Method for calculating rolling diameter in movement

Abstract

The invention discloses a method for calculating the rolling diameter in motion, and aims to solve the problem that a certain accumulative error value exists in an existing rolling diameter calculation method. According to the technical scheme, the method is characterized by comprising the following steps that A1, encoder feedback signals are processed and optimized to be used for improving the stability of rolling diameter calculation; a2, performing filtering optimization on the calculation result of the rolling diameter in the dynamic process to obtain an optimization curve of the real-time change of the rolling diameter. According to the method, through optimization of the rolling diameter calculation method, the rolling diameter real-time waveform after optimization filtering is smoother, finer, free of up-and-down fluctuation and gradually decreased in a stepped mode compared with the prior art, and the accuracy and stability of rolling diameter calculation are improved.

Description

Technical Field

[0001] This invention relates to the field of steel coil measurement technology, and in particular to a method for calculating the diameter of a coil in motion. Background Technology

[0002] With the continuous development of industrial automation, the demand for precise measurement and control of materials such as steel coils is increasing. Especially in strip steel production lines, accurate measurement of steel coil diameter is key to achieving automatic coil loading, optimizing inventory management, and improving production efficiency.

[0003] In the prior art, patent application number CN202310156634.5 discloses a device and method for measuring the outer diameter of a steel coil. The device includes a bracket with an adjustable laser rangefinder, two cross saddles, and a trolley with two trolley rollers. The method includes the following steps: S1, the steel coil reaches the cross saddle position before the uncoiler; S2, the PLC updates the coil information; S3, the trolley rises to lift the coil to its upper limit; S4, the PLC starts calculating the outer diameter of the coil based on the laser rangefinder readings; S5, the outer diameter calculation is complete, and the next operation is performed. This invention can automatically detect the outer diameter of the steel coil, and the measured outer diameter is accurate and reliable. This invention is highly practical; by using the actual outer diameter measurement method for the steel coil, a series of problems caused by outer diameter errors during the loading process can be avoided, greatly improving operational efficiency.

[0004] However, in actual strip steel production lines, as the uncoiler uncoils the strip in the forward running direction, the current coil diameter constantly changes and gradually decreases; it is a dynamically changing value. Therefore, existing calculation methods have a certain cumulative error. This invention provides a method for calculating the coil diameter in motion to overcome the above-mentioned shortcomings. Summary of the Invention

[0005] The purpose of this invention is to provide a method for calculating the diameter of a roll in motion, which solves the problem of accumulated error values ​​in existing roll diameter calculation methods.

[0006] The above-mentioned technical objective of this invention has been achieved by the following technical solutions:

[0007] A method for calculating the diameter of a moving object includes the following steps:

[0008] A1: Optimization of encoder feedback signal processing to improve the stability of roll diameter calculation;

[0009] A2: Filtering and optimization of the dynamic process roll diameter calculation results to obtain an optimized curve for real-time roll diameter changes.

[0010] The encoder feedback signal processing optimization in step A1 includes the following steps:

[0011] B1: Introduce the coefficient variable MSL_REV;

[0012] B2: When ΔP A ≥P A At that time, the output flag signal MSL_CAL is activated, and ΔP is set to... A / P A The arithmetic result is assigned to the coefficient variable MSL_REV;

[0013] B3: Using the obtained MSL_REV, calculate the more accurate change in the sampling period ΔP during each data refresh cycle. A and ΔP B .

[0014] In step B3, the de facto zeroing ΔP A and ΔP B The arithmetic formula is as follows:

[0015] (MSL_REV-1)×P A =ΔP A '(1)

[0016]

[0017] The formula for filtering optimization of the dynamic process roll diameter calculation result in step A2 is as follows:

[0018]

[0019] The derivation of the above formula includes the following steps:

[0020] C1: The final calculated roll diameter after filtering is denoted as F. A (n'), where the subscript A represents the actual value;

[0021] C2: Add intermediate variable F O (n'), where the subscript O represents the old value from the previous scan cycle;

[0022] C3: Add a new variable ΔF(n'), which represents the difference in roll diameter before and after the program scanning cycle when the uncoiler rotates for the nth time. The relationship is as follows:

[0023] F(n')≠F A (n')(4)

[0024] F O (n')>F A (n')(5)

[0025] F(n')-FA (n')=ΔF(n')(6)

[0026] When the unit is not in operation, ΔF(n') is zero; the current coil diameter at the nth rotation of the uncoiler is represented as d-2tn'; substituting ΔF(n') into the equation, the following relationship is obtained:

[0027] ΔF(n')-2tn',n'=1(7)

[0028] ΔF(1)-2t

[0029] Formula 7 represents the change in roll diameter before and after each program scanning cycle of the uncoiler. To represent this change, it needs to be multiplied by a dynamic variation coefficient n, i.e., n” = ΔP A / P A Then, the old value F temporarily stored in the previous program scan cycle is added to it through the adder. O (n'), to obtain the final filtered convolutional diameter value and thus F. A (n').

[0030] In summary, the present invention has the following beneficial effects:

[0031] This method optimizes the roll diameter calculation method, resulting in a smoother, more refined real-time waveform of the filtered roll diameter that is free from fluctuations and gradually decreases in a step-like manner. This method improves the accuracy and stability of roll diameter calculation. Attached Figure Description

[0032] Figure 1 This is a simplified logic flowchart of the present invention.

[0033] Figure 2 This is a schematic diagram of the ideal master-slave roller positions of the present invention. Detailed Implementation

[0034] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to the figures and specific embodiments.

[0035] like Figure 2 As shown, in existing methods for calculating coil diameter, the initial coil diameter of the uncoiler is automatically calculated by measuring the inlet height during coil loading. Ideally, there is no relative slippage between the reference roll and the strip. During normal production operation at the same linear speed, the trajectory lengths of one revolution made by point A on the uncoiler and point B on the reference roll are equal.

[0036] Assuming that roller A has a diameter of 500mm and roller B also has a diameter of 500mm, according to the circumference formula, we can obtain:

[0037] C1=πd1=πd2=C2

[0038] Where C1 represents the circumference of point A's movement around roller A, d1 represents the diameter of roller A, C2 represents the circumference of point B's movement around roller B, and d2 represents the diameter of roller B. If the rollers rotate n times, then:

[0039] n1C1=n1πd1=n2πd2=n2C2

[0040] Since rollers A and B have the same diameter, n1 = n2.

[0041] The existing roll diameter calculation method has the following problems: The initial roll diameter of the existing uncoiler is automatically calculated by measuring the height at the inlet when the roll is loaded. The calculated initial value is assigned to F(n') in the program. At this time, F(n') is the initial roll diameter value for the first time. The calculated data has a deviation from the actual value, and F(n') needs to be corrected.

[0042] The scanning cycle is executed by the PLC program. In this embodiment, the scanning cycle is set to 50ms. f(n')-F(n') is the Δ change in data before and after the program scanning cycle. After LIMIT limiting, the final current unwinding machine roll diameter value F(n') after real-time data correction is obtained through the adder, thereby improving the calculation accuracy.

[0043] The core formula for calculating the diameter of steel coils using existing uncoilers is:

[0044]

[0045] Where, ΔP B / P B =n2, ΔP B This indicates the cumulative change fed back by the main pinch roller encoder within the PLC program sampling period; P B The code value representing the encoder's value for one revolution of the main pinch roller is equal to the number of pulses in one revolution of the encoder multiplied by the gear ratio of the corresponding motor; ΔP A / P A =n”, ΔP A This represents the cumulative change in feedback from the uncoiler encoder within the PLC program sampling period; P A The dimension of the encoder code value for one revolution of the uncoiler is equal to the number of pulses in one revolution of the encoder multiplied by the gear ratio of the corresponding motor; after each revolution of the uncoiler, the sampling period ΔP is reset to zero. A and ΔP B The change amount is calculated, and the current volume diameter of f(n') is refreshed at the same time.

[0046] In actual strip steel production lines, as the uncoiler uncoils the strip in the forward direction, the current coil diameter constantly changes and gradually decreases; it is a dynamic value. Therefore, existing calculation methods have a certain cumulative error.

[0047] The cumulative feedback change ΔP of the existing uncoiler encoder A After the encoder code value reaches the dimension of one revolution of the uncoiler, that is, when ΔP A ≥P A At the same time, output a flag signal "MSL_CAL" and clear the change ΔP to zero. A and ΔP B ;

[0048] During high-speed operation of the production line, ΔP A and ΔP B Signal disturbances cause numerical deviations, and existing calculation methods directly reset the change ΔP to zero. A and ΔP B This will lead to some ΔP A and ΔP B The value was missed, which led to fluctuations in the roll diameter.

[0049] To solve the above problems, such as Figure 1 As shown, the present invention proposes a method for calculating the diameter of a moving object, which includes the following steps:

[0050] A1: Optimization of encoder feedback signal processing to improve the stability of roll diameter calculation;

[0051] A2: Filtering and optimization of the dynamic process roll diameter calculation results to obtain an optimized curve for real-time roll diameter changes.

[0052] The encoder feedback signal processing optimization in step A1 includes the following steps;

[0053] B1: Introduce the coefficient variable MSL_REV;

[0054] B2: When ΔP A ≥P A At that time, the output flag signal MSL_CAL is activated, and ΔP is set to... A / P A The arithmetic result is assigned to the coefficient variable MSL_REV;

[0055] B3: Using the obtained MSL_REV, calculate the more accurate change in the sampling period ΔP during each data refresh cycle. A and ΔP B ;

[0056] Among them, the disguised zeroing ΔPA and ΔP B The arithmetic formula is as follows:

[0057] (MSL_REV-1)×P A =ΔP A '

[0058]

[0059] ΔP after de facto zeroing A and ΔP B Using ΔP respectively A 'and ΔP B This indicates that, compared to existing calculation methods, the change ΔP will be... A and ΔP B The value is assigned to MSL_REV, but not cleared to zero. Furthermore, the value of the coefficient variable MSL_REV is close to 1. This allows for the calculation of a more accurate change in the sampling period, ΔP, during each data refresh cycle. A and ΔP B .

[0060] The formula for filtering optimization of the dynamic process roll diameter calculation result in step A2 is as follows:

[0061]

[0062] The derivation of the above formula is as follows:

[0063] C1: The final calculated roll diameter after filtering is denoted as F. A (n'), where the subscript A represents the actual value;

[0064] C2: Add intermediate variable F O (n'), where the subscript O represents the old value from the previous scan cycle;

[0065] C3: Add a new variable ΔF(n'), where ΔF(n') represents the difference in roll diameter before and after the program scanning cycle when the uncoiler rotates for the nth time. The PLC program scans and executes the code in a pre-written sequence, from top to bottom and from left to right, with a time interval of 50mm. The relationship is as follows:

[0066] F(n')≠F A (n')

[0067] F O (n')>F A (n')

[0068] F(n')-F A (n')=ΔF(n')

[0069] The flag signal CALIL is for unit operation interlocking. When the unit is not in operation, the constant is assigned to "zero" at ΔF(n') to clear the data.

[0070] d-2tn' represents the current coil diameter value when the uncoiler rotates for the nth revolution, which is the dynamic value of the uncoiler.

[0071] ΔF(n')-2tn', n'=16

[0072] ΔF(1)-2t

[0073] By changing the diameter, substituting ΔF(n') into the equation, we get the result.

[0074] The above formula represents the change in roll diameter difference before and after the program scanning cycle at each revolution of the uncoiler, i.e., between two adjacent revolutions. To dynamically reflect the change in a decreasing or increasing manner, it needs to be multiplied by a dynamic change coefficient n, i.e., n” = ΔP A / P A This represents the percentage of any single revolution at the tangent point A of the uncoiler. Then, the old value F temporarily stored in the previous program scan cycle is added to it via an adder. O (n'), to obtain the final filtered convolutional diameter value and thus F. A (n'), that is:

[0075]

[0076]

[0077] Pin function definition diagram

[0078] This method optimizes the roll diameter calculation, resulting in a smoother, more refined real-time waveform with no vertical fluctuations and a gradual, step-like decrease in roll diameter after filtering. Field testing results demonstrate that the new method improves the accuracy and stability of roll diameter calculation, making the timing of automatic deceleration and automatic stopping at the tail end of the strip more accurate. In actual operation, the strip's vibration is more stable compared to before optimization.

[0079] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "left," and "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. These terms are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance. In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, terms such as "set" and "connect" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances. In this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, which includes not only the elements listed but also other elements not expressly listed.

[0080] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for calculating the diameter of a moving object, characterized in that, Includes the following steps: A1: Optimization of encoder feedback signal processing to improve the stability of roll diameter calculation; A2: Filtering and optimization of the dynamic process roll diameter calculation results to obtain an optimized curve for real-time roll diameter changes.

2. The method for calculating the diameter of a moving object according to claim 1, characterized in that, The encoder feedback signal processing optimization in step A1 includes the following steps: B1: Introduce the coefficient variable MSL_REV; B2: When ΔP A ≥P A At that time, the output flag signal MSL_CAL is activated, and ΔP is set to... A / P A The arithmetic result is assigned to the coefficient variable MSL_REV; B3: Using the obtained MSL_REV, calculate the more accurate change in the sampling period ΔP during each data refresh cycle. A and ΔP B . In step B3, the de facto zeroing ΔP A and ΔP B The arithmetic formula is as follows: (MSL_REV-1)×P A =ΔP A ' (1) 3. The method for calculating the diameter of a roll in motion according to claim 1, characterized in that, The formula for filtering optimization of the dynamic process roll diameter calculation result in step A2 is as follows: The derivation of the above formula includes the following steps: C1: The final calculated roll diameter after filtering is denoted as F. A (n'), where the subscript A represents the actual value; C2: Add intermediate variable F O (n'), where the subscript O represents the old value from the previous scan cycle; C3: Add a new variable ΔF(n'), which represents the difference in roll diameter before and after the program scanning cycle when the uncoiler rotates for the nth time. The relationship is as follows: F(n')≠F A (n') (4) F O (n')>F A (n') (5) F(n')-F A (n')=ΔF(n') (6) When the unit is not in operation, ΔF(n') is zero; the current coil diameter at the nth revolution of the uncoiler is represented as d-2tn'; substituting ΔF(n') into the equation, the following relationship is obtained: ΔF(n')-2tn',n'=1 (7) ΔF(1)-2t Formula 7 represents the change in roll diameter before and after each program scanning cycle of the uncoiler. To represent this change, it needs to be multiplied by a dynamic variation coefficient n, i.e., n” = ΔP A / P A Then, the old value F temporarily stored in the previous program scan cycle is added to it through the adder. O (n'), to obtain the final filtered convolutional diameter value and thus F. A (n').

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