Track fitting method and device, processing equipment and readable storage medium

Abstract

The invention relates to a track fitting method and device, machining equipment and a readable storage medium. The method comprises the steps that a contour error constraint value, a track starting point, a track ending point and a to-be-fitted point set interval of a machining track are obtained; according to the contour error constraint value, the trajectory starting point, the trajectory ending point and the to-be-fitted point set interval, elliptic arc fitting information of the multiple linear sub-processing trajectories is determined; and according to the elliptic arc fitting information, a machining fitting elliptic arc of the machining track is determined. According to the method, the continuity of the speed and the acceleration of all positions of the machining track is guaranteed, the problem of abnormal vibration of a machine tool caused by non-uniform track curvature changes of all positions of the machining track is solved, continuous and uninterrupted machining of a plurality of machining fitting elliptic arcs in the machining track of a large-format part is achieved, and the laser machining efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the field of laser processing, and in particular, to a trajectory fitting method, device, processing equipment and readable storage medium. Background Art

[0002] With the continuous development of laser processing technology and the continuous enrichment of laser requirements, the requirements for laser processing are getting higher and higher. When processing complex parts by laser, in order to fit curves or surfaces similar to elliptical arcs, multiple continuous straight line segments are usually used for approximation, that is, multiple continuous linear sub-processing trajectories are formed. However, the trajectory curvature at the tangent corners formed by adjacent straight line segments will fluctuate greatly, which will cause abnormal vibration of the machine tool and thus seriously affect the laser processing efficiency.

[0003] A common high-speed processing method for continuous straight line segments is to insert a transition spline curve between adjacent straight line segments. However, the cyclic appearance of multiple straight line segments and transition spline curves during interpolation leads to fluctuations in the processing speed. Summary of the Invention

[0004] Based on this, in view of the above technical problems, it is necessary to provide a trajectory fitting method, device, processing equipment and readable storage medium.

[0005] A trajectory fitting method is applied to a processing trajectory including multiple linear sub-processing trajectories, and includes:

[0006] Obtain the contour error constraint value, the starting point of the trajectory, the ending point of the trajectory, and the fitting point set interval of the processing trajectory;

[0007] Determine the elliptical arc fitting information of multiple linear sub-processing trajectories according to the contour error constraint value, the starting point of the trajectory, the ending point of the trajectory, and the fitting point set interval;

[0008] Determine the processed fitting elliptical arc of the processing trajectory according to the elliptical arc fitting information.

[0009] In one embodiment, the determining the elliptical arc fitting information of multiple linear sub-processing trajectories according to the contour error constraint value, the starting point of the trajectory, the ending point of the trajectory, and the fitting point set interval includes:

[0010] Obtain the number of fitting points in the fitting point set interval;

[0011] Determine the elliptical fitting points of multiple linear sub-processing trajectories according to the starting point and the ending point of the trajectory. The elliptical fitting points are fitting points that pass through the processed fitting elliptical arc and do not coincide with the starting point and the ending point of the trajectory;

[0012] Determine the elliptical arc fitting information of multiple linear sub - processing trajectories according to the contour error constraint value, the number of fitting points, the starting point of the trajectory, the ending point of the trajectory, the elliptical fitting points, and the interval of the set of points to be fitted.

[0013] In one embodiment, the step of determining the elliptical arc fitting information of multiple linear sub - processing trajectories according to the contour error constraint value, the number of fitting points, the starting point of the trajectory, the ending point of the trajectory, the elliptical fitting points, and the interval of the set of points to be fitted includes:

[0014] Determine the elliptical arc coefficient formula according to the number of fitting points, the starting point of the trajectory, the ending point of the trajectory, and the elliptical arc construction equation;

[0015] Determine the process - simplified variables according to the starting point of the trajectory, the ending point of the trajectory, and the elliptical fitting points;

[0016] Determine the simplified elliptical arc coefficient formula according to the elliptical arc construction equation, the elliptical arc coefficient formula, and the process - simplified variables;

[0017] Determine the elliptical arc fitting information of multiple linear sub - processing trajectories according to the contour error constraint value, the simplified elliptical arc coefficient formula, and the interval of the set of points to be fitted.

[0018] In one embodiment, the step of determining the process - simplified variables according to the starting point of the trajectory, the ending point of the trajectory, and the elliptical fitting points includes:

[0019] Determine the first process - simplified variable according to the vertical axis coordinates of both the starting point and the ending point of the trajectory;

[0020] Determine the second process - simplified variable according to the first process - simplified variable and the elliptical fitting points;

[0021] The step of determining the simplified elliptical arc coefficient formula according to the elliptical arc construction equation, the elliptical arc coefficient formula, and the process - simplified variables includes:

[0022] Determine the simplified elliptical arc construction equation according to the elliptical arc construction equation, the elliptical arc coefficient formula, and the first process - simplified variable;

[0023] Determine the simplified elliptical arc coefficient formula according to the simplified elliptical arc construction equation and the second process - simplified variable;

[0024] The step of determining the elliptical arc fitting information of multiple linear sub - processing trajectories according to the contour error constraint value, the simplified elliptical arc coefficient formula, and the interval of the set of points to be fitted includes:

[0025] Determine the initial elliptical arc fitting coefficients according to the simplified formula of the elliptical arc coefficients and the interval of the point set to be fitted;

[0026] Determine the elliptical arc fitting error value according to the initial elliptical arc fitting coefficients;

[0027] Determine the elliptical arc fitting information according to the initial elliptical arc fitting coefficients, the elliptical arc fitting error value and the profile error constraint value;

[0028] In one embodiment, the obtaining the profile error constraint value, the trajectory start point, the trajectory end point and the interval of the point set to be fitted of the machining trajectory includes:

[0029] Obtain the profile error constraint value, the trajectory start point, the trajectory end point and the angular deflection amount of adjacent linear sub-machining trajectories of the machining trajectory;

[0030] Determine the intervals of the point sets to be fitted of multiple linear sub-machining trajectories according to the profile error constraint value, the trajectory start point, the trajectory end point and the angular deflection amount;

[0031] In one embodiment, the determining the elliptical arc fitting information of multiple linear sub-machining trajectories according to the profile error constraint value, the trajectory start point, the trajectory end point and the interval of the point set to be fitted includes:

[0032] Determine the initial elliptical arc fitting point sets of multiple linear sub-machining trajectories according to the trajectory start point, the trajectory end point and the angular deflection amount;

[0033] Determine the interval of the point set to be fitted according to the profile error constraint value and the initial elliptical arc fitting point sets;

[0034] In one embodiment, the determining the machining fitting elliptical arc of the machining trajectory according to the elliptical arc fitting information includes:

[0035] Determine the elliptical arc length value within a unit period according to the elliptical arc fitting information;

[0036] Determine the machining interpolation position of the machining trajectory according to the elliptical arc length value;

[0037] Determine the machining fitting elliptical arc according to the machining interpolation position;

[0038] A trajectory fitting device, applied to a machining trajectory including multiple linear sub-machining trajectories, includes:

[0039] An acquisition module, configured to acquire the profile error constraint value, the trajectory start point, the trajectory end point and the interval of the point set to be fitted of the machining trajectory;

[0040] A fitting information determination module, connected to the acquisition module, for determining elliptical arc fitting information of a plurality of the linear sub-machining trajectories according to the contour error constraint value, the trajectory starting point, the trajectory ending point and the interval of the point set to be fitted;

[0041] The processing module is connected to the fitting information determination module and is used to determine the processing fitting elliptical arc of the processing trajectory according to the elliptical arc fitting information.

[0042] A processing device includes a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the above method.

[0043] A computer-readable storage medium stores a computer program, which implements the above method when executed by a processor.

[0044] A computer program product, when the computer program product is run on a terminal device, enables the terminal device to execute any of the methods described above.

[0045] The beneficial effects of the embodiments provided in this application include:

[0046] The trajectory fitting method determines the elliptical arc fitting information of multiple linear sub-processing trajectories according to the contour error constraint value of the processing trajectory, the trajectory starting point, the trajectory ending point and the interval of the point set to be fitted, and fits the processing fitting elliptical arc that meets the contour error constraint value of the processing trajectory and passes through the trajectory starting point and the trajectory ending point and is suitable for the processing trajectory with multiple linear sub-processing trajectories according to the obtained elliptical arc fitting information. Compared with the initial processing trajectory, the method can effectively improve the trajectory smoothness at the connection point of adjacent linear sub-processing trajectories in the processing trajectory while meeting the processing accuracy constraint of the processing trajectory, thereby maintaining a large feed speed at the connection point of adjacent linear sub-processing trajectories, ensuring the continuity of speed and acceleration at various locations of the processing trajectory, improving the problem of abnormal vibration of the machine tool caused by uneven change of trajectory curvature at various locations of the processing trajectory, and realizing continuous and uninterrupted processing of multiple processing fitting elliptical arcs in the processing trajectory of large-format parts, which can improve the laser processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1It is a schematic flowchart of a trajectory fitting method in an embodiment;

[0049] Figure 2 It is a specific flowchart of step 104 in an embodiment;

[0050] Figure 3 It is a specific flowchart of step 102 in an embodiment;

[0051] Figure 4 It is a specific flowchart of step 106 in an embodiment;

[0052] Figure 5 It is a schematic diagram of a trajectory fitting process in an embodiment;

[0053] Figure 6 It is a schematic diagram of the structure for machining a fitted elliptical arc in an embodiment;

[0054] Figure 7 It is a schematic block diagram of the structure of a trajectory fitting device in an embodiment;

[0055] Figure 8 It is a specific schematic block diagram of the fitting information determination module 40 in an embodiment;

[0056] Figure 9 It is a specific schematic block diagram of the acquisition module 20 in an embodiment;

[0057] Figure 10 It is a specific schematic block diagram of the machining module 60 in an embodiment;

[0058] Figure 11 It is a schematic diagram of the structure of a machining device in an embodiment. Specific Embodiments

[0059] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application 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 only used to explain the present application and are not used to limit the present application.

[0060] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality of" means two or more unless otherwise specifically defined.

[0061] Figure 1 , It is a schematic flowchart of a trajectory fitting method in an embodiment.

[0062] In this embodiment, as Figure 1 shown, the trajectory fitting method is applied to a machining trajectory including a plurality of linear sub-machining trajectories, and the trajectory fitting method includes steps 102 to 106.

[0063] Step 102, obtaining a contour error constraint value, a trajectory start point, a trajectory end point, and a point set interval to be fitted of the machining trajectory.

[0064] The machining trajectory can be an initial planning trajectory for laser machining of a component or an initial planning trajectory for machining. The linear sub-machining trajectory can be a linear segmented initial planning trajectory that constitutes the machining trajectory. The contour error constraint value can be an extreme value of the fitting accuracy allowed for the elliptical arc fitting of the machining trajectory. The trajectory start point can be the starting end point of the machining trajectory. The trajectory end point can be the ending end point of the machining trajectory. The point set interval to be fitted can be a point set for performing elliptical arc fitting on the machining trajectory.

[0065] Optionally, the contour error constraint value includes a maximum contour error and a minimum contour error. The maximum contour error can be the maximum fitting accuracy allowed for the elliptical arc fitting of the machining trajectory, and can be specifically applied to scenarios where the maximum fitting accuracy is restricted; the minimum contour error can be the minimum fitting accuracy allowed for the elliptical arc fitting of the machining trajectory, and can be specifically applied to scenarios where the minimum fitting accuracy is restricted. The point set interval to be fitted can be a point set composed of the trajectory end points of a plurality of linear sub-machining trajectories.

[0066] The situations of obtaining the contour error constraint value, the trajectory start point, the trajectory end point, and the point set interval to be fitted of the machining trajectory include: analyzing the machining trajectory to obtain the contour error constraint value, the trajectory start point, and the trajectory end point of the machining trajectory, and roughly dividing a plurality of sub-machining trajectories in the machining trajectory, and then obtaining the point set interval to be fitted of the machining trajectory.

[0067] Step 104, determining elliptical arc fitting information of a plurality of linear sub-machining trajectories according to the contour error constraint value, the trajectory start point, the trajectory end point, and the point set interval to be fitted.

[0068] The elliptical arc fitting information can be information formed based on the contour error constraint value, the trajectory start point, the trajectory end point, and the point set interval to be fitted, and can be used to guide the elliptical arc fitting process of the machining trajectory. Optionally, the elliptical arc fitting information can be coefficients for constructing the elliptical arc corresponding to the machining trajectory.

[0069] The situations for determining the elliptical arc fitting information of multiple linear sub - machining trajectories according to the contour error constraint value, the starting point of the trajectory, the ending point of the trajectory, and the interval of the set of points to be fitted include: obtaining the number of fitting points in the interval of the set of points to be fitted; determining the elliptical fitting points of multiple linear sub - machining trajectories according to the starting point and the ending point of the trajectory; and determining the elliptical arc fitting information of multiple linear sub - machining trajectories according to the contour error constraint value, the number of fitting points, the starting point of the trajectory, the ending point of the trajectory, the elliptical fitting points, and the interval of the set of points to be fitted.

[0070] The number of fitting points can be the number of trajectory end - points of multiple linear sub - machining trajectories used for elliptical arc fitting of the machining trajectory. The elliptical fitting points can be the fitting points that pass through the machined fitting elliptical arc and do not coincide with the starting point and the ending point of the trajectory.

[0071] It should be noted that when performing elliptical arc fitting on the machining trajectory, the number of fitting points in the interval of the set of points to be fitted must be greater than a certain number to obtain the elliptical coefficients required for fitting a complete ellipse, and then the machined fitting elliptical arc of the machining trajectory can be obtained.

[0072] Step 106: Determine the machined fitting elliptical arc of the machining trajectory according to the elliptical arc fitting information.

[0073] The machined fitting elliptical arc can be formed based on the elliptical arc fitting information and can guide the actual machining process of the machining trajectory.

[0074] The situations for determining the machined fitting elliptical arc of the machining trajectory according to the elliptical arc fitting information include: determining the interpolation information of the machining trajectory according to the elliptical arc fitting information; and determining the machined fitting elliptical arc of the machining trajectory according to the elliptical arc fitting information and the interpolation information.

[0075] During the fitting process of the machining trajectory of the component, first, analyze the machining trajectory to obtain the contour error constraint value, the starting point and the ending point of the trajectory, and roughly divide multiple sub - machining trajectories in the machining trajectory, and then obtain the interval of the set of points to be fitted on the machining trajectory; secondly, obtain the number of fitting points in the interval of the set of points to be fitted; determine the elliptical fitting points of multiple linear sub - machining trajectories according to the starting point and the ending point of the trajectory; determine the elliptical arc fitting information of multiple linear sub - machining trajectories according to the contour error constraint value, the number of fitting points, the starting point of the trajectory, the ending point of the trajectory, the elliptical fitting points, and the interval of the set of points to be fitted; then determine the interpolation information of the machining trajectory according to the elliptical arc fitting information; and determine the machined fitting elliptical arc of the machining trajectory according to the elliptical arc fitting information and the interpolation information.

[0076] The trajectory fitting method provided in this embodiment determines the elliptical arc fitting information of multiple linear sub-processing trajectories according to the contour error constraint value of the processing trajectory, the starting point of the trajectory, the ending point of the trajectory, and the interval of the point set to be fitted. Then, based on the obtained elliptical arc fitting information, a processing fitting elliptical arc that meets the contour error constraint value of the processing trajectory, passes through the starting point and the ending point of the trajectory, and is applicable to the processing trajectory with multiple linear sub-processing trajectories is fitted. Compared with the initial processing trajectory, it can effectively improve the smoothness of the trajectory at the connection of adjacent linear sub-processing trajectories while meeting the processing accuracy constraint of the processing trajectory, thereby maintaining a large feed rate at the connection of adjacent linear sub-processing trajectories, ensuring the continuity of the speed and acceleration at all parts of the processing trajectory, and improving the problem of abnormal vibration of the machine tool caused by uneven changes in the trajectory curvature at all parts of the processing trajectory. It also realizes the continuous and uninterrupted processing of multiple processing fitting elliptical arcs in the processing trajectory of large-format parts, and can improve the laser processing efficiency.

[0077] Figure 2 is a schematic flow diagram of step 104 in an embodiment.

[0078] In this embodiment, as Figure 2 shown, this step 104 includes sub-steps 202 to sub-step 208.

[0079] In sub-step 202, according to the number of fitting points, the starting point of the trajectory, the ending point of the trajectory, and the elliptical arc construction equation, the elliptical arc coefficient formula is determined.

[0080] The elliptical arc construction equation can be the construction equation required for elliptical arc fitting of the processing trajectory. The elliptical arc coefficient formula can be an expression formed based on the number of fitting points, the starting point of the trajectory, the ending point of the trajectory, and the elliptical arc construction equation, which can reflect the correlation relationship between the constituent coefficients in the elliptical arc construction equation. Optionally, the elliptical arc construction equation can be the general coefficient equation of the ellipse.

[0081] In sub-step 204, according to the starting point of the trajectory, the ending point of the trajectory, and the elliptical fitting points, the process simplification variables are determined.

[0082] The process simplification variables can be variables formed based on the starting point of the trajectory, the ending point of the trajectory, and the elliptical fitting points, which can simplify the elliptical arc coefficient formula. Optionally, the process simplification variables include the first process simplification variable and the second process simplification variable.

[0083] Determining the process simplification variables according to the starting point of the trajectory, the ending point of the trajectory, and the elliptical fitting points includes: determining the first process simplification variable according to the vertical axis coordinates of the starting point and the ending point of the trajectory; determining the second process simplification variable according to the first process simplification variable and the elliptical fitting points.

[0084] The first process simplification variable can be a variable formed based on the trajectory starting point and the trajectory ending point, and capable of simplifying the elliptical arc coefficient formula. The second process simplification variable can be a variable formed based on the first process simplification variable and the elliptical fitting points, and capable of simplifying the elliptical arc coefficient formula.

[0085] In step 206, according to the elliptical arc construction equation, the elliptical arc coefficient formula, and the process simplification variable, determine the elliptical arc coefficient simplification formula.

[0086] The elliptical arc coefficient simplification formula can be an expression obtained by simplifying the elliptical arc coefficient formula based on the elliptical arc construction equation and the process simplification variable, and capable of reflecting the correlation relationship between the component coefficients in the elliptical arc construction equation.

[0087] According to the elliptical arc construction equation, the elliptical arc coefficient formula, and the process simplification variable, determine the elliptical arc coefficient simplification formula. The situations of determining the elliptical arc coefficient simplification formula include: according to the elliptical arc construction equation, the elliptical arc coefficient formula, and the first process simplification variable, determine the simplified elliptical arc construction equation; according to the simplified elliptical arc construction equation and the second process simplification variable, determine the elliptical arc coefficient simplification formula.

[0088] The simplified elliptical arc construction equation can be an equation obtained by simplifying the elliptical arc construction equation based on the elliptical arc coefficient formula and the first process simplification variable, and capable of being the construction equation required for elliptical arc fitting of the machining trajectory.

[0089] In step 208, according to the contour error constraint value, the elliptical arc coefficient simplification formula, and the interval of the point set to be fitted, determine the elliptical arc fitting information of multiple linear sub-machining trajectories.

[0090] The situations of determining the elliptical arc fitting information of multiple linear sub-machining trajectories according to the contour error constraint value, the elliptical arc coefficient simplification formula, and the interval of the point set to be fitted include: according to the elliptical arc coefficient simplification formula and the interval of the point set to be fitted, determine the initial elliptical arc fitting coefficient; according to the initial elliptical arc fitting coefficient, determine the elliptical arc fitting error value; according to the initial elliptical arc fitting coefficient, the elliptical arc fitting error value, and the contour error constraint value, determine the elliptical arc fitting information.

[0091] The initial elliptical arc fitting coefficient can be a coefficient formed based on the elliptical arc coefficient simplification formula and the interval of the point set to be fitted, and capable of initially fitting the machining fitting elliptical arc of the machining trajectory. The elliptical arc fitting error value can be a value formed based on the elliptical arc fitting coefficient, and capable of reflecting the error magnitude of the machining fitting elliptical arc of the initially fitted machining trajectory.

[0092] It should be noted that when the elliptical arc fitting error value of the machining fitting elliptical arc of the machining trajectory obtained based on the preliminary elliptical arc fitting coefficients is less than or equal to the contour error constraint value of the machining trajectory, it means that the error value of the machining fitting elliptical arc meets the machining accuracy requirements of the machining trajectory, and the machining trajectory can perform elliptical arc fitting according to the initial elliptical arc fitting coefficients; when the elliptical arc fitting error value of the machining fitting elliptical arc of the machining trajectory obtained based on the preliminary elliptical arc fitting coefficients is greater than the contour error constraint value of the machining trajectory, it means that the error value of the machining fitting elliptical arc is relatively large, and the elliptical arc fitting cannot be performed on the interval of the point set to be fitted of the machining trajectory.

[0093] During the fitting process of the machining trajectory of the component, according to the number of fitting points, the starting point of the trajectory, the ending point of the trajectory, and the elliptical arc construction equation, the elliptical arc coefficient formula is determined; according to the vertical axis coordinates of the starting point and the ending point of the trajectory, the first process simplification variable is determined; according to the first process simplification variable and the elliptical fitting points, the second process simplification variable is determined; according to the elliptical arc construction equation, the elliptical arc coefficient formula, and the first process simplification variable, the simplified elliptical arc construction equation is determined; according to the simplified elliptical arc construction equation and the second process simplification variable, the simplified elliptical arc coefficient formula is determined; according to the simplified elliptical arc coefficient formula and the interval of the point set to be fitted, the initial elliptical arc fitting coefficients are determined; according to the initial elliptical arc fitting coefficients, the elliptical arc fitting error value is determined; according to the initial elliptical arc fitting coefficients, the elliptical arc fitting error value, and the contour error constraint value, the elliptical arc fitting information is determined.

[0094] The trajectory fitting method provided in this embodiment realizes multiple simplification processes for each component coefficient in the elliptical arc construction equation through the number of fitting points, the starting point of the trajectory, the ending point of the trajectory, and the elliptical fitting points, until the simplified elliptical arc coefficient formula is obtained. Combining with the interval of the point set to be fitted, the initial elliptical arc fitting coefficients for the machining fitting elliptical arc that can initially fit the machining trajectory are determined. Then, the contour error constraint value is used to detect the error of the machining fitting elliptical arc of the machining trajectory obtained based on the preliminary elliptical arc fitting coefficients, and further the elliptical arc fitting information that meets the machining accuracy of the machining trajectory is obtained. While ensuring that the machining fitting elliptical arc of the machining trajectory meets the machining accuracy, the feasibility and implementability of the trajectory fitting method are effectively improved.

[0095] Figure 3 is a schematic flowchart of step 102 in an embodiment.

[0096] In this embodiment, as Figure 3 shown, this step 102 includes sub-steps 302 to 304.

[0097] Sub-step 302, obtain the contour error constraint value of the machining trajectory, the starting point of the trajectory, the ending point of the trajectory, and the angular deflection amount of adjacent linear sub-machining trajectories.

[0098] In step 304, according to the contour error constraint value, the trajectory starting point, the trajectory ending point, and the angle deflection amount, determine the interval of the point set to be fitted for multiple linear sub-processing trajectories.

[0099] The angle deflection amount can be the angle of relative deflection between the trajectory starting point and the trajectory ending point of adjacent linear sub-processing trajectories.

[0100] The situations of determining the elliptical arc fitting information of multiple linear sub-processing trajectories according to the contour error constraint value, the trajectory starting point, the trajectory ending point, and the interval of the point set to be fitted include: determining the initial elliptical arc fitting point set of multiple linear sub-processing trajectories according to the trajectory starting point, the trajectory ending point, and the angle deflection amount; determining the interval of the point set to be fitted according to the contour error constraint value and the initial elliptical arc fitting point set.

[0101] The initial elliptical arc fitting point set can be formed based on the trajectory starting point, the trajectory ending point, and the angle deflection amount of the processing trajectory, and is the range of the initial point set that can perform elliptical arc fitting on the processing trajectory.

[0102] The trajectory fitting method provided in this embodiment obtains the initial elliptical arc fitting point set of multiple linear sub-processing trajectories through the contour error constraint value, the trajectory starting point, the trajectory ending point, and the angle deflection amount of adjacent linear sub-processing trajectories, and combines the contour error constraint value to obtain the interval of the point set to be fitted that meets the processing accuracy of the processing trajectory, effectively improving the feasibility and implementability of the trajectory fitting method.

[0103] Figure 4 is a schematic diagram of the specific process of step 106 in an embodiment.

[0104] In this embodiment, as Figure 4 shown, this step 106 includes sub-steps 402 to sub-step 406.

[0105] In sub-step 402, according to the elliptical arc fitting information, determine the elliptical arc length value within a unit period.

[0106] In sub-step 404, according to the elliptical arc length value, determine the machining interpolation position of the processing trajectory.

[0107] In sub-step 406, according to the machining interpolation position, determine the machining fitting elliptical arc.

[0108] The elliptical arc length value can be formed based on the elliptical arc fitting information and can reflect the length of the elliptical arc to be machined within a unit period. The machining interpolation position can be the position for real-time interpolation of the machining fitting elliptical arc of the processing trajectory.

[0109] The trajectory fitting method provided in this embodiment obtains the length value of the elliptical arc to be processed within a unit period through the elliptical arc fitting information, and determines the machining interpolation position of the machining trajectory during the machining of the component according to the obtained elliptical arc length value, so as to realize the real-time interpolation of the machining fitting elliptical arc, ensure the real-time feedback of the machining process, and thus improve the trajectory fitting efficiency.

[0110] For example, as Figure 5 shown, the chord length corresponding to the circular arc P i-1 P i P i+1 is P i-1 P i and P i P i+1 , and R is the radius of the circular arc P i-1 P i P i+1 . According to the convex hull property of the machining fitting elliptical arc of the machining trajectory, by recording the angle deflection amount, the trajectory starting point and the trajectory ending point, the initial elliptical arc fitting point set of multiple linear sub-machining trajectories is determined. Specifically, the expression is as follows:

[0111]

[0112] That is, by judging the sign change of the angle deflection amount θ i of multiple linear sub-machining trajectories, the point set between two adjacent sign changes is used as the initial elliptical arc fitting point set.

[0113] In addition, to ensure the high-precision fitting effect of the elliptical arc, the bow height errors before and after the fitting point P i are also detected to see if they exceed the maximum profile error ε max . If it exceeds ε max , the point P i needs to be set as a non-fittable break point, otherwise the point P i is put into the fittable point set . The bilateral error criterion formula is as follows:

[0114] δ1 = R(1 - cosφ1)

[0115] δ2 = R(1 - cosφ2) = R(1 - cos(θi - φ1))

[0116] Among them, δ1 and δ2 are the bow height errors corresponding to the chord lengths P i-1 P i P i+1 and P i-1 P i and P i P i+1 respectively, and R is the circular arc Pi-1 P i P i+1 The radius of, φ1 and φ2 are respectively the chord lengths P i-1 P i and P i P i+1 and half of the corresponding central angles.

[0117] Next, it is necessary to judge the number n of fitting points in the interval of the point set to be fitted . If the number n of fitting points is less than 5, the elliptical arc fitting of the machining trajectory cannot be carried out; otherwise, the following method is used to fit the elliptical arc of the machining trajectory.

[0118] The general coefficient equation of the ellipse, that is, the elliptical arc construction equation is as follows:

[0119] x 2 +axy + by 2 +cx + dy + e = 0 (1)

[0120] In the formula, the ellipse has 5 unknown coefficients a, b, c, d, e. To ensure the continuity of the machined fitting elliptical arc, the machined fitting elliptical arc must pass through the trajectory starting point (x0, y0) and the trajectory ending point (x n , y n ):

[0121]

[0122] From (2) - (3), it can be obtained that:

[0123]

[0124] When (y0 - y n ) ≠ 0, the elliptical arc coefficient formula d can be known:

[0125]

[0126] Multiply (2) by y n -(3) by y0, and the elliptical arc coefficient formula e can be known:

[0127]

[0128] According to the vertical axis coordinates of the trajectory starting point and the trajectory ending point, determine the first process simplified variables, that is, let L = -y n y0, N = (x0 + x n ) Then F = NI, K = -LI.

[0129] The above two elliptical arc coefficient formulas can be simplified to:

[0130] d = aG + bH + cI + NI (5)

[0131] e = -aLI + bL + cM + J (6)

[0132] According to the elliptical arc construction equation, the elliptical arc coefficient formula, and the first - process simplified variables, determine the simplified elliptical arc construction equation, that is, substitute the above two formulas into (1) and simplify to get:

[0133] x 2 + a(xy + Gy - LI) + b(y 2 + Hy + L) + c(x + Iy + M) + NIy + J = 0 (7)

[0134] For equation (4), when (y0 - y n ) = 0, equation (4) simplifies to:

[0135]

[0136] When (x0 - x n ) = 0, the starting point and the ending point of the trajectory of the fitted elliptical arc are the same point, and the conditions for fitting the elliptical arc are insufficient, so the elliptical arc fitting is not performed.

[0137] When (x0 - x n ) ≠ 0, then the above formula can be simplified to:

[0138]

[0139] Multiply (2) by x n - (3) by x0 to get:

[0140]

[0141] According to the vertical - axis coordinates of both the starting point and the ending point of the trajectory, determine the first - process simplified variables, that is, let Then:

[0142] c = AA + aBB (8)

[0143] e = AA + bCC + dBB (9)

[0144] Substitute the above two formulas into equation (1) to get:

[0145] x 2 + a(xy + BBx) + b(y 2 + CC) + d(y + BB) + AA(x + 1) = 0 (10)

[0146] It can be seen from observing equations (7) and (10) that there are still three unknown coefficients in the general coefficient equation of the ellipse. (The three unknown coefficients in equation (7) are a, b, and c, and the three unknown coefficients in equation (10) are a, b, and d. Assume that the fitted ellipse must also pass through two other ellipse fitting points (x1, y1) and (x n-1 , y n-1 ).

[0147] Taking equation (7) as an example, similarly substitute the fixed points (x1, y1) and (x n-1 , y n-1 ) into equation (7) to get:

[0148]

[0149] According to the first process to simplify variables and ellipse fitting points, determine the second process to simplify variables, that is, let O1 = x1y1 + Gy1 - LI, Q1 = x1 + Iy1 + M, R1 = Ny1 + J, R n-1 = Ny n-1 + J,

[0150] O n-1 = x n-1 y n-1 + Gy n-1 - LI, Q n-1 = x n-1 + Iy n-1 + M, then the above formula can be simplified to:

[0151]

[0152] (11) - (12) gives:

[0153]

[0154] When Q1 - Q n-1 ≠ 0, according to the ellipse arc simplified construction equation and the second process to simplify variables, determine the ellipse arc coefficient simplified formula, then there is:

[0155]

[0156] Let Then the above formula can be further simplified to:

[0157] c = aS + bT + U (14)

[0158] (11) * Q n-1 - (12) * Q1 gives:

[0159]

[0160] When P n-1 Q1 - P1Q n-1 ≠ 0, according to the simplified construction equation of the elliptical arc and the simplified variables in the second process, the simplified formula of the elliptical arc coefficients is determined, and then there is:

[0161]

[0162] Let Then the simplified formula of the elliptical arc coefficients b and c can be further simplified as follows:

[0163] b = aV + W

[0164] c = aS + bT + U = a(S + VT) + WT + U

[0165] Let Z1 = W, Z2 = S + VT, Z3 = WT + U, then the above formula can be further simplified as follows:

[0166]

[0167] Substitute the above two formulas into formula (5) and formula (6) respectively, and after simplification, we get:

[0168] d = aG + (aV + Z1)H + (N + aZ2 + Z3)I = a(G + VH + Z2I) + Z1H + (N + Z3)I

[0169] e = (aV + Z1 - aI)L + (aZ2 + Z3)M + J = a(VL - IL + Z2M) + J + Z1L + Z3M

[0170] Let Z4 = G + XH + Z2I, Z5 = Z1H + (N + Z3)I, Z6 = XL - IL + Z2M, Z7 = J + Z1L + Z3M, then the above formula is further simplified as follows:

[0171]

[0172] The above formula is an expression only about the coefficient a. Therefore, we use the least - squares principle to find the partial derivative of the coefficient a

[0173]

[0174] By combining like terms, we get:

[0175]

[0176] When the fitted elliptical arc does not exist.

[0177] When from the above formula, we know that:

[0178]

[0179] After substituting the above equations into (16) and (17) respectively, the simplified equations of other elliptical arc coefficients b, c, d, and e for machining the fitted elliptical arc can be obtained.

[0180] For equation (15), similarly, when P n-1 Q1 - P1Q n-1 = 0, then there is:

[0181]

[0182] If O1Q n-1 - O n-1 Q1 = 0, then the fitted elliptical arc does not exist.

[0183] If O1Q n-1 - O n-1 Q1 ≠ 0, according to the simplified construction equation of the elliptical arc and the simplified variables in the second process, the simplified equation of the elliptical arc coefficients is determined, and the simplified equation of the elliptical arc coefficient a is:

[0184]

[0185] Substitute the simplified equation of the elliptical arc coefficient a into equations (5), (6), and (14) respectively, then the remaining unknown simplified equations of the elliptical arc coefficients c, d, and e are expressed in terms of the simplified equation of the elliptical arc coefficient b:

[0186] c = bT + U + aS

[0187] d = bH + cI + NI + aG = b(H + TI) + (U + aS)I + NI + aG e = bL + cM + J - aLI = b(L + TM) + (U + aS)M + J - aLI Let Z8 = U + aS, Z9 = Z8I + NI + aG, Z 10 = Z8M + J - aLI, Z 11 = H + TI, Z 12 = L + TM, then the above equations are further simplified to:

[0188]

[0189] Substitute the above equations into to get:

[0190]

[0191] The above equation is only about the simplified equation of the elliptical arc coefficient b. Take the partial derivative of the coefficient b according to the least squares principle That is:

[0192]

[0193] Further simplification gives:

[0194]

[0195] When the fitted elliptical arc does not exist.

[0196] When from the above equation, we know that:

[0197]

[0198] With the elliptical arc coefficient a known, substituting the above equation into (18) respectively, the simplified equations for the other coefficients c, d, and e of the fitted elliptical arc can be obtained.

[0199] For equation (13), similarly, when Q1 - Q n-1 = 0, after simplification, we have:

[0200]

[0201] When (P1 - P n-1 ) ≠ 0, according to the simplified construction equation of the elliptical arc and the simplified variables in the second process, the simplified equation of the elliptical arc coefficient is determined, and then we have:

[0202] Let then b = aZ 14 + Z 13 , substituting into equations (5) and (6), the simplified equation of the elliptical arc coefficient is:

[0203] d = a(G + Z 14 H) + cI + NI + Z 13 H

[0204] e = a(Z 14 L - LI) + cM + J + Z 13 L

[0205] Let Z 15 = G + Z 14 H, Z 16 = NI + Z 13 H, Z 17 = Z 14 L - LI, Z 18 = J + Z 13 L, the above equations are simplified to:

[0206]

[0207] The above formula is an expression only about the coefficients a and c of the elliptical arc. According to the principle of least squares, the partial derivatives of the coefficients a and c of the elliptical arc are obtained respectively. Then we have:

[0208]

[0209] Let

[0210] Then the above formula is simplified to:

[0211] Z 19 + aZ 21 + cZ 20 = 0 (21)

[0212] Z 22 + aZ 24 + cZ 23 = 0 (22)

[0213] (21) * Z 23 - (22) * Z 20 , the above formula is simplified to:

[0214] Z 19 Z 23 - Z 22 Z 20 + a(Z 21 Z 23 - Z 24 Z 20 ) = 0

[0215] When Z 21 Z 23 - Z 24 Z 20 = 0, the above formula has no solution and the fitted ellipse does not exist.

[0216] When Z 21 Z 23 - Z 24 Z 20 ≠ 0, the coefficients a and c of the fitted elliptical arc are:

[0217]

[0218] When Z 23 ≠ 0, (Or, Z 20 ≠ 0, ). When the coefficient b of the elliptical arc is known, substituting the coefficients a and c of the elliptical arc into formula (20) respectively, the other coefficients d and e of the fitted elliptical arc can be obtained.

[0219] For formula (19), similarly, when (P1 - P n-1) = 0, after simplification, we have:

[0220]

[0221] When O1 - O n-1 = 0, the above equation has no solution and the fitted elliptical arc does not exist.

[0222] When O1 - O n-1 ≠0, according to the simplified construction equation of the elliptical arc and the simplified variables in the second process, the simplified expression of the elliptical arc coefficients is determined, and then we have:

[0223] Let Substitute (4), (5) and a into it and simplify to get:

[0224]

[0225] The above formula is an expression only about the elliptical arc coefficients b and c. Use the least squares method to find the partial derivatives of the elliptical arc coefficients b and c respectively

[0226]

[0227] Let

[0228] Then the above formula is simplified to:

[0229] Z 25 + cZ 26 + bZ 27 = 0 (24)

[0230] Z 28 + cZ 29 + bZ 30 = 0 (25)

[0231] (24) * Z 30 - (25) * Z 27 , the above formula is simplified to:

[0232] Z 25 Z 30 - Z 28 Z 27 + c(Z 26 Z 30 - Z 29 Z 27 ) = 0

[0233] When Z 26 Z 30 - Z 29 Z 27 = 0, the above formula has no solution and the ellipse does not exist.

[0234] When Z 26 Z 30 -Z 29 Z 27 ≠ 0, at this time, the elliptical arc coefficients c and b are:

[0235]

[0236] When Z 27 ≠ 0, (Or, Z 30 ≠ 0, ). Substitute the elliptical arc coefficients a, b, and c into equations (5) and (6) respectively, and the elliptical arc coefficients d and e can be obtained.

[0237] Continuing with equation (10) as an example, similarly substitute the two elliptical fitting points (x1, y1) and (x n-1 , y n-1 ) into equation (10) to get:

[0238]

[0239] According to the first process of simplifying variables and elliptical fitting points, determine the second process of simplifying variables, that is, let D1 = x1y1 + BBx1, F1 = y1 + BB, D n-1 = x n-1 y n-1 + BBx n-1 ,

[0240] F n-1 = y n-1 + BB, Then, according to the elliptical arc simplified construction equation and the second process of simplifying variables, determine the simplified formula of the elliptical arc coefficients, that is, the above formula is simplified to:

[0241] aD1 + bE1 + dF1 + G1 = 0 (26)

[0242] aD n-1 + bE n-1 + dF n-1 + G n-1 = 0 (27)

[0243] (26)*F n-1 -(27)*F1, after further simplification, we get:

[0244] a(D1F n-1 - D n-1 F1) + b(E1F n-1 - E n-1F1)+G1F n-1 -G n-1 F1 = 0 (28)

[0245] When (E1F n-1 -E n-1 When (F1) ≠ 0, according to the elliptical arc simplification construction equation and the second - process simplified variables, determine the elliptical arc coefficient simplified formula b:

[0246]

[0247] Let Then the above formula can be simplified to b = Z 31 +aZ 32 .

[0248] Substitute it into Equation (9), after simplification, we get e = aZ 32 CC + dBB + AA + Z 31 CC. Substitute the elliptical arc coefficient simplified formulas b and e into

[0249]

[0250] It can be seen that the above - mentioned expression is only related to the elliptical arc coefficients a and d. According to the least - squares method principle, take the partial derivatives of the coefficients a and d respectively

[0251]

[0252] Let

[0253]

[0254] Then the above formula is simplified to:

[0255] Z 32 +aZ 33 +dZ 34 = 0 (30)

[0256] Z 35 +aZ 36 +dZ 37 = 0 (31)

[0257] Z 37 *(31)-Z 34 *(30), after simplification, we get:

[0258] (Z 32 -Z 35 )+a(Z 33 -Z 36 ) = 0

[0259] If (Z33 -Z 36 ) = 0, the fitted elliptical arc does not exist.

[0260] If (Z 33 -Z 36 ) ≠ 0, then the elliptical coefficients If Z 34 ≠ 0, substitute it into Equation (29), then the elliptical coefficients Otherwise, judge whether Z 37 is 0. If Z 37 = 0, then the ellipse has no solution. Otherwise, the elliptical coefficients

[0261] Finally, substitute the elliptical arc coefficients a and d into Equation (29), Equation (8) and Equation (9) respectively to solve the corresponding elliptical arc coefficients b, c, and e.

[0262] For Equation (28), similarly, if (E1F n-1 -E n-1 F1) = 0, then Equation (28) simplifies to:

[0263] a(D1F n-1 -D n-1 F1)+G1F n-1 -G n-1 F1 = 0

[0264] If D1F n-1 -D n-1 F1 = 0, then the ellipse is fitted. Otherwise, the elliptical arc coefficients At this time, for Equation (10)

[0265]

[0266] It can be seen that the above expression is only related to the elliptical arc coefficients b and d. According to the least squares principle, take the partial derivatives of the elliptical arc coefficients b and d respectively

[0267]

[0268] Let

[0269] Then the above equation can be simplified to:

[0270] Z 38 +bZ 39 +dZ 40 = 0 (30)

[0271] Z 41 +bZ 42 +dZ 43 = 0 (31)

[0272] Z 43 *(30)-Z 40 *(31), simplified to:

[0273] Z 38 Z 43 -Z 41 Z 40 +b(Z 39 Z 43 -Z 42 Z 40 ) = 0

[0274] If (Z 39 Z 43 -Z 42 Z 40 ) = 0, the fitted ellipse does not exist; otherwise, the ellipse arc coefficient If Z 40 ≠0, substitute it into equation (30), then the ellipse arc coefficient Otherwise, determine whether Z 43 is 0. If Z 43 = 0, the ellipse has no solution; otherwise, the ellipse arc coefficient

[0275] After the above fitting, the coefficients a, b, c, d, and e of the general equation of the ellipse arc fitting can be obtained. To ensure that the fitted conic curve is an ellipse arc, it is necessary to detect Δ = a 2 -4b < 0. If Δ = a 2 -4b ≥ 0, it means that the fitted conic curve is not an ellipse arc, and no further operation is performed.

[0276] Then, according to the ellipse arc coefficient simplification formula and the interval of the point set to be fitted, the initial ellipse arc fitting coefficients are determined, that is, calculate the ellipse center coordinates P0(x c , y c ), the ellipse rotation angle θ (the angle between the major axis and the positive x-axis), the major semi-axis and the minor semi-axis are R l and R s , the starting point and the ending point of the ellipse arc are P s and P e , the ellipse foci F1 and F2, the starting angle and the ending angle of the ellipse are θ s and θ e and the ellipse arc direction turn, as follows:

[0277]

[0278] In the above formula, the direction turn of the ellipse arc can be determined by the convexity t of the fitting interval i .

[0279] To ensure the machining accuracy of the fitted elliptical arc, we still need to perform accuracy detection on it. Assume Q i is a fitting point on the fitted elliptical arc except for the starting and ending points. According to the properties of the ellipse, the sum of the distances from any point on the ellipse to the two foci F1 and F2 is 2R l . Determine the fitting error value of the elliptical arc based on the initial elliptical arc fitting coefficients, and determine the elliptical arc fitting information based on the initial elliptical arc fitting coefficients, the elliptical arc fitting error value, and the contour error constraint value:

[0280] abs(||Q i F1|| + ||Q i F2|| - 2R l ) ≤ ε max

[0281] If the above conditions are met, it means that the error of the elliptical arc fitted by the point set is within the maximum contour error ε max . Otherwise, it means that the point set cannot be fitted into an elliptical arc, and no further operations are required.

[0282] Then, based on the elliptical arc fitting information, determine the length value of the elliptical arc within a unit period. Assume the elliptical equation is as Figure 6 shown. Divide the ellipse into four regions, and each region corresponds to different parameters as independent variables.

[0283] Taking y as the variable in the first quadrant as an example, then the arc length of the elliptical arc between any two points in this region is:

[0284]

[0285] In the above formula, is the expression of the elliptical equation with y as the independent variable and x as the dependent variable. According to the Gauss-Legendre quadrature formula, the above formula can be transformed into:

[0286]

[0287] In the above formula, For the cases where y or x is the variable in other quadrants, the derivation method of the elliptical arc length is the same as the above.

[0288] Next, based on the elliptical arc length value, determine the machining interpolation position of the machining trajectory, and based on the machining interpolation position, determine the machined fitted elliptical arc; first, determine the relationship between the elliptical arc length and the independent variable. Taking y as the independent variable in the first quadrant, taking the elliptical arc from point P0(R l , 0) to point as an example, the steps to solve the relationship between its arc length and the independent variable are as follows:

[0289] (1) In the interval of the independent variable y , respectively take the points and

[0290] (2) According to Equation (32), calculate the arc lengths s0, s1, s2, and s3 from y1, y2, and y3 to the starting point y0 of the elliptical arc respectively.

[0291] (3) Substitute the obtained elliptical arc lengths (s0, y0), (s1, y1), (s2, y2), (s3, y3) into the following cubic polynomial for interpolation, obtain the coefficients of the polynomial, and then the relationship between the elliptical arc length value and the variable can be obtained:

[0292] y = a0 + a1s + a2s 2 + a3s 3 , s ∈ [s0, s3]

[0293] For the cases where y or x is the variable in other quadrants, the derivation method is the same as above.

[0294] To ensure the real-time interpolation of any elliptical arc, the above process needs to be preprocessed in look-ahead. After the preprocessing is completed, the kernel system of laser cutting will obtain the elliptical arc segment to be processed, and calculate the interpolation point coordinates (x t , y t ) of the laser cutting according to the relationship between the elliptical arc length to be processed per unit cycle and the independent variable, that is, the real-time interpolation of the elliptical arc is completed.

[0295] The above trajectory fitting method mainly includes three steps: The first step is to use the rough division method of convex hull detection and bilateral chord height error method to divide the continuous small line segments into several intervals to be fitted, improving the processing efficiency of a large amount of data; The second step is to add endpoint constraints on the basis of fitting the ellipse by the least squares method, which not only realizes that the fitted elliptical arc passes through the starting and ending points of the fitting point set, ensuring the continuous processing of elliptical arc segments in different components in a large format, but also restricts the accuracy of the fitted elliptical arc under the maximum contour error according to the ellipse properties, improving the processing efficiency of the laser cutting machine tool; The third step is to calculate the arc length of any elliptical arc according to the Gauss-Legendre quadrature formula and establish the relationship between the elliptical arc length and the independent variable, realizing the real-time interpolation of the elliptical arc, thereby realizing the real-time interpolation of the processed fitted elliptical arc, ensuring the real-time feedback of the processing process, and thus improving the trajectory fitting efficiency.

[0296] It should be understood that although the steps in the above flowcharts are shown sequentially according to the prompts of the arrows, these steps are not necessarily executed in the order prompted by the arrows. Unless there is a clear indication in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, at least one of the sub-steps in the above can include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same moment, but can be executed at different moments. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed alternately or in turn with at least a part of other steps or sub-steps or stages of other steps. It should be noted that the above different embodiments can be combined with each other.

[0297] Figure 7 , is a schematic block diagram of the structure of a trajectory fitting device in an embodiment.

[0298] In this embodiment, as Figure 7 shown, the trajectory fitting device is applied to a machining trajectory including a plurality of linear sub-machining trajectories. The trajectory fitting device includes an acquisition module 20, a fitting information determination module 40, and a machining module 60.

[0299] The acquisition module 20 is configured to acquire the contour error constraint value, the trajectory start point, the trajectory end point, and the set interval of points to be fitted of the machining trajectory.

[0300] The fitting information determination module 40 is connected to the acquisition module 20 and is configured to determine the elliptical arc fitting information of the plurality of linear sub-machining trajectories according to the contour error constraint value, the trajectory start point, the trajectory end point, and the set interval of points to be fitted.

[0301] The machining module 60 is connected to the fitting information determination module 40 and is configured to determine the machining fitting elliptical arc of the machining trajectory according to the elliptical arc fitting information.

[0302] In this embodiment, each module is used to execute Figure 1 the corresponding steps in the corresponding embodiment in Figure 1 and Figure 1 the relevant descriptions in the corresponding embodiment, which will not be elaborated here.

[0303] The trajectory fitting device provided in this embodiment determines the ellipse arc fitting information of multiple linear sub-processing trajectories according to the contour error constraint value of the processing trajectory, the starting point of the trajectory, the ending point of the trajectory, and the interval of the point set to be fitted, and fits a processing fitting ellipse arc that satisfies the contour error constraint value of the processing trajectory, passes through the starting point and the ending point of the trajectory, and is applicable to the processing trajectory with multiple linear sub-processing trajectories according to the obtained ellipse arc fitting information. Compared with the initial processing trajectory, it can effectively improve the smoothness of the trajectory at the connection of adjacent linear sub-processing trajectories while satisfying the processing accuracy constraint of the processing trajectory, thereby maintaining a large feed speed at the connection of adjacent linear sub-processing trajectories, ensuring the continuity of the speed and acceleration at each part of the processing trajectory, improving the problem of abnormal vibration of the machine tool caused by uneven change of the trajectory curvature at each part of the processing trajectory, and also realizing the continuous and uninterrupted processing of multiple processing fitting ellipse arcs in the processing trajectory of large-scale components, which can improve the laser processing efficiency.

[0304] Figure 8 is a schematic structural block diagram of the fitting information determination module 40 in an embodiment.

[0305] In this embodiment, as Figure 8 shown, the fitting information determination module 40 includes a coefficient formula determination unit 410, a simplified variable determination unit 420, a coefficient simplification unit 430, and a fitting information determination unit 440.

[0306] The coefficient formula determination unit 410 is configured to determine the ellipse arc coefficient formula according to the number of fitting points, the starting point of the trajectory, the ending point of the trajectory, and the ellipse arc construction equation.

[0307] The simplified variable determination unit 420 is connected to the coefficient formula determination unit 410 and is configured to determine the process simplified variable according to the starting point of the trajectory, the ending point of the trajectory, and the ellipse fitting points.

[0308] The coefficient simplification unit 430 is connected to the coefficient formula determination unit 410 and the simplified variable determination unit 420, and is configured to determine the ellipse arc coefficient simplified formula according to the ellipse arc construction equation, the ellipse arc coefficient formula, and the process simplified variable.

[0309] The fitting information determination unit 440 is connected to the coefficient simplification unit 430 and is configured to determine the ellipse arc fitting information of multiple linear sub-processing trajectories according to the contour error constraint value, the ellipse arc coefficient simplified formula, and the interval of the point set to be fitted.

[0310] In this embodiment, each unit is used to execute Figure 2 the corresponding steps in the corresponding embodiment, specifically refer to Figure 2 and Figure 2 the relevant descriptions in the corresponding embodiment, which will not be elaborated here.

[0311] Figure 9 , which is a schematic block diagram of the specific structure of the acquisition module 20 in an embodiment.

[0312] In this embodiment, as Figure 9 shown, the acquisition module 20 includes a parameter acquisition unit 210 and a fitting point set determination unit 220.

[0313] The parameter acquisition unit 210 is configured to acquire the contour error constraint value of the machining trajectory, the starting point of the trajectory, the ending point of the trajectory, and the angular deflection amount between adjacent linear sub-machining trajectories.

[0314] The fitting point set determination unit 220 is connected to the parameter acquisition unit 210, and is configured to determine the interval of the fitting point set of multiple linear sub-machining trajectories according to the contour error constraint value, the starting point of the trajectory, the ending point of the trajectory, and the angular deflection amount.

[0315] In this embodiment, each unit is used to execute Figure 3 the corresponding steps in the corresponding embodiment in Figure 3 and Figure 3 the relevant descriptions in the corresponding embodiment, which will not be elaborated here.

[0316] Figure 10 , which is a schematic block diagram of the specific structure of the machining module 60 in an embodiment.

[0317] In this embodiment, as Figure 10 shown, the machining module 60 includes an arc length determination unit 610, an interpolation position determination unit 620, and a machining unit 630.

[0318] The arc length determination unit 610 is configured to determine the ellipse arc length value within a unit period according to the ellipse arc fitting information.

[0319] The interpolation position determination unit 620 is connected to the arc length determination unit 610, and is configured to determine the machining interpolation position of the machining trajectory according to the ellipse arc length value.

[0320] The machining unit 630 is connected to the interpolation position determination unit 620, and is configured to determine the machining fitting ellipse arc according to the machining interpolation position.

[0321] In this embodiment, each unit is used to execute Figure 4 the corresponding steps in the corresponding embodiment in Figure 4 and Figure 4 the relevant descriptions in the corresponding embodiment, which will not be elaborated here.

[0322] In the above embodiments, each unit is used to execute the corresponding steps in the foregoing embodiments. For specific reference, please refer to the relevant descriptions in the foregoing corresponding embodiments, which will not be elaborated herein.

[0323] The division of each module in the above trajectory fitting device is only for illustrative purposes. In other embodiments, the trajectory fitting device can be divided into different modules as needed to complete all or part of the functions of the above trajectory fitting device.

[0324] For the specific limitations of the trajectory fitting device, reference can be made to the limitations on the trajectory fitting method in the foregoing text, which will not be elaborated herein. Each module in the above trajectory fitting device can be implemented in whole or in part by software, hardware, and their combinations. The above modules can be embedded in the processor of the processing device in hardware form or independent of it, or stored in the memory of the processing device in software form, so that the processor can call and execute the operations corresponding to the above modules.

[0325] Figure 11 , which is a schematic structural diagram of a processing device in an embodiment.

[0326] In this embodiment, as Figure 11 shown, the processing device includes a memory A1 (memory) and a processor A2 (processor); it may also include a display screen A3, a communication interface (Communications Interface), and a bus. Optionally, the processing device may be a laser processing device.

[0327] Among them, the memory A1, the processor A2, the display screen A3, and the communication interface can communicate with each other through the bus; the display screen A3 is set to display the preset user operation interface in the initial setting mode, and at the same time, the display screen A3 can also display the process control window; the communication interface can transmit information; the memory A1 stores a computer program, and the processor A2 can call the logical instructions in the memory A1 to execute the method in the above embodiments.

[0328] In addition, the logical instructions in the above memory A1 can be implemented in the form of software function units and, when sold or used independently as a workpiece, can be stored in a computer-readable storage medium.

[0329] The memory A1, as a computer-readable storage medium, can be set to store software programs and computer-executable programs, such as the program instructions or modules corresponding to the method in the embodiments of the present application. The processor A2 executes functional applications and data processing by running the software programs, instructions, or modules stored in the memory A1, that is, implements the method in the above embodiments.

[0330] The memory A1 includes a program storage area and a data storage area. Among them, the program storage area can store an operating system and application programs required for at least one function; the data storage area can store data created according to the use of the terminal device, etc. In addition, the memory A1 may include a high-speed random access memory and may also include a non-volatile memory.

[0331] The processor A2 can be a central processing unit (CPU), or can also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.

[0332] The embodiments of the present application also provide a computer-readable storage medium. One or more non-volatile computer-readable storage media containing computer-executable instructions, when the computer-executable instructions are executed by one or more processors, cause the processors to execute the methods in the above embodiments.

[0333] The embodiments of the present application also provide a computer program product. When the computer program product runs on a terminal device, the terminal device is caused to execute the methods in the above embodiments.

[0334] The trajectory fitting method, device, processing equipment, and readable storage medium provided in the above embodiments determine the elliptical arc fitting information of multiple linear sub-processing trajectories according to the contour error constraint value of the processing trajectory, the trajectory start point, the trajectory end point, and the set interval of points to be fitted, and according to the obtained elliptical arc fitting information, thus fitting a processing fitting elliptical arc that satisfies the contour error constraint value of the processing trajectory, passes through the trajectory start point and the trajectory end point, and is applicable to a processing trajectory with multiple linear sub-processing trajectories. Compared with the initial processing trajectory, it can effectively improve the smoothness of the trajectory at the connection of adjacent linear sub-processing trajectories while meeting the processing accuracy constraint of the processing trajectory, so as to maintain a large feed speed at the connection of adjacent linear sub-processing trajectories, ensure the continuity of the speed and acceleration at each part of the processing trajectory, improve the problem of abnormal vibration of the machine tool caused by uneven change of the trajectory curvature at each part of the processing trajectory, and also realize the continuous and uninterrupted processing of multiple processing fitting elliptical arcs in the processing trajectory of large-format parts, which can improve the laser processing efficiency and has important economic value and practical value for popularization.

[0335] Any reference to memory, storage, database, or other media used in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM), which acts as an 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), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM).

[0336] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0337] The above-described embodiments merely represent several implementation manners of this application. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of this application, several modifications and improvements can still be made, and these all belong to the protection scope of this application. Therefore, the protection scope of the patent of this application shall be subject to the appended claims.

Claims

1. A trajectory fitting method, applied to a machining trajectory including a plurality of linear sub-machining trajectories, characterized in that: include: Obtaining a contour error constraint value, a trajectory starting point, a trajectory ending point, and an interval of a point set to be fitted of the machining trajectory; Determining elliptical arc fitting information of the plurality of linear sub-machining trajectories according to the contour error constraint value, the trajectory starting point, the trajectory ending point and the interval of the set of points to be fitted; According to the elliptical arc fitting information, a machining fitting elliptical arc of the machining trajectory is determined.

2. The trajectory fitting method according to claim 1, characterized in that: The step of determining the elliptical arc fitting information of the plurality of linear sub-machining trajectories according to the contour error constraint value, the trajectory starting point, the trajectory ending point and the interval of the point set to be fitted comprises: Obtaining the number of fitting points in the interval of the point set to be fitted; Determine, according to the trajectory starting point and the trajectory ending point, a plurality of ellipse fitting points of the linear sub-processing trajectory, wherein the ellipse fitting points are fitting points that pass through the processing fitting ellipse arc and do not coincide with the trajectory starting point and the trajectory ending point; The elliptical arc fitting information of the plurality of linear sub-machining trajectories is determined according to the contour error constraint value, the number of fitting points, the trajectory starting point, the trajectory ending point, the ellipse fitting point and the interval of the point set to be fitted.

3. The trajectory fitting method according to claim 2, characterized in that: Determining the elliptical arc fitting information of the plurality of linear sub-machining trajectories according to the contour error constraint value, the number of fitting points, the trajectory starting point, the trajectory ending point, the ellipse fitting point and the interval of the set of points to be fitted includes: Determine an elliptical arc coefficient formula according to the number of fitting points, the trajectory starting point, the trajectory ending point and the elliptical arc construction equation; Determine a process simplification variable according to the trajectory starting point, the trajectory ending point and the ellipse fitting point; Determine a simplified formula for elliptical arc coefficients according to the elliptical arc construction equation, the elliptical arc coefficient formula and the process simplified variables; The elliptical arc fitting information of the plurality of linear sub-machining trajectories is determined according to the contour error constraint value, the simplified formula of the elliptical arc coefficient and the interval of the point set to be fitted.

4. The trajectory fitting method according to claim 3, characterized in that: The step of determining a process simplification variable according to the trajectory starting point, the trajectory ending point and the ellipse fitting point comprises: Determine a first process simplified variable according to the longitudinal coordinates of the starting point of the trajectory and the ending point of the trajectory; Determining a second process simplified variable according to the first process simplified variable and the ellipse fitting point; The step of determining the simplified formula of the elliptical arc coefficient according to the elliptical arc construction equation, the elliptical arc coefficient formula and the process simplified variables comprises: Determine a simplified elliptical arc construction equation according to the elliptical arc construction equation, the elliptical arc coefficient formula and the first process simplified variable; Determining the simplified formula of the elliptical arc coefficient according to the simplified construction equation of the elliptical arc and the simplified variables of the second process; The step of determining the elliptical arc fitting information of the plurality of linear sub-machining trajectories according to the contour error constraint value, the simplified formula of the elliptical arc coefficient and the interval of the point set to be fitted comprises: Determining initial elliptical arc fitting coefficients according to the simplified elliptical arc coefficient formula and the interval of the point set to be fitted; Determining an elliptical arc fitting error value according to the initial elliptical arc fitting coefficient; The elliptical arc fitting information is determined according to the initial elliptical arc fitting coefficient, the elliptical arc fitting error value and the contour error constraint value.

5. The trajectory fitting method according to claim 1, characterized in that: The step of obtaining the contour error constraint value, the trajectory starting point, the trajectory ending point and the interval of the point set to be fitted of the machining trajectory includes: Obtaining a contour error constraint value of the processing trajectory, a trajectory starting point, a trajectory ending point, and an angular deflection amount of an adjacent linear sub-processing trajectory; According to the contour error constraint value, the trajectory starting point, the trajectory ending point and the angular deflection amount, a plurality of intervals of point sets to be fitted of the linear sub-machining trajectories are determined.

6. The trajectory fitting method according to claim 5, characterized in that: The step of determining the elliptical arc fitting information of the plurality of linear sub-machining trajectories according to the contour error constraint value, the trajectory starting point, the trajectory ending point and the interval of the point set to be fitted comprises: Determining a set of initial elliptical arc fitting points of a plurality of the linear sub-machining trajectories according to the trajectory starting point, the trajectory ending point and the angular deflection amount; The interval of the point set to be fitted is determined according to the contour error constraint value and the initial elliptical arc fitting point set.

7. The trajectory fitting method according to claim 1, characterized in that: The step of determining the machining fitting elliptical arc of the machining trajectory according to the elliptical arc fitting information includes: Determine the length value of the elliptical arc within a unit period according to the elliptical arc fitting information; Determining a machining interpolation position of the machining trajectory according to the elliptical arc length value; The machining fitting elliptical arc is determined according to the machining interpolation position.

8. A trajectory fitting device, applied to a processing trajectory including a plurality of linear sub-processing trajectories, characterized in that: include: An acquisition module, used to acquire the contour error constraint value, the trajectory starting point, the trajectory ending point and the interval of the point set to be fitted of the processing trajectory; A fitting information determination module, connected to the acquisition module, for determining elliptical arc fitting information of a plurality of the linear sub-machining trajectories according to the contour error constraint value, the trajectory starting point, the trajectory ending point and the interval of the point set to be fitted; The processing module is connected to the fitting information determination module and is used to determine the processing fitting elliptical arc of the processing trajectory according to the elliptical arc fitting information.

9. A processing equipment, characterized in that: The method comprises a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the method according to 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 a processor, the method according to any one of claims 1 to 7 is implemented.

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