Numerical control curve cutting tool shaft trajectory correction control method, device, equipment and medium

Abstract

The present application relates to a kind of numerical control curve cutting cutter shaft track correction control method, device, equipment and medium, the method gathers curve data to be processed and demarcates cutter tip target travel path;Curve with analytical expression is solved by function derivation to the tangent direction, and for discrete curve, external reference point and sampling point are selected to construct polygon, and tangent is approximately solved by geometric operation.Sets cutter tip to cutter shaft fixed spacing as tangent segment with cut point as reference, generates cutter shaft center point by equidistant offset along tangent extension direction, obtains cutter shaft travel track, and cutter shaft point is located in front of cutter tip travel tangent.Drives cutter shaft center translation movement, keeps cutter tip and cutter shaft line constant and tangent to processing curve, stratified adaptation general form curve, circular arc, straight circular compound profile, corrects cutting track error caused by bias spacing, avoids circular arc edge corner distortion, matches smooth trajectory of tangential entry and exit, improves mobile phone, tablet computer type protective film cutting precision and yield.

Description

Technical Field

[0001] This invention relates to the field of CNC film material cutting technology, and in particular to a method, device, equipment and medium for correcting and controlling the tool axis trajectory of CNC curve cutting. Background Technology

[0002] Currently, CNC curve cutting of protective films for electronic products such as mobile phone screen protectors and tablet screen protectors generally adopts a tip-off type translational cutting head. The tip of the cutting head has a fixed distance from the center of the drive shaft, and the cutting edge is tilted relative to the shaft axis. The cutting head lacks an active rotation drive mechanism; during cutting and feeding, it is passively rotated by the reaction force of the film material. The equipment can only directly control the center of the shaft to complete the displacement movement. Existing cutting control schemes are generally suitable for linear curve processing. The tangent extension direction of straight segments is constant, and the offset distance can be corrected by directly making equidistant offsets along the tangent extension direction. However, product curves often include rounded corners, arcs, and composite curves connecting straight lines and arcs. Traditional control methods do not distinguish between the tangent and its extension direction, which change in real time at each point on the curve. Directly applying straight-line offset logic will cause the curve corners to shrink or expand outwards. Traditional methods rely on calculating the tangent direction point by point using the curve's analytical equation. The computation is difficult to complete for discrete sampling curves without analytical methods, requiring additional high-precision curve fitting modules, which increases hardware costs. Furthermore, simplified geometric calculation logic is not provided for circular, arc, and straight-circle transition curves; a general point-by-point offset algorithm is executed throughout, resulting in high system computation and slow equipment cutting response. Additionally, traditional processing lacks corresponding offset trajectories for tangential entry and exit cuts; vertical cuts and direct cut retraction leave obvious cutting marks and burrs on the protective film edge, significantly reducing the yield of finished films for electronic products. Summary of the Invention

[0003] The main objective of this invention is to provide a method, device, equipment, and medium for correcting the tool axis trajectory in CNC curve cutting. This invention constructs the target tool tip travel path using the target curve of the electronic product film. It uses external reference points combined with discrete sampling points to geometrically solve the curve tangent. The tool axis center trajectory is generated by equidistant offset along the extension direction of the curve tangent segment, categorized into three types: general curves, circular arcs, and composite curves of straight lines and circular arcs. This is complemented by tangential entry and exit offset trajectory control to control the overall translation of the tool head during machining. It is suitable for tool tip offset cutting heads with blade tilt and passive follow-rotation, thereby correcting trajectory errors caused by the offset distance between the tool tip and the tool axis center, eliminating curve cutting deformation, and improving the cutting accuracy and finished product appearance yield of the electronic product film curve edge.

[0004] To achieve the above objectives, the present invention provides a tool axis trajectory correction control method for CNC curve cutting, comprising the following steps:

[0005] Obtain the curve data of the curve to be processed, and determine the curve to be processed as the target travel path of the tool tip;

[0006] Select reference points and construct a geometric figure by combining the sampling points on the target travel path of the cutting tip. Calculate the tangent direction of the curve corresponding to the sampling points through the geometric figure. Using the sampling points as the tangent points, take the fixed-distance line segment from the cutting tip to the center of the cutting axis as the tangent line segment of the curve.

[0007] Using the sampling points on the target travel path of the cutting tip as a reference, offset along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting tip to the center of the cutting axis, each sampling point is obtained as the corresponding center point of the cutting axis. All the center points of the cutting axis are connected in the order of the sampling points to generate the actual travel trajectory of the center of the cutting axis. The center point of the cutting axis is located in front of the tangent line of the cutting tip sampling point along the curve.

[0008] The control tool axis center moves along the actual travel trajectory of the tool axis center. The tool axis center moves continuously along the actual travel trajectory of the tool axis center. The line connecting the tool tip and the tool axis center is always tangent to the target travel path of the tool tip. The tool tip performs cutting processing according to the curve to be processed.

[0009] Further, the step of acquiring the curve data of the curve to be processed and determining the curve to be processed as the target travel path of the tool tip includes:

[0010] Identify the geometric type of the curve to be processed;

[0011] If the curve to be processed is a discrete curve without an analytical expression, collect data from multiple discrete sampling points on the curve to be processed, perform continuous curve fitting on the multiple discrete sampling points to generate a smooth and continuous curve to be processed, and determine the smooth and continuous curve to be processed generated by fitting as the target travel path of the tool tip.

[0012] If the curve to be processed has an analytical function expression, the corresponding analytical function expression is directly retrieved to generate a continuous curve to be processed and determine it as the target travel path of the tool tip.

[0013] Further, the steps include selecting reference points, constructing a geometric figure by combining the sampling points on the target travel path of the tool tip, calculating the tangent direction of the curve corresponding to the sampling points using the geometric figure, and taking the sampling points as the tangent points and the fixed-distance line segment from the tool tip to the center of the tool axis as the tangent line segment of the curve, including:

[0014] Select a reference point outside the target's travel path;

[0015] Connect the reference points with two adjacent sets of sampling points on the target's travel path to form a closed polygon.

[0016] Calculate the approximate tangent direction corresponding to the sampling point based on the positional relationship of each side of the closed polygon;

[0017] Using the current sampling point as the tangent point, extend the line segment with a length equal to the fixed distance from the tip of the tool to the center of the tool axis along the tangent direction to obtain the tangent line segment from the tip of the tool to the center of the tool axis.

[0018] Further, taking the sampling points on the target travel path of the cutting edge as a reference, offset along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, each sampling point is obtained as the corresponding center point of the cutting axis. Connecting all the center points of the cutting axis in the order of the sampling points generates the actual travel trajectory of the cutting axis center. The step of the cutting axis center point being located in front of the sampling point of the cutting edge along the travel direction includes:

[0019] Select all sampling points along the target travel path of the blade tip in sequence, and determine the extension direction of the curve tangent line segment corresponding to each sampling point;

[0020] Using each sampling point on the target travel path of the cutting edge as a reference, move along the tangent line segment of the corresponding sampling point by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, and obtain the center point of the cutting axis corresponding to each sampling point.

[0021] Connect all the center points of the cutter axis in sequence according to the corresponding sampling points to generate a continuous actual travel trajectory of the cutter axis center.

[0022] Further, taking the sampling points on the target travel path of the cutting edge as a reference, offset along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, each sampling point is obtained as the corresponding center point of the cutting axis. Connecting all the center points of the cutting axis in the order of the sampling points generates the actual travel trajectory of the cutting axis center. The step of the cutting axis center point being located in front of the sampling point of the cutting edge along the travel direction also includes:

[0023] If the target path of the blade tip is circular or arc-shaped, determine the center position and radius of the circular or arc-shaped curve;

[0024] Using the same center position as a reference, the radius of the tool axis center trajectory is determined by combining the fixed distance from the tool tip to the center of the tool axis;

[0025] Based on the determined center position and the radius of the tool axis center trajectory, the actual travel trajectory of the tool axis center is generated as a concentric circle with the travel path of the tool tip target.

[0026] Further, taking the sampling points on the target travel path of the cutting edge as a reference, offset along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, each sampling point is obtained as the corresponding center point of the cutting axis. Connecting all the center points of the cutting axis in the order of the sampling points generates the actual travel trajectory of the cutting axis center. The step of the cutting axis center point being located in front of the sampling point of the cutting edge along the travel direction also includes:

[0027] If the target travel path of the tool tip is composed of straight segments and circular arc segments connected tangentially, distinguish between two connection sequences along the machining travel direction: straight segments connecting to circular arc segments and circular arc segments connecting to straight segments, and extract the curve parameters of the straight segments and circular arc segments respectively.

[0028] The straight line segment extending along the tangent is offset by a distance equal to the fixed distance from the tool tip to the center of the tool axis, thus obtaining the corresponding straight line trajectory segment of the tool axis center;

[0029] The arc segment is processed using a concentric circle offset method to obtain the corresponding arc trajectory segment of the tool axis center;

[0030] Calculate the corresponding transition correction angle based on the current connection sequence, and determine the coordinates of the connection point between the straight trajectory segment and the circular trajectory segment of the tool axis center based on the transition correction angle, so that the two trajectories are tangent to each other at the connection point, generating a complete actual travel trajectory of the tool axis center.

[0031] Further, the steps of controlling the center of the cutter axis to translate along the actual travel trajectory of the cutter axis, the continuous movement of the center of the cutter axis along the actual travel trajectory of the cutter axis, and the line connecting the cutter tip and the center of the cutter axis always being tangent to the target travel path of the cutter tip, and the cutter tip performing cutting processing according to the curve to be processed, include:

[0032] Set the entry point at the starting position of the target travel path of the tool tip, generate an entry lead line that extends from the outside of the curve to the entry point and is tangent to the curve, and generate the corresponding tool axis offset trajectory of the entry lead line.

[0033] Set the exit point at the end of the target travel path of the tool tip, generate an exit lead line that extends from the exit point to the outside of the curve and is tangent to the curve, and generate the corresponding tool axis offset trajectory of the exit lead line.

[0034] The control tool axis center moves along the tool axis offset trajectory of the tool entry line to the tool entry position, and then performs the main curve cutting along the actual travel trajectory of the tool axis center. The workpiece is then moved out along the tool axis offset trajectory of the tool exit line to complete the complete curve cutting process.

[0035] The present invention also provides a tool axis trajectory correction control device for CNC curve cutting, comprising:

[0036] The data acquisition module is used to acquire the curve data of the curve to be processed and to determine the curve to be processed as the target travel path of the tool tip;

[0037] The direction determination module is used to select reference points, construct a geometric figure by combining the sampling points on the target travel path of the cutting tip, calculate the tangent direction of the curve corresponding to the sampling point through the geometric figure, and take the sampling point as the tangent point, and take the fixed distance line segment from the cutting tip to the center of the cutting axis as the tangent line segment of the curve.

[0038] The trajectory generation module is used to take the sampling points on the target travel path of the cutting tip as a reference, offset along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting tip to the center of the cutting axis, to obtain the corresponding cutting axis center point of each sampling point, and connect all the cutting axis center points in the order of sampling points to generate the actual travel trajectory of the cutting axis center. The cutting axis center point is located in front of the cutting tip sampling point along the tangent line of the curve.

[0039] The path cutting module is used to control the center of the cutter shaft to translate along the actual travel trajectory of the cutter shaft center. The center of the cutter shaft center moves continuously along the actual travel trajectory of the cutter shaft center. The line connecting the cutter tip and the center of the cutter shaft is always tangent to the target travel path of the cutter tip. The cutter tip performs cutting processing according to the curve to be processed.

[0040] The present invention also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the above-described CNC curve cutting tool axis trajectory correction control method.

[0041] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the above-described CNC curve cutting tool axis trajectory correction control method.

[0042] The tool axis trajectory correction control method, device, equipment, and medium for CNC curve cutting provided by this invention have the following beneficial effects:

[0043] This invention constructs polygonal geometry using external reference points to solve for tangent directions, achieving approximate differentiation solely through discrete sampling points. It also supports precise analytical function solutions, adapting to various irregular non-analytical curves and standard regular curves, thus lowering the computational threshold for CNC equipment. By layering three sets of calculation logic—point-by-point offset for general curves, simplified offset for concentric circles of arcs, and segmented tangential offset for straight circles—the general algorithm covers all curves. For composite arc curves, a geometrically simplified formula is used, significantly reducing system computation and improving cutting trajectory generation efficiency. Using the target tool tip travel path as a unified benchmark, the tool axis trajectory is generated by equidistant offset along the curve tangent segment extension direction. The entire process corrects for cutting trajectory errors caused by the offset between the tool tip and the tool axis center. The tool tip can accurately conform to the target curve at all positions, solving the problem of arc corner dimensional deformation. It adapts to tool head structures with blade tilt and passive follow-rotation, improving the machining accuracy of protective film curves. In addition, it is equipped with tangential entry and exit guide lines and synchronously generates offset trajectories. The cutter head moves in translation throughout the entire process without active rotation. The entry, main body cutting, and exit trajectories are continuous and smooth, eliminating workpiece edge marks and burr defects, improving product appearance quality and processing yield. The entire method logic can be adapted to high-precision cutting production of electronic product films in batches. Attached Figure Description

[0044] Figure 1 This is a flowchart illustrating the tool axis trajectory correction control method for CNC curve cutting in one embodiment of the present invention;

[0045] Figure 2 This is a schematic diagram illustrating the general form of the offset mapping between the tool tip trajectory and the tool axis center trajectory in this invention;

[0046] Figure 3 This is a schematic diagram showing the relationship between the circular curved blade tip trajectory and the blade center trajectory of the present invention;

[0047] Figure 4 This is a schematic diagram of the tool center trajectory for the transition curve from a straight line to a circular arc in this invention;

[0048] Figure 5 This is a schematic diagram of the tool center trajectory for the transition curve from an arc to a straight line in this invention;

[0049] Figure 6 This is a schematic diagram of the cutting path of a blade tip offset translational cutting head in one embodiment of the present invention;

[0050] Figure 7 This is a schematic diagram of the structure of a blade tip offset translational cutting head in one embodiment of the present invention;

[0051] Figure 8 This is a structural block diagram of a tool axis trajectory correction control device for CNC curve cutting according to an embodiment of the present invention;

[0052] Figure 9 This is a schematic block diagram of the structure of a computer device according to an embodiment of the present invention.

[0053] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0055] Reference Figure 1 This is a flowchart illustrating a tool axis trajectory correction control method for CNC curve cutting proposed in this invention, comprising the following steps:

[0056] S1, Obtain the curve data of the curve to be processed, and determine the curve to be processed as the target travel path of the tool tip;

[0057] S2, select reference points, construct a geometric figure by combining the sampling points on the target travel path of the cutting tip, calculate the tangent direction of the curve corresponding to the sampling point through the geometric figure, take the sampling point as the tangent point, and take the fixed distance line segment from the cutting tip to the center of the cutting axis as the tangent line segment of the curve.

[0058] S3, taking the sampling points on the target travel path of the cutting tip as the reference, offset along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting tip to the center of the cutting axis, to obtain the corresponding cutting axis center point of each sampling point, connect all the cutting axis center points in the order of sampling points to generate the actual travel trajectory of the cutting axis center, wherein the cutting axis center point is located in front of the cutting tip sampling point along the tangent line of the curve;

[0059] S4, control the center of the cutter shaft to translate along the actual travel trajectory of the cutter shaft center. The center of the cutter shaft center continues to move along the actual travel trajectory of the cutter shaft center. The line connecting the cutter tip and the center of the cutter shaft is always tangent to the target travel path of the cutter tip. The cutter tip performs cutting processing according to the curve to be processed.

[0060] As described in step S1 above, this step is used to establish the reference trajectory for cutting. The workpiece to be processed in this invention is specifically a protective film for various electronic products such as mobile phone films and tablet films. The outer curves of such products often contain rounded corners, arc edges, and other curved structures, which have high requirements for curve size accuracy and edge smoothness. First, the corresponding curve data of the curve to be processed is obtained. The data can come from a preset processing drawing file or the acquisition results of the curve acquisition device. The obtained curve to be processed is directly determined as the target travel path of the cutting tip. This path corresponds to the accurate position that the cutting tip needs to pass through when cutting the workpiece. It is the only reference for all subsequent trajectory offset calculations, ensuring that the subsequent offset calculations have a unified reference standard, thereby avoiding the final cutting curve size deviation caused by inconsistent references, and providing basic support for high-precision cutting of electronic product films.

[0061] As described in step S2 above, this step is used to solve for the normal direction of each position of the curve, providing an accurate directional basis for subsequent trajectory offset. For curves with standard analytical equations, the tangent direction of each point can be accurately solved directly through function differentiation. Considering that most electronic product film curves do not have standard analytical equations and only have discrete point data, a reference point outside the target travel path of the cutting tip is selected. The reference point is connected to the adjacent sampling point on the target travel path of the cutting tip by a straight line to form a closed polygonal geometry. The approximate curve tangent direction of the corresponding sampling point is calculated through the geometric positional relationship of each side of the polygon. Taking the current sampling point as the cutting tangent point, a line segment with a length equal to the fixed distance L from the cutting tip to the center of the cutting axis is extended forward along the tangent direction. This line segment is the connecting line segment between the cutting tip and the center of the cutting axis. The cutting tip is located at the tangent point, and the center of the cutting axis falls at the front end of the tangent line segment along the travel direction. The cutting tip is arranged with a lag relative to the center of the cutting axis. This replaces the direct differentiation method, reduces the dependence on the analytical expression of the curve, and adapts to the calculation needs of various irregular curves. Taking the current sampling point as the cutting tangent point, the line segment with a length equal to the fixed distance L from the tool tip to the center of the tool axis is extended forward along the tangent direction. This line segment is the connecting line segment between the tool tip and the center of the tool axis. The tool tip is located at the tangent point, and the center of the tool axis falls on the front end of the tangent line segment along the travel direction.

[0062] As described in step S3 above, this step is the core of the tool axis trajectory offset calculation, used to solve the problem of curve cutting distortion caused by the fixed offset distance of the tool head. Since there is a fixed distance between the cutting tip and the center of the tool axis, the CNC equipment can only directly control the movement position of the tool axis center. If the tool axis center is directly controlled to move along the target travel path of the tool tip, the actual cutting position of the tool tip will deviate from the target curve, causing problems such as dimensional deviation of the cut electronic product film curve and deformation of the arc corners. Therefore, the system takes each sampling point on the target travel path of the tool tip as a reference, and offsets it by a distance equal to the fixed distance between the tool tip and the center of the tool axis along the extension direction of the curve tangent line segment pre-determined for the corresponding sampling point, to obtain the tool axis center point corresponding to each sampling point. Then, all the tool axis center points are connected in sequence according to the order of the corresponding sampling points to generate a continuous and smooth actual travel trajectory of the tool axis center. This trajectory is the actual path that the tool axis center needs to run. It can correct the offset distance in the reverse direction when the tool head moves, ensuring that the tool tip always falls on the accurate position of the target curve.

[0063] As described in step S4 above, this step is the execution stage of the cutting process. Based on the actual travel trajectory of the generated cutter axis center, motion control commands are output. Throughout the cutting process, the line segment connecting the cutter tip and the cutter axis center is always tangent to the target travel path of the cutter tip, driving the cutting head to perform an overall translational motion. During the cutting process, the blade orientation is always consistent with the overall travel direction of the cutter head, and the cutter axis center moves continuously according to the actual travel trajectory of the cutter axis center. The fixed distance deviation between the cutter tip and the cutter axis center is offset by the pre-calculated normal offset, so that the cutter tip always accurately follows the curve to be processed, and finally completes the full curve cutting process on electronic product film workpieces such as mobile phone films and tablet films. This control method can ensure the cutting accuracy of various rounded corners and curves, avoid curve distortion at curve bends, and ensure that the cutting size and edge smoothness of electronic product films meet the processing requirements.

[0064] The method of this invention is adapted to a tip-off type translational cutting head. This head has a fixed offset distance between the cutting tip and the center of the cutting axis, and the cutting edge is inclined relative to the axis. The cutting axis center serves only as a reference for the device to drive the planar displacement of the cutting head. During cutting, the cutting edge is subjected to the reaction force of the workpiece, causing the cutting head to passively rotate around the cutting axis center, automatically aligning the cutting edge with the feed direction. The cutting tip always lags behind the travel direction of the cutting axis center. If the cutting edge orientation is forcibly adjusted using the cutting axis center as the rotation reference, the cutting tip will generate radial arc displacement with the rotation, causing the cutting point to shift and the curved cutting trajectory to deviate from the preset cutting tip path. This method uses the cutting tip as the motion reference point and corrects the trajectory deviation caused by the offset distance through the trajectory deviation of the cutting axis center. During passive rotation, the cutting tip coordinates remain constantly coincident with the preset cutting point, eliminating the cutting position deviation from the cutting head motion structure level and providing reliable motion constraints for cutting axis trajectory correction calculations.

[0065] In one embodiment, step S1, which involves acquiring the curve data of the curve to be processed and determining the curve to be processed as the target travel path of the tool tip, includes:

[0066] Identify the geometric type of the curve to be processed;

[0067] If the curve to be processed is a discrete curve without an analytical expression, collect data from multiple discrete sampling points on the curve to be processed, perform continuous curve fitting on the multiple discrete sampling points to generate a smooth and continuous curve to be processed, and determine the smooth and continuous curve to be processed generated by fitting as the target travel path of the tool tip.

[0068] If the curve to be processed has an analytical function expression, the corresponding analytical function expression is directly retrieved to generate a continuous curve to be processed and determine it as the target travel path of the tool tip.

[0069] In practical implementation, for the cutting and processing of protective films for electronic products such as mobile phone screen protectors and tablet screen protectors, multiple discrete sampling point data on the curve to be processed are collected. The point data can be obtained by reading the curve coordinate information in the standard processing graphic file, or by scanning the product standard template with a vision acquisition device. After acquiring the curve data, the geometric type of the curve to be processed is first identified: identification can be completed by directly reading the primitive type identifier attached to the processing file, or it can be automatically determined by the geometric characteristics of the point coordinates. If the curve to be processed is a discrete irregular curve without an analytical expression, the sampling process takes points sequentially along the extension direction of the curve. The sampling points are densified in areas with large curvature changes such as rounded corners and arc edges, and the sampling interval is appropriately increased in straight and gentle sections. The overall data processing volume is controlled while completely preserving the curve shape characteristics. All sampling points are stored in an orderly manner according to the processing progress of the curve, forming a discrete point set corresponding to the curve to be processed. For complex curves without a clear analytical expression, the overall curve is broken down into multiple shorter, simpler curves. During this breakdown, the starting point of each short curve is used as the local origin to simplify subsequent fitting and offset calculations. Polynomial curve fitting is performed on the discrete sampling points corresponding to each short curve to generate a smooth and continuous curve to be processed. The fitted tool tip trajectory curve is denoted as f(x). The planar coordinates of any point on the curve can be mapped one-to-one using a functional relationship. The fitted curve passes through all the original sampling points sequentially, and the curve as a whole is continuous and smooth, eliminating the stepped feel caused by discrete points. This also provides a continuous geometric calculation basis for subsequent tangent direction calculation and trajectory offset calculation. If the curve to be processed has a standard analytical function expression (such as a straight line, arc, or standard quadratic curve), the analytical function is directly invoked to generate a continuous and accurate curve to be processed, eliminating the need for discrete sampling and fitting steps. The subsequent tool axis center trajectory can be directly solved through the point-to-point mapping relationship of the original curve. After the curve is constructed, the smooth and continuous curve to be processed is determined as the target travel path of the tool tip. This path corresponds to the theoretically accurate position that the tool tip needs to pass through when cutting the workpiece. All subsequent tangent and normal calculations and tool axis trajectory offset calculations are based on this path as a unified reference to ensure that the calculation reference is consistent throughout the process and to avoid the cumulative error caused by reference switching, so as to ensure the cutting dimension accuracy and edge smoothness of the film curve of electronic products.

[0070] In one embodiment, step S2, which involves selecting a reference point, constructing a geometric figure by combining the sampling points on the target travel path of the cutting edge, calculating the tangent direction of the curve corresponding to the sampling point using the geometric figure, and taking the sampling point as the tangent point and the fixed-distance line segment from the cutting edge to the center of the cutting axis as the tangent line segment of the curve, includes:

[0071] Select a reference point outside the target's travel path;

[0072] Connect the reference points with two adjacent sets of sampling points on the target's travel path to form a closed polygon.

[0073] Calculate the approximate tangent direction corresponding to the sampling point based on the positional relationship of each side of the closed polygon;

[0074] Using the current sampling point as the tangent point, extend the line segment with a length equal to the fixed distance from the tip of the tool to the center of the tool axis along the tangent direction to obtain the tangent line segment from the tip of the tool to the center of the tool axis.

[0075] In practical implementation, for curves in products such as mobile phone screen protectors and tablet screen protectors that lack standard analytical equations and are difficult to directly differentiate, this invention selects reference points located outside the target's travel path. These reference points are fixed points used for auxiliary calculations, set on the curve offset side, and maintained at a reasonable distance from the target's travel path. They are used to replace calculus differentiation calculations with pure geometric methods, reducing the computational threshold for curve trajectories. After selecting the reference points, for each target sampling point to be calculated, two adjacent sampling points are selected before and after the target sampling point. These, together with the external reference points, construct a closed polygon. The external reference points are then sequentially connected to the two adjacent sets of sampling points and the target sampling point with straight lines. Combined with the connecting line segments along the curve between the sampling points, a closed polygonal geometric figure is formed. Each side of the polygon is a straight line segment that can be directly calculated using coordinates, and the positional and angular relationships of each side can be solved using plane geometric formulas. After the polygon is constructed, the approximate tangent direction corresponding to the sampling point is calculated based on the positional relationship of each side of the closed polygon. The approximate tangent slope at the target sampling point is calculated by the line segment coordinate difference between adjacent sampling points in the polygon. The first derivative value f'(x) of the tool tip trajectory curve f(x) at that point is corresponding to this slope. Then, the angle θ between the tangent direction and the horizontal axis of the coordinate system is obtained by arctangent operation, satisfying the relationship θ=arctan f'(x). This determines the approximate curve tangent direction corresponding to the target sampling point. This calculation method is essentially a finite difference method for approximate differentiation, which does not rely on the analytical expression of the curve. The smaller the sampling interval, the higher the accuracy of the tangent calculation. It can be adapted to electronic product film processing scenarios with different accuracy requirements. After obtaining the tangent direction of the curve, based on the planar geometric relationship that the tangent and the normal are perpendicular to each other, the direction angle of the corresponding curve normal is derived from the included angle θ of the tangent. The curve normal is the direction of the line connecting the blade tip and the center of the blade axis. Combining trigonometric functions, the ratio of the horizontal and vertical components of the normal direction can be further obtained, where the horizontal component corresponds to cosθ and the vertical component corresponds to sinθ. This direction parameter will be directly used as the direction basis for subsequent trajectory offset, ensuring that the line connecting the center of the blade axis and the blade tip is always perpendicular to the tangent of the curve during the cutting process. This matches the motion characteristics of the translational cutting head, making the blade orientation consistent with the direction of the cutting head's movement, and avoiding processing defects such as burrs and dragging deformation at the edge of the film material.

[0076] In one embodiment, for step S3, taking the sampling points on the target travel path of the cutting edge as a reference, offsetting along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, each sampling point is obtained as the corresponding center point of the cutting axis. Connecting all the center points of the cutting axis in the order of the sampling points generates the actual travel trajectory of the cutting axis center, wherein the center point of the cutting axis is located in front of the sampling point of the cutting edge along the travel direction, the step includes:

[0077] Select all sampling points along the target travel path of the blade tip in sequence, and determine the extension direction of the curve tangent line segment corresponding to each sampling point;

[0078] Using each sampling point on the target travel path of the cutting edge as a reference, move along the tangent line segment of the corresponding sampling point by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, and obtain the center point of the cutting axis corresponding to each sampling point.

[0079] Connect all the center points of the cutter axis in sequence according to the corresponding sampling points to generate a continuous actual travel trajectory of the cutter axis center.

[0080] In specific implementation, taking the sampling points on the target travel path of the cutting edge as the reference, the distance along the extension direction of the curve tangent line segment of the corresponding sampling point is offset by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, to obtain the center point of the cutting axis corresponding to each sampling point. The specific implementation process of generating the actual travel trajectory of the cutting axis center is as follows: This method is a general offset calculation scheme applicable to any continuous curve. All sampling points on the target travel path of the cutting edge are selected in sequence, and the angle θ between the pre-calculated curve tangent direction and the corresponding tangent is retrieved one by one. The fixed distance from the cutting edge to the center of the cutting axis is denoted as L. According to the plane trigonometric function relationship, the offset along the extension direction of the curve tangent line segment can be decomposed into a horizontal component and a vertical component, where the horizontal offset Δx = L・cosθ and the vertical offset Δy = L・sinθ. The target travel path of the cutting edge corresponds to the cutting edge trajectory curve f(x). The coordinates of any sampling point can be represented as (x, f(x)). After offsetting along the normal direction from this point, the corresponding cutting edge center point is obtained, with coordinates m and n satisfying m = x + Δx and n = f(x) + Δy, respectively. This completes the coordinate mapping transformation from the sampling point on the cutting edge trajectory curve f(x) to the corresponding point on the actual travel trajectory of the cutting edge center. Combining the correspondence between the tangent angle and the curve derivative θ = arctan f'(x), the offset can be further converted into an expression based on the curve derivative, where the lateral offset is... The vertical offset is The ratio of the two values ​​can be used to directly calculate the coordinate offset without solving for the angle separately.

[0081] For curves to be processed with a clear analytical function expression, the continuous function expression of the tool axis center trajectory is directly solved by establishing a point-to-point mapping relationship between the original curve and the tool axis trajectory. This generates a precise and continuous actual travel trajectory of the tool axis center, eliminating the need for discrete sampling and point connection steps. For discrete curves to be processed without an analytical expression, after completing the offset calculation of all sampling points, all tool axis center points are sequentially connected according to the processing sequence of the corresponding sampling points to form a continuous and smooth actual travel trajectory of the tool axis center. This universal solution can adapt to irregular curves of any shape. It can perform accurate trajectory offset calculations even for irregularly shaped electronic product protective films, fundamentally correcting the curve deviation caused by the tool tip offset spacing and ensuring that the tool tip always precisely conforms to the target curve during the cutting process.

[0082] Reference Figure 2 This is a schematic diagram illustrating the general form of the offset mapping between the tool tip trajectory and the tool axis center trajectory of the present invention. In the diagram, O is the origin of the Cartesian coordinate system, the x-axis is the horizontal coordinate axis, the y-axis is the vertical coordinate axis, and x0 is the abscissa corresponding to the tool tip tangent point P. The coordinate point sequence extracted in this step is the tool tip cutting trajectory, denoted as curve f(x); the actual driving object of the CNC equipment is the center point of the cutting tool axis, denoted as Q, and the motion trajectory of the tool axis center is denoted as g(x); the tool tip tangent point is denoted as P, and the fixed distance between point P and the center point Q of the tool axis is the tool offset constant L, that is, |PQ|=L always holds, and the line segment PQ is always tangent to f(x) at the tangent point P. Let the abscissa of any tangent point on the curve be x0, f'(x0) be the slope of the tangent line to f(x) at x0, and the tangent angle θ=arctan f'(x0). The horizontal offset Δx and the vertical offset can be obtained by trigonometric function conversion, thereby completing the mapping transformation from tool tip coordinates to tool axis coordinates.

[0083] In one embodiment, taking the sampling points on the target travel path of the cutting edge as a reference, offsetting them along the extension direction of the tangent segment of the curve by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, each sampling point is obtained as the corresponding center point of the cutting axis. Connecting all the center points of the cutting axis in the order of the sampling points generates the actual travel trajectory of the cutting axis center. The step of the center point of the cutting axis being located ahead of the sampling point of the cutting edge along the travel direction further includes:

[0084] If the target path of the blade tip is circular or arc-shaped, determine the center position and radius of the circular or arc-shaped curve;

[0085] Using the same center position as a reference, the radius of the tool axis center trajectory is determined by combining the fixed distance from the tool tip to the center of the tool axis;

[0086] Based on the determined center position and the radius of the tool axis center trajectory, the actual travel trajectory of the tool axis center is generated as a concentric circle with the travel path of the tool tip target.

[0087] In practical implementation, if the target path of the cutting edge is circular or arc-shaped, this scenario can be solved directly using a geometric simplification method, eliminating the need for point-by-point offset calculations and significantly improving computational efficiency. Specifically, the center position and radius of the circular or arc-shaped curve are determined, and the radius of the arc corresponding to the cutting edge trajectory is denoted as r, with the center at point O. Since the line connecting the cutting edge to the center of the cutting axis is always tangent to the arc, meaning this line is perpendicular to the radius of the arc, the center, the cutting edge, and the center of the cutting axis together form a right triangle. According to the Pythagorean theorem, the distance from the center of the circle to the center of the cutting axis is the radius R of the cutting axis center trajectory, satisfying the following relationship: Where L is the fixed distance from the blade tip to the center of the blade axis. Therefore, the trajectory of the blade axis center is a concentric circle with the original blade tip trajectory. By directly generating a corresponding circular or arc-shaped curve with the same center position and radius R, the actual trajectory of the blade axis center can be obtained. This calculation method is suitable for regular arc-shaped products such as circular lens films and flat films with rounded chamfers. The calculation process avoids errors caused by point-by-point approximation, resulting in higher trajectory smoothness. It also effectively reduces the computational load on the control system and is suitable for passive rotational cutting characteristics with blade tip offset and blade tilt. (Refer to...) Figure 3 This diagram illustrates the relationship between the circular curve blade tip trajectory and the blade center trajectory of this invention. In the diagram, P is the blade tip cutting point, Q is the corresponding blade axis center point, r is the radius of the circular blade tip trajectory, R is the radius of the circular blade center trajectory, and L is the blade offset constant. For commonly used basic curves in mobile phone film cutting, a simplified calculation method can be used: the g(x) corresponding to the straight curve is an equidistant straight line parallel to the original straight line with a spacing equal to L; the radius of the circular curve blade tip trajectory is r. Since PQ is always perpendicular to the blade tip radius, the line connecting the blade center and the center of the circle forms the hypotenuse of a right triangle. Therefore, the corresponding blade center trajectory g(x) is a concentric circle with a radius of r. .

[0088] In one embodiment, taking the sampling points on the target travel path of the cutting edge as a reference, offsetting them along the extension direction of the tangent segment of the curve by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, each sampling point is obtained as the corresponding center point of the cutting axis. Connecting all the center points of the cutting axis in the order of the sampling points generates the actual travel trajectory of the cutting axis center. The step of the center point of the cutting axis being located ahead of the sampling point of the cutting edge along the travel direction further includes:

[0089] If the target travel path of the tool tip is composed of straight segments and circular arc segments connected tangentially, distinguish between two connection sequences along the machining travel direction: straight segments connecting to circular arc segments and circular arc segments connecting to straight segments, and extract the curve parameters of the straight segments and circular arc segments respectively.

[0090] The straight line segment extending along the tangent is offset by a distance equal to the fixed distance from the tool tip to the center of the tool axis, thus obtaining the corresponding straight line trajectory segment of the tool axis center;

[0091] The arc segment is processed using a concentric circle offset method to obtain the corresponding central arc trajectory segment of the tool axis;

[0092] Calculate the corresponding transition correction angle based on the current connection sequence, and determine the coordinates of the connection point between the straight trajectory segment and the circular trajectory segment of the tool axis center based on the transition correction angle, so that the two trajectories are tangent to each other at the connection point, generating a complete actual travel trajectory of the tool axis center.

[0093] In practical implementation, if the target travel path of the tool tip consists of a straight line segment and a circular arc segment connected tangentially, the connection order is first determined along the machining direction, using the connection point of the two curves as the boundary: if the first segment is a straight line segment and the second segment is a circular arc segment, it is determined as a straight line segment connecting to a circular arc segment; if the first segment is a circular arc segment and the second segment is a straight line segment connecting to a circular arc segment. There is no strict order for either connection order; both are processed using a unified segmented offset + corner matching logic. After extracting the direction parameters of the straight line segment and the center position and radius parameters of the circular arc segment, the straight line segment is offset along the tangential extension direction by a distance equal to the fixed distance from the tool tip to the tool axis center, yielding the corresponding tool axis center straight line trajectory segment. The circular arc segment is processed using a concentric circle offset method, referring to the calculation logic of a circular trajectory, to obtain the tool axis center circular arc trajectory segment with radius R, where R satisfies the following relationship... r is the radius of the arc segment of the cutting tip, and L is the fixed distance from the cutting tip to the center of the cutting axis.

[0094] The corresponding transition correction angle θ is calculated based on the current connection sequence. θ is offset from the connection angle θ, satisfying the relationship θ=arctan (r / L). The application direction of the transition correction angle is opposite for the two connection sequences: in the straight-to-arc scenario, the angle deflects along the center of the arc; in the arc-to-straight scenario, the angle deflects along the extension direction of the straight line. The endpoint positions of the two offset trajectories are adjusted according to the transition correction angle to determine the coordinates of the connection point. This ensures that the straight trajectory segment of the cutter axis center and the arc trajectory segment of the cutter axis center are tangent at the connection point, ultimately splicing together a complete and continuous actual travel trajectory of the cutter axis center. This method is suitable for mainstream products such as conventional rectangular screen protectors with rounded corners, such as mobile phone and tablet screen protectors. The transition between straight edges and rounded corners is smooth and without breaks, ensuring a natural edge transition after cutting, without sharp corners or steps, meeting the appearance and dimensional accuracy requirements of electronic product protective films. (Refer to...) Figure 4 This is a schematic diagram of the tool center trajectory for the transition curve from a straight line to an arc according to the present invention. In the diagram, AB is the trajectory of the straight line segment of the tool tip, BC is the trajectory of the arc segment of the tool tip, and B is the connection point between the straight line and the arc; A'B' is the trajectory of the straight line segment of the tool center, B'C' is the trajectory of the arc segment of the tool center, and B' is the transition connection point of the tool center trajectory; r is the radius of the arc segment of the tool tip, R is the radius of the arc segment of the tool center, L is the tool offset constant, and θ is the transition correction angle. The transition angle satisfies θ=arctan (r / L). Through this correction angle, the smooth connection between the straight line segment and the arc segment of the tool center trajectory is achieved, eliminating the feed inflection point.

[0095] Similarly, the tool center trajectory is obtained using a segmented splicing method. The arc segment of the tool center rotates less by an angle θ compared to the arc segment of the tool tip, ensuring a smooth, inflection-free transition between the arc segment and the straight segment. The transition angle also satisfies θ = arctan(r / L). (Refer to...) Figure 5 This is a schematic diagram of the tool center trajectory of the transition curve from arc to straight line in this invention. In the figure, AB is the trajectory of the arc segment of the tool tip, BC is the trajectory of the straight segment of the tool tip, and B is the connection point between the arc and the straight line; A'B' is the trajectory of the arc segment of the tool center, B'C' is the trajectory of the straight segment of the tool center, and B' is the transition connection point of the tool center trajectory; r is the radius of the arc of the tool tip, R is the radius of the arc of the tool center, L is the tool deviation constant, and θ is the transition correction angle. The correction angle is used to eliminate the sharp corner of the tool path splicing and ensure smooth cutting feed.

[0096] In one embodiment, step S4, controlling the center of the cutter shaft to translate along the actual travel trajectory of the cutter shaft center, the center of the cutter shaft center continuously moving along the actual travel trajectory of the cutter shaft center, the line connecting the cutter tip and the center of the cutter shaft always being tangent to the target travel path of the cutter tip, and the step of the cutter tip performing cutting processing according to the curve to be processed, includes:

[0097] Set the entry point at the starting position of the target travel path of the tool tip, generate an entry lead line that extends from the outside of the curve to the entry point and is tangent to the curve, and generate the corresponding tool axis offset trajectory of the entry lead line.

[0098] Set the exit point at the end of the target travel path of the tool tip, generate an exit lead line that extends from the exit point to the outside of the curve and is tangent to the curve, and generate the corresponding tool axis offset trajectory of the exit lead line.

[0099] The control tool axis center moves along the tool axis offset trajectory of the tool entry line to the tool entry position, and then performs the main curve cutting along the actual travel trajectory of the tool axis center. The workpiece is then moved out along the tool axis offset trajectory of the tool exit line to complete the complete curve cutting process.

[0100] Reference Figure 6 This is a schematic diagram of the cutting path of a blade tip-off type translational cutting head in one embodiment of the present invention. In specific implementations, considering the high requirements for cut smoothness and edge integrity of protective films for electronic products such as mobile phone screen protectors and tablet screen protectors, this embodiment adds tangential entry and exit control to the main curved cutting, avoiding cut indentations and film edge tearing caused by direct vertical cutting. (Refer to...) Figure 7The present invention relates to a blade tip offset translational cutting head structure. In this structure, the blade tip is offset from the feed center axis, which serves only as the reference for blade head displacement. If the feed center axis is set as the rotation reference to adjust the blade orientation, the blade tip will undergo radial arc displacement with rotation, causing the blade landing point to drift and the subsequent cutting position to deviate from the target curve. Therefore, the present invention controls the overall translation of the blade head throughout the cutting process, using the blade tip as the sole rotation reference. Before and after blade orientation adjustment, the blade tip position always coincides with the preset landing point, ensuring curve cutting accuracy. First, set the entry point at the starting position of the target travel path of the cutting tip, coinciding with the starting endpoint of the main curve. Generate an entry guide line, with one end of the entry guide line located outside the curve to be processed and the other end extending to the entry point. The entry guide line is tangent to the target travel path of the cutting tip at the entry point, allowing the cutting edge to smoothly cut into the workpiece surface along the tangential direction, eliminating obvious cut marks caused by vertical cutting. Referring to the trajectory offset rules of the main curve, offset the entry guide line along its tangential line segment extension direction by a distance equal to the fixed distance from the cutting tip to the center of the cutting axis, and generate the corresponding cutting axis offset trajectory of the entry guide line. This ensures that the positional constraint relationship between the cutting tip and the center of the cutting axis is completely consistent with the main cutting segment during the cutting process, avoiding abrupt changes in trajectory at the connection position. Correspondingly, an exit point is set at the end of the target travel path of the cutting tip, coinciding with the end point of the main curve. An exit guide line is generated extending from the exit point to the external cutting point of the curve. This exit guide line remains tangent to the target travel path of the cutting tip at the exit point, ensuring that the cutting edge can smoothly move out of the workpiece along the tangential direction after completing the main cut, avoiding defects such as film tailing and edge burrs during the retraction stage. Similarly, a tool axis offset trajectory for the exit guide line is generated according to a unified tangential segment extension direction offset rule, ensuring that the offset reference of the exit segment and the main segment is completely consistent. During actual cutting control, the CNC system first controls the tool axis center to smoothly move along the tool axis offset trajectory of the entry guide line to the entry position, completing the workpiece entry action. Then, it controls the tool axis center to continuously move along the pre-calculated actual travel trajectory of the tool axis center, completing the cutting of the main curve. Finally, it controls the tool axis center to smoothly move out of the workpiece surface along the tool axis offset trajectory of the exit guide line, completing the complete curve cutting process. Throughout the entire processing, the cutting head maintains a continuous translational motion, with the blade orientation aligned with the head's direction of travel. The cutter axis trajectory is continuous, smooth, and without inflection points in the entry, main body, and exit sections, ensuring uniform and flat cuts along the entire curve of the electronic product film, with no obvious entry or exit marks on the edges. This effectively improves the product's processing yield and appearance quality.

[0101] Reference Figure 8 Here is a structural block diagram of a tool axis trajectory correction control device for CNC curve cutting according to an embodiment of the present invention, comprising:

[0102] The data acquisition module is used to acquire the curve data of the curve to be processed and to determine the curve to be processed as the target travel path of the tool tip;

[0103] The direction determination module is used to select reference points, construct a geometric figure by combining the sampling points on the target travel path of the cutting tip, calculate the tangent direction of the curve corresponding to the sampling point through the geometric figure, and take the sampling point as the tangent point, and take the fixed distance line segment from the cutting tip to the center of the cutting axis as the tangent line segment of the curve.

[0104] The trajectory generation module is used to take the sampling points on the target travel path of the cutting tip as a reference, offset along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting tip to the center of the cutting axis, to obtain the corresponding cutting axis center point of each sampling point, and connect all the cutting axis center points in the order of sampling points to generate the actual travel trajectory of the cutting axis center. The cutting axis center point is located in front of the cutting tip sampling point along the tangent line of the curve.

[0105] The path cutting module is used to control the center of the cutter shaft to translate along the actual travel trajectory of the cutter shaft center. The center of the cutter shaft center moves continuously along the actual travel trajectory of the cutter shaft center. The line connecting the cutter tip and the center of the cutter shaft is always tangent to the target travel path of the cutter tip. The cutter tip performs cutting processing according to the curve to be processed.

[0106] For the specific implementation of each module in the above device example, please refer to the above method embodiments, which will not be repeated here.

[0107] Reference Figure 9 This invention also provides a computer device, which can be a server, and its internal structure can be as follows: Figure 9 As shown, the computer device includes a processor, memory, display screen, input device, network interface, and database connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system, computer programs, and database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The database stores the data corresponding to this embodiment. The network interface is used to communicate with external terminals via a network connection. When the computer program is executed by the processor, it implements the above-described method.

[0108] Those skilled in the art will understand that Figure 9 The structures shown are merely block diagrams of some structures related to the present invention and do not constitute a limitation on the computer devices on which the present invention is applied.

[0109] An embodiment of the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-described method. It is understood that the computer-readable storage medium in this embodiment can be a volatile readable storage medium or a non-volatile readable storage medium.

[0110] In summary, this invention obtains the curve data of the curve to be processed and determines the curve as the target travel path of the tool tip; selects reference points and constructs a geometric figure by combining the sampling points on the target travel path of the tool tip; calculates the tangent direction of the curve corresponding to the sampling points through the geometric figure; takes the sampling points as the tangent points and takes the fixed-distance line segment from the tool tip to the center of the tool axis as the tangent line segment of the curve; taking the sampling points on the target travel path of the tool tip as the reference, offsets along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the tool tip to the center of the tool axis, obtaining each sampling point as the corresponding center point of the tool axis; and so on. The sampling points are sequentially connected to all the center points of the cutter axis to generate the actual travel trajectory of the cutter axis center. The center point of the cutter axis is located in front of the tangent of the curve along which the sampling point of the cutter tip travels. The cutter axis center is controlled to translate along the actual travel trajectory of the cutter axis center. The cutter axis center moves continuously along the actual travel trajectory of the cutter axis center. The line connecting the cutter tip and the center of the cutter axis is always tangent to the target travel path of the cutter tip. The cutter tip performs cutting processing according to the curve to be processed, so as to achieve the purpose of correcting the fixed offset distance between the cutter tip and the center of the cutter axis, eliminating curve cutting deformation, improving the cutting accuracy of the curve edge of electronic product film and the yield of finished product appearance.

[0111] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the present invention and embodiments can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual-rate SDRAM (SSRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM, etc.

[0112] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, apparatus, article, or method that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, apparatus, article, or method. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, apparatus, article, or method that includes that element.

[0113] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for correcting and controlling the tool axis trajectory in CNC curve cutting, characterized in that, Includes the following steps: Obtain the curve data of the curve to be processed, and determine the curve to be processed as the target travel path of the tool tip; Select reference points and construct a geometric figure by combining the sampling points on the target travel path of the cutting tip. Calculate the tangent direction of the curve corresponding to the sampling points through the geometric figure. Using the sampling points as the tangent points, take the fixed-distance line segment from the cutting tip to the center of the cutting axis as the tangent line segment of the curve. Using the sampling points on the target travel path of the cutting tip as a reference, offset along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting tip to the center of the cutting axis, each sampling point is obtained as the corresponding center point of the cutting axis. All the center points of the cutting axis are connected in the order of the sampling points to generate the actual travel trajectory of the center of the cutting axis. The center point of the cutting axis is located in front of the tangent line of the cutting tip sampling point along the curve. The control tool axis center moves along the actual travel trajectory of the tool axis center. The tool axis center moves continuously along the actual travel trajectory of the tool axis center. The line connecting the tool tip and the tool axis center is always tangent to the target travel path of the tool tip. The tool tip performs cutting processing according to the curve to be processed.

2. The tool axis trajectory correction control method for CNC curve cutting according to claim 1, characterized in that, The step of acquiring the curve data of the curve to be processed and determining the curve to be processed as the target travel path of the tool tip includes: Identify the geometric type of the curve to be processed; If the curve to be processed is a discrete curve without an analytical expression, collect data from multiple discrete sampling points on the curve to be processed, perform continuous curve fitting on the multiple discrete sampling points to generate a smooth and continuous curve to be processed, and determine the smooth and continuous curve to be processed generated by fitting as the target travel path of the tool tip. If the curve to be processed has an analytical function expression, the corresponding analytical function expression is directly retrieved to generate a continuous curve to be processed and determine it as the target travel path of the tool tip.

3. The tool axis trajectory correction control method for CNC curve cutting according to claim 1, characterized in that, The steps of selecting reference points, constructing a geometric figure by combining the sampling points on the target travel path of the cutting edge, calculating the tangent direction of the curve corresponding to the sampling points through the geometric figure, and taking the sampling points as the tangent points, and using the fixed-distance line segment from the cutting edge to the center of the cutting axis as the tangent line segment of the curve, include: Select a reference point outside the target's travel path; Connect the reference points with two adjacent sets of sampling points on the path of the blade tip target to form a closed polygon. Calculate the approximate tangent direction corresponding to the sampling point based on the positional relationship of each side of the closed polygon; Using the current sampling point as the tangent point, extend the line segment with a length equal to the fixed distance from the tip of the tool to the center of the tool axis along the tangent direction to obtain the tangent line segment from the tip of the tool to the center of the tool axis.

4. The tool axis trajectory correction control method for CNC curve cutting according to claim 1, characterized in that, The step of using the sampling points on the target travel path of the cutting edge as a reference, offsetting along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, to obtain the corresponding cutting axis center point for each sampling point, and connecting all the cutting axis center points in the order of the sampling points to generate the actual travel trajectory of the cutting axis center, wherein the cutting axis center point is located in front of the sampling point of the cutting edge along the travel direction, includes: Select all sampling points along the target travel path of the blade tip in sequence, and determine the extension direction of the curve tangent line segment corresponding to each sampling point; Using each sampling point on the target travel path of the cutting edge as a reference, move along the tangent line segment of the corresponding sampling point by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, and obtain the center point of the cutting axis corresponding to each sampling point. Connect all the center points of the cutter axis in sequence according to the corresponding sampling points to generate a continuous actual travel trajectory of the cutter axis center.

5. The tool axis trajectory correction control method for CNC curve cutting according to claim 1, characterized in that, The step of using the sampling points on the target travel path of the cutting edge as a reference, offsetting along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, to obtain the corresponding cutting axis center point for each sampling point, and connecting all the cutting axis center points in the order of the sampling points to generate the actual travel trajectory of the cutting axis center, wherein the cutting axis center point is located in front of the sampling point of the cutting edge along the travel direction, further includes: If the target path of the blade tip is circular or arc-shaped, determine the center position and radius of the circular or arc-shaped curve; Using the same center position as a reference, the radius of the tool axis center trajectory is determined by combining the fixed distance from the tool tip to the center of the tool axis; Based on the determined center position and the radius of the tool axis center trajectory, the actual travel trajectory of the tool axis center is generated as a concentric circle with the travel path of the tool tip target.

6. The tool axis trajectory correction control method for CNC curve cutting according to claim 1, characterized in that, The step of using the sampling points on the target travel path of the cutting edge as a reference, offsetting along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting edge to the center of the cutting axis, to obtain the corresponding cutting axis center point for each sampling point, and connecting all the cutting axis center points in the order of the sampling points to generate the actual travel trajectory of the cutting axis center, wherein the cutting axis center point is located in front of the sampling point of the cutting edge along the travel direction, further includes: If the target travel path of the tool tip is composed of straight segments and circular arc segments connected tangentially, distinguish between two connection sequences along the machining travel direction: straight segments connecting to circular arc segments and circular arc segments connecting to straight segments, and extract the curve parameters of the straight segments and circular arc segments respectively. The straight line segment extending along the tangent is offset by a distance equal to the fixed distance from the tool tip to the center of the tool axis, thus obtaining the corresponding straight line trajectory segment of the tool axis center; The arc segment is processed using a concentric circle offset method to obtain the corresponding arc trajectory segment of the tool axis center; Calculate the corresponding transition correction angle based on the current connection sequence, and determine the coordinates of the connection point between the straight trajectory segment and the circular trajectory segment of the tool axis center based on the transition correction angle, so that the two trajectories are tangent to each other at the connection point, generating a complete actual travel trajectory of the tool axis center.

7. The tool axis trajectory correction control method for CNC curve cutting according to claim 1, characterized in that, The steps of controlling the tool axis center to translate along the actual travel trajectory of the tool axis center, the tool axis center continuously moving along the actual travel trajectory of the tool axis center, the line connecting the tool tip and the tool axis center always being tangent to the target travel path of the tool tip, and the tool tip performing cutting processing according to the curve to be processed include: Set the entry point at the starting position of the target travel path of the tool tip, generate an entry lead line that extends from the outside of the curve to the entry point and is tangent to the curve, and generate the corresponding tool axis offset trajectory of the entry lead line. Set the exit point at the end of the target travel path of the tool tip, generate an exit lead line that extends from the exit point to the outside of the curve and is tangent to the curve, and generate the corresponding tool axis offset trajectory of the exit lead line. The control tool axis center moves along the tool axis offset trajectory of the tool entry line to the tool entry position, and then performs the main curve cutting along the actual travel trajectory of the tool axis center. The workpiece is then moved out along the tool axis offset trajectory of the tool exit line to complete the complete curve cutting process.

8. A tool axis trajectory correction control device for CNC curve cutting, characterized in that, include: The data acquisition module is used to acquire the curve data of the curve to be processed and to determine the curve to be processed as the target travel path of the tool tip; The direction determination module is used to select reference points, construct a geometric figure by combining the sampling points on the target travel path of the cutting tip, calculate the tangent direction of the curve corresponding to the sampling point through the geometric figure, and take the sampling point as the tangent point, and take the fixed distance line segment from the cutting tip to the center of the cutting axis as the tangent line segment of the curve. The trajectory generation module is used to take the sampling points on the target travel path of the cutting tip as a reference, offset along the extension direction of the tangent line segment of the curve by a distance equal to the fixed distance from the cutting tip to the center of the cutting axis, to obtain the corresponding cutting axis center point of each sampling point, and connect all the cutting axis center points in the order of sampling points to generate the actual travel trajectory of the cutting axis center. The cutting axis center point is located in front of the cutting tip sampling point along the tangent line of the curve. The path cutting module is used to control the center of the cutter shaft to translate along the actual travel trajectory of the cutter shaft center. The center of the cutter shaft center moves continuously along the actual travel trajectory of the cutter shaft center. The line connecting the cutter tip and the center of the cutter shaft is always tangent to the target travel path of the cutter tip. The cutter tip performs cutting processing according to the curve to be processed.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the tool axis trajectory correction control method for CNC curve cutting as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the tool axis trajectory correction control method for CNC curve cutting as described in any one of claims 1 to 7.

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