A method and system for adaptive adjustment of weaving tension

Abstract

The present application relates to program control system technical field, specifically to a kind of weaving tension self-adaptive adjustment method and system, comprising the following steps: obtaining the current fabric weave file and warp yarn parameter of loom, the fabric weave file is parsed to generate fabric weave binary matrix, while according to the target tension value set by the warp yarn parameter.This application, according to the change rate of theoretical warp yarn consumption length, calculates dynamic feedforward compensation linear velocity, and directly corrects the feedback adjustment speed with this compensation value, can adjust the warp motor speed in advance before the tension fluctuation caused by the mutation of fabric weave structure, through the double control strategy of feedforward prediction and feedback correction, eliminate the hysteresis caused by pure feedback control, ensure that warp tension is maintained in constant range during high-speed operation and complex texture weaving process of loom, improve fabric surface flatness.

Description

Technical Field

[0001] This invention relates to the field of program control system technology, and in particular to a method and system for adaptive adjustment of weaving tension. Background Technology

[0002] Existing weaving tension regulation technologies mostly employ passive control modes based on instantaneous tension feedback, relying on mechanical backbeam oscillation or single sensor feedback signals to drive the warp feed action. In actual high-speed weaving processes, the control system often only activates the regulation mechanism after tension fluctuations actually occur and are captured by the sensor. This lag means the warp feed motor response is always slower than the tension change cycle. When faced with complex and variable fabric structures, such as a sudden change from plain weave to satin weave, the warp yarn consumption fluctuates dramatically and instantaneously. Traditional fixed-parameter PID controllers struggle to adapt to this nonlinear time-varying characteristic, failing to quickly bring the tension back to the set value and prone to overshoot or oscillation. Therefore, improvements are needed. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the existing technology and to propose a weaving tension adaptive adjustment method and system.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a weaving tension adaptive adjustment method, comprising the following steps:

[0005] Obtain the current fabric structure file and warp parameters of the loom, parse the fabric structure file to generate a fabric structure binary matrix, and set the target tension value according to the warp parameters;

[0006] Analyze the warp yarn interlacing state corresponding to the current weft yarn in the fabric structure binary matrix, and calculate the theoretical warp yarn consumption length in the current weft yarn weaving process based on the warp yarn interlacing state and the warp yarn parameters;

[0007] The actual tension value of the warp yarn is collected in real time using a tension sensor. The tension deviation between the actual tension value of the warp yarn and the target tension value is calculated. The tension deviation is input into a variable domain fuzzy PID controller for calculation to obtain the feedback adjustment linear velocity.

[0008] The dynamic feedforward compensation linear speed of the warp feed motor is calculated based on the rate of change of the theoretical warp yarn consumption length. The feedback adjustment linear speed is then corrected using the dynamic feedforward compensation linear speed to generate the final warp feed linear speed command.

[0009] The operation of the warp feed motor is controlled according to the final warp feed speed command to achieve adaptive adjustment of weaving tension.

[0010] Preferably, the steps of obtaining the current fabric structure file and warp parameters of the loom, parsing the fabric structure file to generate a fabric structure binary matrix, and setting the target tension value according to the warp parameters are as follows:

[0011] The fabric structure file stored in the loom control system is read, and the pattern data in the fabric structure file is identified.

[0012] The pattern data is discretized according to the interlacing points of the warp and weft yarns to construct the binary matrix of the fabric structure;

[0013] In the fabric structure binary matrix, the interlacing point where the warp yarns are above the weft yarns is marked with a value of 1, and the interlacing point where the warp yarns are below the weft yarns is marked with a value of 0.

[0014] The warp parameters are entered through a human-computer interaction interface. The warp parameters include warp diameter, warp elastic modulus, and warp beam radius.

[0015] Based on the elastic modulus of the warp yarns and the weaving process requirements, the target tension value is set during the weaving process.

[0016] Preferably, the step of analyzing the warp interlacing state corresponding to the current weft yarn in the fabric structure binary matrix, and calculating the theoretical warp yarn consumption length in the current weft yarn weaving process based on the warp interlacing state and the warp parameters, specifically includes:

[0017] Extract the row of data corresponding to the current weft yarn in the binary matrix of the fabric structure as the current weft yarn row vector;

[0018] Traverse the current weft yarn row vector, count the number of times the value in the current weft yarn row vector jumps, and define the number of times as the number of interlacing points;

[0019] The weaving resistance compensation index is calculated based on the number of interlacing points and the warp parameters, and the theoretical warp consumption length is calculated using the weaving resistance compensation index.

[0020] The formula for calculating the weaving resistance compensation index is as follows:

[0021] ;

[0022] in, This represents the weaving resistance compensation index. Indicates the number of interlacing points. This represents the total number of columns in the binary matrix of the fabric structure. The diameter of the warp yarn is expressed in millimeters. This represents the preset first interleaving weight coefficient. This represents the preset second diameter weighting coefficient;

[0023] Based on the weaving resistance compensation index and combined with geometric trigonometric function relationships, the increased length due to the bending of the warp yarn at the interlacing point is calculated. The increased length is then added to the basic width of the fabric to obtain the theoretical warp yarn consumption length.

[0024] Preferably, the steps of using a tension sensor to collect the actual warp tension value in real time, calculating the tension deviation between the actual warp tension value and the target tension value, and inputting the tension deviation into a variable universe fuzzy PID controller for calculation to obtain feedback adjustment of the linear velocity are as follows:

[0025] The actual tension value of the warp yarn is collected by the tension sensor installed at the rear beam of the loom.

[0026] The tension deviation is obtained by subtracting the target tension value from the actual warp tension value, and the rate of change of the tension deviation over time is calculated.

[0027] The tension deviation and the rate of change are used as input variables for the variable universe fuzzy PID controller;

[0028] The domain range of the input variables is adjusted in real time using a scaling factor function;

[0029] When the absolute value of the tension deviation is less than the preset fine-tuning threshold, the domain range is compressed using the scaling factor function;

[0030] When the absolute value of the tension deviation is greater than the fine-tuning threshold, the domain range is expanded using the scaling factor function;

[0031] Fuzzy inference is performed based on the adjusted universe of discourse to calculate the correction amount of the PID parameters, and the feedback regulation linear velocity is calculated using the corrected PID parameters.

[0032] Preferably, the step of performing fuzzy inference based on the adjusted universe of discourse, calculating the correction amount of the PID parameters, and using the corrected PID parameters to calculate the feedback regulation linear velocity specifically includes:

[0033] An asymmetric fuzzy rule table is established in the variable universe fuzzy PID controller;

[0034] Determine the sign and direction of the tension deviation;

[0035] If the tension deviation is positive, it indicates that the actual tension value of the warp yarn is greater than the target tension value. Then, a larger proportional gain parameter is selected according to the asymmetric fuzzy rule table.

[0036] If the tension deviation is negative, it indicates that the actual tension value of the warp yarn is less than the target tension value. Then, a smaller integral gain parameter is selected according to the asymmetric fuzzy rule table.

[0037] The feedback adjustment linear velocity is calculated based on the selected proportional gain parameter and integral gain parameter.

[0038] Preferably, the steps of calculating the dynamic feedforward compensation linear speed of the warp feed motor based on the rate of change of the theoretical warp yarn consumption length, correcting the feedback adjustment linear speed using the dynamic feedforward compensation linear speed, and generating the final warp feed linear speed command are as follows:

[0039] Store the historical theoretical warp yarn consumption length calculated during the weaving of the previous weft yarn;

[0040] Calculate the difference between the theoretical warp yarn consumption length and the historical theoretical warp yarn consumption length to obtain the single weft yarn consumption increment;

[0041] Divide the single-weft yarn consumption increment by the time required for the loom spindle to rotate one revolution to obtain the corresponding linear velocity increment;

[0042] The linear velocity increment is defined as the dynamic feedforward compensation linear velocity;

[0043] The dynamic feedforward compensation linear velocity and the feedback adjustment linear velocity are directly superimposed to obtain the superimposed bus velocity.

[0044] The superimposed bus speed is subjected to amplitude limiting processing, and the speed after amplitude limiting is used as the final warp feed line speed command.

[0045] Preferably, the step of directly superimposing the dynamic feedforward compensation linear velocity and the feedback adjustment linear velocity to obtain the superimposed bus velocity is as follows:

[0046] Monitor the angular position signal of the loom spindle;

[0047] When the angle position signal is detected to be within a preset angle window before the weft insertion action occurs, a speed superposition operation is triggered.

[0048] Within the preset angle window, the dynamic feedforward compensation linear velocity is superimposed on the feedback adjustment linear velocity in the form of pulses;

[0049] By performing the speed superposition operation, the rotational speed of the warp feed motor is changed in advance before the warp tension fluctuates drastically due to the weft insertion action, so as to counteract the tension interference caused by the change in the fabric structure and output the superimposed bus speed.

[0050] Preferably, the warp parameters include the warp beam radius; the step of controlling the operation of the warp feed motor according to the final warp feed speed command to complete the adaptive adjustment of weaving tension specifically includes:

[0051] Using formula The final warp feed linear speed command is converted into the target angular velocity of the warp feed motor, wherein This refers to the final warp feed line speed command. The radius of the weaving beam. The target angular velocity of the feed motor;

[0052] The target angular velocity of the warp feed motor is sent to the warp feed motor via a servo driver;

[0053] The warp feed motor drives the warp beam to rotate according to the target angular velocity of the warp feed motor, thereby releasing or rewinding the warp yarns;

[0054] During the operation of the yarn feeding motor, the actual speed and position feedback of the yarn feeding motor are monitored in real time;

[0055] The inner loop speed control circuit ensures that the actual speed of the yarn-feeding motor strictly follows the target angular velocity of the yarn-feeding motor.

[0056] By changing the amount of warp yarn fed by the operation of the warp feed motor, the actual tension value of the warp yarn is made to approach the target tension value.

[0057] The present invention also provides a system comprising:

[0058] The fabric data parsing module is used to obtain the current fabric structure file and warp parameters of the loom, parse the fabric structure file to generate a fabric structure binary matrix, and set the target tension value according to the warp parameters.

[0059] The warp yarn consumption calculation module is used to analyze the warp yarn interlacing state corresponding to the current weft yarn in the fabric structure binary matrix, and calculate the theoretical warp yarn consumption length in the current weft yarn weaving process based on the warp yarn interlacing state and the warp yarn parameters.

[0060] The tension detection and control module is used to collect the actual tension value of the warp yarn in real time using a tension sensor, calculate the tension deviation between the actual tension value of the warp yarn and the target tension value, and input the tension deviation into a variable domain fuzzy PID controller for calculation to obtain feedback adjustment of the linear velocity.

[0061] The feedforward compensation module is used to calculate the dynamic feedforward compensation linear speed of the warp feed motor based on the rate of change of the theoretical warp consumption length, and to use the dynamic feedforward compensation linear speed to correct the feedback adjustment linear speed, thereby generating the final warp feed linear speed command.

[0062] The execution control module is used to control the operation of the warp feed motor according to the final warp feed speed command, so as to complete the adaptive adjustment of weaving tension.

[0063] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0064] This invention generates a binary matrix by parsing fabric structure files and sets the target tension in conjunction with warp parameters. This transforms complex physical textures into a computer-processable digital mapping, identifying the warp and weft interlacing state during each weft weaving process. Based on the interlacing state and warp physical properties, the theoretical warp yarn consumption length during the current weft weaving process is calculated, establishing a predictive control benchmark based on a mechanistic model, thus changing the passive adjustment mode that relies solely on post-event feedback. Real-time data is collected using tension sensors, and the deviation from the target value is calculated. This deviation is input into a variable-domain fuzzy PID calculation system. The variable-domain mechanism dynamically expands and contracts the domain range according to the deviation magnitude. When the deviation is large, the domain is expanded to improve response speed; when the deviation is small, the domain is compressed to enhance control accuracy. This effectively solves the contradiction between speed and stability that traditional fixed-parameter control struggles to achieve in nonlinear time-varying systems. The dynamic feedforward compensation linear speed is calculated based on the rate of change of theoretical warp yarn consumption length, and this compensation value is directly used to correct the feedback adjustment speed. This allows the warp motor speed to be adjusted in advance before tension fluctuations occur due to abrupt changes in the fabric structure. Through the dual control strategy of feedforward prediction and feedback correction, the lag caused by simple feedback control is eliminated, ensuring that the warp tension is always maintained within a constant range during high-speed operation and complex texture weaving, thereby improving the smoothness of the fabric surface. Attached Figure Description

[0065] Figure 1 This is a schematic diagram of the steps of the present invention. Detailed Implementation

[0066] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0067] Please see Figure 1 This invention provides a technical solution, a method for adaptive adjustment of weaving tension, comprising the following steps:

[0068] Obtain the current fabric structure file and warp parameters of the loom, parse the fabric structure file to generate a fabric structure binary matrix, and set the target tension value according to the warp parameters;

[0069] Analyze the warp yarn interlacing state corresponding to the current weft yarn in the fabric structure binary matrix, and calculate the theoretical warp yarn consumption length in the current weft yarn weaving process based on the warp yarn interlacing state and warp yarn parameters;

[0070] The actual warp tension value is collected in real time using a tension sensor. The tension deviation between the actual warp tension value and the target tension value is calculated. The tension deviation is input into a variable domain fuzzy PID controller for calculation to obtain feedback adjustment of the linear velocity.

[0071] The dynamic feedforward compensation linear speed of the warp feed motor is calculated based on the rate of change of the theoretical warp yarn consumption length. The dynamic feedforward compensation linear speed is used to correct the feedback adjustment linear speed and generate the final warp feed linear speed command.

[0072] The operation of the warp feed motor is controlled according to the final warp feed speed command to achieve adaptive adjustment of weaving tension.

[0073] In this embodiment, the steps of obtaining the current fabric structure file and warp parameters of the loom, parsing the fabric structure file to generate a fabric structure binary matrix, and setting the target tension value according to the warp parameters are as follows: the loom control system reads the stored fabric structure file, identifies the pattern data in the fabric structure file, discretizes the pattern data according to the interlacing points of the warp and weft yarns, constructs the fabric structure binary matrix, marks the interlacing points where the warp yarns are above the weft yarns as value 1, and marks the interlacing points where the warp yarns are below the weft yarns as value 0, and inputs the warp parameters through the human-machine interface. The warp parameters include the warp diameter, warp elastic modulus, and warp beam radius. The target tension value during the weaving process is set according to the warp elastic modulus and weaving process requirements.

[0074] Specifically, the loom control system reads the stored fabric structure file and identifies the pattern data within it. This reading process involves binary streaming parsing of a specialized textile design file, skipping the metadata description area at the file header and directly locating the entity data block containing warp and weft interlacing information. This entity data block is arranged sequentially in bytes, with each byte representing the floating / sinking state of a specific number of warp yarns on a particular weft. The pattern data is discretized according to the interlacing points of the warp and weft yarns to construct a binary matrix of the fabric structure. This process first allocates a two-dimensional integer array space in memory, with the number of rows corresponding to the total number of weft yarns in the pattern data and the number of columns corresponding to the total number of warp yarns. Then, bitwise operations are used to extract the data bit by bit. In the section on state information, within the binary matrix of the fabric structure, the interlacing point where the warp yarns float above the weft yarns is marked with a value of 1, indicating that the warp yarns are in a high potential energy state. The interlacing point where the warp yarns sink below the weft yarns is marked with a value of 0, indicating that the warp yarns are in a low potential energy state. This completes the digital mapping of the entire fabric. Warp yarn parameters are entered through the human-computer interaction interface. These parameters include warp yarn diameter, warp yarn elastic modulus, and warp beam radius. For example, inputting a warp yarn diameter of 0.25 mm, a warp yarn elastic modulus of 500 cN / tex, and an initial warp beam radius of 400 mm on the touchscreen. Based on the warp yarn elastic modulus and weaving process requirements, the target tension value during the weaving process is set. The setting process is calculated based on a modified formula of Hooke's Law to set the target tension. for:

[0075] ;

[0076] in, This represents the set target tension value, expressed in Newtons (N). This value serves as the reference input for subsequent control loops and represents the constant tension level that the warp yarns should maintain under ideal weaving conditions. This indicates the entered warp elastic modulus, in Pascals (Pa). Here, the cN / tex unit in the input interface, combined with the warp density, needs to be converted to the standard pressure unit Pascal using the internal conversion program to unify the physical dimensions. This represents the constant pi, with a value of 3.1415926. It is used to calculate the circular cross-sectional area of ​​yarn in conjunction with its diameter. This constant is stored in the controller's math library for later use. The value represents the recorded warp diameter in millimeters (mm). This value is derived from the average measured value of the yarn sample by a high-precision laser diameter measuring instrument or from the technical specifications provided by the raw material supplier. [2] is the radius calculation constant, used to divide the diameter by 2 to obtain the radius. The preset warp elongation rate, which is dimensionless and for example, is 0.02, is the required elongation rate of the weaving process. This value is set by the process engineer according to the requirements of the fabric style and is used to define the ideal degree of deformation of the yarn under tension.

[1000] is the unit conversion factor, which is used to normalize the calculation results from millineutons or other intermediate units to the international standard unit Newton. Through this calculation, the physical properties of the material are transformed into specific tension value control targets.

[0077] In this embodiment, the steps of analyzing the warp interlacing state corresponding to the current weft yarn in the fabric structure binary matrix and calculating the theoretical warp yarn consumption length in the current weft yarn weaving process based on the warp yarn interlacing state and warp yarn parameters are as follows: Extract one row of data corresponding to the current weft yarn in the fabric structure binary matrix as the current weft yarn row vector; traverse the current weft yarn row vector; count the number of value jumps in the current weft yarn row vector; define the number of jumps as the number of interlacing points; calculate the weaving resistance compensation index based on the number of interlacing points and warp yarn parameters; and calculate the theoretical warp yarn consumption length using the weaving resistance compensation index. The formula for calculating the weaving resistance compensation index is: ,in, This represents the weaving resistance compensation index. Indicates the number of interlacing points. This represents the total number of columns in the binary matrix representing the fabric structure. Indicates the warp diameter in millimeters. This represents the preset first interleaving weight coefficient. The second diameter weighting coefficient is a preset value. Based on the weaving resistance compensation index and combined with geometric trigonometric function relationships, the increased length due to the bending of the warp yarn at the interlacing point is calculated. The increased length is added to the basic width of the fabric to obtain the theoretical warp yarn consumption length.

[0078] Specifically, the data corresponding to the current weft yarn in the fabric structure binary matrix is ​​extracted as the current weft yarn row vector. This is achieved by reading the current weft count value from the loom spindle encoder as an index, addressing and copying the corresponding row data stream from the two-dimensional matrix in memory. The current weft yarn row vector is traversed, and the number of value jumps in the current weft yarn row vector is counted. Specifically, a counter variable is set to an initial value of 0. Starting from the first element of the row vector, adjacent values ​​are compared one by one. If the previous value is 1 and the next value is 0, or the previous value is 0 and the next value is 1, it is determined as an interlacing jump, and the counter is incremented by 1. The number of times is defined as the number of interlacing points. The weaving resistance compensation index is calculated based on the number of interlacing points and the warp parameters. The theoretical warp yarn consumption length is calculated using the weaving resistance compensation index. The formula for calculating the weaving resistance compensation index is:

[0079] ;

[0080] in, The weaving resistance compensation index is a dimensionless comprehensive evaluation coefficient used to quantify the degree of mechanical resistance generated by the shedding movement of the warp yarns during weft weaving. A higher value indicates greater weaving resistance. This indicates the number of interlacing points obtained through statistics. For example, if 3000 interlacing points are counted in a full width of 6000 warp yarns, this value reflects the current weft yarn's structural complexity in real time. This represents the total number of columns in the fabric structure binary matrix, i.e., the total number of warp yarns on the loom, for example, 6000. This parameter is determined during the initialization of the loom parameter settings page and is used to normalize the number of interlacing points. This indicates the warp diameter in millimeters, for example, 0.3mm. This diameter data is directly retrieved from the previously entered warp parameters. The diameter is introduced here because the thicker the yarn, the greater its bending stiffness at the interlacing point, resulting in more significant resistance. This represents the preset first interlacing weight coefficient, with a value of 0.65. This value is derived from regression analysis of a large amount of plain weave experimental data and is used to characterize the weight of the interlacing frequency on resistance. This represents the preset second diameter weighting coefficient, with a value of 0.35, used to characterize the correction weight of yarn thickness on resistance. This is a base-10 logarithmic function used to smooth out the nonlinear effects caused by changes in diameter. To prevent overflow or negative infinity in the logarithmic function calculation when the diameter is extremely small or close to 0, the increased length due to warp bending at the interlacing point is calculated based on the weaving resistance compensation index and combined with geometric trigonometric function relationships. The increased length is then added to the basic width of the fabric to obtain the theoretical warp consumption length.

[0081] In this embodiment, the steps of using a tension sensor to collect the actual warp tension value in real time, calculating the tension deviation between the actual warp tension value and the target tension value, and inputting the tension deviation into a variable universe of discourse fuzzy PID controller for calculation to obtain the feedback adjustment linear velocity are as follows: The actual warp tension value is collected by a tension sensor installed at the back beam of the loom. The actual warp tension value is subtracted from the target tension value to obtain the tension deviation, and the rate of change of the tension deviation over time is calculated. The tension deviation and the rate of change are used as input variables of the variable universe of discourse fuzzy PID controller. The universe of discourse range of the input variables is adjusted in real time using a scaling factor function. When the absolute value of the tension deviation is less than a preset fine-tuning threshold, the universe of discourse range is compressed using the scaling factor function. When the absolute value of the tension deviation is greater than the fine-tuning threshold, the universe of discourse range is expanded using the scaling factor function. Fuzzy inference is performed based on the adjusted universe of discourse range to calculate the correction amount of the PID parameters. The feedback adjustment linear velocity is then calculated using the corrected PID parameters.

[0082] Specifically, the actual warp tension value is collected by a tension sensor installed at the back beam of the loom. The acquisition process uses a strain gauge sensor based on the Wheatstone bridge principle to convert the mechanical pressure of the warp yarn on the back beam into a weak voltage signal. This signal is then converted into a digital signal by a high-precision 24-bit analog-to-digital converter at a sampling frequency of 2000Hz. A moving average filter is then applied to eliminate environmental noise interference. The actual warp tension value is subtracted from the target tension value to obtain the tension deviation. The rate of change of the tension deviation over time is calculated by subtracting the deviation value from the previous sampling time from the current sampling value and dividing by the sampling time interval (0.0005 seconds) to obtain the first derivative of the deviation. The tension deviation and its rate of change are used as input variables for a variable universe of discourse fuzzy PID controller. The universe of discourse of the input variables is adjusted in real time using a scaling factor function. When the absolute value of the tension deviation is less than a preset fine-tuning threshold (e.g., less than 5N), the universe of discourse is compressed using the scaling factor function. The calculation is as follows:

[0083] ;

[0084] in, is the compression factor, with a value between 0.5 and 1, used to directly multiply by the boundary value of the universe of discourse to reduce the control range, [1] is the reference constant, representing the original state without compression, This is the maximum compression limit coefficient, indicating that the universe of discourse can be compressed to a maximum of 50% of its original size. This coefficient prevents the universe of discourse from becoming too narrow, which could lead to control instability. Euler's number is a natural constant with a value of approximately 2.71828. It serves as the base of the exponential function and is used to construct the decay curve of the Gaussian distribution. This is the absolute value of the current tension deviation, expressed in Newtons (N), obtained by taking the absolute value of the deviation calculated in real time. The preset fine-tuning threshold is in Newtons (N), for example, 5N. This threshold defines the range of small errors that need to be finely adjusted. [2] is an exponent, used to control the steepness of the Gaussian curve so that the compression factor can decrease smoothly and quickly when the error is close to 0. When the absolute value of the tension deviation is greater than the fine-tuning threshold, the domain range is expanded using the scaling factor function. Multiply the universe of discourse boundary by a coefficient of 1.5 to 3 to cover a larger error range. Perform fuzzy inference based on the adjusted universe of discourse range to calculate the correction amount of the PID parameters. Use the corrected PID parameters to calculate the feedback regulation linear velocity.

[0085] In this embodiment, the steps of performing fuzzy inference based on the adjusted universe of discourse, calculating the correction amount of the PID parameters, and calculating the feedback adjustment linear velocity using the corrected PID parameters are as follows: An asymmetric fuzzy rule table is established in the variable universe of discourse fuzzy PID controller. The sign direction of the tension deviation is determined. If the tension deviation is positive, it indicates that the actual warp tension value is greater than the target tension value. A larger proportional gain parameter is selected according to the asymmetric fuzzy rule table. If the tension deviation is negative, it indicates that the actual warp tension value is less than the target tension value. A smaller integral gain parameter is selected according to the asymmetric fuzzy rule table. The feedback adjustment linear velocity is calculated based on the selected proportional gain parameter and integral gain parameter.

[0086] Specifically, an asymmetric fuzzy rule table is established in the variable universe fuzzy PID controller. This rule table is a 7x7 matrix, where the horizontal axis represents the rate of change of tension deviation and the vertical axis represents the tension deviation. Each cell stores the adjustment instructions for the PID parameters. The sign of the tension deviation is determined. If the tension deviation is positive, it indicates that the actual tension value of the warp yarn is greater than the target tension value. In this case, the warp yarn is too tight, posing a risk of yarn breakage. Therefore, a larger proportional gain parameter is selected according to the asymmetric fuzzy rule table, for example, the base proportional gain is increased. Multiply by a coefficient of 1.5 to 2.0 to rapidly accelerate the warp feed motor and deliver the warp yarn to release tension. If the tension deviation is negative, it indicates that the actual tension of the warp yarn is less than the target tension value. In this case, the warp yarn is slightly loose, but it will not cause immediate physical damage. Therefore, a smaller integral gain parameter is selected based on the asymmetric fuzzy rule table, for example, by adjusting the base integral gain. Multiply by a coefficient of 0.5 to 0.8 and limit the differential output amplitude. This is to prevent the warp yarns from loosening and knotting due to drastic deceleration or reverse rotation of the warp feed motor. The feedback adjustment linear velocity is calculated based on the selected proportional gain and integral gain parameters using a discretized PID formula.

[0087] ;

[0088] in, This represents the calculated feedback adjustment linear velocity, expressed in millimeters per second (mm / s), and is the final output of the controller. This represents the proportional gain parameter corrected according to the fuzzy rule table, used in response to the current error magnitude. Indicates the current number The tension deviation value at each sampling time, in Newtons (N). This indicates the current discrete-time sampling number. This represents the integral gain parameter after correction according to the fuzzy rule table, used to eliminate steady-state error. The summation symbol represents the accumulation of historical deviations. The starting time of the accumulation operation is the control start time. For the index variable of historical sampling points, This indicates the control cycle, in seconds (s), for example, 0.001 seconds. This value is determined by the controller's main frequency and timer interrupt settings. This represents the differential gain parameter, corrected according to the fuzzy rule table, used to predict the trend of error changes. Indicates the previous sampling time The tension deviation value is used to calculate the rate of change in conjunction with the current deviation. This asymmetric adjustment logic ensures that the tension control has different response characteristics in the "loose" and "tight" directions.

[0089] In this embodiment, the steps of calculating the dynamic feedforward compensation linear speed of the warp feed motor based on the rate of change of the theoretical warp yarn consumption length, correcting the feedback adjustment linear speed using the dynamic feedforward compensation linear speed, and generating the final warp feed linear speed command are as follows: storing the historical theoretical warp yarn consumption length calculated during the previous weft yarn weaving, calculating the difference between the theoretical warp yarn consumption length and the historical theoretical warp yarn consumption length to obtain the single weft yarn consumption increment, dividing the single weft yarn consumption increment by the time required for the loom spindle to rotate one revolution to obtain the corresponding linear speed increment, defining the linear speed increment as the dynamic feedforward compensation linear speed, directly superimposing the dynamic feedforward compensation linear speed and the feedback adjustment linear speed to obtain the superimposed bus speed, performing amplitude limiting processing on the superimposed bus speed, and using the speed after amplitude limiting processing as the final warp feed linear speed command.

[0090] Specifically, the historical theoretical warp yarn consumption length calculated during the previous weft weaving is stored. This requires maintaining a circular queue in the controller's non-volatile memory. Each completed weft weaving operation pushes the currently calculated consumption length into the queue. The difference between the theoretical warp yarn consumption length and the historical theoretical warp yarn consumption length is calculated to obtain the single-weft yarn consumption increment. This increment reflects the sudden change in demand caused by changes in the fabric structure. Dividing the single-weft yarn consumption increment by the time required for the loom spindle to rotate one revolution yields the corresponding linear speed increment. The time required for the spindle to rotate one revolution is calculated from the real-time speed feedback of the spindle encoder. For example, if the current speed is 600 rpm, then one revolution takes 0.1 seconds. If the yarn consumption increment is 2 mm, the linear speed increment is 20 mm / s. The linear speed increment is defined as the dynamic feedforward compensation linear speed. The dynamic feedforward compensation linear speed is directly superimposed with the feedback adjustment linear speed to obtain the superimposed bus speed. The superimposed bus speed is subjected to amplitude limiting processing. The bus speed is compared with the preset physical limit speed range of the motor. For example, the maximum warp feed linear speed is set to 3000 mm / s. This limit value is calculated based on the torque-speed characteristic curve of the warp feed motor and the transmission ratio of the reducer. If the superimposed result exceeds this value, it is forcibly truncated to 3000 mm / s. The speed after amplitude limiting processing is used as the final warp feed linear speed command.

[0091] In this embodiment, the specific steps for directly superimposing the dynamic feedforward compensation linear velocity and the feedback adjustment linear velocity to obtain the superimposed bus velocity are as follows: monitoring the angle position signal of the loom spindle; when the angle position signal is detected to be within a preset angle window before the weft insertion action occurs, triggering the speed superposition operation; within the preset angle window, superimposing the dynamic feedforward compensation linear velocity onto the feedback adjustment linear velocity in the form of pulses; through the speed superposition operation, before the warp tension fluctuates drastically due to the weft insertion action, the speed of the warp feed motor is changed in advance to counteract the tension interference caused by the change in the fabric structure, and the superimposed bus velocity is output.

[0092] Specifically, the angular position signal of the loom spindle is monitored. An absolute encoder connected to the spindle reads the angle value from 0 to 360 degrees in real time. When the angular position signal is detected to be within the preset angle window before the weft insertion action, for example, if the weft insertion point is set to 360 degrees (0 degrees), the preset angle window is set to between 300 and 350 degrees. This range corresponds to the period when the reed is about to contact the weft but has not yet made a violent impact. The speed superposition operation is triggered. Within the preset angle window, the dynamic feedforward compensation linear speed is superimposed on the feedback adjustment linear speed in the form of pulses. Specifically, when the spindle angle enters 300 degrees, the calculated feedforward speed value is directly added to the original PID feedback speed command, and this superposition value is maintained until the spindle angle leaves 350 degrees. Through the speed superposition operation, the speed of the warp feed motor is changed in advance before the warp tension fluctuates violently due to the weft insertion action. For example, the warp feed is accelerated in advance when the yarn consumption is detected to increase, so as to counteract the tension interference caused by the change in the fabric structure. The superimposed bus speed is output.

[0093] In this embodiment, the warp parameters include the warp beam radius. The specific steps for controlling the operation of the warp feed motor according to the final warp feed speed command to achieve adaptive adjustment of weaving tension are as follows: using the formula... The final warp feed linear speed command is converted into the target angular velocity of the warp feed motor, where This is the final warp speed command. The radius of the warp beam. To determine the target angular velocity of the warp feed motor, the target angular velocity is sent to the warp feed motor via a servo driver. The warp feed motor drives the warp beam to rotate according to the target angular velocity, releasing or rewinding the warp yarn. During the operation of the warp feed motor, the actual speed and position feedback of the warp feed motor are monitored in real time. The inner loop speed control circuit ensures that the actual speed of the warp feed motor strictly follows the target angular velocity. By changing the amount of warp yarn fed through the action of the warp feed motor, the actual tension value of the warp yarn is made close to the target tension value.

[0094] Specifically, using formulas The final warp feed linear speed command is converted into the target angular velocity of the warp feed motor, where This is the final warp feed speed command, measured in millimeters per second (mm / s). This value is calculated by superimposing the aforementioned feedback and feedforward components, and represents the tangential linear velocity of the warp yarn leaving the surface of the weave beam. The target angular velocity of the motor, measured in radians per second (rad / s), is a command variable directly executed by the servo control system. During calculation, it needs to be... Divide by get , The warp beam radius, measured in millimeters (mm), gradually decreases as the weaving process progresses. The current real-time radius is obtained through real-time measurement or estimation based on yarn consumption integration. For example, the initial full beam radius is 400mm, gradually decreasing to 100mm as the warp yarns are fed out. The target angular velocity of the warp feed motor is sent to the warp feed motor via a servo driver. Communication uses the EtherCAT industrial real-time bus protocol to ensure command transmission latency is less than 1 millisecond. The warp feed motor drives the warp beam to rotate according to the target angular velocity, releasing or rewinding the warp yarns. During the operation of the warp feed motor, the actual speed and position feedback of the motor are monitored in real time. The motor's built-in high-resolution encoder provides feedback on the current rotor position and speed. An inner-loop speed control loop ensures that the actual speed of the warp feed motor strictly follows the target angular velocity. The inner loop uses a PI control algorithm to adjust the stator current frequency. By changing the warp yarn feed amount through the actions of the warp feed motor, the actual warp tension value approaches the target tension value.

[0095] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for adaptive adjustment of weaving tension, characterized in that, Includes the following steps: Obtain the current fabric structure file and warp parameters of the loom, parse the fabric structure file to generate a fabric structure binary matrix, and set the target tension value according to the warp parameters; Analyze the warp yarn interlacing state corresponding to the current weft yarn in the fabric structure binary matrix, and calculate the theoretical warp yarn consumption length in the current weft yarn weaving process based on the warp yarn interlacing state and the warp yarn parameters; The actual tension value of the warp yarn is collected in real time using a tension sensor. The tension deviation between the actual tension value of the warp yarn and the target tension value is calculated. The tension deviation is input into a variable domain fuzzy PID controller for calculation to obtain the feedback adjustment linear velocity. The dynamic feedforward compensation linear speed of the warp feed motor is calculated based on the rate of change of the theoretical warp yarn consumption length. The feedback adjustment linear speed is then corrected using the dynamic feedforward compensation linear speed to generate the final warp feed linear speed command. The operation of the warp feed motor is controlled according to the final warp feed speed command to achieve adaptive adjustment of weaving tension.

2. The weaving tension adaptive adjustment method according to claim 1, characterized in that, The steps of obtaining the current fabric structure file and warp parameters of the loom, parsing the fabric structure file to generate a fabric structure binary matrix, and setting the target tension value according to the warp parameters are as follows: The fabric structure file stored in the loom control system is read, and the pattern data in the fabric structure file is identified. The pattern data is discretized according to the interlacing points of the warp and weft yarns to construct the binary matrix of the fabric structure; In the fabric structure binary matrix, the interlacing point where the warp yarns are above the weft yarns is marked with a value of 1, and the interlacing point where the warp yarns are below the weft yarns is marked with a value of 0. The warp parameters are entered through a human-computer interaction interface. The warp parameters include warp diameter, warp elastic modulus, and warp beam radius. Based on the elastic modulus of the warp yarns and the weaving process requirements, the target tension value is set during the weaving process.

3. The weaving tension adaptive adjustment method according to claim 1, characterized in that, The specific steps for analyzing the warp interlacing state corresponding to the current weft yarn in the fabric structure binary matrix, and calculating the theoretical warp yarn consumption length in the current weft yarn weaving process based on the warp interlacing state and the warp yarn parameters are as follows: Extract the row of data corresponding to the current weft yarn in the binary matrix of the fabric structure as the current weft yarn row vector; Traverse the current weft yarn row vector, count the number of times the value in the current weft yarn row vector jumps, and define the number of times as the number of interlacing points; The weaving resistance compensation index is calculated based on the number of interlacing points and the warp parameters, and the theoretical warp consumption length is calculated using the weaving resistance compensation index. The formula for calculating the weaving resistance compensation index is as follows: ； in, This represents the weaving resistance compensation index. Indicates the number of interlacing points. This represents the total number of columns in the binary matrix of the fabric structure. The diameter of the warp yarn is expressed in millimeters. This represents the preset first interleaving weight coefficient. This represents the preset second diameter weighting coefficient; Based on the weaving resistance compensation index and combined with geometric trigonometric function relationships, the increased length due to the bending of the warp yarn at the interlacing point is calculated. The increased length is then added to the basic width of the fabric to obtain the theoretical warp yarn consumption length.

4. The weaving tension adaptive adjustment method according to claim 1, characterized in that, The specific steps for obtaining feedback adjustment of linear velocity by using a tension sensor to collect the actual warp tension value in real time, calculating the tension deviation between the actual warp tension value and the target tension value, and inputting the tension deviation into a variable universe fuzzy PID controller for calculation are as follows: The actual tension value of the warp yarn is collected by the tension sensor installed at the rear beam of the loom. The tension deviation is obtained by subtracting the target tension value from the actual tension value of the warp yarn, and the rate of change of the tension deviation over time is calculated. The tension deviation and the rate of change are used as input variables for the variable universe fuzzy PID controller; The domain range of the input variables is adjusted in real time using a scaling factor function; When the absolute value of the tension deviation is less than the preset fine-tuning threshold, the domain range is compressed using the scaling factor function; When the absolute value of the tension deviation is greater than the fine-tuning threshold, the domain range is expanded using the scaling factor function; Fuzzy inference is performed based on the adjusted universe of discourse to calculate the correction amount of the PID parameters, and the feedback regulation linear velocity is calculated using the corrected PID parameters.

5. The weaving tension adaptive adjustment method according to claim 4, characterized in that, The specific steps for performing fuzzy inference based on the adjusted universe of discourse, calculating the correction amount of the PID parameters, and using the corrected PID parameters to calculate the feedback regulation linear velocity are as follows: An asymmetric fuzzy rule table is established in the variable universe fuzzy PID controller; Determine the sign and direction of the tension deviation; If the tension deviation is positive, it indicates that the actual tension value of the warp yarn is greater than the target tension value. Then, a larger proportional gain parameter is selected according to the asymmetric fuzzy rule table. If the tension deviation is negative, it indicates that the actual tension value of the warp yarn is less than the target tension value. Then, a smaller integral gain parameter is selected according to the asymmetric fuzzy rule table. The feedback adjustment linear velocity is calculated based on the selected proportional gain parameter and integral gain parameter.

6. The weaving tension adaptive adjustment method according to claim 1, characterized in that, The specific steps for calculating the dynamic feedforward compensation linear speed of the warp feed motor based on the theoretical rate of change of warp yarn consumption length, correcting the feedback adjustment linear speed using the dynamic feedforward compensation linear speed, and generating the final warp feed linear speed command are as follows: Store the historical theoretical warp yarn consumption length calculated during the weaving of the previous weft yarn; Calculate the difference between the theoretical warp yarn consumption length and the historical theoretical warp yarn consumption length to obtain the single weft yarn consumption increment; Divide the single-weft yarn consumption increment by the time required for the loom spindle to rotate one revolution to obtain the corresponding linear velocity increment; The linear velocity increment is defined as the dynamic feedforward compensation linear velocity; The dynamic feedforward compensation linear velocity and the feedback adjustment linear velocity are directly superimposed to obtain the superimposed bus velocity. The superimposed bus speed is subjected to amplitude limiting processing, and the speed after amplitude limiting is used as the final warp feed line speed command.

7. The weaving tension adaptive adjustment method according to claim 6, characterized in that, The specific steps for directly superimposing the dynamic feedforward compensation linear velocity and the feedback adjustment linear velocity to obtain the superimposed bus velocity are as follows: Monitor the angular position signal of the loom spindle; When the angle position signal is detected to be within a preset angle window before the weft insertion action occurs, a speed superposition operation is triggered. Within the preset angle window, the dynamic feedforward compensation linear velocity is superimposed on the feedback adjustment linear velocity in the form of pulses; By performing the speed superposition operation, the rotational speed of the warp feed motor is changed in advance before the warp tension fluctuates drastically due to the weft insertion action, so as to counteract the tension interference caused by the change in the fabric structure and output the superimposed bus speed.

8. The weaving tension adaptive adjustment method according to claim 1, characterized in that, The warp parameters include the warp beam radius; the specific steps for controlling the operation of the warp feed motor according to the final warp feed speed command to complete the adaptive adjustment of weaving tension are as follows: Using formula The final warp feed linear speed command is converted into the target angular velocity of the warp feed motor, wherein This refers to the final warp feed line speed command. The radius of the weaving beam. The target angular velocity of the feed motor; The target angular velocity of the warp feed motor is sent to the warp feed motor via a servo driver; The warp feed motor drives the warp beam to rotate according to the target angular velocity of the warp feed motor, thereby releasing or rewinding the warp yarns; During the operation of the yarn feeding motor, the actual speed and position feedback of the yarn feeding motor are monitored in real time; The inner loop speed control circuit ensures that the actual speed of the warp-feeding motor strictly follows the target angular velocity of the warp-feeding motor. By changing the amount of warp yarn fed by the operation of the warp feed motor, the actual tension value of the warp yarn is made to approach the target tension value.

9. The system of the adaptive weaving tension adjustment method according to any one of claims 1-8, characterized in that, include: The fabric data parsing module is used to obtain the current fabric structure file and warp parameters of the loom, parse the fabric structure file to generate a fabric structure binary matrix, and set the target tension value according to the warp parameters. The warp yarn consumption calculation module is used to analyze the warp yarn interlacing state corresponding to the current weft yarn in the fabric structure binary matrix, and calculate the theoretical warp yarn consumption length in the current weft yarn weaving process based on the warp yarn interlacing state and the warp yarn parameters. The tension detection and control module is used to collect the actual tension value of the warp yarn in real time using a tension sensor, calculate the tension deviation between the actual tension value of the warp yarn and the target tension value, and input the tension deviation into a variable domain fuzzy PID controller for calculation to obtain feedback adjustment of the linear velocity. The feedforward compensation module is used to calculate the dynamic feedforward compensation linear speed of the warp feed motor based on the rate of change of the theoretical warp consumption length, and to use the dynamic feedforward compensation linear speed to correct the feedback adjustment linear speed, thereby generating the final warp feed linear speed command. The execution control module is used to control the operation of the warp feed motor according to the final warp feed speed command, so as to complete the adaptive adjustment of weaving tension.

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