Ship plate processing equipment control method and system

Abstract

The invention relates to the technical field of equipment processing, in particular to a ship board processing equipment control method and system.The method comprises the steps that the fiber rolling direction of a board to be processed is detected, and an initial processing track is generated in combination with a target contour; inputting the initial processing track into a fiber-track coupling model, and outputting a notch quality prediction parameter; and optimizing an initial processing track according to the cut quality prediction parameters, generating a tear-resistant processing track and controlling an execution mechanism to operate. According to the method, on the basis of coupling of material mechanical properties and machining dynamics, the prediction precision and the local response identification capability are remarkably improved, the notch quality defect caused by small-angle cutting, excessive curvature or vibration excitation is effectively avoided, a scientific basis is provided for trajectory optimization, and the method is suitable for large-scale popularization and application. And the stability and the flexible control capability in the machining process are improved, the cleanliness and the structural integrity of a final plate notch are remarkably improved, and the good industrial application value and the good popularization prospect are achieved.

Description

Technical Field

[0001] This invention relates to the field of equipment processing technology, and in particular to a control method and system for ship plate processing equipment. Background Technology

[0002] In the shipbuilding industry, with the widespread application of high-strength, large-size plates, higher requirements have been placed on the quality and stability of the plate cutting process. Traditional processing equipment often relies on preset trajectories for plate cutting, ignoring the influence of the rolling fiber direction on the cut quality, which can easily induce defects such as tearing, burrs, or fiber breakage during processing. In addition, due to the anisotropic fiber orientation formed during the rolling process, the mechanical response of different parts is significantly different, resulting in uneven quality and a decrease in the finished product qualification rate under fixed trajectory processing. Especially in complex contours or critical curvature areas, it is difficult to balance processing accuracy and structural integrity.

[0003] Existing control systems are mostly general-purpose path control systems, lacking intelligent control mechanisms that are deeply integrated with the microscopic properties of materials. They cannot effectively predict cut quality or implement dynamic intervention in high-risk areas. Especially when facing areas with high tear risk, the lack of flexible compensation and energy self-adaptation mechanisms leads to the superposition of processing errors and increased equipment wear, which seriously restricts the manufacturing efficiency and quality consistency of high-performance hull structures. Therefore, it is urgent to build an intelligent processing system that integrates material fiber response, tear risk prediction, and trajectory adaptive control to achieve deep synergy between cutting path and microstructural behavior, thereby improving the processing quality and process safety of ship plates. Summary of the Invention

[0004] To achieve the above objectives, the present invention provides a control method and system for ship plate processing equipment.

[0005] A method for controlling ship plate processing equipment includes the following steps:

[0006] S1: Detect the rolling fiber direction of the sheet material to be processed and generate an initial processing trajectory based on the target contour;

[0007] S2: Input the initial processing trajectory into the fiber-trajectory coupling model and output the cut quality prediction parameters;

[0008] S3: Optimize the initial processing trajectory based on the cut quality prediction parameters, generate an anti-tear processing trajectory, and control the operation of the actuator.

[0009] Furthermore, S1 includes:

[0010] S11, Detection of rolled fiber direction: The surface of the board is scanned by an eddy current sensor, and the overall fiber flow angle of the board is calculated based on the difference in conductivity in different directions.

[0011] S12, Fiber reliability verification: The aspect ratio of the grains is analyzed by metallographic image sampling and compared with the eddy current detection results to determine whether there is a clear fiber flow direction and to verify the reliability of the orientation angle.

[0012] S13, Initial processing trajectory generation: Combine the target contour point set with the detected fiber direction to construct the initial processing trajectory;

[0013] S14, Trajectory Smoothing Processing: The initial trajectory is optimized, taking into account the smoothness of the path curvature and the tear resistance direction angle requirements. The position of the trajectory points is adjusted on the premise that the processing error does not exceed the maximum allowable error threshold of the trajectory offset.

[0014] Furthermore, S13 includes:

[0015] S131, Contour point set construction and orientation information fusion: After obtaining the overall fiber flow angle of the board, extract the contour point set of the target processing area;

[0016] S132, Trajectory Weight Function Calculation and Initial Path Generation: Based on the angle relationship between the geometric contour and the fiber direction, a trajectory weighting function that comprehensively considers processing accuracy and tear resistance is constructed. The trajectory optimization weight is calculated segment by segment to generate an initial processing trajectory with directional protection capability.

[0017] Furthermore, S14 includes:

[0018] S141, Curvature and orientation constraint optimization modeling: Under the premise of keeping the trajectory points close to the original contour, an optimization model that comprehensively considers the smoothness of trajectory curvature and fiber orientation protection is constructed. The path segments that deviate from the optimal orientation angle are restricted by the penalty term, and the curvature change between trajectory points is controlled.

[0019] S142, Trajectory point position update and error limit: Optimize and adjust the initial trajectory points to generate a new trajectory point sequence.

[0020] Furthermore, S2 includes:

[0021] S21, Trajectory Discretization Processing: The initial processing trajectory is subdivided according to the directional change trend and curvature feature points to generate multiple trajectory micro-segments. The length of each micro-segment is set according to the minimum value of the angle between the radius of curvature and the fiber direction.

[0022] S22, Cutting state calculation: Based on the trajectory micro-segment, a cutting dynamics response model is constructed to calculate the main cutting force and the radial vibration force caused by fiber resonance respectively;

[0023] S23, Cut quality parameter prediction: Based on the calculated cutting force results, predict three cut quality indicators for each micro-segment, including burr height gradient, microcrack density and fiber tear index.

[0024] S24, Parameter Space Mapping: The cut quality prediction parameters of the micro-segment are weighted by a Gaussian kernel function and mapped to the continuous trajectory coordinate system to obtain a continuous cut quality prediction vector that varies with position.

[0025] Furthermore, S23 includes:

[0026] S231, Burr height gradient calculation: Calculate the burr height gradient based on the degree of non-uniform deformation of the edge under the action of cutting force;

[0027] S232, Microcrack density prediction: Calculate the microcrack density by combining the fiber attenuation effect caused by the angle factor and the change rate of the main cutting force;

[0028] S233, Fiber tear index estimation: The fiber tear index is calculated by using an S-shaped function to express the abrupt behavior of tear damage after exceeding the tear critical force threshold.

[0029] Furthermore, S24 includes:

[0030] S241, Trajectory Coordinate System Parameter Projection: Mapping the cut quality parameters obtained for each trajectory micro-segment to the corresponding position points in the trajectory coordinate system;

[0031] S242, Gaussian weighted smooth fusion: The quality parameter values ​​of each mapped cut are weighted and superimposed using a Gaussian kernel function.

[0032] Furthermore, S3 includes:

[0033] S31, Trajectory Optimization Modeling: Construct a dual-objective optimization model that comprehensively considers geometric contour deviation and fiber tear index. Through trajectory point offset and integral risk control, the optimal processing path is achieved, while setting constraints on included angle, curvature and burr height.

[0034] S32, Laser-Assisted Softening Integration: For trajectory segments with a high risk of tearing, a laser softening operation is introduced, and the laser power and scanning speed are dynamically calculated based on the degree of exceeding the tear index.

[0035] S33, Flutter Compensation Generation: When the crack density exceeds the critical threshold of crack density, the normal compensation strategy is activated to generate an attenuated sinusoidal displacement signal based on the fiber vibration frequency and crack density information.

[0036] S34, Actuator Cooperative Control: Transforms optimized trajectory and laser processing information into equipment control commands.

[0037] Furthermore, S31 includes:

[0038] S311, Establish a dual-objective optimization function: Construct a dual-objective optimization model that includes a geometric deviation term and a tearing index integral term, and coordinate the importance of the two objectives through weighting coefficients;

[0039] S312, Set multiple constraints: Introduce three processing stability constraints.

[0040] A control system for ship plate processing equipment, used to implement the above-mentioned control method for ship plate processing equipment, includes the following modules:

[0041] Fiber orientation detection and trajectory initialization module: detects the main orientation of the rolled fibers of the ship plate to be processed, combines it with the preset target contour information, generates the initial processing trajectory and performs standardized coding;

[0042] Fiber-trajectory coupling quality prediction module: Input the initial processing trajectory into the constructed fiber-trajectory coupling model, input variables based on the board properties, fiber direction and trajectory geometric parameters, and output a set of cut quality prediction parameters that reflect tear risk and defect trend;

[0043] The trajectory optimization and execution control module optimizes the initial trajectory based on the cut quality prediction parameters, constructs a multi-objective optimization path by combining geometric accuracy and tear sensitivity, and converts the final tear-resistant processing trajectory into control commands to drive the actuator to complete the processing task.

[0044] The beneficial effects of this invention are:

[0045] This invention introduces a fiber-trajectory coupling model, which for the first time dynamically correlates the rolling fiber direction of the sheet metal with the processing path, enabling feedforward prediction of quality parameters such as tear risk, burr height, and crack density. Compared with traditional empirical path control methods, this model is based on the coupling of material mechanical properties and processing dynamics, significantly improving prediction accuracy and local response identification capabilities. It effectively avoids cut quality defects caused by small-angle cutting, excessive curvature, or vibration excitation, providing a scientific basis for trajectory optimization.

[0046] This invention constructs a three-level closed-loop mechanism that includes laser softening, chatter compensation, and motion coordinated control. This mechanism enables adaptive adjustment of the trajectory driven by quality prediction and linkage with processing strategies. It can proactively insert laser preheating and adjust the spindle speed and feed rate for high-risk areas, ensuring smooth stress release and controlled crack propagation during processing. This not only improves the stability and flexibility of the processing but also significantly enhances the cleanliness and structural integrity of the final sheet metal cut, demonstrating good industrial application value and promising prospects for promotion. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a flowchart of a method according to an embodiment of the present invention;

[0049] Figure 2 This is a system block diagram of an embodiment of the present invention. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0051] It should be noted that, unless otherwise defined, the technical or scientific terms used in this invention should have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0052] like Figure 1 As shown, a control method for ship plate processing equipment includes the following steps:

[0053] S1: Detect the rolling fiber direction of the sheet material to be processed and generate an initial processing trajectory based on the target contour;

[0054] S1 specifically includes:

[0055] S11, Fiber Direction Detection in Rolled Sheets: Eddy current scanning is performed on the processed sheet material. Based on the difference in conductivity in different directions, the dominant direction angle of the rolled fibers is extracted using phase difference analysis. A ratio function of the orthogonal eddy current induced voltage gradient is constructed, and the average is calculated over all detection points to calculate the overall fiber flow direction angle θ of the sheet material, expressed as:

[0056]

[0057] Where θ represents the fiber orientation angle of the rolled sheet in degrees, and n represents the number of detection points, with a value range of n≥36. A 6×6 grid is used for uniform distribution, and the number of detection points n is set to be no less than 36. This is mainly to cover possible anisotropic variations within the sheet area while ensuring spatial resolution. Using a 6×6 uniform grid helps improve detection uniformity and angular average accuracy, and avoids local disturbances affecting the overall judgment. These represent the eddy current induced voltage gradients at the r-th detection point in the x and y directions, respectively, with units of mV / mm. They reflect the trend of conductivity change in the orthogonal directions and are derived from the induced changes of the eddy current sensor between small displacements.

[0058] S12, Fiber Reliability Verification: To enhance the accuracy of fiber orientation measurement, cross-validation of the detection area is performed using micro-area metallography. By sampling the detection area using micro-area metallography, the grain aspect ratio ρ is obtained to verify the reliability of the detected fiber orientation angle, expressed as:

[0059] And |θ-θ 金相 |≤δ θ ;

[0060] Here, ρ represents the grain aspect ratio. When ρ > 2.5, it is considered that there is a significant fiber flow direction. This setting is based on the statistical laws of the microstructure of rolled materials such as marine steel and high-strength steel. In a typical rolling process, the material undergoes plastic elongation in the rolling direction, and its grain structure exhibits an elliptical stretched state. When the aspect ratio exceeds 2.5, the grains are significantly elongated, reflecting a strong texture directionality. That is, the macroscopic rolling fiber direction has been strengthened by the microscopic grain orientation consistency. Therefore, 2.5 is a widely used criterion for judging the significance of fiber structure. The empirical lower bound for reliability, where m represents the number of metallographic sampling points, has a value range of m≥5, reflecting the balance between statistical reliability and detection cost. Metallographic image processing involves high-resolution imaging under microscopic fields of view. Insufficient sampling makes it susceptible to local structural anomalies, while excessive sampling significantly increases detection time and labor costs. In relatively homogeneous rolled plates, selecting at least 5 fields of view and extracting 12 typical grain data in each field of view can obtain relatively stable directional features. Therefore, m≥5 is the minimum sample size standard to meet the accuracy requirements of engineering applications. j W j θ represents the length and width of the j-th grain, respectively, in μm. 金相 δ represents the reference fiber orientation angle obtained from metallographic analysis. θ δ is the directional deviation tolerance threshold parameter, used to determine whether the eddy current testing results are consistent with the metallographic direction. θ=3°, the value of which is 3° comprehensively considers the multi-source error factors in the angle measurement process of the eddy current detection system and metallographic analysis method. Specifically, the eddy current phase difference method has an orientation angle resolution of about ±1.5° under typical ship plate materials and commonly used excitation frequencies (such as 100-300kHz). However, the principal axis fitting in metallographic images is affected by the microscopic image resolution, threshold segmentation error, and grain irregularity, and its extraction angle error is also about ±1°-1.5°. After combining the errors of the two, the total deviation may reach about ±2.5°. Set δ θ =3° as the upper limit of tolerance can effectively cover the range of conventional detection errors while retaining a certain redundancy, ensuring a balance between the reliability of judgment and the robustness of engineering. It is a reasonable choice that takes into account both accuracy constraints and practical operability.

[0061] S13, Initial processing trajectory generation: After obtaining the fiber direction angle θ of the sheet rolling, combine the geometric point set P = {p1, p2, ..., p...} of the target processing contour. k} An initial processing trajectory for tear resistance is constructed, and a weighted approach is used to balance geometric approximation and directional tear resistance. The optimization weight value for each trajectory segment is defined as follows:

[0062]

[0063] Where k is the total number of contour points in the geometric point set of the processed contour, i.e., the number of trajectory segments, and s i This represents the optimized weight value of the i-th trajectory segment. β represents the Euclidean distance between adjacent contour points, ranging from 0.5 to 5. This value is based on the typical machining accuracy of laser cutting or CNC milling heads, ensuring trajectory continuity while avoiding redundant commands and equipment response delays caused by redundant path points. i γ is the angle between the trajectory tangent direction and the plate rolling direction, ranging from [0°, 90°]. It represents the cutting direction relationship from completely parallel to completely perpendicular. Different angles have a significant impact on the tearing tendency of the cutting edge, especially when the angle is close to 45°, the tearing risk is minimal, making it an important target variable for optimizing crack resistance. i This represents the deviation angle between the trajectory direction and the fiber direction. The value range is [0°, 90°], γ i The deviation angle characterizes the directional difference between the trajectory direction and the material fiber structure direction. Its physical essence is an absolute angle difference. In path optimization, the deviation angle is used to evaluate the synergy of the material structure direction. Controlling it to be close to 45° is an important step in improving tear resistance. α is a geometric accuracy weighting factor, with a value range of [0.7, 0.9]. For high-strength, directionally sensitive steels, a higher weight should be given to the tear resistance direction. Therefore, the value of α increases with the material grade to enhance responsiveness to fiber direction. This represents the tangential direction angle of the trajectory. This angle indicates the absolute direction of the tangent line of the trajectory, defined in a two-dimensional plane, and its value ranges from [0°, 90°]. The tangential direction angle of the trajectory is used in the comparison of fiber directions and is a fundamental variable for calculating the deviation angle and the included angle, ensuring the symmetry and completeness of the direction information. The initial processing trajectory for constructing tear resistance characteristics is formed by the point set P = {p1, p2, ..., p...} k The trajectory segments are sequentially connected and weighted using an optimized weighting function to guide subsequent smoothing processes.

[0064] S14, Trajectory Smoothing Processing: To improve trajectory continuity and tear resistance, while ensuring that processing errors do not exceed limits, the initial trajectory point sequence {p} is smoothed. i The optimized point sequence {q} is obtained by applying a constraint optimization algorithm based on curvature and fiber protection. i The optimization model is expressed as:

[0065]

[0066] Where, k i This represents the trajectory curvature of the i-th detection point, in meters. -1 λ reflects the local curvature of the trajectory point. Minimizing this value helps avoid overly sharp or volatile trajectories, maintaining the continuity of tool movement and the stability of the machined surface. λ represents the fiber protection penalty factor, ranging from [10, 50], which is adjusted based on the differences in material fracture toughness. For brittle materials, such as high-strength steel or ultra-thin plates, a larger penalty weight should be given to avoid excessive deviation between the path direction and the fiber direction, leading to tearing. For materials with higher toughness, λ can be appropriately reduced. 40° is the deviation from the optimal direction angle, which is the confirmed optimal direction angle for tear resistance and has wide applicability. max This represents the maximum permissible error threshold for trajectory offset, in mm, with a default value of 0.1 mm. It is a recognized upper limit for acceptable contour deviation in industrial-grade cutting, maintaining assembly accuracy while allowing for a certain degree of optimization freedom. This balances shape fidelity and structural protection. The overall parameter settings emphasize global optimization of the tear-resistant trajectory under precision constraints. i Let be the coordinates of the i-th optimized trajectory point.

[0067] S2: Input the initial processing trajectory into the fiber-trajectory coupling model and output the cut quality prediction parameters;

[0068] S2 specifically includes:

[0069] S21, Trajectory Discretization: To more precisely capture directional changes and local curvature features in the processing path, the initial processing trajectory is discretized according to the geometric change trend. The initial processing trajectory is segmented according to curvature feature points, resulting in m' trajectory micro-segments. Based on the radius of curvature and fiber direction angle of each segment, a reasonable length for each micro-segment is determined. This length should balance the analytical capability of geometric changes with the stability of physical processing; therefore, the smaller of the two is taken, expressed as:

[0070]

[0071] Among them, L l R is the length of the l-th micro-segment, in mm. This length setting ensures higher resolution mechanical modeling in regions with small curvature or small included angles. l γ is the radius of curvature of the l-th micro-segment, ranging from 5 to 500 in mm; T is the thickness of the sheet metal, ranging from 6 to 25 in mm; γ l is the angle between the tangential direction of the l-th micro-segment trajectory and the fiber direction, with a value range of [0°, 90°]. m' is the total number of trajectory micro-segments generated after discretization. 0.2 is the "geometric control term" in trajectory discretization, indicating that each micro-segment can cover a maximum of 20% of the radius of curvature. This ratio is a common empirical coefficient used for curve segmentation in engineering modeling. Setting it to 0.2 ensures that there is no over-segmentation when the curvature is large (the path is relatively straight), while automatically refining the discretization density at small radii of curvature, improving the analytical accuracy of the mechanical model for curved sections, and avoiding the accumulation of physical modeling errors. This is the "structural orientation control term," reflecting the influence of material thickness and the tangential angle on the spatial resolution of the cutting force model. The smaller the angle (i.e., closer to parallel to the cutting fiber direction), the easier it is for tearing to occur. Therefore, it is necessary to refine the trajectory micro-segments in this region to enhance modeling accuracy. This term is determined by sinγ. l Reducing the length of micro-segments automatically shortens high-risk sections, ensuring the stability of cutting modeling;

[0072] S22, Cutting State Calculation: Based on the obtained trajectory micro-segments, a cutting dynamics response model is established for each segment to calculate the main cutting force and the radial vibration force caused by fiber resonance during machining. The main cutting force model considers the influence of material mechanical properties, feed parameters, and fiber direction on cutting resistance. A resonance function with a time term is then introduced to simulate the periodic load fluctuations caused by the coupling between the feed process and the material fiber structure, thus obtaining the radial vibration force. The cutting dynamics state of each micro-segment is solved, and the main cutting force F... t and radial vibration force F r , represented as:

[0073]

[0074] Among them, F t It is the main cutting force, used to represent the main resistance of the tool along the feed direction, and its unit is N, F. r It is radial vibration force, representing the periodic disturbance load caused by fiber resonance, and is measured in N or K. c It is the material's cutting coefficient, reflecting the cutting force required per unit area. For EH36 steel, the value ranges from 210 to 240 N / mm². 2 It can cover changes in processing stress and adapt to engineering safety margins. p 1. Cutting depth: The vertical depth to which the tool cuts into the material in one pass. Its value ranges from 0.5 to 2.0 mm, balancing machining efficiency and edge integrity. Too deep a cut can lead to tearing, while too shallow a cut results in low efficiency. 2. Feed rate: The length of material advanced by the tool per revolution. It directly affects cutting efficiency and stability. Its unit is mm / r. 3. Feed rate exponent: Describes the nonlinear effect of the feed rate on the cutting force. Its value ranges from 0.78 to 0.85, effectively reflecting the actual mechanical response. 4. Fiber orientation sensitivity factor: Controls the weight of the orientation angle on the attenuation of the cutting force. Its value ranges from 0.02 to 0.03, ensuring sensitivity to the included angle while avoiding excessive attenuation. 5. Vibration transmissibility: Its value ranges from 0.15 to 0.25, effectively reflecting the amplification of disturbances during structural resonance. c This is the fiber resonant frequency, the natural frequency of the fiber structure under load, which affects the vibration wave period and is crucial for tear sensitivity simulation. The unit is Hz, and t is the time variable, with the unit being seconds. This is the phase offset, used to describe the initial vibration phase, with a value range of 0-360°, which helps to establish the integrity of the time-domain perturbation model;

[0075] S23, Cut Quality Parameter Prediction: Based on the obtained mechanical response results, the cut quality of each trajectory micro-segment is evaluated using multi-dimensional indicators, including geometric surface integrity, structural damage sensitivity, and potential tear risk. Specifically, this includes:

[0076] (1) Burr height gradient H b : Used to measure the degree of non-uniform deformation at the cutting edge, it depends on the ratio of radial vibration force to the main cutting force and the angle between their directions, and is expressed as:

[0077]

[0078] Among them, H b α is the burr height gradient, which measures the degree of non-uniform deformation of the cutting edge, in μm / mm. α' is the burr formation factor, which adjusts the influence of vibration amplitude and direction on burrs. Its value ranges from 0.12 to 0.18, which can match the influence of vibration feedback on edge micro-deformation in marine steel plate processing, ensuring that the model is sensitive to local roughness and does not overfit.

[0079] (2) Microcrack density ρ c The crack formation trend is reflected by the nonlinear attenuation term of the angle factor and the rate of change of cutting force, and is expressed as:

[0080]

[0081] Where, ρ c β' is the microcrack density, expressed in lines / mm. β' is the crack sensitivity coefficient, representing the material's sensitivity to microcrack formation during processing. Its value ranges from 1.5 to 2.2. The material's susceptibility to cracks is affected by the uniformity of the microstructure and stress distribution. Setting the value to 1.5-2.2 can effectively reflect the amplification effect of microcracks in stress concentration areas in medium and high strength steel. k' is the angle attenuation constant, which controls the intensity of the influence of the included angle on crack formation. Its value ranges from 0.05 to 0.08. It can achieve a significant strengthening response in the included angle range of less than 30°, while being sensitive to attenuation at large angles to prevent overestimation of risk.

[0082] (3) Fiber tearing index ε: The probability of abrupt change in tear damage after reaching the critical force is expressed by a sigmoid function as follows:

[0083]

[0084] Where ε is the fiber tearing index, a dimensionless parameter ranging from [0,1], c' is the tear growth coefficient, used to adjust the steepness of the transition from "no" to "abrupt" tear risk, ranging from 0.25 to 0.35, which can accurately simulate the "critical transition" in the actual tearing process, that is, the phenomenon of a sharp increase in tear probability when the disturbance force exceeds the threshold, F th The tearing critical force threshold is a critical load used to describe the critical load at which a material reaches rapid microcrack propagation or fiber breakage under loading in a specific direction. Its setting is related to the material's fracture toughness, local thickness, fiber structure orientation, and the mode of load application. The value ranges from 80 to 150, and the unit is N. This range can reflect the crack initiation susceptibility of the material under low-angle cutting (i.e., the direction is close to parallel to the fibers) while retaining a certain safety margin to prevent premature entry into the tearing judgment region. It is the time derivative of the main cutting force, representing the rate of change of load. It can reflect the sensitivity of micro-damage induced by dynamic load and is an important variable in crack risk modeling.

[0085] S24, Parameter Space Mapping: To achieve continuous quality prediction results at the trajectory level, the cut quality parameters calculated from each of the aforementioned micro-segments are mapped to the trajectory coordinate system. A Gaussian kernel function is used to weight and superimpose the results of each micro-segment to form a continuous trajectory quality prediction vector, achieving a smooth transition from discrete points to continuous prediction values ​​in space, expressed as:

[0086]

[0087] Where Ψ(s) is the cut quality prediction vector at trajectory coordinate s. It is the burr height gradient of the l-th micro-segment. It is the microcrack density of the l-th micro segment, ε (l) It is the fiber tear index of the l-th micro-segment, with a value range of [0,1], s l It is the position of the center point of the l-th micro-segment in the arc-length coordinate system, and σ is the Gaussian smoothing radius, set as v = L. l / 3, σ∈[0.2,2], can ensure that each trajectory point is mainly affected by about 1-2 micro-segments before and after it during the smoothing process, thereby suppressing noise interference while preserving the trend of cut quality change. If the value is too small, the prediction result will jump drastically and lose continuity. If the value is too large, it may mask the real quality gradient change. Setting it to one-third of the segment length is based on the principle of empirical optimization and error propagation control. Mapping weighting is performed within the 90% energy concentration range of the Gaussian function, which is a balance option between quality continuity and sensitivity.

[0088] S3: Optimize the initial machining trajectory based on the cut quality prediction parameters, generate an anti-tear machining trajectory, and control the operation of the actuator.

[0089] S3 specifically includes:

[0090] S31, Trajectory Optimization Modeling: To reduce the risk of fiber tearing while ensuring processing geometric accuracy, a dual-objective optimization model is constructed, taking into account both trajectory point deviation and the full-path integral of the tear index. Its objective function is expressed as:

[0091]

[0092] Constraints:

[0093] Where, n p q represents the total number of trajectory points. i These are the coordinates of the optimized trajectory points, p i Here, ε(s) represents the coordinates of the design contour points, ε(s) is the fiber tearing index at arc length s, with a value range of [0,1], which helps to unify the evaluation scale and facilitates normalization processing for the optimization model. γ(s) is the angle between the trajectory tangent and the fiber direction (γ(s)≥40°). A value less than 40° easily causes fiber tearing; setting it to 40° ensures that the angle between the trajectory and the fiber is within a safe range, serving as the lower limit for tear protection. k(s) is the trajectory curvature; limiting the curvature ensures trajectory smoothness and equipment processing capacity, not exceeding 80% of the equipment's limits. H b(s) is the burr height gradient at arc length s, w1 and w2 are optimization weight coefficients, satisfying w1 + w2 = 1, and w2 takes values ​​from 0.6 to 0.8. max It is the maximum permissible curvature, taken as 80% of the processing equipment's limit. This provides a certain safety margin to prevent trajectory oscillation or processing failure due to extreme loads. H max It is the burr height threshold, H max =0.05mm, which is the standard requirement for edge smoothness in precision machining. Exceeding 0.05mm will affect the quality of assembly or products. L is the total arc length of the machining path.

[0094] S32, Laser-Assisted Softening Integration: To perform localized softening treatment on machining areas with high tear risk and improve material machinability, this method is applied to areas where the tear index exceeds the tear risk threshold (i.e., ε(s) > ε). th Apply laser preprocessing, and set the energy and scanning speed as follows:

[0095]

[0096] Among them, P laser This refers to the laser power, ranging from 10 to 100 W. Values ​​exceeding 100 W can easily cause carbonization and delamination, while values ​​below 10 W result in insufficient softening. This range balances efficiency and quality. scan This refers to the laser scanning speed, measured in mm / s, σ. y T is the material's yield strength, ranging from 150 to 400 MPa. The yield strength determines the critical stress at which the material begins plastic deformation, affecting the energy required for softening. It is a fundamental parameter for setting laser power. T' is the plate thickness, ranging from 1 to 5 mm. Thicker plates have longer heat diffusion paths and higher laser energy requirements; thickness directly affects power. Δε is the tear index overscalar value, Δε = ε(s) - ε th Δε∈[0,0.5], the greater the degree of exceeding the limit, the higher the risk of tearing, and the laser softening intensity needs to be increased simultaneously; the range limitation is used to avoid overheating processing, ε th It is the tear risk threshold, ε th =0.7, when ε th A value >0.7 significantly increases fiber breakage rate and edge delamination risk; therefore, 0.7 was selected as the softening trigger threshold. p This is the power coefficient, ranging from 0.15 to 0.25. Taking into account the thermal sensitivity of different materials and processing requirements, this power coefficient adjusts the sensitivity of the laser output, ensuring sufficient softening without overheating. cut This is the basic cutting speed, with a value range of 5-50, and the unit is mm / s;

[0097] S33, chatter compensation generation: When crack density is detected to exceed the critical crack density threshold (ρ) c (s)>ρ crit In order to reduce the chatter effect between the tool and the workpiece, normal compensation is implemented to suppress vibration, as shown below:

[0098]

[0099] Where δ(s) is the normal compensation displacement, which is the trajectory fine-tuned in the high crack density region to alleviate processing vibration, and the unit is mm; A is the compensation amplitude. The value range is 0-0.05, which can avoid structural processing offsets and errors. Compensation is turned off when A approaches 0. c This refers to the fiber resonant frequency, ranging from 150 to 500 Hz. Based on modal analysis results of typical FRP sheets, frequencies falling within this range can be effectively superimposed and coupled with fiber vibration modes, enhancing the compensation response. cut ζ is the basic cutting speed, ranging from 20 to 80, which directly affects the excitation frequency matching period and the actual sampling frequency of the compensation displacement. ζ is the vibration attenuation coefficient, ranging from 0.05 to 0.1, used to simulate the rapid decrease in oscillation amplitude after cutting in, ensuring compensation convergence. c (s) represents the microcrack density, ranging from 0 to 12, with units of cracks / mm. Based on microcrack detection modeling, areas exceeding 8 cracks / mm are considered high-risk areas for potential instability, requiring the activation of a compensation mechanism. ρ crit It is the critical threshold of crack density, ρ crit =8. Based on experimental statistical analysis, when the crack density exceeds 8 cracks / mm, the local stiffness of the structure decreases significantly, necessitating the triggering of active vibration suppression strategies. It is the phase lag angle, which adjusts with the direction of the rate of change of the included angle, and its value range is... or It can achieve synchronous phase modulation between the compensation signal and the direction of change of the trajectory-fiber angle, improve the consistency between the compensation and the disturbance direction, and avoid phase cancellation;

[0100] S34, Actuator Coordinated Control: After trajectory optimization, to ensure the processing is sensitive to tearing, cracking, and resonance signals, it is necessary to coordinate and control the equipment execution units, converting the optimized trajectory results into equipment operation control commands, expressed as:

[0101]

[0102]

[0103] Where N is the tool spindle speed, ranging from 3000 to 12000 rpm, dynamically adjusted based on the cutting material and tear sensitivity. Higher speeds are beneficial for surface finish, but if the tear index gradient is too large, the speed will be appropriately reduced through function adjustment. D is the tool diameter, ranging from 1 to 10 mm. The diameter affects the spindle speed conversion and chip width. f This refers to the feed rate, which ranges from 20 to 80, and is expressed in mm / s. This is the time derivative of the compensation displacement, with a value range of [-1.5, 1.5], ensuring path smoothness. T laser It is the laser activation time point, T laser <2, unit is seconds. The laser needs to be started in advance to cover the softened area in front, ensuring that the material has been fully heat-treated before processing. T tool This refers to the time it takes for the tool to reach the control point. Laser activation is coordinated with this parameter, and the lead time ensures synchronized operation. (L) pre This is the laser softening pre-scan length. The pre-scan length must cover the thermal diffusion zone. The recommended value is 3 times the spot diameter to prevent laser lag from causing the material to not soften sufficiently.

[0104] like Figure 2 As shown, a control system for ship plate processing equipment, used to implement the above-mentioned control method for ship plate processing equipment, includes the following modules:

[0105] Fiber orientation detection and trajectory initialization module: detects the main orientation of the rolled fibers of the ship plate to be processed, combines it with the preset target contour information, generates the initial processing trajectory and performs standardized coding;

[0106] Fiber-trajectory coupling quality prediction module: Input the initial processing trajectory into the constructed fiber-trajectory coupling model, input variables based on the board properties, fiber direction and trajectory geometric parameters, and output a set of cut quality prediction parameters that reflect tear risk and defect trend;

[0107] The trajectory optimization and execution control module optimizes the initial trajectory based on the cut quality prediction parameters, constructs a multi-objective optimization path by combining geometric accuracy and tear sensitivity, and converts the final tear-resistant processing trajectory into control commands to drive the actuator to complete the processing task.

[0108] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity.

Claims

1. A control method for ship plate processing equipment, characterized in that, Includes the following steps: S1: Detect the rolling fiber direction of the sheet material to be processed and generate an initial processing trajectory based on the target contour; S2: Input the initial processing trajectory into the fiber-trajectory coupling model and output the cut quality prediction parameters; S3: Optimize the initial processing trajectory based on the cut quality prediction parameters, generate an anti-tear processing trajectory, and control the operation of the actuator.

2. The control method for ship plate processing equipment according to claim 1, characterized in that, S1 includes: S11, Detection of rolled fiber direction: The surface of the board is scanned by an eddy current sensor, and the overall fiber flow angle of the board is calculated based on the difference in conductivity in different directions. S12, Fiber reliability verification: The aspect ratio of the grains is analyzed by metallographic image sampling and compared with the eddy current detection results to determine whether there is a clear fiber flow direction and to verify the reliability of the orientation angle. S13, Initial processing trajectory generation: Combine the target contour point set with the detected fiber direction to construct the initial processing trajectory; S14, Trajectory Smoothing Processing: The initial trajectory is optimized, taking into account the smoothness of the path curvature and the tear resistance direction angle requirements. The position of the trajectory points is adjusted on the premise that the processing error does not exceed the maximum allowable error threshold of the trajectory offset.

3. The control method for ship plate processing equipment according to claim 2, characterized in that, S13 includes: S131, Contour point set construction and orientation information fusion: After obtaining the overall fiber flow angle of the board, extract the contour point set of the target processing area; S132, Trajectory Weight Function Calculation and Initial Path Generation: Based on the angle relationship between the geometric contour and the fiber direction, a trajectory weighting function that comprehensively considers processing accuracy and tear resistance is constructed. The trajectory optimization weight is calculated segment by segment to generate an initial processing trajectory with directional protection capability.

4. The control method for ship plate processing equipment according to claim 2, characterized in that, S14 includes: S141, Curvature and orientation constraint optimization modeling: Under the premise of keeping the trajectory points close to the original contour, an optimization model that comprehensively considers the smoothness of trajectory curvature and fiber orientation protection is constructed. The path segments that deviate from the optimal orientation angle are restricted by the penalty term, and the curvature change between trajectory points is controlled. S142, Trajectory point position update and error limit: Optimize and adjust the initial trajectory points to generate a new trajectory point sequence.

5. The control method for ship plate processing equipment according to claim 4, characterized in that, S2 includes: S21, Trajectory Discretization Processing: The initial processing trajectory is subdivided according to the directional change trend and curvature feature points to generate multiple trajectory micro-segments. The length of each micro-segment is set according to the minimum value of the angle between the radius of curvature and the fiber direction. S22, Cutting state calculation: Based on the trajectory micro-segment, a cutting dynamics response model is constructed to calculate the main cutting force and the radial vibration force caused by fiber resonance respectively; S23, Cut quality parameter prediction: Based on the calculated cutting force results, predict three cut quality indicators for each micro-segment, including burr height gradient, microcrack density and fiber tear index. S24, Parameter Space Mapping: The cut quality prediction parameters of the micro-segment are weighted by a Gaussian kernel function and mapped to the continuous trajectory coordinate system to obtain a continuous cut quality prediction vector that varies with position.

6. The control method for ship plate processing equipment according to claim 5, characterized in that, S23 includes: S231, Burr height gradient calculation: Calculate the burr height gradient based on the degree of non-uniform deformation of the edge under the action of cutting force; S232, Microcrack density prediction: Calculate the microcrack density by combining the fiber attenuation effect caused by the angle factor and the change rate of the main cutting force; S233, Fiber tear index estimation: The fiber tear index is calculated by using an S-shaped function to express the abrupt behavior of tear damage after exceeding the tear critical force threshold.

7. The control method for ship plate processing equipment according to claim 5, characterized in that, S24 includes: S241, Trajectory Coordinate System Parameter Projection: Mapping the cut quality parameters obtained for each trajectory micro-segment to the corresponding position points in the trajectory coordinate system; S242, Gaussian weighted smooth fusion: The quality parameter values ​​of each mapped cut are weighted and superimposed using a Gaussian kernel function.

8. The control method for ship plate processing equipment according to claim 7, characterized in that, S3 includes: S31, Trajectory Optimization Modeling: Construct a dual-objective optimization model that comprehensively considers geometric contour deviation and fiber tear index. Through trajectory point offset and integral risk control, the optimal processing path is achieved, while setting constraints on included angle, curvature and burr height. S32, Laser-Assisted Softening Integration: For trajectory segments with a high risk of tearing, a laser softening operation is introduced, and the laser power and scanning speed are dynamically calculated based on the degree of exceeding the tear index. S33, Flutter Compensation Generation: When the crack density exceeds the critical threshold of crack density, the normal compensation strategy is activated to generate an attenuated sinusoidal displacement signal based on the fiber vibration frequency and crack density information. S34, Actuator Cooperative Control: Transforms optimized trajectory and laser processing information into equipment control commands.

9. A control method for ship plate processing equipment according to claim 8, characterized in that, S31 includes: S311, Establish a dual-objective optimization function: Construct a dual-objective optimization model that includes a geometric deviation term and a tearing index integral term, and coordinate the importance of the two objectives through weighting coefficients; S312, Set multiple constraints: Introduce three processing stability constraints.

10. A control system for ship plate processing equipment, used to implement the control method for ship plate processing equipment as described in any one of claims 1-9, characterized in that, Includes the following modules: Fiber orientation detection and trajectory initialization module: detects the main orientation of the rolled fibers of the ship plate to be processed, combines it with the preset target contour information, generates the initial processing trajectory and performs standardized coding; Fiber-trajectory coupling quality prediction module: Input the initial processing trajectory into the constructed fiber-trajectory coupling model, input variables based on the board properties, fiber direction and trajectory geometric parameters, and output a set of cut quality prediction parameters that reflect tear risk and defect trend; The trajectory optimization and execution control module optimizes the initial trajectory based on the cut quality prediction parameters, constructs a multi-objective optimization path by combining geometric accuracy and tear sensitivity, and converts the final tear-resistant processing trajectory into control commands to drive the actuator to complete the processing task.

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