Intelligent control system for wire harness production process

Abstract

The invention relates to the technical field of intelligent control, in particular to an intelligent control system for a wire harness production process, which comprises a path constraint analysis module, a tension balance regulation and control module, an instantaneous springback measurement module, a cutting offset compensation module and a dynamic error correction module. According to the method, the geometric feature data of the wiring harness laying path are collected and the stress distribution state is accurately calculated, so that the refinement of stress analysis of the wiring harness in the laying process is remarkably improved, the deviation between the actual tension of the wiring harness and the stress distribution of the path is monitored in real time, the tension is dynamically adjusted, and the balance control of the tension is realized; the problem of deformation or relaxation caused by abnormal local tension is effectively prevented, deformation monitoring of the cutting position is combined with instantaneous rebound characteristic analysis, the accuracy of the size after cutting is ensured, error accumulation caused by rebound is reduced, the cutting precision is improved by calculating the offset of the cutting position and conducting cutting compensation adjustment, and the cutting quality is improved. And therefore, the processing consistency and the assembly adaptability of the wire harness can be improved.

Description

Technical Field

[0001] The present invention relates to the field of intelligent control technology, and in particular to an intelligent control system for a wire harness production process. Background Art

[0002] The field of intelligent control technology includes automatic control, intelligent perception, data processing and adaptive optimization, and is widely used in industrial manufacturing, traffic management, smart home and other industries. The core content is to achieve real-time monitoring and adjustment of production processes, equipment operating status and environmental parameters through computer control, sensor technology and embedded systems. The systematic nature of intelligent control technology is mainly reflected in the use of actuators to accurately control the target object based on sensor information collection, data processing and decision calculation to ensure the stability and efficient operation of the system. At present, the development trend of this technology field is focused on combining artificial intelligence, edge computing and Internet of Things technologies to enhance the system's autonomous learning and optimization capabilities to achieve a higher level of automated control and resource allocation.

[0003] Among them, the intelligent control system for the wire harness production process refers to a system used to intelligently control each process link in the wire harness manufacturing process, mainly covering wire cutting, terminal crimping, wire harness assembly and quality inspection and other links. The PLC control unit controls the cutting machine, crimping machine and automatic assembly equipment, and combines visual inspection equipment to monitor the terminal crimping quality and wire harness arrangement status in real time. The production equipment is connected through the industrial bus or field bus, and the preset process parameters and inspection standards are used to automatically adjust the cutting length, pressure and assembly sequence, and record production data through the storage unit. According to the needs of different types of wire harnesses, the corresponding processing requirements can also be adapted through parameter adjustment to achieve intelligent control of the production process.

[0004] In the existing production process of wire harnesses, the force distribution of the path cannot be accurately identified during the wiring harness layout process, which leads to uneven force at bending points, intersections and friction-affected areas, which in turn causes local stretching, relaxation or breakage of the wire harness, affecting the layout quality and subsequent processing accuracy. Due to the lack of real-time monitoring and dynamic adjustment of tension changes, there may be tension deviations in the wire harness at different layout stages, which can easily cause tension mutations or imbalances, affecting the overall stability of the wire harness. For the dimensional accuracy control after cutting, it only relies on preset process parameters for cutting, and does not consider the instantaneous rebound characteristics of the wire harness during the cutting process, resulting in the accumulation of cutting errors, which increases the dimensional deviation of the wire harness processing and affects the accuracy of terminal crimping and subsequent assembly. In addition, the lack of real-time monitoring of cutting compensation strategies makes it difficult to effectively correct the cutting offset problem caused by rebound, affecting the production consistency of the wire harness and reducing the processing quality and assembly adaptability. Summary of the invention

[0005] The purpose of the present invention is to solve the shortcomings in the prior art and to propose an intelligent control system for the production process of electric wire harnesses.

[0006] In order to achieve the above object, the present invention adopts the following technical solution: an intelligent control system for the production process of electric wire harnesses comprises: The path constraint analysis module collects the bending angle, curvature change, and intersection position in the wiring harness layout path, calculates the force distribution state of the wiring harness in the path, analyzes the influence of friction on the change of the wiring harness layout tension, and obtains the path force distribution; The tension balance control module analyzes the actual tension changes of the wire harness at different layout positions according to the force distribution of the path, uses the tension sensor to detect the real-time force of the wire harness, calculates the deviation between the actual tension and the force distribution of the path, dynamically adjusts the tension of the wire harness to make the tension of the wire harness uniform, and obtains the tension balance adjustment result; The instantaneous rebound determination module monitors the deformation of the wire harness at the cutting position according to the tension balance adjustment result, analyzes the instantaneous rebound of the wire harness after stretching, determines the influence of the force on the rebound trend of the wire harness, reveals the rebound characteristics of the cutting point, and obtains the rebound trend data of the wire harness; The cutting offset compensation module analyzes the size error caused by the springback of the wire harness during the cutting process according to the springback trend data of the wire harness, detects the size of the wire harness after cutting, calculates the offset of the cutting position, and obtains the cutting compensation adjustment amount of the wire harness.

[0007] As a further solution of the present invention, the path force distribution includes force change data at bends, force change data at intersections, friction influence areas, and tension easy-to-change areas; the tension equalization adjustment results include real-time tension distribution records, tension deviation amounts, and tension adjustment parameters; the wire harness rebound trend data include rebound deformation amounts, rebound directions, and rebound influence factors; the wire harness cutting compensation adjustment amounts include cutting offset amounts, cutting error correction values, and cutting size adjustment parameters.

[0008] As a further solution of the present invention, the path constraint analysis module includes: The geometric feature extraction submodule obtains the spatial coordinate data of the wiring harness routing path, detects the bending angle, curvature change, and intersection position in the path, calculates the curvature radius and bending angle at each position, calculates the curvature change rate of each segment of the path based on the spatial coordinate points, identifies the three-dimensional position of the intersection, calls the curvature change rate and bending angle of the path, and obtains the path geometric feature parameters; The force state calculation submodule calculates the friction and tension distribution of each section of the path based on the path geometric characteristic parameters, calculates the ratio of friction to angle change for the bending point and intersection area, and evaluates the force characteristics of different areas of the path using the formula: ; Calculation of bending force coefficient ,in, Representative path The tension of the segment, Represents the bending angle of the path. represents the radius of curvature of this segment of the path, represents the friction coefficient of the segment, Indicates the number of path segments; The path force distribution analysis submodule combines the bending force coefficient to analyze the locations where the tension in different areas of the path is prone to change, combines the influencing factors of path friction, calculates the tension fluctuation range of each point, evaluates the sensitive areas of sudden tension changes on the path, and obtains the path force distribution.

[0009] As a further solution of the present invention, the tension balance control module includes: The tension detection submodule obtains the force distribution of the path, monitors the real-time tension of the wire harness at different layout positions, calls the force data measured by the tension sensor, analyzes the tension state of each position, calculates the tension balance of each point, and obtains real-time tension distribution data; The tension deviation calculation submodule calculates the deviation between the actual tension at each point and the path force distribution based on the real-time tension distribution data, analyzes the tension change trend, and uses the formula: ; Calculate the relative deviation ratio of tension at each point , obtain tension deviation data, where, Representative Real-time tension of each measuring point, Represents the reference tension of the corresponding measuring point in the path force distribution, Represents the number of measuring points; The tension dynamic adjustment submodule analyzes the area where the tension of the wire harness is uneven according to the tension deviation data, calculates the tension increments that need to be adjusted in different areas, regulates the tension of the wire harness to promote tension balance, and obtains a tension balance adjustment result.

[0010] As a further solution of the present invention, the instantaneous rebound determination module includes: The deformation monitoring submodule monitors the length change of the wire harness at the cutting position under the force according to the tension balance adjustment result, collects the length data before stretching and at the moment of cutting, compares the deformation of each section of the wire harness, calculates the relative elongation at the cutting position, and obtains the deformation value of the cutting area; The springback analysis submodule analyzes the retraction change of the wire harness after the release of the tension based on the deformation value of the cutting area, obtains the retraction length, initial tension, release speed, and cross-sectional mass sampling data at the moment of cutting and in a short period of time after release, and compares the deformation difference and force change at different time points. The formula is used: ; Calculate the rebound response amplitude value , and analyze the rebound response intensity distribution, where Indicates the wiring harness The retraction length of the cutting point at the moment of release, Indicates The tension sampling value before the point is released. Indicates The total length change value under the point stretching state, Indicates The cross-section quality sampling value at the point cutting position, Indicates The instantaneous speed sampling value of the point tension release, Indicates the total number of cutting points; The trend data generation submodule analyzes the degree of rebound response at each point based on the rebound response amplitude value, combined with the tension change and release speed of the cutting point, determines the instantaneous rebound strength trend of the cutting area, calculates the response fluctuation amplitude of the cutting area, and obtains the wire harness rebound trend data.

[0011] As a further solution of the present invention, the cropping offset compensation module includes: The springback error analysis submodule extracts the instantaneous deformation variation of the cutting point according to the springback trend data of the wire harness, analyzes the cutting size error caused by the instantaneous springback, and quantifies the error offset of different points by combining the time point comparison and the deformation data variation to obtain the springback error offset value; The cutting size detection submodule detects the actual length data of the end of the wire harness after cutting according to the rebound error offset value, compares the difference between the target length and the measured length before and after cutting, selects the points where the error exceeds the offset threshold, and obtains the cutting length deviation; The compensation adjustment amount calculation submodule performs correction calculation based on the cutting length deviation, combined with the error direction, the start and end positions of the error section, the tension release time after cutting and other observations, using the formula: ; Calculate wire harness cut compensation adjustment ,in, Indicates The actual length after cutting at the cutting point. Indicates the target reference length of the corresponding point. Indicates the rebound trend value of the corresponding point, Indicates the duration of tension after the cutting at this point is released.

[0012] As a further solution of the present invention, the system further includes a dynamic error correction module; The dynamic error correction module adjusts the cutting unit to perform error correction according to the wire harness cutting compensation adjustment amount, analyzes the size error change after cutting, counts the actual situation of the wire harness size error, and reviews the wire harness size after cutting. If there is an error, the compensation adjustment amount is recalculated for dynamic correction.

[0013] As a further solution of the present invention, the dynamic error correction module includes: The error adjustment submodule adjusts the positioning structure and cutting path of the cutting unit according to the wire harness cutting compensation adjustment amount, collects the control instruction parameters before and after the cutting unit executes, adjusts the starting coordinates and offset distance of the cutting position, matches the compensation value with the cutting reference plane position, and obtains the cutting execution adjustment value; The error verification submodule detects the actual length data of the wire harness after cutting based on the cutting execution adjustment value, collects the cutting length and set size of each section of the wire harness, counts the error value and offset direction of each section, determines whether there is a point that exceeds the cutting error reference range, and obtains the cutting size error value; The compensation recalculator module selects the cutting segments with errors exceeding the range according to the cutting size error value, calculates the correction data based on the offset direction, error point location distribution, and error change amplitude, reconstructs the offset control parameters of the execution instructions of each cutting unit, and obtains the dynamic correction compensation value.

[0014] Compared with the prior art, the advantages and positive effects of the present invention are: In the present invention, by collecting the geometric feature data of the wiring harness layout path and accurately calculating the force distribution state, the refinement of the force analysis of the wiring harness during the layout process is significantly improved, making the path optimization more reasonable, and real-time monitoring of the deviation between the actual tension of the wiring harness and the path force distribution, and dynamically adjusting the pulling force to achieve balanced tension control, effectively preventing deformation or relaxation problems caused by abnormal local tension, and monitoring the deformation amount at the cutting position combined with the analysis of the instantaneous rebound characteristics to ensure the accuracy of the size after cutting and reduce the error accumulation caused by rebound. By calculating the cutting position offset and performing cutting compensation adjustment, the cutting accuracy is improved, thereby improving the consistency of wire harness processing and the assembly adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a system flow chart of the present invention; Figure 2 This is a flow chart of the path constraint analysis module of the present invention; Figure 3 This is a flow chart of the tension balance control module of the present invention; Figure 4 This is a flow chart of the instantaneous rebound determination module of the present invention; Figure 5 This is a flow chart of the cutting offset compensation module of the present invention; Figure 6 This is a flow chart of the dynamic error correction module of the present invention. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0017] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, in the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0018] See also Figure 1 , an intelligent control system for the production process of electric wire harnesses includes: The path constraint analysis module obtains the geometric feature data of the wiring harness routing path, detects the bending angle, curvature change, and intersection position in the path, analyzes the friction influence in different areas, determines the stress state of the wiring harness during the routing process, calculates the stress changes at the bends and intersections, identifies the areas where the tension of the wiring harness is prone to change, and obtains the path stress distribution; The tension balance control module analyzes the actual tension changes of the wire harness at different layout positions according to the force distribution of the path, uses the tension sensor to detect the real-time force of the wire harness, calculates the deviation between the actual tension and the force distribution of the path, dynamically adjusts the tension of the wire harness to make the tension of the wire harness uniform, and obtains the tension balance adjustment result; The instantaneous rebound measurement module monitors the deformation of the wire harness at the cutting position according to the tension balance adjustment result, analyzes the instantaneous rebound of the wire harness after stretching, determines the influence of the force on the rebound trend of the wire harness, reveals the rebound characteristics of the cutting point, and obtains the rebound trend data of the wire harness; The cutting offset compensation module analyzes the size error caused by the springback of the wire harness during the cutting process according to the springback trend data of the wire harness, detects the size of the wire harness after cutting, calculates the offset of the cutting position, and obtains the cutting compensation adjustment amount of the wire harness; The dynamic error correction module adjusts the cutting unit to correct the error according to the wire harness cutting compensation adjustment amount, analyzes the size error change after cutting, counts the actual situation of the wire harness size error, and reviews the wire harness size after cutting. If there is an error, the compensation adjustment amount is recalculated for dynamic correction.

[0019] The path force distribution includes the force change data at the bends, the force change data at the intersections, the friction influence area, and the tension easily changing area; the tension equalization adjustment results include the real-time tension distribution record, the tension deviation, and the tension adjustment parameters; the wire harness rebound trend data includes the rebound deformation, the rebound direction, and the rebound influence factor; the wire harness cutting compensation adjustment includes the cutting offset, the cutting error correction value, and the cutting size adjustment parameters.

[0020] See also Figure 2 , the path constraint analysis module includes: The geometric feature extraction submodule obtains the spatial coordinate data of the wiring harness routing path, detects the bending angle, curvature change, and intersection position in the path, calculates the curvature radius and bending angle at each position, calculates the curvature change rate of each segment of the path based on the spatial coordinate points, identifies the three-dimensional position of the intersection, calls the curvature change rate and bending angle of the path, and obtains the path geometric feature parameters; When obtaining the spatial coordinate data of the wiring harness routing path, high-precision measurement equipment, such as a laser scanner or a 3D imaging system, is required to measure the coordinate points on the path point by point and record the spatial position of each point. Assuming that the wiring harness path contains 50 key points, the 3D coordinates of each point can be expressed as , as shown in Table 1.

[0021] Table 1 Wire harness path coordinate point data: ; As shown in Table 1, the coordinates of each point are used to calculate the curvature and bending angle, curvature radius The calculation method is: ; For a specific example, suppose the 10th point , the 11th point , enter the formula to calculate: ; After calculation, we get mm. Repeat the calculation of the curvature radius of all points to obtain the path geometric characteristic parameters.

[0022] The force state calculation submodule calculates the friction and tension distribution of each section of the path based on the path geometric characteristic parameters. For the bending points and intersection areas, it calculates the ratio of friction to angle change, and evaluates the force characteristics of different areas of the path using the formula: ; Calculation of bending force coefficient ,in, Representative path The tension of the segment, Represents the bending angle of the path. represents the radius of curvature of this segment of the path, represents the friction coefficient of the segment, Indicates the number of path segments; Based on the path geometric characteristic parameters, the friction and tension distribution of each path segment are calculated. The friction calculation is based on the friction coefficient and tension ,The friction coefficient of the path is affected by the material and the contact surface, as shown in Table 2.

[0023] Table 2 Path material friction coefficient table: ; For the bending point and intersection area, calculate the ratio of friction force to angle change, and set the tension At point 20 on the path, the force is 50 N, the path curvature radius is 15 mm, and the friction coefficient is , bending angle , then use the formula to calculate the bending force coefficient, and substitute the data into: ; The calculated bending stress coefficient is 5.89.

[0024] The path force distribution analysis submodule combines the bending force coefficient to analyze the locations where the tension in different areas of the path is prone to change. Combined with the factors affecting the path friction, it calculates the tension fluctuation range at each point, evaluates the sensitive areas of sudden tension changes on the path, and obtains the path force distribution. Based on the bending force coefficient, analyze the locations where the tension in different areas of the path is prone to change, combine the factors affecting the path friction, calculate the tension fluctuation range of each point, and set the initial tension of the key points of the path , force change , bending angle , and the calculated bending force coefficient , calculate the force distribution of the path.

[0025] Since the bending force coefficient reflects the force change trend at the bending point, the new tension correction calculation formula is: ; ; ; Calculations show that the tension of the path at intersections and high curvature areas is greatly affected by the bending force coefficient, making the tension change more significant. The tension values ​​in different areas are further statistically analyzed to evaluate the force characteristics of each part of the path and obtain the force distribution of the path.

[0026] See also Figure 3 , the tension balance control module includes: The tension detection submodule obtains the force distribution of the path, monitors the real-time tension of the wire harness at different layout positions, calls the force data measured by the tension sensor, analyzes the tension state of each position, calculates the tension balance of each point, and obtains real-time tension distribution data; In the process of laying the wire harness, the tension state at different positions is different. It is necessary to monitor the tension at each point in real time and obtain the force distribution data. Specifically, based on the force distribution of the path, multiple monitoring points are arranged by tension sensors. Each monitoring point records the real-time tension value of its location. The arrangement of monitoring points needs to consider the key areas in the wire harness path, including bending points, intersections and straight segments. Assuming that the total length of the wire harness is 10m, a monitoring point is set up every 1m, then there are a total of 10 monitoring points. Each monitoring point collects the tension value in real time, as shown in Table 3. In the initial state, the tension data of each monitoring point fluctuates between 50N and 120N. The maximum value appears in the intersection area of ​​the path, and the minimum value is in the straighter area of ​​the path. The monitoring data is transmitted to the data processing unit in real time. The tension balance of different areas of the path is calculated based on the measured data, and the tension level of each area is calculated using the mean value. For a certain section, assuming that the tension values ​​measured in the section are 80N, 85N, and 90N respectively, the average tension of the section is: ; As shown in Table 3, the tension data of each measuring point is recorded for subsequent deviation calculation.

[0027] Table 3 Real-time tension data of monitoring points: ; As shown in Table 3, the measured tension data reflects the tension distribution state of each segment of the path, where the tension near the intersection is significantly higher than that in other areas, while the tension in the straight line segment is relatively small. This data is used for subsequent deviation calculation.

[0028] The tension deviation calculation submodule calculates the deviation between the actual tension at each point and the path force distribution based on the real-time tension distribution data, analyzes the tension change trend, and uses the formula: ; Calculate the relative deviation ratio of tension at each point , obtain tension deviation data, where, Representative Real-time tension of each measuring point, Represents the reference tension of the corresponding measuring point in the path force distribution, Represents the number of measuring points; Based on the real-time tension data of the monitoring points in Table 3, the tension deviation value of each point is calculated. The deviation calculation uses the reference tension data of the path force distribution for comparison. The path force distribution data can be obtained by theoretical calculation. Assuming that the theoretical tension value of the path force distribution is shown in Table 4 below, the theoretical tension value of each monitoring point is set to 70N~100N. Taking the No. 3 monitoring point as an example, the actual measured tension is 75N, and the corresponding theoretical reference tension is 80N. Then its tension deviation ratio is calculated as follows: ; Table 4 Theoretical reference tension table of monitoring points: ; As shown in Table 4, the point with the highest deviation ratio appears at measuring point 1, with a deviation value of 0.2857, indicating that the actual tension at this point is much lower than the theoretical reference tension, while the deviation value at measuring point 9 is 0.2000, indicating that the tension at this point is much higher than the theoretical reference tension. This data is used for subsequent tension adjustment.

[0029] The tension dynamic adjustment submodule analyzes the area where the wire harness tension is unbalanced based on the tension deviation data, calculates the tension increments that need to be adjusted in different areas, regulates the tension of the wire harness to balance the tension, and obtains the tension balance adjustment result; The tension deviation ratio data calculated in Table 4 is called to analyze the tension deviation in different areas of the path and determine the tension increment that needs to be adjusted. The calculation method is as follows: ; in, To adjust the pull increment, if the deviation ratio Greater than 0, then Take a negative value to reduce tension. Less than 0, then Take a positive value to increase the tension. Taking measuring point 1 as an example, its deviation ratio is 0.2857, and the corresponding adjustment tension increment is calculated as follows: ; That is, the tension at measuring point 1 needs to be increased by 20N to reach the theoretical reference value, and the adjustment tension increment at measuring point 9 is calculated as follows: ; That is, the tension at measuring point No. 9 needs to be reduced by 20N. Through this adjustment, the tension at each point on the path tends to be balanced, and finally the tension balance adjustment result is obtained.

[0030] See also Figure 4 , the instantaneous rebound measurement module includes: The deformation monitoring submodule monitors the length change of the wire harness at the cutting position under the action of force according to the tension balance adjustment result, collects the length data before stretching and at the moment of cutting, compares the deformation of each section of the wire harness, calculates the relative elongation at the cutting position, and obtains the deformation value of the cutting area; According to the tension balance adjustment result, the deformation at the cutting position of the wire harness needs to be obtained. First, the state after the tension balance adjustment is completed is recorded as the initial state. The tension data obtained by the tension adjustment module is used as the reference. The wire harness numbered Z01 is set to have a tension balance value of 12.5N. At this time, laser displacement sensors are arranged 10mm to the left and right of the cutting position for distance measurement. The total length under tension is recorded as mm, the cutting operation is carried out after the tension is maintained for 3 seconds, at which time the sensor records the instantaneous length as mm, so the instantaneous tensile deformation at this position is: ; This operation is repeated for multiple layout points in turn, and the stretching length of each cutting section under stress is obtained respectively, and it is judged whether it enters the effective stretching range. The system sets the normal tensile strain range of the wire harness to 0.5% to 4.5%. This numerical range is set based on the standard yield ratio and elastic modulus of the wire harness material. For common PVC-wrapped wire harnesses, this range is equivalent to 0.6mm to 5.4mm (based on a length of 120mm). The above Z01 point 3.6mm is within the effective range, so it is recorded as the effective deformation. The comparative data is shown in Table 5: Table 5 Typical point position variable monitoring table: ; As shown in Table 5, the deformation of point Z03 exceeds the reasonable upper limit and is marked as invalid. When executing each point, attention should be paid to the interference of material thermal expansion and contraction, so constant temperature conditions should be maintained during the recording process (recommended 22°C±1°C). After data collection, the system generates the deformation value of the cutting area for subsequent instantaneous rebound analysis.

[0031] The springback analysis submodule analyzes the retraction change of the wire harness after the release of tension based on the deformation value of the cutting area, obtains the retraction length, initial tension, release speed, and cross-sectional mass sampling data at the moment of cutting and in a short period of time after release, and compares the deformation difference and force change at different time points. The formula is used: ; Calculate the rebound response amplitude value , and analyze the rebound response intensity distribution, where Indicates the wiring harness The retraction length of the cutting point at the moment of release, Indicates The tension sampling value before the point is released. Indicates The total length change value under the point stretching state, Indicates The cross-section quality sampling value at the point cutting position, Indicates The instantaneous speed sampling value of the point tension release, Indicates the total number of cutting points; Based on the deformation value of the cutting area, it is necessary to analyze the response characteristics of each wire harness segment during the short-term retraction process after the tension is released, and collect the deformation value before the cutting instant release. , Retract length within 0.5 seconds after cutting , and collect the tension value before the tension is released , Section quality and release speed Conduct a combined assessment.

[0032] Taking the point numbered Z01 as an example, its parameters are sampled as follows: mm; N; mm; g=0.0023kg; m / s.

[0033] Calculate the numerator: ; Calculate the denominator: ; Compute the squared term: ; If the calculated values ​​of the other two points are 3980.2 and 4521.7, then the final result is: ; The preset rebound response amplitude value refers to the previous samples. The median value is set to 100 and the benchmark value is 120. Then 113.13 belongs to the middle interval, indicating that the tension release and structural shrinkage are relatively coordinated, and the numerical results directly correspond to the rebound response amplitude value.

[0034] The trend data generation submodule analyzes the degree of rebound response at each point based on the rebound response amplitude value, combined with the tension change and release speed of the cutting point, determines the instantaneous rebound strength trend of the cutting area, calculates the response fluctuation amplitude of the cutting area, and obtains the wire harness rebound trend data; According to the rebound response amplitude value, the rebound trend of each layout area is further judged in combination with the tension release speed and the evolution trend of the deformation. If the rebound amplitude difference between adjacent layout points (such as Z01-Z02) exceeds the set threshold (set to ±15 units in this system), the area is marked as "rebound unstable area". For example, Z01 is 113.13 and Z02 is 91.5. The difference between the two is 21.63, which exceeds the threshold. Therefore, Z01-Z02 is marked as an unstable rebound segment. For the calculation of the rebound trend, the local average rebound value and the change gradient of the cutting point group are introduced. The calculation method is as follows: Assuming that the rebound values ​​of Z01-Z05 are 113.13, 91.5, 85.2, 120.3, and 109.8 respectively, the local average is: ; The differences between each point and the mean are: +9.14, -12.49, -18.79, +16.31, +5.81. The trend direction is determined according to the difference interval. If the change amplitude of three consecutive points is consistent in direction, it is determined that the trend is linearly increasing or decreasing. This operation is used to obtain the rebound trend data of the wire harness, as shown in Table 6 below: Table 6 Wire harness rebound trend determination table: ; As shown in Table 6, the trends before and after Z03 are reversed, which is identified as a trend mutation point for subsequent tension control strategy adjustment. The final result is the wire harness rebound trend data.

[0035] See also Figure 5 , the cutting offset compensation module includes: The springback error analysis submodule extracts the instantaneous deformation change of the cutting point according to the springback trend data of the wire harness, analyzes the cutting size error caused by instantaneous springback, and quantifies the error offset of different points by combining the time point comparison and the deformation data change to obtain the springback error offset value. According to the wire harness rebound trend data, the rebound response amplitude value needs to be called as the basic data source. This value is usually provided by the previous module after measurement. The parameters used include the instantaneous deformation of the cutting point, the tension release rate, and the retraction length after actual cutting. By collecting the wire harness length change samples during the layout process, sampling is performed at multiple layout points. For example, 8 wire harness cutting points are selected on the layout platform, and the instantaneous retraction lengths after the tension release are recorded as 1.8 mm, 2.0 mm, 1.5 mm, 2.1 mm, 1.9 mm, 2.3 mm, 1.7 mm, and 2.2 mm, respectively. The reference tension, release rate within the time period and other data are compared to obtain the change in the rebound trend. During the execution process, the wire harness rebound error needs to be analyzed based on the trend data, and the reference length of each cutting point is set to 1200 mm, combined with the measured value after retraction. For example, the length measured at the first sampling point is 1198.2 mm, and the preliminary error is 1.8 mm. By recording the error direction, it can be judged as a negative offset. In the process of further refining the error analysis, it is necessary to analyze the specific causes of the error. By comparing the deformation of the wire harness under different tensions in sections, the cutting offset caused by uneven force is separated, and the cutting points with error values ​​greater than ±2.0 mm are selected as abnormal samples. The error of the sixth point is 2.3 mm, which exceeds the offset threshold of ±2.0 mm, which needs to be included in the cutting error compensation range. The cutting offset analysis process needs to quote the instantaneous rate before and after the tension is released. This rate is obtained by measuring the rebound speed of the wire harness within 0.1 seconds after cutting through image recognition. In a typical test platform, the rate fluctuation range is 15 to 25 mm / s. The median value of 20 mm / s is taken as the basis for judging the subsequent error trend direction, further determining whether the error is biased towards contraction or expansion, and correcting the calculation in combination with the initial tension value. The obtained rebound error offset value is the input parameter for subsequent compensation adjustment, and the value ranges from 1.2 to 2.5 mm in the current data set.

[0036] The cutting size detection submodule detects the actual length data of the end of the wire harness after cutting according to the rebound error offset value, compares the difference between the target length and the measured length before and after cutting, selects the points where the error exceeds the offset threshold, and obtains the cutting length deviation; Call the rebound error offset value. In this step, the actual size after cutting is determined. The measured length of the end of the wire harness after layout needs to be called, and laser ranging is used for measurement. The data is recorded in combination with the layout point number. The measured length value in the sample is collected and the difference with the target value is calculated to form a cutting offset interval. For example, when the target length is 1200 mm, the measured values ​​are 1198.2 mm, 1197.9 mm, 1199.0 mm, 1198.6 mm, 1201.5 mm, 1197.7 mm, 1198.3 mm, and 1199.8 mm, respectively. The corresponding cutting deviations are 1.8 mm, 2.1 mm, 1.0 mm, 1.4 mm, 1.5 mm, 2.3 mm, 1.7 mm, and 0.2 mm, respectively. After taking the absolute value, judgment is made, and the points exceeding the allowable offset range of ±2.0 mm are selected as abnormal points. The offset threshold needs to be set in combination with the layout platform accuracy standard. In this embodiment, the allowable error range is set to ±2.0 mm. The setting logic is based on the standard cutting accuracy requirements of the wire harness. The range is determined by the error mean and standard deviation of multiple layout platforms in the previous error analysis and evaluation. For example, if the platform standard deviation is 0.8 mm, then 2 times the standard deviation is 1.6 mm. It is rounded up to 2.0 mm as a reasonable tolerance. The deviations of point 2 and point 6 in the table are 2.1 mm and 2.3 mm respectively, which are beyond the threshold range and should be determined as compensation trigger points as the objects of subsequent adjustment calculation. The sampled data in the table are as follows: Table 7 Cutting point measured length and deviation table: ; As shown in Table 7, the cutting deviation values ​​are mainly concentrated in the range of -2.3 mm to 1.5 mm. After combining the offset threshold judgment, the second and sixth points need to enter the compensation stage to finally form the cutting length deviation.

[0037] The compensation adjustment calculation submodule performs correction calculation based on the cutting length deviation, combined with the error direction, the start and end positions of the error section, the tension release time after cutting and other observations, using the formula: ; Calculate wire harness cut compensation adjustment ,in, Indicates The actual length after cutting at the cutting point. Indicates the target reference length of the corresponding point. Indicates the rebound trend value of the corresponding point, Indicates the duration of tension after the cutting at this point is released; According to the cutting length deviation, the cutting adjustment amount is calculated in combination with observation items such as the error direction and the duration of tension release. The error direction of the cutting point is determined by comparing the measured value with the target value. For example, if 1198.2 is less than 1200.0, it is a negative offset, which means it needs to be lengthened and adjusted. If it is 1201.5, it is a positive offset and needs to be shortened. The starting and ending positions of the error section are marked by the layout number. For example, the offset occurs at points 2 and 6, and the section is 2-6. To observe the duration of tension release, a high-speed vision module is required to record the tension fluctuation time after cutting. For example, the tension release is recorded as 0.3 seconds at point 2 and 0.2 seconds at point 6. Substitute the data into the compensation formula.

[0038] Among them, the second point data is: , , , ; The data for point 6 is: , , , , after substitution: Item 1: ; ; Item 2: ; ; Therefore, the total compensation value is: ; The result shows that the overall lengthening compensation of 4.51 mm is required. The value is rounded off and adjusted to 5.0 mm. This is used as the wire harness cutting compensation adjustment amount and input into the control system for correction control.

[0039] See also Figure 6 , the dynamic error correction module includes: The error adjustment submodule adjusts the positioning structure and cutting path of the cutting unit according to the wire harness cutting compensation adjustment amount, collects the control instruction parameters before and after the cutting unit executes, adjusts the starting coordinates and offset distance of the cutting position, matches the compensation value with the cutting reference plane position, and obtains the cutting execution adjustment value; According to the compensation adjustment amount of the wire harness cutting, the compensation value is first split into two components: position offset and direction correction. In actual operation, the compensation adjustment amount of the wire harness is processed in sections, and different starting coordinate correction values ​​are set for each section. For example, when performing correction on a wire harness with a set cutting length of 320.00 mm, according to the compensation adjustment amount of 2.30 mm given by the previous module, the starting cutting point of the cutting tool needs to be offset from the set position of 320.00 mm to 317.70 mm, and the displacement is written into the offset instruction of the cutting control system. At the same time, control parameters such as stepper motor pulse count, tool head coordinate value and guide rail correction value are recorded. Feedback data during the execution of the control system is collected in real time, such as the current position change rate of the motor, the repeated offset error of the tool starting point, etc. If the offset error exceeds 0.10 mm, the positioning adjustment is performed again, the error is sampled and the correction ratio is calculated, and the correction value is input again to complete the adjustment. Some adjustment data are given as shown in Table 8. The cutting execution adjustment value can be obtained through this series of correction operations.

[0040] Table 8 Cutting execution adjustment sample data table: ; As shown in Table 8, the second set of data has an offset error of 0.12 mm, which exceeds the re-correction threshold of 0.10 mm. Therefore, the starting point positioning needs to be corrected again. The system will add the correction amount again according to the error trend and move the starting coordinate to 296.72 mm for re-correction.

[0041] The error verification submodule detects the actual length data of the wire harness after cutting based on the cutting execution adjustment value, collects the cutting length and set size of each section of the wire harness, counts the error value and offset direction of each section, determines whether there are points that exceed the cutting error reference range, and obtains the cutting size error value; According to the cutting adjustment value, relying on the cutting result of the wire harness after the adjustment cutting instruction is completed, a laser measuring ruler is used to perform multi-point size measurement on multiple cutting segments of the wire harness, and the standard target value is set as the target length of each segment of the wire harness. For example, the target value is 320.00mm. The system will measure its final actual length with an accuracy of 0.01mm, and record the position, error direction and error value of the measuring point. The size error is then calculated based on the difference between the actual measured length of each segment and the standard value. For example, if a certain segment is measured to be 318.95mm after cutting, its error is -1.05mm, which is a negative error, indicating that it is too short. At the same time, the error location is recorded. The measurement data is shown in Table 9. After the measurement, error statistics are performed on all data, and data with a deviation greater than ±0.80mm are screened to determine whether re-compensation and correction are required, thereby obtaining the cutting size error value.

[0042] Table 9 Wire harness cutting error record table: ; As shown in Table 9, the second and third groups of cutting segments have deviations greater than ±0.80 mm, so they will be included in the step of recalculating the compensation adjustment amount. The error direction is used to determine the positive and negative polarity of the correction compensation value in the recalculation.

[0043] The compensation recalculator module selects the cutting segments with errors exceeding the range according to the cutting size error value, calculates the correction data based on the offset direction, error point location distribution, and error change amplitude, reconstructs the offset control parameters of the execution instructions of each cutting unit, and obtains the dynamic correction compensation value; According to the cutting size error value, select the segments that exceed the ±0.80mm range, extract the target length, actual length, last cutting adjustment value, error direction, cumulative offset and other data of these segments, and perform correction data calculation and processing on each segment error. For example, the deviation of the second segment is -1.05mm, and its error direction is negative, indicating that it is too short. At the same time, the previous compensation adjustment value is recorded as 2.30mm, and the cumulative offset is 2.42mm. According to the current error trend, the correction amount is increased by about 0.95mm, and the offset correction value of the control instruction is updated to 3.25mm to form new execution control data; this process will process all the segments whose cutting deviations exceed the threshold in turn, and the system will update the recalculated data of each segment by adjusting the table structure or the control list, and finally generate the dynamic correction compensation values ​​corresponding to all offset points. If the data obtained in the previous section is brought into the subsequent steps, the target length of the second section is 320.00mm, and the actual length is 318.95mm. Therefore, when calculating the new correction value, it is necessary to consider that 2.30mm has been used in the initial correction, and the current offset correction needs to be increased to 3.25mm. This value will be transmitted to the cutting execution unit later to form a new cutting instruction.

[0044] The above are only preferred embodiments of the present invention and are not intended to limit the present invention in other forms. Any technician familiar with the profession may use the technical contents disclosed above to change or modify them into equivalent embodiments with equivalent changes and apply them to other fields. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. An intelligent control system for the production process of electric wire harnesses, characterized in that: The system comprises: The path constraint analysis module collects the bending angle, curvature change, and intersection position in the wiring harness layout path, calculates the force distribution state of the wiring harness in the path, analyzes the influence of friction on the change of the wiring harness layout tension, and obtains the path force distribution; The tension balance control module analyzes the actual tension changes of the wire harness at different layout positions according to the force distribution of the path, uses the tension sensor to detect the real-time force of the wire harness, calculates the deviation between the actual tension and the force distribution of the path, dynamically adjusts the tension of the wire harness to make the tension of the wire harness uniform, and obtains the tension balance adjustment result; The instantaneous rebound determination module monitors the deformation of the wire harness at the cutting position according to the tension balance adjustment result, analyzes the instantaneous rebound of the wire harness after stretching, determines the influence of the force on the rebound trend of the wire harness, reveals the rebound characteristics of the cutting point, and obtains the rebound trend data of the wire harness; The cutting offset compensation module analyzes the size error caused by the springback of the wire harness during the cutting process according to the springback trend data of the wire harness, detects the size of the wire harness after cutting, calculates the offset of the cutting position, and obtains the cutting compensation adjustment amount of the wire harness.

2. The intelligent control system for the production process of electric wire harnesses according to claim 1 is characterized in that: The path force distribution includes the force change data at the bend, the force change data at the intersection, the friction influence area, and the tension easy change area; the tension balance adjustment result includes the real-time distribution record of tension, the tension deviation, and the tension adjustment parameters; the wire harness rebound trend data includes the rebound deformation, the rebound direction, and the rebound influence factor; the wire harness cutting compensation adjustment includes the cutting offset, the cutting error correction value, and the cutting size adjustment parameter.

3. The intelligent control system for the production process of electric wire harnesses according to claim 1 is characterized in that: The path constraint analysis module includes: The geometric feature extraction submodule obtains the spatial coordinate data of the wiring harness routing path, detects the bending angle, curvature change, and intersection position in the path, calculates the curvature radius and bending angle at each position, calculates the curvature change rate of each segment of the path based on the spatial coordinate points, identifies the three-dimensional position of the intersection, calls the curvature change rate and bending angle of the path, and obtains the path geometric feature parameters; The force state calculation submodule calculates the friction and tension distribution of each section of the path based on the path geometric characteristic parameters, calculates the ratio of friction to angle change for the bending point and intersection area, and evaluates the force characteristics of different areas of the path using the formula: ； Calculation of bending force coefficient ,in, Representative path The tension of the segment, Represents the bending angle of the path. represents the radius of curvature of this segment of the path, represents the friction coefficient of the segment, Indicates the number of path segments; The path force distribution analysis submodule combines the bending force coefficient to analyze the locations where the tension in different areas of the path is prone to change, combines the influencing factors of path friction, calculates the tension fluctuation range of each point, evaluates the sensitive areas of sudden tension changes on the path, and obtains the path force distribution.

4. The intelligent control system for the production process of electric wire harnesses according to claim 1 is characterized in that: The tension balance control module includes: The tension detection submodule obtains the force distribution of the path, monitors the real-time tension of the wire harness at different layout positions, calls the force data measured by the tension sensor, analyzes the tension state of each position, calculates the tension balance of each point, and obtains real-time tension distribution data; The tension deviation calculation submodule calculates the deviation between the actual tension at each point and the path force distribution based on the real-time tension distribution data, analyzes the tension change trend, and uses the formula: ； Calculate the relative deviation ratio of tension at each point , obtain tension deviation data, where, Representative Real-time tension of each measuring point, Represents the reference tension of the corresponding measuring point in the path force distribution, Represents the number of measuring points; The tension dynamic adjustment submodule analyzes the area where the tension of the wire harness is uneven according to the tension deviation data, calculates the tension increments that need to be adjusted in different areas, regulates the tension of the wire harness to promote tension balance, and obtains a tension balance adjustment result.

5. The intelligent control system for the production process of electric wire harnesses according to claim 1 is characterized in that: The instantaneous rebound determination module comprises: The deformation monitoring submodule monitors the length change of the wire harness at the cutting position under the force according to the tension balance adjustment result, collects the length data before stretching and at the moment of cutting, compares the deformation of each section of the wire harness, calculates the relative elongation at the cutting position, and obtains the deformation value of the cutting area; The springback analysis submodule analyzes the retraction change of the wire harness after the release of the tension based on the deformation value of the cutting area, obtains the retraction length, initial tension, release speed, and cross-sectional mass sampling data at the moment of cutting and in a short period of time after release, and compares the deformation difference and force change at different time points. The formula is used: ； Calculate the rebound response amplitude value , and analyze the rebound response intensity distribution, where Indicates the wiring harness The retraction length of each cutting point at the moment of release, Indicates The tension sampling value before the point is released. Indicates The total length change value under the point stretching state, Indicates The cross-section quality sampling value at the point cutting position, Indicates The instantaneous speed sampling value of the point tension release, Indicates the total number of cutting points; The trend data generation submodule analyzes the degree of rebound response at each point based on the rebound response amplitude value, combined with the tension change and release speed of the cutting point, determines the instantaneous rebound strength trend of the cutting area, calculates the response fluctuation amplitude of the cutting area, and obtains the wire harness rebound trend data.

6. The intelligent control system for the production process of electric wire harnesses according to claim 1 is characterized in that: The cutting offset compensation module comprises: The springback error analysis submodule extracts the instantaneous deformation variation of the cutting point according to the springback trend data of the wire harness, analyzes the cutting size error caused by the instantaneous springback, and quantifies the error offset of different points by combining the time point comparison and the deformation data variation to obtain the springback error offset value; The cutting size detection submodule detects the actual length data of the end of the wire harness after cutting according to the rebound error offset value, compares the difference between the target length and the measured length before and after cutting, selects the points where the error exceeds the offset threshold, and obtains the cutting length deviation; The compensation adjustment amount calculation submodule performs correction calculation based on the cutting length deviation, combined with the error direction, the start and end positions of the error section, the tension release time after cutting and other observations, using the formula: ； Calculate wire harness cut compensation adjustment ,in, Indicates The actual length after cutting at the cutting point. Indicates the target reference length of the corresponding point. Indicates the rebound trend value of the corresponding point, Indicates the duration of tension after the cutting at this point is released.

7. The intelligent control system for the production process of electric wire harnesses according to claim 1 is characterized in that: The system also includes a dynamic error correction module; The dynamic error correction module adjusts the cutting unit to perform error correction according to the wire harness cutting compensation adjustment amount, analyzes the size error change after cutting, counts the actual situation of the wire harness size error, and reviews the wire harness size after cutting. If there is an error, the compensation adjustment amount is recalculated for dynamic correction.

8. The intelligent control system for the production process of electric wire harnesses according to claim 7, characterized in that: The dynamic error correction module comprises: The error adjustment submodule adjusts the positioning structure and cutting path of the cutting unit according to the wire harness cutting compensation adjustment amount, collects the control instruction parameters before and after the cutting unit executes, adjusts the starting coordinates and offset distance of the cutting position, matches the compensation value with the cutting reference plane position, and obtains the cutting execution adjustment value; The error verification submodule detects the actual length data of the wire harness after cutting based on the cutting execution adjustment value, collects the cutting length and set size of each section of the wire harness, counts the error value and offset direction of each section, determines whether there is a point that exceeds the cutting error reference range, and obtains the cutting size error value; The compensation recalculator module selects the cutting segments with errors exceeding the range according to the cutting size error value, calculates the correction data based on the offset direction, error point location distribution, and error change amplitude, reconstructs the offset control parameters of the execution instructions of each cutting unit, and obtains the dynamic correction compensation value.

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