A method, system and device for measuring yarn twist

Abstract

The present invention relates to the field of textile measurement technology, and specifically to a yarn twist measurement method, measurement system and device. The present invention first obtains the length variable sequence corresponding to the untwisting process and twisting process of the test sample according to the change characteristics of the yarn length value in the untwisting process and the twisting process of the test sample; obtains all deformation amplitudes of the test sample according to the value changes in the neighborhood reference range of the length variables in the untwisting process and the twisting process of the test sample; corrects the pre-tension value according to all deformation amplitudes of all test samples of the test yarn, and obtains the corrected pre-tension value of the test yarn. The present invention conducts an in-depth analysis of the uneven distribution of the thickness of the test yarn, reasonably sets the corrected pre-tension value, and improves the accuracy of the yarn twist test result.

Description

Technical Field

[0001] The invention relates to the technical field of textile measurement, and in particular to a yarn twist measurement method, a measurement system and a device. Background Art

[0002] Yarn twist refers to the number of twists per unit length of yarn, that is, the spiral structure formed by the axial twisting of fibers or tows during the twisting process. The measurement of yarn twist is of great significance in textile production. By testing the twist of yarn, the degree of yarn twisting can be evaluated, and then its physical and mechanical properties can be judged to meet production requirements. In the measurement of yarn twist, the yarn needs to be kept in a certain tension state to prevent the yarn from relaxing during the test and affecting the test results.

[0003] Applying a pre-tension value to the yarn can ensure the stability and consistency of the yarn during the test, thereby improving the accuracy of the test. In the yarn twist test, the selection of the pre-tension value has a great influence on the test results. The prior art usually determines the pre-tension value based on the yarn linear density. The pre-tension value is difficult to adapt to the yarn with uneven thickness distribution, thus affecting the accuracy of the yarn twist test results. Summary of the invention

[0004] In order to solve the technical problem that the pre-tension value is inaccurate in the prior art, which affects the accuracy of the yarn twist test result, the purpose of the present invention is to provide a yarn twist measurement method, measurement system and device, and the technical scheme adopted is as follows:

[0005] A method for measuring yarn twist, the method comprising:

[0006] Acquire a yarn length data set for measuring twist of a test yarn using a pre-tension value; the yarn length data set includes a sequence of yarn length values ​​corresponding to the untwisting process and the twisting process of each test sample;

[0007] According to the variation characteristics of the yarn length values ​​during the untwisting process and the twisting process of the test sample, the length variable sequence corresponding to the untwisting process and the twisting process of the test sample is obtained; according to the overall distribution of the length variables during the untwisting process and the twisting process of the test sample, the sample deformation degree of the test sample is obtained; the yarn material deformation degree of the test yarn is obtained by integrating the sample deformation degrees of all the test samples of the test yarn; according to the yarn material deformation degree, the neighborhood reference range of each length variable is determined; according to the value changes in the neighborhood reference range of the length variables during the untwisting process and the twisting process of the test sample, all deformation amplitudes of the test sample are obtained;

[0008] The pre-tension value is corrected according to all the deformation amplitudes of all the test samples of the test yarn to obtain the corrected pre-tension value of the test yarn.

[0009] Furthermore, the method for obtaining the length variable sequence includes:

[0010] For the yarn length value sequence of the test sample in the untwisting process, the difference between each yarn length value and the previous yarn length value is calculated to obtain the length variable corresponding to each yarn length value of the test sample in the untwisting process; the length variable corresponding to each yarn length value in the untwisting process is counted in sequence to obtain the length variable sequence corresponding to the untwisting process;

[0011] For the yarn length value sequence of the twisting process of the test sample, the difference between each yarn length value and the subsequent yarn length value is calculated to obtain the length variable corresponding to each yarn length value of the test sample in the twisting process; the length variables corresponding to each yarn length value in the twisting process are counted in turn to obtain the length variable sequence corresponding to the twisting process.

[0012] Furthermore, the method for obtaining the sample deformation degree includes:

[0013] Calculating the mean of all length variables of the test sample during the untwisting process to obtain an overall deformation measurement of the untwisting process;

[0014] Calculating the mean of all length variables of the test sample during the twisting process to obtain an overall deformation measurement of the twisting process;

[0015] The average of the overall deformation measure of the untwisting process and the overall deformation measure of the twisting process is calculated to obtain the sample deformation of the test sample.

[0016] Furthermore, the method for obtaining the yarn material deformation degree includes:

[0017] Taking any one of the test samples as a sample to be analyzed, calculating the variance of all the length variables of the sample to be analyzed during the untwisting process, calculating the variance of all the length variables of the sample to be analyzed during the twisting process, performing negative correlation mapping on the largest variance, and obtaining a reference weight of the sample to be analyzed;

[0018] The reference weights of all the test samples of the test yarn are used to perform weighted average calculation on the sample deformation degrees of all the test samples to obtain the yarn material deformation degree of the test yarn.

[0019] Furthermore, the method for obtaining the neighborhood reference range includes:

[0020] According to the yarn material deformation degree, the preset number of neighborhood parameters is adjusted to obtain the target number of neighborhood parameters; the target number of neighborhood parameters is positively correlated with the preset number of neighborhood parameters; the target number of neighborhood parameters is negatively correlated with the yarn material deformation degree;

[0021] In the length variable sequence, any length variable is used as the target parameter to construct the neighborhood reference range of the target parameter, wherein the neighborhood reference range is the minimum circumscribed rectangle of the length variables centered on the target parameter and including the number of the target neighborhood parameters.

[0022] Furthermore, the method for obtaining the deformation amplitude includes:

[0023] In the neighborhood reference range of the length variable, the absolute values ​​of the difference values ​​of all length variables are calculated and averaged to obtain the local amplitude;

[0024] All local amplitude variations in the untwisting process are counted in sequence to obtain the local amplitude variation sequence of the untwisting process; all local amplitude variations in the twisting process are counted in sequence to obtain the local amplitude variation sequence corresponding to the twisting process; an inversion operation is performed on the local amplitude variation sequence corresponding to the twisting process to obtain the inverted sequence corresponding to the twisting process; the mean sequence of the inverted sequence corresponding to the twisting process and the local amplitude variation sequence of the untwisting process is calculated to obtain the deformation amplitude variation sequence of the test sample.

[0025] Furthermore, the method for obtaining the corrected pre-tension value includes:

[0026] Clustering all deformation amplitudes of all test samples of the test yarn to obtain two deformation amplitude clustering clusters;

[0027] The maximum cluster center value corresponds to the deformation amplitude cluster cluster as the fine segment cluster cluster; the minimum cluster center value corresponds to the deformation amplitude cluster cluster as the coarse segment cluster;

[0028] The ratio of the number of corresponding elements of the coarse segment cluster and the thin segment cluster is calculated to obtain the coarse-thin segment ratio coefficient; the product of the coarse-thin segment ratio coefficient and a preset adjustment parameter is calculated to obtain a target adjustment value; the product of the target adjustment value and the pre-tension value is calculated to obtain a corrected pre-tension value of the test yarn.

[0029] Furthermore, the method for obtaining the deformation amplitude clustering clusters includes:

[0030] The k-means clustering algorithm is used to cluster all deformation amplitudes of all test samples of the test yarn to obtain two deformation amplitude clustering clusters.

[0031] A yarn twist measurement system, comprising:

[0032] A data acquisition module, used to acquire a yarn length data set for measuring the twist of a test yarn using a pre-tension value; the yarn length data set includes a sequence of yarn length values ​​corresponding to the untwisting process and the twisting process of each test sample;

[0033] A deformation amplitude analysis module is used to obtain the length variable sequence corresponding to the untwisting process and the twisting process of the test sample according to the change characteristics of the yarn length value during the untwisting process and the twisting process of the test sample; obtain the sample deformation degree of the test sample according to the overall distribution of the length variables during the untwisting process and the twisting process of the test sample; obtain the yarn material deformation degree of the test yarn by integrating the sample deformation degrees of all the test samples of the test yarn; determine the neighborhood reference range of each length variable according to the yarn material deformation degree; obtain all deformation amplitudes of the test sample according to the value changes in the neighborhood reference range of the length variable during the untwisting process and the twisting process of the test sample;

[0034] The pre-tension value correction module is used to correct the pre-tension value according to all the deformation amplitudes of all the test samples of the test yarn to obtain the corrected pre-tension value of the test yarn.

[0035] A device for measuring yarn twist comprises a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the method for measuring yarn twist are implemented.

[0036] The present invention has the following beneficial effects:

[0037] During the untwisting and twisting process of the test sample, the yarn length value will change with the change of twist. In order to quantify this change, the length variable sequence of the untwisting process and the twisting process is obtained based on the difference in the yarn length values ​​between adjacent time points. The sample deformation is obtained by analyzing the overall distribution of the length variables of the test sample during the untwisting and twisting process. The sample deformation reflects the deformation ability of the yarn when it is stressed. The yarn material deformation refers to the comprehensive result of the sample deformation of all test samples of the same test yarn, reflecting the overall deformation ability of the yarn material. The neighborhood reference range is determined according to the yarn material deformation, and the neighborhood reference range refers to the window size used to analyze the degree of change of the yarn length variable. The deformation ability of the yarn in the local range is determined by analyzing the numerical changes in the neighborhood reference range of the length variables of the untwisting process and the twisting process of the test sample. The pre-tension value is optimized according to the deformation characteristics of the test yarn, so that the corrected pre-tension value can better adapt to the uneven distribution of the thickness of the test yarn and improve the accuracy of the yarn twist test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 A flow chart of a method for measuring yarn twist provided by one embodiment of the present invention;

[0040] Figure 2 A structural diagram of a yarn twist measurement system provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0041] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of a yarn twist measurement method, measurement system and device proposed by the present invention, its specific implementation, structure, characteristics and effects in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0042] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0043] The following is a detailed description of a yarn twist measurement method, measurement system and device provided by the present invention in conjunction with the accompanying drawings.

[0044] The present invention provides a method, system and device for measuring yarn twist. Figure 1 , which shows a flow chart of a method for measuring yarn twist provided by an embodiment of the present invention, the method comprising the following steps:

[0045] Step S1: obtaining a yarn length data set of twist measurement of a test yarn using a pre-tension value; the yarn length data set includes a sequence of yarn length values ​​corresponding to the untwisting process and the twisting process of each test sample.

[0046] In order to reasonably adjust the pre-tension value of the test yarn, firstly, a set of yarn length data for measuring the twist of the test yarn using the pre-tension value is obtained from the detection database. The specific acquisition process includes:

[0047] For the test yarn that needs to measure the yarn twist, in order to ensure the comprehensiveness and representativeness of the data, different parts of the test yarn are reasonably selected as test samples, and the length of all test samples must be consistent. For each test sample, the untwisting and twisting method is used for measurement. The specific process includes: on the twist tester, a preset pre-tension value is applied through a tension device. One end of the test sample is fixed on a chuck of the tester, and the other end is introduced into another chuck. Rotate the chuck in the untwisting direction, and record the number of rotations of the chuck and the yarn length value of the test sample at each sampling time. When the twist in the test sample is completely removed and the fibers are in a parallel state, stop recording the untwisting data. Then, rotate the chuck in the twisting direction, and also record the number of rotations of the chuck and the yarn length value of the test sample at each sampling time until the test sample reaches the required twisting state. During the untwisting and twisting process, sampling is performed at a preset frequency to obtain the yarn length value of the test sample at each sampling moment, that is, the yarn length value corresponding to each sampling moment in the untwisting process and the yarn length value corresponding to each sampling moment in the twisting process are obtained; according to the order of sampling moments, the yarn length values ​​corresponding to each sampling moment in the untwisting process are counted in sequence to obtain the yarn length value sequence of the test sample in the untwisting process; according to the order of sampling moments, the yarn length values ​​corresponding to each sampling moment in the twisting process are counted in sequence to obtain the yarn length value sequence of the test sample in the twisting process.

[0048] It should be noted that, in one embodiment of the present invention, sampling is performed according to a preset frequency, and each sampling is taken as a sampling moment, and the preset frequency is 1 time / second. It should be noted that, in order to facilitate calculation, all index data involved in the calculation in the embodiment of the present invention are subjected to data preprocessing, thereby eliminating the dimension effect. The specific means of removing the dimension effect are technical means well known to those skilled in the art, and are not limited here. It should be noted that when performing the untwisting and twisting method test, the consistency of the test conditions should be ensured, including the pre-tension value, the speed of untwisting and twisting, etc., to avoid the deviation of the test results. In the present invention, the number of yarn length values ​​recorded by the test sample during the untwisting and twisting process is the same. In one embodiment of the present invention, the pre-tension value is set to 0.5, and the pre-tension value is determined based on the empirical value. Due to the uneven distribution of fiber thickness of the test yarn in actual production, the thickness of the test yarn is different, and the pre-tension value of the test yarn needs to be reasonably adjusted to improve the accuracy of the yarn twist measurement of the test yarn.

[0049] Step S2: according to the variation characteristics of the yarn length values ​​during the untwisting process and the twisting process of the test sample, obtain the length variable sequence corresponding to the untwisting process and the twisting process of the test sample; according to the overall distribution of the length variables during the untwisting process and the twisting process of the test sample, obtain the sample deformation of the test sample; comprehensively test the sample deformation degrees of all test samples of the yarn to obtain the yarn material deformation degree of the test yarn; according to the yarn material deformation degree, determine the neighborhood reference range of each length variable; according to the value changes in the neighborhood reference range of the length variables during the untwisting process and the twisting process of the test sample, obtain all deformation amplitudes of the test sample.

[0050] During the untwisting and twisting process of the test sample, the yarn length value will change with the change of twist. In order to quantify this change, the length variable sequence of the untwisting process and the twisting process is obtained based on the difference in the yarn length values ​​between adjacent time points. The sample deformation is obtained by analyzing the overall distribution of the length variables of the test sample during the untwisting and twisting process. The sample deformation reflects the deformation ability of the yarn when it is subjected to force. The yarn material deformation refers to the comprehensive result of the sample deformation of all test samples of the same test yarn, reflecting the overall deformation ability of the yarn material. The neighborhood reference range is determined based on the yarn material deformation. The neighborhood reference range refers to the window size used to analyze the degree of change of the yarn length variable. The deformation ability of the yarn in the local range is determined by analyzing the numerical changes in the neighborhood reference range of the length variables of the untwisting and twisting processes of the test sample.

[0051] In order to quantify the change of yarn length in the untwisting process and the twisting process, preferably, in one embodiment of the present invention, the method for obtaining the length variable sequence includes:

[0052] For the yarn length value sequence of the test sample in the untwisting process, the difference between each yarn length value and its previous yarn length value is calculated to obtain the length variable corresponding to each yarn length value of the test sample in the untwisting process; the length variable corresponding to each yarn length value in the untwisting process is counted in sequence to obtain the length variable sequence corresponding to the untwisting process;

[0053] For the yarn length value sequence of the twisting process of the test sample, the difference between each yarn length value and the subsequent yarn length value is calculated to obtain the length variable corresponding to each yarn length value of the test sample in the twisting process; the length variables corresponding to each yarn length value in the twisting process are counted in turn to obtain the length variable sequence corresponding to the twisting process.

[0054] For the above steps, it is considered that during the untwisting process, the yarn gradually becomes longer due to the release of twist. For the yarn length value sequence of the untwisting process of the sample to be analyzed, the difference between each yarn length value and its previous yarn length value is calculated to obtain the length variable corresponding to each yarn length value of the sample to be analyzed during the untwisting process. The length variable reflects the increase in the length of the yarn during the untwisting process; the length variables at each sampling moment in the untwisting process are counted in sequence, and these length variables are arranged in chronological order to form a length variable sequence corresponding to the untwisting process. During the twisting process, due to the increase in twist, the yarn becomes tighter and its yarn length value decreases. By calculating the difference between each yarn length and the yarn length at the next sampling moment, the length variable corresponding to each yarn length value of the test sample during the twisting process is obtained. The length variable reflects the decrease in the length of the yarn during the twisting process; the length variables at each sampling moment in the twisting process are counted in sequence, and these length variables are arranged in chronological order to form a length variable sequence corresponding to the twisting process.

[0055] In order to reasonably adjust the pre-tension value of the test yarn, it is necessary to analyze the thickness distribution of the test yarn. In order to accurately analyze the thickness distribution of the test yarn, it is necessary to determine a suitable neighborhood reference range for the analysis length variable. This range determines the number and range of length variable data considered when analyzing the yarn thickness. Selecting a suitable neighborhood reference range is crucial for accurately evaluating the thickness distribution of the yarn. Since the yarn material is a key factor affecting the selection of the neighborhood reference range, yarns of different materials have different degrees of deformation when twist is measured. For yarns of different materials, it is necessary to select a suitable neighborhood reference range based on the characteristics of their deformation degree.

[0056] In order to analyze the deformation characteristics of the yarn material used in the test yarn, the sample deformation degree can be obtained by first analyzing the overall distribution of the length variable of the test sample during the untwisting and twisting process. The sample deformation degree reflects the deformation characteristics of the test sample when subjected to force. Preferably, in one embodiment of the present invention, the method for obtaining the sample deformation degree includes:

[0057] Calculate the mean of all length variables of the test sample during the untwisting process to obtain the overall deformation measurement of the untwisting process;

[0058] Calculate the mean of all length variables of the test sample during the twisting process to obtain the overall deformation measurement of the twisting process;

[0059] The average of the overall deformation measure of the untwisting process and the overall deformation measure of the twisting process is calculated to obtain the sample deformation of the test sample.

[0060] According to the above steps, the mean of all length variables in the untwisting process is calculated. This mean represents the average change in length of the test sample in the untwisting process, that is, the overall deformation measurement of the untwisting process. Similarly, the mean of all length variables in the twisting process is recorded and calculated. This mean represents the average change in length of the test sample in the twisting process, that is, the overall deformation measurement of the twisting process. The mean of these two overall deformation measurements is calculated to obtain the sample deformation degree of the test sample. The sample deformation degree comprehensively reflects the deformation characteristics of the test sample in both untwisting and twisting states, and provides an important basis for evaluating the deformation performance of the test sample material.

[0061] In order to analyze the deformation characteristics of the yarn material used for the test yarn, preferably, in one embodiment of the present invention, the method for obtaining the deformation degree of the yarn material includes:

[0062] Take any test sample as the sample to be analyzed, calculate the variance of all length variables of the sample to be analyzed during the untwisting process, calculate the variance of all length variables of the sample to be analyzed during the twisting process, perform negative correlation mapping on the largest variance, and obtain the reference weight of the sample to be analyzed;

[0063] The sample deformation of all test samples is weighted and averaged by using the reference weights of all test samples of the test yarn to obtain the yarn material deformation of the test yarn. In one embodiment of the present invention, the negative correlation mapping may be in the form of inverse proportion or negative exponential power, which is not limited here.

[0064] For the above steps, it is considered that the deformation degree of yarn material refers to the comprehensive result of the sample deformation degree of all test samples of the same test yarn. It reflects the overall deformation ability of the yarn material when subjected to force and is an important indicator for evaluating the performance of the yarn material. Since the test samples are made from the same production batch, using the same raw materials and production process, the deformation characteristics of the test samples are representative to a certain extent and can reflect the overall deformation ability of the test yarn. For any test sample, the variance of all length variables in the untwisting process and the twisting process is calculated respectively. The variance reflects the degree of discreteness of the length variable, that is, the instability of the deformation. The larger the variance, the more drastic the change of the length variable, and the greater the influence of the external environment or human interference. In order to convert the variance into a reference weight that can be used for weighting, the largest variance is negatively correlated. Negative correlation mapping means that the larger the variance, the smaller the reference weight, because a larger variance means greater instability or interference in the data. The weighted average value can take into account the differences in deformation characteristics of different test samples, so that the test samples with more stable deformation have a greater impact on the final result. Finally, the deformation degree of the yarn material of the test yarn is obtained, which comprehensively reflects the deformation characteristics of all test samples and represents the deformation characteristics of the yarn material used in the test yarn.

[0065] In order to accurately evaluate the degree of change of the length variable, it is considered that the smaller the deformation degree of the yarn material, the smaller the length change of the yarn in a short time, or even no obvious change. On the contrary, the greater the deformation degree of the yarn material, the greater the length change in a short time. When calculating the deformation amplitude of the yarn, the choice of window size is crucial. For yarns with a small deformation degree of yarn material, since their length changes slowly, a larger window needs to be set to capture their length changes. For yarns with a large deformation degree of yarn material, since their length changes quickly, a smaller window can capture significant changes, so a smaller window should be set. It is necessary to select a suitable neighborhood reference range based on the deformation degree of the yarn material of the test yarn. Preferably, in one embodiment of the present invention, the method for obtaining the neighborhood reference range includes:

[0066] According to the yarn material deformation degree, the preset number of neighborhood parameters is adjusted to obtain the target number of neighborhood parameters; the target number of neighborhood parameters is positively correlated with the preset number of neighborhood parameters; the target number of neighborhood parameters is negatively correlated with the yarn material deformation degree. In one implementation of the present invention, the formula for obtaining the target number of neighborhood parameters includes:

[0067] ;in, is the number of target neighborhood parameters; is the number of preset neighborhood parameters; is the deformation degree of yarn material; is the rounding symbol; is an exponential function with e as the base. In one embodiment of the present invention, the number of preset neighborhood parameters is 7, which can be set by the implementer according to the implementation scenario.

[0068] In the formula, 1 represents the reference value, and the number of preset neighborhood parameters is adjusted by using the yarn material deformation degree to obtain the number of target neighborhood parameters. By reasonably setting the number of target neighborhood parameters, the degree of change of the length variable can be accurately evaluated later.

[0069] In the length variable sequence, any length variable is taken as the target parameter to construct the neighborhood reference range of the target parameter. The neighborhood reference range is the minimum enclosing rectangle of the length variables centered on the target parameter and including the number of target neighborhood parameters.

[0070] Consider that the thickness of the yarn is closely related to its degree of deformation when subjected to force. Thin yarns are more likely to deform when subjected to tension because they have fewer internal fibers and a relatively loose structure; while thick yarns have more internal fibers and a tighter structure, which can better resist stretching and have a relatively smaller degree of deformation. This difference in deformation degree, i.e., deformation amplitude, can be used to distinguish between thick and thin segments of the yarn. After determining the neighborhood reference range, the deformation amplitude of the test sample during the untwisting and twisting process can be analyzed. The deformation amplitude reflects the deformation ability of the yarn in a local range. Preferably, in one embodiment of the present invention, the method for obtaining the deformation amplitude includes:

[0071] In the neighborhood reference range of the length variable, the absolute values ​​of the difference values ​​of all length variables are calculated and averaged to obtain the local amplitude;

[0072] All local amplitude variations in the untwisting process are counted in sequence to obtain the local amplitude variation sequence of the untwisting process; all local amplitude variations in the twisting process are counted in sequence to obtain the local amplitude variation sequence corresponding to the twisting process; the local amplitude variation sequence corresponding to the twisting process is inverted to obtain the inverted sequence corresponding to the twisting process; the mean sequence of the inverted sequence corresponding to the twisting process and the local amplitude variation sequence of the untwisting process is calculated to obtain the deformation amplitude variation sequence of the test sample.

[0073] For the above steps, first, for each length variable, within its neighborhood reference range, the absolute value of the difference between the length variable and other length variables in its neighborhood is calculated, and the absolute values ​​of these difference values ​​are averaged to obtain the local amplitude of the length variable. This local amplitude reflects the change amplitude of the length variable within the neighborhood. During the untwisting process, the local amplitude of each time point is recorded in sequence to form a local amplitude sequence of the untwisting process. Similarly, during the twisting process, the local amplitude of each time point is also recorded in sequence to form a local amplitude sequence of the twisting process. The local amplitude sequence of the twisting process is inverted, that is, the first element in the sequence becomes the last, the second element becomes the second to last, and so on, to obtain the inverted sequence corresponding to the twisting process. The purpose of this step is to simulate or compare the symmetry of the change of the length variable during twisting and untwisting. The inverted local amplitude sequence of the twisting process and the local amplitude sequence of the untwisting process are averaged for the corresponding elements, that is, the two local amplitude values ​​at each time point are added and divided by 2 to obtain the deformation amplitude at that time point. The deformation amplitudes at all time points are calculated sequentially to form a deformation amplitude sequence of the test sample. This deformation amplitude sequence reflects the average change amplitude of the length variable during the entire untwisting and twisting process, which can be used to analyze the deformation characteristics or mechanical properties of the material.

[0074] Step S3: correcting the pre-tension value according to all deformation amplitudes of all test samples of the test yarn to obtain the corrected pre-tension value of the test yarn.

[0075] The pre-tension value is optimized according to the deformation characteristics of the test yarn, so that the corrected pre-tension value can better adapt to the uneven thickness distribution of the test yarn and improve the accuracy of the yarn twist test result.

[0076] Considering that thick yarn can withstand higher pre-tension due to its large number of fibers and close interweaving, thin yarn is more likely to reach its endurance limit when stretched due to its small number of fibers and weak interaction. Therefore, when dealing with yarns of inconsistent thickness, we need to reasonably adjust the pre-tension value according to the thickness ratio of the yarn. Preferably, in one embodiment of the present invention, the method for obtaining the corrected pre-tension value includes:

[0077] Clustering all deformation amplitudes of all test samples of the test yarn to obtain two deformation amplitude clustering clusters;

[0078] The cluster with the largest cluster center value corresponding to the deformation amplitude is regarded as the fine segment cluster; the cluster with the smallest cluster center value corresponding to the deformation amplitude is regarded as the coarse segment cluster;

[0079] Calculate the ratio of the number of elements corresponding to the coarse segment cluster and the thin segment cluster to obtain the coarse-thin segment ratio coefficient; calculate the product of the coarse-thin segment ratio coefficient and the preset adjustment parameter to obtain the target adjustment value; calculate the product of the target adjustment value and the pre-tension value to obtain the corrected pre-tension value of the test yarn. In one embodiment of the present invention, the method for obtaining the clustering clusters includes: using the k-means clustering algorithm to cluster all deformation amplitudes of all test samples of the test yarn to obtain two deformation amplitude clustering clusters. It should be noted that the k-means clustering algorithm is a technical means well known to those skilled in the art and will not be described in detail here. In one embodiment of the present invention, the preset adjustment parameter is 1.32, which can be set by the implementer according to the implementation scenario.

[0080] Specifically, cluster analysis is performed on all deformation amplitudes of all test samples of the test yarn. Clustering is a commonly used data analysis method that can divide data into several groups or clusters so that the data points in the same cluster are similar to each other, while the data points between different clusters are quite different. In this step, the k-means clustering algorithm is used to divide the deformation amplitude into two clusters. The k-means clustering algorithm is a distance-based clustering algorithm that finds the division of k clusters that minimizes the variance within the cluster. In this case, k is set to 2, so two clusters are obtained. After obtaining the two clusters, their cluster center values ​​are compared to determine which is the thin segment cluster and which is the thick segment cluster. The cluster with a larger cluster center value is considered to be a thin segment cluster because it represents the thinner or more deformable part of the yarn; while the cluster with a smaller cluster center value is considered to be a thick segment cluster because it represents the thicker or less deformable part of the yarn. The ratio of the number of elements in the thick segment cluster and the thin segment cluster is calculated. This ratio is called the coarse-thin segment ratio coefficient, which reflects the relative number or ratio of coarse and thin segments in the yarn. Set a preset adjustment parameter, which is used to adjust the pre-tension value according to the coarse-thin segment ratio coefficient. Calculate the product of the coarse-thin segment ratio coefficient and the preset adjustment parameter to obtain the target adjustment value. If the coarse segment ratio is high, the target adjustment value will increase accordingly; conversely, if the thin segment ratio is high, the target adjustment value will decrease. Calculate the product of the target adjustment value and the original pre-tension value to obtain the corrected pre-tension value. The corrected pre-tension value takes into account the thickness inconsistency of the yarn and is more in line with the actual tensile properties of the tested yarn.

[0081] The corrected pre-tension value can better adapt to the uneven distribution of the thickness of the test yarn and improve the accuracy of the yarn twist test results. Furthermore, based on the corrected pre-tension value of the test yarn, the twist value of the test yarn is obtained by using the untwisting and twisting method. It should be noted that the untwisting and twisting method is a prior art well known to those skilled in the art. The untwisting and twisting method is a method for indirectly measuring the twist of the yarn. It untwistes and reversely twists the test yarn under the corrected pre-tension value, and observes the number of twists required for the yarn to return to the starting length, thereby calculating the twist of the test yarn, which will not be elaborated here.

[0082] In summary, the embodiments of the present invention provide a method, system and device for measuring yarn twist. The present invention first obtains the length variable sequence corresponding to the untwisting process and twisting process of the test sample according to the change characteristics of the yarn length value in the untwisting process and twisting process of the test sample; obtains all deformation amplitudes of the test sample according to the value changes in the neighborhood reference range of the length variables in the untwisting process and twisting process of the test sample; and corrects the pre-tension value according to all deformation amplitudes of all test samples of the test yarn to obtain the corrected pre-tension value of the test yarn. The present invention conducts an in-depth analysis of the uneven distribution of the thickness of the test yarn, reasonably sets the corrected pre-tension value, and improves the accuracy of the yarn twist test results.

[0083] The present invention also proposes a yarn twist measurement system, see Figure 2 , which shows a structure diagram of a yarn twist measurement system provided by an embodiment of the present invention, the system includes: a data acquisition module 101, a deformation amplitude analysis module 102 and a pre-tension value correction module 103.

[0084] A data acquisition module is used to acquire a yarn length data set for measuring the twist of the test yarn using a pre-tension value; the yarn length data set includes a sequence of yarn length values ​​corresponding to the untwisting process and the twisting process of each test sample;

[0085] The deformation amplitude analysis module is used to obtain the length variable sequence corresponding to the untwisting process and the twisting process of the test sample according to the change characteristics of the yarn length value during the untwisting process and the twisting process of the test sample; obtain the sample deformation degree of the test sample according to the overall distribution of the length variable during the untwisting process and the twisting process of the test sample; comprehensively test the sample deformation degrees of all test samples of the yarn to obtain the yarn material deformation degree of the test yarn; determine the neighborhood reference range of each length variable according to the yarn material deformation degree; obtain all deformation amplitudes of the test sample according to the value changes in the neighborhood reference range of the length variable during the untwisting process and the twisting process of the test sample;

[0086] The pre-tension value correction module is used to correct the pre-tension value according to all deformation amplitudes of all test samples of the test yarn, and obtain the corrected pre-tension value of the test yarn.

[0087] It should be noted that: the system provided in the above embodiment is only illustrated by the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the computer device is divided into different functional modules to complete all or part of the functions described above. In addition, the yarn twist measurement system and the yarn twist measurement method embodiment provided in the above embodiment belong to the same concept. The specific implementation process is detailed in the method embodiment and will not be repeated here.

[0088] A yarn twist measuring device comprises a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the yarn twist measuring method as described above are implemented.

[0089] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0090] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A method for measuring yarn twist, characterized in that: The method comprises: Acquire a yarn length data set for measuring twist of a test yarn using a pre-tension value; the yarn length data set includes a sequence of yarn length values ​​corresponding to the untwisting process and the twisting process of each test sample; According to the variation characteristics of the yarn length values ​​during the untwisting process and the twisting process of the test sample, the length variable sequence corresponding to the untwisting process and the twisting process of the test sample is obtained; according to the overall distribution of the length variables during the untwisting process and the twisting process of the test sample, the sample deformation degree of the test sample is obtained; the yarn material deformation degree of the test yarn is obtained by integrating the sample deformation degrees of all the test samples of the test yarn; according to the yarn material deformation degree, the neighborhood reference range of each length variable is determined; according to the value changes in the neighborhood reference range of the length variables during the untwisting process and the twisting process of the test sample, all deformation amplitudes of the test sample are obtained; According to all the deformation amplitudes of all the test samples of the test yarn, the pre-tension value is corrected to obtain a corrected pre-tension value of the test yarn; The method for obtaining the corrected pretension value includes: Clustering all deformation amplitudes of all test samples of the test yarn to obtain two deformation amplitude clustering clusters; The maximum cluster center value corresponds to the deformation amplitude cluster cluster as the fine segment cluster cluster; the minimum cluster center value corresponds to the deformation amplitude cluster cluster as the coarse segment cluster; The ratio of the number of corresponding elements of the coarse segment cluster and the thin segment cluster is calculated to obtain the coarse-thin segment ratio coefficient; the product of the coarse-thin segment ratio coefficient and a preset adjustment parameter is calculated to obtain a target adjustment value; the product of the target adjustment value and the pre-tension value is calculated to obtain a corrected pre-tension value of the test yarn.

2. A method for measuring yarn twist according to claim 1, characterized in that: The method for obtaining the length variable sequence includes: For the yarn length value sequence of the test sample in the untwisting process, the difference between each yarn length value and the previous yarn length value is calculated to obtain the length variable corresponding to each yarn length value of the test sample in the untwisting process; the length variable corresponding to each yarn length value in the untwisting process is counted in sequence to obtain the length variable sequence corresponding to the untwisting process; For the yarn length value sequence of the twisting process of the test sample, the difference between each yarn length value and the subsequent yarn length value is calculated to obtain the length variable corresponding to each yarn length value of the test sample in the twisting process; the length variables corresponding to each yarn length value in the twisting process are counted in turn to obtain the length variable sequence corresponding to the twisting process.

3. The method for measuring yarn twist according to claim 1, characterized in that: The method for obtaining the sample deformation degree includes: Calculating the mean of all length variables of the test sample during the untwisting process to obtain an overall deformation measurement of the untwisting process; Calculating the mean of all length variables of the test sample during the twisting process to obtain an overall deformation measurement of the twisting process; The average of the overall deformation measure of the untwisting process and the overall deformation measure of the twisting process is calculated to obtain the sample deformation of the test sample.

4. The method for measuring yarn twist according to claim 1, characterized in that: The method for obtaining the yarn material deformation degree comprises: Taking any one of the test samples as a sample to be analyzed, calculating the variance of all the length variables of the sample to be analyzed during the untwisting process, calculating the variance of all the length variables of the sample to be analyzed during the twisting process, performing negative correlation mapping on the largest variance, and obtaining a reference weight of the sample to be analyzed; The reference weights of all the test samples of the test yarn are used to perform weighted average calculation on the sample deformation degrees of all the test samples to obtain the yarn material deformation degree of the test yarn.

5. The method for measuring yarn twist according to claim 1, characterized in that: The method for obtaining the neighborhood reference range includes: According to the yarn material deformation degree, the preset number of neighborhood parameters is adjusted to obtain the target number of neighborhood parameters; the target number of neighborhood parameters is positively correlated with the preset number of neighborhood parameters; the target number of neighborhood parameters is negatively correlated with the yarn material deformation degree; In the length variable sequence, any length variable is used as the target parameter to construct the neighborhood reference range of the target parameter, wherein the neighborhood reference range is the minimum circumscribed rectangle of the length variables centered on the target parameter and including the number of the target neighborhood parameters.

6. A method for measuring yarn twist according to claim 1, characterized in that: Methods for obtaining deformation amplitude include: In the neighborhood reference range of the length variable, the absolute values ​​of the difference values ​​of all length variables are calculated and averaged to obtain the local amplitude; All local amplitude variations in the untwisting process are counted in sequence to obtain the local amplitude variation sequence of the untwisting process; all local amplitude variations in the twisting process are counted in sequence to obtain the local amplitude variation sequence corresponding to the twisting process; an inversion operation is performed on the local amplitude variation sequence corresponding to the twisting process to obtain the inverted sequence corresponding to the twisting process; the mean sequence of the inverted sequence corresponding to the twisting process and the local amplitude variation sequence of the untwisting process is calculated to obtain the deformation amplitude variation sequence of the test sample.

7. A method for measuring yarn twist according to claim 1, characterized in that: The method for obtaining the deformation amplitude clustering clusters includes: The k-means clustering algorithm is used to cluster all deformation amplitudes of all test samples of the test yarn to obtain two deformation amplitude clustering clusters.

8. A yarn twist measurement system, characterized in that: include: A data acquisition module, used to acquire a yarn length data set for measuring the twist of a test yarn using a pre-tension value; the yarn length data set includes a sequence of yarn length values ​​corresponding to the untwisting process and the twisting process of each test sample; The deformation amplitude analysis module is used to obtain the length variable sequence corresponding to the untwisting process and the twisting process of the test sample according to the change characteristics of the yarn length value during the untwisting process and the twisting process of the test sample; obtain the sample deformation degree of the test sample according to the overall distribution of the length variables during the untwisting process and the twisting process of the test sample; and obtain the yarn material deformation degree of the test yarn by integrating the sample deformation degrees of all the test samples of the test yarn; Determine the neighborhood reference range of each length variable according to the yarn material deformation degree; obtain all deformation amplitudes of the test sample according to the value changes in the neighborhood reference range of the length variable during the untwisting process and the twisting process of the test sample; A pre-tension value correction module, used for correcting the pre-tension value according to all the deformation amplitudes of all the test samples of the test yarn, to obtain a corrected pre-tension value of the test yarn; The method for obtaining the corrected pretension value includes: Clustering all deformation amplitudes of all test samples of the test yarn to obtain two deformation amplitude clustering clusters; The maximum cluster center value corresponds to the deformation amplitude cluster cluster as the fine segment cluster cluster; the minimum cluster center value corresponds to the deformation amplitude cluster cluster as the coarse segment cluster; The ratio of the number of corresponding elements of the coarse segment cluster and the thin segment cluster is calculated to obtain the coarse-thin segment ratio coefficient; the product of the coarse-thin segment ratio coefficient and a preset adjustment parameter is calculated to obtain a target adjustment value; the product of the target adjustment value and the pre-tension value is calculated to obtain a corrected pre-tension value of the test yarn.

9. A device for measuring yarn twist, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method for measuring yarn twist as claimed in any one of claims 1 to 7 are implemented.

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