the angle difference between the two set measurement locations is 90 degrees; A secondary scanning module is used to perform a running test on the tire to be tested according to set condition parameters, and perform a secondary outer contour scan on the tire to be tested that is inflated to the set air pressure after the running test to obtain a second outer contour scan result; A secondary test module is used to perform a secondary footprint test on the tire to be tested after the running test, and obtain the second footprint test results at two set measurement positions; a processing module, configured to determine a growth amplitude difference, an average rectangularity, and a remaining pattern range of the tire to be tested based on at least part of the first outer contour scanning result, the first footprint test result, the second outer contour scanning result, and the second footprint test result; The detection module is used to use the growth amplitude difference, average rectangularity and remaining pattern extreme difference as wear uniformity evaluation indicators to evaluate the wear uniformity of the tire to be tested after running-in, and obtain a wear uniformity detection result.

[0016] The present invention provides a method and system for detecting the wear uniformity of tires after running-in. The method and system perform a first outer contour scan on a tire to be tested that is inflated to a set pressure, and a first footprint test on the tire to be tested, to obtain a first outer contour scan result and a first footprint test result at two set measurement positions with an angle difference of 90 degrees; a running test is performed on the tire to be tested according to set condition parameters, and a second outer contour scan is performed on the tire to be tested that is inflated to a set pressure after the running test, to obtain a second outer contour scan result; a second footprint test is performed on the tire to be tested after the running test, to obtain a second footprint test result at two set measurement positions; based on at least part of the data in the first outer contour scan result, the first footprint test result, the second outer contour scan result, and the second footprint test result, the growth amplitude difference, average rectangular rate, and remaining pattern extreme difference of the tire to be tested are determined; the growth amplitude difference, average rectangular rate, and remaining pattern extreme difference are used as wear uniformity evaluation indicators, and the wear uniformity of the tire to be tested after running-in is evaluated to obtain a wear uniformity detection result. Since the detection process can determine the wear uniformity evaluation indicators such as the growth amplitude difference, average rectangular rate and remaining pattern extreme value of the tire to be tested based on the outer contour scanning data and footprint test data before and after the running test, it can achieve accurate and rapid evaluation of the wear uniformity of the tire to be tested after running-in, thereby improving the detection accuracy and efficiency of the wear uniformity detection process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 1 is a flow chart of a method for detecting tire wear uniformity after tire running-in, provided by an embodiment of the present invention; Figure 2 It is a schematic diagram of the outer contour state of the tire under test before and after the running test; Figure 3 This is a schematic diagram of the outer contour of a new tire and one after 70,000 kilometers of use, showing abnormal wear caused by uneven growth of the inner contour of the tire. Figure 4 is the imprint image obtained by the imprint test; Figure 5 1 is a schematic structural diagram of a system for detecting tire wear uniformity after tire running-in provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0019] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0020] The following combination Figures 1 to 5 The following describes the detailed scheme of the method and system for detecting tire wear uniformity after tire running-in provided by an embodiment of the present invention.

[0021] Figure 1 4 is a flow chart of a method for detecting tire wear uniformity after tire running-in provided by an embodiment of the present invention.

[0022] like Figure 1 As shown, the method for detecting tire wear uniformity after tire running-in provided by an embodiment of the present invention mainly includes the following steps: Step 110: Perform a first outer contour scan on the tire to be tested, which is inflated to a set pressure, and perform a first footprint test on the tire to be tested, to obtain a first outer contour scan result and first footprint test results at two set measurement positions; wherein the angle difference between the two set measurement positions is 90 degrees.

[0023] It can be understood that when the first footprint test is performed on the tire to be tested that is inflated to the set air pressure according to the standard load, the test results of two set measurement positions can be collected, that is, the first footprint test results. The angle difference between the two set measurement positions is set to 90 degrees, which can eliminate the influence of the bead ovality on the footprint.

[0024] In this embodiment, the set air pressure can be the air pressure value commonly used by the user, and the outer contour scanning can use high-precision optical or laser measuring equipment to quickly collect three-dimensional data of the geometric features of important external parts of the tire, such as the tread, sidewall, and bead.

[0025] Step 120 : performing a running test on the tire to be tested according to the set condition parameters, and performing a second outer contour scan on the tire to be tested that is inflated to the set air pressure after the running test to obtain a second outer contour scan result.

[0026] In this embodiment, the setting condition parameters used in the running test include inflation pressure, running load, driving speed and mileage, among which the inflation pressure can be set to 1000kPa, the running load can be set to 85% load, the driving speed can be set to 50km / h, and the mileage can be set to 3000km.

[0027] Figure 2The outer contour scanning results of the tire to be tested before and after the running test are shown as an example, wherein 210 represents the outer contour state of the tire to be tested before the running test, 220 represents the outer contour state of the tire to be tested after the running test, and 230 represents the carcass turn-up end point. After the running test, the carcass turn-up end point is expanded and concave.

[0028] Figure 3 The following example shows the corresponding outer contour scanning results of a new tire and a tire after 70,000 kilometers of use with abnormal wear caused by uneven inner contour growth. 310 represents the outer contour state of a new tire, and 320 represents the outer contour state of a tire after 70,000 kilometers of use with abnormal wear caused by uneven inner contour growth. Figure 3 It can be seen that after 70,000 kilometers of use, the inner contour radius of the crown of the new tire has grown by about 2.4mm. The difference in growth between the tire shoulder and the crown is more than 1mm, which has caused abnormal wear in the driving wheel crown. The extreme wear difference is more than 4mm, and there is serious abnormal wear.

[0029] Step 130: Perform a second footprint test on the tire to be tested after the running test to obtain second footprint test results at two set measurement positions.

[0030] Figure 4 The footprint image obtained by the footprint test is shown as an example, wherein CL represents the contact length of the footprint center, w represents the contact width of the footprint, OSL represents the outer shoulder length of the footprint at 80% of the contact width, and ISL represents the inner shoulder length of the footprint at 80% of the contact width.

[0031] Step 140: Determine the growth amplitude difference, average rectangularity, and remaining pattern range of the tire to be tested based on at least part of the first outer contour scanning result, the first footprint test result, the second outer contour scanning result, and the second footprint test result.

[0032] It can be understood that the growth amplitude difference of the tire to be tested can represent the difference between the shoulder growth amplitude value and the crown growth amplitude value of the tire to be tested, the average rectangular rate is used to represent the degree to which the area of ​​the tire to be tested in contact with the ground is closer to a rectangle, and the remaining pattern range is used to represent the maximum difference between the remaining pattern depths at different positions on the tread of the tire to be tested.

[0033] Step 150: Using the growth amplitude difference, the average rectangularity, and the remaining pattern range as wear uniformity evaluation indicators, the wear uniformity of the tire to be tested is evaluated after running-in to obtain a wear uniformity test result.

[0034] The solution provided in this embodiment, by using the growth amplitude difference, average rectangularity, and remaining pattern extreme difference as wear uniformity evaluation indicators, can conveniently achieve a comprehensive evaluation of the wear uniformity of the tire under test after running-in, thereby obtaining wear uniformity test results with more reference value, and improving the detection accuracy and efficiency of the wear uniformity detection link.

[0035] In one embodiment, the first outer contour scanning result includes: initial radial data of the tire shoulder and initial radial data of the crown; the second outer contour scanning result includes: final radial data of the tire shoulder and final radial data of the crown.

[0036] Furthermore, determining the growth amplitude difference of the tire to be tested based on the first outer contour scanning result and the second outer contour scanning result includes: First, the difference between the final shoulder radial data and the initial shoulder radial data is divided by the initial shoulder radial data to obtain the shoulder growth amplitude value.

[0037] It's understood that the shoulder refers to the transition area between the tread and the sidewall, i.e., the crown edge. The initial and final shoulder radial data can be either shoulder height or tire width. The shoulder growth amplitude value represents the radial dimensional increase in the shoulder area of ​​the tire being tested after the running test, typically manifesting as an increase in tire width or thickness. This is primarily due to factors such as tire compression, material expansion due to heating, or structural deformation (such as cord stretching).

[0038] Then, the difference between the final radial data in the crown and the initial radial data in the crown is divided by the initial radial data in the crown to obtain the growth amplitude value in the crown.

[0039] It's understood that crown center primarily refers to the crown center of the tire under test, i.e., the widest point of the tread. The initial and final radial crown center values ​​can be crown center height or tread radius. The crown center growth amplitude value represents the radial increase in the crown center of the tire under test after the running test, typically manifesting as a change in tire height or tread radius. This is primarily due to the crown center directly bearing loads and friction, resulting in more concentrated deformation.

[0040] Finally, the shoulder growth amplitude value is subtracted from the crown growth amplitude value and the absolute value is calculated to obtain the growth amplitude difference of the tire to be tested.

[0041] It is understood that if the shoulder growth amplitude value is greater than the crown growth amplitude value, it means that the shoulder deformation is more significant, which may be related to sidewall flexibility or edge load distribution. If the crown growth amplitude value is greater than the shoulder growth amplitude value, it means that the crown deformation is more significant, which may be related to tread rigidity or center ground pressure concentration.

[0042] In one embodiment, the first footprint test result specifically includes: the initial length of the outer shoulder, the initial length of the inner shoulder, and the initial contact length corresponding to the two set measurement positions; the second footprint test result specifically includes: the final length of the outer shoulder, the final length of the inner shoulder, and the final contact length corresponding to the two set measurement positions.

[0043] Furthermore, the average rectangular ratio of the tire to be tested is determined based on the first footprint test result and the second footprint test result, specifically including: First, based on the outer shoulder initial length, inner shoulder initial length and initial contact length corresponding to the two set measurement positions, the first initial rectangular ratio and the second initial rectangular ratio of the two set measurement positions are calculated.

[0044] Then, based on the outer shoulder final length, inner shoulder final length and final contact length corresponding to the two set measurement positions, the first final rectangular ratio and the second final rectangular ratio of the two set measurement positions are calculated.

[0045] In practical applications, the first and second footprint test results at two set measurement locations can be presented in a table format. The two set measurement locations are the DOT 180-degree position and the DOT 90-degree position. Both the first and second footprint test results include key information such as contact patch length (degrees), contact patch width (degrees), effective contact patch area, total contact patch area, outer shoulder length (degrees), outer shoulder width (degrees), rectangularity, and contact patch image (i.e., footprint image). The footprint test results obtained before and after a certain running test can be seen in Table 1 below.

[0046] Table 1 Imprint test results

[0047] Finally, the average rectangular ratio of the tire to be tested is determined according to the first initial rectangular ratio, the second initial rectangular ratio, the first final rectangular ratio, and the second final rectangular ratio.

[0048] In this embodiment, the average rectangular ratio of the tire to be tested can be the minimum value among the first initial rectangular ratio, the second initial rectangular ratio, the first final rectangular ratio and the second final rectangular ratio, or the average rectangular ratio of the tire to be tested can be the average value of the first initial rectangular ratio, the second initial rectangular ratio, the first final rectangular ratio and the second final rectangular ratio.

[0049] In one embodiment, the first initial rectangular ratio is calculated based on the initial length of the outer shoulder, the initial length of the inner shoulder, and the initial contact length, including: Add the initial length of the outer shoulder to the initial length of the inner shoulder to obtain the sum of the shoulder lengths; The first initial rectangular ratio is obtained by dividing the sum of the shoulder lengths by twice the initial contact length.

[0050] In this embodiment, the rectangular ratio can be calculated using the following formula: (1); Among them, FSF represents the rectangular ratio, such as the first initial rectangular ratio or the first final rectangular ratio; OSL represents the outer shoulder length, such as the outer shoulder initial length or the outer shoulder final length; ISL represents the inner shoulder length, such as the inner shoulder initial length or the inner shoulder final length; CL represents the contact length, such as the initial contact length or the final contact length.

[0051] In one embodiment, the second outer contour scanning result specifically includes tread depth data of each wheel position.

[0052] Furthermore, the remaining tread range of the tire to be tested is determined based on the second outer contour scanning result, including: First, based on the tread depth data of each wheel position, the maximum tread depth and the minimum tread depth corresponding to each wheel position are determined respectively.

[0053] Then, the maximum and minimum tread depths corresponding to each wheel position are subtracted to obtain the range of tread depths corresponding to each wheel position.

[0054] Finally, the target tread depth range with the largest value among the tread depth ranges corresponding to each wheel position is determined as the remaining tread depth range of the tire to be tested.

[0055] Key data such as the tread depth and tread depth range at different wheel positions of the tested tire after a certain test can be found in Table 2 below.

[0056] Table 2 Tread depth and tread depth range data for different wheel positions

[0057] In one embodiment, the growth amplitude difference, average rectangularity, and residual pattern extreme value are used as wear uniformity evaluation indicators to evaluate the wear uniformity of the tire after running-in, and the wear uniformity test results obtained include: On the one hand, it is determined whether the growth amplitude difference is less than a preset amplitude difference threshold to obtain a first determination result.

[0058] In this embodiment, the preset amplitude difference threshold may be set to 1 mm. That is, when the growth amplitude difference is less than 1 mm, it preliminarily indicates that the tire to be tested has no abnormal wear defects.

[0059] On the other hand, it is determined whether the average rectangular ratio is higher than a preset rectangular ratio threshold to obtain a second determination result.

[0060] In this embodiment, the preset rectangular ratio threshold may be set to 0.86. That is, when the average rectangular ratio is higher than 0.86, it preliminarily indicates that the tire to be tested has no abnormal wear defects.

[0061] On the other hand, it is determined whether the remaining pattern range is less than a preset pattern range threshold to obtain a third judgment result.

[0062] In this embodiment, the preset pattern range threshold can be set to 1 mm. That is, when the remaining pattern range is less than 1 mm, it preliminarily indicates that the tire to be tested has no abnormal wear defects.

[0063] Finally, the wear evenness test result is determined based on the first judgment result, the second judgment result, and the third judgment result.

[0064] In a specific implementation, determining the wear evenness test result based on the first judgment result, the second judgment result, and the third judgment result specifically includes: If the first judgment result, the second judgment result, and the third judgment result are all yes, then the wear evenness test result is determined to be normal.

[0065] That is to say, if the above three judgment results are all yes, it can be finally concluded that the tire under test has no abnormal wear defects, and it can be determined that the wear uniformity of the tire under test is normal.

[0066] If at least one of the first judgment result, the second judgment result, and the third judgment result is negative, the wear evenness detection result is determined to be abnormal wear evenness.

[0067] It is understandable that if one or more of the above three judgment results is negative, it means that the tire under test has abnormal wear defects of varying degrees, and it can be determined that the wear uniformity of the tire under test is abnormal.

[0068] In one embodiment, after obtaining the wear evenness test result, the method may further include: In the first step, an initial contact image of the tire under test before the running test and a final contact image after the running test are obtained.

[0069] In practical applications, the initial ground contact image and the final ground contact image can be obtained through a footprint test before and after the running test.

[0070] In the second step, the initial ground image and the final ground image are compared for image features, and the region of interest is determined based on the image feature comparison results.

[0071] In a specific implementation, determining the region of interest based on the image feature comparison result specifically includes: First, target image points whose absolute values ​​of pixel differences in the image feature comparison results are higher than a preset pixel difference threshold are determined.

[0072] In this embodiment, the pixel values ​​between the image points at the same position in the initial ground image and the final ground image can be compared. Specifically, the pixel values ​​between the image points at the same position can be subtracted, and the absolute value of the pixel difference can be used as the image feature comparison result.

[0073] It can be understood that the higher the absolute value of the pixel difference, the greater the difference between the two image points at the same position, and the greater the possibility of an abnormality at that position. Therefore, this embodiment extracts target image points whose absolute value of the pixel difference is higher than the preset pixel difference threshold.

[0074] Then, the minimum image area containing all target image points is determined, and the minimum image area is used as the region of interest.

[0075] In practical applications, the minimum enclosing geometric shape that contains all target image points can be calculated, such as the minimum enclosing rectangle, the minimum enclosing circle, or the minimum convex hull, to obtain the minimum image area.

[0076] The third step is to intercept the image of the area to be inspected corresponding to the area of ​​interest in the final ground image.

[0077] In this embodiment, by cutting out the region of interest and subsequently analyzing the region of interest separately, the amount of subsequent data analysis can be reduced, thereby improving the efficiency of wear uniformity diagnosis.

[0078] In the fourth step, the image of the area to be inspected is input into the pre-built wear uniformity diagnosis model to obtain the wear root cause information output by the wear uniformity diagnosis model.

[0079] In this embodiment, contact patch images of different tire models under varying wear conditions are acquired. Abnormal wear areas are captured from each contact patch image, and wear root cause labels are annotated within these areas. This yields multiple image samples with wear root cause labels. Subsequently, a deep learning network model is trained and tested using these image samples to develop a wear uniformity diagnostic model.

[0080] It is understandable that different wear conditions are usually manifested as different wear degrees and different wear types, and the wear types may include eccentric wear, center wear, and feather wear.

[0081] In practical applications, wear root cause information usually includes various root cause information such as abnormal wheel alignment, abnormal tire pressure, and wheel hub deformation.

[0082] In some embodiments, before inputting the image of the area to be inspected into a pre-built wear uniformity diagnosis model, the image of the area to be inspected can be filtered, such as by using median filtering or Gaussian filtering to remove noise points in the image of the area to be inspected, thereby further improving the diagnostic accuracy of the model.

[0083] In some embodiments, a wear root cause-solution strategy database can be established to store the correspondence between wear root cause information and corresponding solution strategies. For example, the solution strategy corresponding to abnormal wheel alignment is four-wheel alignment calibration, the solution strategy corresponding to abnormal tire pressure is calibrating the tire pressure to the standard value, and the solution strategy corresponding to wheel hub deformation is replacing or repairing the wheel hub, thereby providing data basis for subsequent wear diagnosis analysis and problem solving.

[0084] Based on the same general inventive concept, the present invention also protects a system for detecting the uniformity of tire wear after running-in. The system for detecting the uniformity of tire wear after running-in provided by the present invention is described below. The system for detecting the uniformity of tire wear after running-in described below and the method for detecting the uniformity of tire wear after running-in described above can be referenced to each other.

[0085] Figure 5 1 is a schematic structural diagram of a system for detecting tire wear uniformity after tire running-in provided by an embodiment of the present invention.

[0086] like Figure 5 As shown, the system for detecting tire wear uniformity after tire running-in provided by an embodiment of the present invention specifically includes: The first acquisition module 410 is used to perform a first outer contour scan on the tire to be tested that is inflated to a set pressure, and to perform a first footprint test on the tire to be tested, thereby obtaining a first outer contour scan result and first footprint test results at two set measurement positions; wherein the angular difference between the two set measurement positions is 90 degrees.

[0087] The secondary scanning module 420 is used to perform a running test on the tire to be tested according to set condition parameters, and perform a secondary outer contour scan on the tire to be tested that is inflated to the set air pressure after the running test to obtain a second outer contour scan result.

[0088] The secondary test module 430 is used to perform a secondary footprint test on the tire to be tested after the running test, and obtain the second footprint test results at two set measurement positions.

[0089] The processing module 440 is used to determine the growth amplitude difference, average rectangularity and remaining pattern range of the tire to be tested based on at least part of the first outer contour scanning result, the first footprint test result, the second outer contour scanning result and the second footprint test result.

[0090] The detection module 450 is used to use the growth amplitude difference, the average rectangular rate and the residual pattern range as wear uniformity evaluation indicators to evaluate the wear uniformity of the tire after running-in and obtain a wear uniformity detection result.

[0091] Regarding the system in the above embodiment, the specific manner in which each module performs operations has been described in detail in the embodiment of the method, and will not be elaborated again here.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for detecting tire wear uniformity after tire running-in, characterized in that: include: Performing a first outer contour scan on the tire to be tested, which is inflated to a set pressure, and performing a first footprint test on the tire to be tested, to obtain a first outer contour scan result and first footprint test results at two set measurement positions; wherein the angle difference between the two set measurement positions is 90 degrees; Performing a running test on the tire to be tested according to set condition parameters, and performing a second outer contour scan on the tire to be tested that is inflated to the set air pressure after the running test to obtain a second outer contour scan result; Perform a second footprint test on the tire to be tested after the running test to obtain the second footprint test results at two set measurement positions; Determining a growth amplitude difference, an average rectangularity, and a remaining pattern range of the tire to be tested based on at least part of the first outer contour scanning result, the first footprint test result, the second outer contour scanning result, and the second footprint test result; The growth amplitude difference, average rectangularity and remaining pattern extreme difference are used as wear uniformity evaluation indicators, and the wear uniformity of the tire to be tested is evaluated after running-in to obtain a wear uniformity test result.

2. The method for detecting tire wear uniformity after tire running-in according to claim 1, characterized in that: The first outer contour scanning result includes: initial radial data of the tire shoulder and initial radial data of the crown; the second outer contour scanning result includes: final radial data of the tire shoulder and final radial data of the crown; Determining the growth amplitude difference of the tire to be tested based on the first outer contour scanning result and the second outer contour scanning result includes: The difference between the final shoulder radial data and the initial shoulder radial data is divided by the initial shoulder radial data to obtain a shoulder growth amplitude value; The difference between the final radial data of the crown and the initial radial data of the crown is divided by the initial radial data of the crown to obtain the growth amplitude value of the crown; The growth amplitude difference of the tire to be tested is calculated by subtracting the shoulder growth amplitude value from the crown growth amplitude value and finding the absolute value.

3. The method for detecting tire wear uniformity after tire running-in according to claim 1, characterized in that: The first footprint test result includes: the initial length of the outer shoulder, the initial length of the inner shoulder, and the initial contact length corresponding to the two set measurement positions; the second footprint test result includes: the final length of the outer shoulder, the final length of the inner shoulder, and the final contact length corresponding to the two set measurement positions; Determining an average rectangular ratio of the tire to be tested based on the first footprint test result and the second footprint test result, including: Calculating a first initial rectangular ratio and a second initial rectangular ratio at the two set measurement positions based on the outer shoulder initial length, the inner shoulder initial length, and the initial contact length corresponding to the two set measurement positions; Calculating a first final rectangular ratio and a second final rectangular ratio at the two set measurement positions based on the final outer shoulder length, the final inner shoulder length, and the final contact length corresponding to the two set measurement positions; An average rectangular ratio of the tire to be tested is determined according to the first initial rectangular ratio, the second initial rectangular ratio, the first final rectangular ratio, and the second final rectangular ratio.

4. The method for detecting tire wear uniformity after tire running-in according to claim 3, characterized in that: Based on the initial length of the outer shoulder, the initial length of the inner shoulder, and the initial contact length, a first initial rectangular ratio is calculated, including: Adding the initial length of the outer shoulder to the initial length of the inner shoulder to obtain a sum of shoulder lengths; The first initial rectangular ratio is obtained by dividing the sum of the shoulder lengths by twice the initial contact length.

5. The method for detecting tire wear uniformity after tire running-in according to claim 1, characterized in that: The second outer contour scanning result includes the tread depth data of each wheel position; Determining the remaining tread range of the tire to be tested based on the second outer contour scanning result includes: Determining the maximum and minimum tread depths corresponding to the respective wheel positions based on the tread depth data of the respective wheel positions; The maximum and minimum tread depths corresponding to each wheel position are subtracted to obtain the range of tread depths corresponding to each wheel position. Determine the target tread depth range with the largest value among the tread depth ranges corresponding to each wheel position as the remaining tread range of the tire to be tested.

6. The method for detecting tire wear uniformity after tire running-in according to claim 1, characterized in that: The growth amplitude difference, average rectangularity, and remaining pattern extreme difference are used as wear uniformity evaluation indicators to evaluate the wear uniformity of the tire to be tested after running-in, and the wear uniformity test results are obtained, including: Determine whether the growth amplitude difference is less than a preset amplitude difference threshold, and obtain a first determination result; Determine whether the average rectangular ratio is higher than a preset rectangular ratio threshold, and obtain a second determination result; Determine whether the remaining pattern range is less than a preset pattern range threshold, and obtain a third determination result; A wear evenness detection result is determined based on the first judgment result, the second judgment result, and the third judgment result.

7. The method for detecting tire wear uniformity after tire running-in according to claim 6, characterized in that: Determining a wear evenness test result based on the first judgment result, the second judgment result, and the third judgment result includes: If the first judgment result, the second judgment result, and the third judgment result are all yes, determining that the wear evenness test result is normal; If at least one of the first judgment result, the second judgment result, and the third judgment result is negative, the wear evenness detection result is determined to be abnormal wear evenness.

8. The method for detecting tire wear uniformity after tire running-in according to claim 1, characterized in that: After obtaining the wear uniformity test result, the method further includes: Acquire an initial contact image of the tire under test before the running test and a final contact image after the running test; performing image feature comparison between the initial grounding image and the final grounding image, and determining a region of interest based on the image feature comparison result; intercepting an image of the area to be inspected corresponding to the area of ​​interest in the final ground image; The image of the area to be inspected is input into a pre-built wear evenness diagnosis model to obtain wear root cause information output by the wear evenness diagnosis model.

9. The method for detecting tire wear uniformity after tire running-in according to claim 8, characterized in that: Determine the region of interest based on the image feature comparison results, including: Determine a target image point whose absolute value of a pixel difference in the image feature comparison result is higher than a preset pixel difference threshold; A minimum image area including all target image points is determined, and the minimum image area is used as a region of interest.

10. A system for detecting tire wear uniformity after tire running-in, characterized in that: include: a first acquisition module, configured to perform a first outer contour scan of the tire to be tested, which is inflated to a set pressure, and to perform a first footprint test on the tire to be tested, thereby obtaining a first outer contour scan result and first footprint test results at two set measurement locations; wherein the angle difference between the two set measurement locations is 90 degrees; A secondary scanning module is used to perform a running test on the tire to be tested according to set condition parameters, and perform a secondary outer contour scan on the tire to be tested that is inflated to the set air pressure after the running test to obtain a second outer contour scan result; A secondary test module is used to perform a secondary footprint test on the tire to be tested after the running test, and obtain the second footprint test results at two set measurement positions; a processing module, configured to determine a growth amplitude difference, an average rectangularity, and a remaining pattern range of the tire to be tested based on at least part of the first outer contour scanning result, the first footprint test result, the second outer contour scanning result, and the second footprint test result; The detection module is used to use the growth amplitude difference, average rectangularity and remaining pattern extreme difference as wear uniformity evaluation indicators to evaluate the wear uniformity of the tire to be tested after running-in, and obtain a wear uniformity detection result.

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