阅读说明：本技术 一种应用于五轴数控机床的拐角过渡方法 (Corner transition method applied to five-axis numerical control machine tool ) 是由 不公告发明人 于 2021-07-30 设计创作，主要内容包括：本发明提供了一种应用于五轴数控机的拐角过渡方法及装置,属于数控机床技术领域,包括步骤：获取平动轴的过渡路径,过渡路径用于平滑连接第一直线加工段和第二直线加工段；获取第一线性关系和第二线性关系；第一线性关系是在第一直线加工段上,旋转轴的角度变化量与平动轴的行程长度的线性关系；第二线性关系是在第二直线加工段上,旋转轴的角度变化量与平动轴的行程长度的线性关系；根据第一线性关系和第二线性关系,确定过渡路径上对应的旋转轴的角度。本申请提供的方法,保证了五轴数控机床的平动轴和旋转轴的加工轨迹具有相当程度的加工精度、几何连续性、运动平顺性,解决了五轴数控机床的拐角过渡的问题。(The invention provides a corner transition method and a corner transition device applied to a five-axis numerical control machine, belonging to the technical field of numerical control machines and comprising the following steps: acquiring a transition path of the translational axis, wherein the transition path is used for smoothly connecting the first linear machining section and the second linear machining section; acquiring a first linear relation and a second linear relation; the first linear relation is the linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the first linear processing section; the second linear relation is the linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the second linear machining section; and determining the angle of the corresponding rotating shaft on the transition path according to the first linear relation and the second linear relation. The method provided by the application ensures that the machining tracks of the translational shaft and the rotating shaft of the five-axis numerical control machine tool have considerable machining precision, geometric continuity and movement smoothness, and solves the problem of corner transition of the five-axis numerical control machine tool.)

1. A corner transition method applied to a five-axis numerical control machine is characterized by comprising the following steps:

acquiring a transition path of a translational axis, wherein the transition path is used for smoothly connecting a first linear machining section and a second linear machining section;

acquiring a first linear relation and a second linear relation; the first linear relation is a linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the first linear machining section; the second linear relation is a linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the second linear machining section;

and determining the angle of the corresponding rotating shaft on the transition path according to the first linear relation and the second linear relation.

2. The corner transition method of claim 1, wherein determining the angle of the corresponding rotational axis on the transition path from the first linear relationship and the second linear relationship comprises:

determining the angle of a corresponding rotating shaft on an interval path from the transition starting point to the transition middle point according to the first linear relation;

and determining the angle of the corresponding rotating shaft on the interval path from the transition midpoint to the transition end point according to the second linear relation.

3. The corner transition method of claim 1, wherein the determining the angle of the corresponding rotational axis on the transition path from the first linear relationship and the second linear relationship comprises:

on the transition path, the angle variation of the rotating shaft and the displacement of the translational shaft in the direction of the first linear machining section have the first linear relation, the angle variation of the rotating shaft and the displacement of the translational shaft in the direction of the second linear machining section have the second linear relation, and the angle of the rotating shaft is determined according to the angle variation.

4. The corner transition method of claim 1, wherein the analytic expression of the transition path is represented as a NURBS form, the analytic expression including shape parameters for adjusting the shape of the transition path.

5. The corner transition method of claim 4, wherein the determining a transition path for a translational axis comprises:

acquiring a first contour error, wherein the first contour error is the shortest distance from the intersection point of the first linear machining section and the second linear machining section to the transition path;

determining a first value of a maximum transition distance according to the first contour error and the shape parameter;

and determining the transition path according to the first value and the analytic expression.

6. The corner transition method of claim 5, wherein the determining a transition path for a translational axis further comprises:

acquiring a second contour error;

determining a second value of the maximum transition distance according to the second contour error;

taking out the minimum value from the first value, the second value and half of the length of the linear machining section as the final maximum transition distance; the linear processing section comprises at least one of the first linear processing section and the second linear processing section.

And determining the transition path according to the final maximum transition distance.

7. The corner transition method of claim 6, wherein the second profile error is a difference in an angle of a corresponding rotational axis at an intersection of the first linear machining section and the second linear machining section and an angle at a midpoint of a transition path corresponding to the second profile error.

8. The corner transition method of claim 4, further comprising:

determining the maximum curvature of the transition path according to the shape parameter;

calculating a maximum velocity through the transition path based on the maximum curvature.

9. The utility model provides a be applied to turning transition device of five digit control machines which characterized in that includes:

the device comprises a first acquisition unit, a second acquisition unit and a third acquisition unit, wherein the first acquisition unit is used for acquiring a transition path of a translational shaft, and the transition path is used for smoothly connecting a first linear machining section and a second linear machining section;

a second acquisition unit configured to acquire the first linear relationship and the second linear relationship; the first linear relation is a linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the first linear machining section; the second linear relation is a linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the second linear machining section;

and the determining unit is used for determining the angle of the corresponding rotating shaft on the transition path according to the first linear relation and the second linear relation.

10. A computer program product, characterized in that the computer program product comprises a non-transitory computer readable storage medium storing a computer program, the program instructions being operable to perform the method of any of claims 1-8.

11. A computer-readable storage medium, characterized in that the computer storage medium stores program instructions that, when executed by a processor, cause the processor to perform the method of any of claims 1-8.

Technical Field

The invention belongs to the technical field of numerical control machining, and particularly relates to a corner transition method applied to a five-axis numerical control machine tool.

Background

The corner transition is mainly realized by inserting a transition curve at the joint of adjacent micro straight line sections, so that the smoothness of a numerical control machining track is realized, the speed of a moving part of a numerical control machine tool passing through the corner is improved, and the machining efficiency and the machining quality are improved. In the early years, the research related to corner transition is involved in a plurality of documents, but the attention points of the documents are mainly geometric analysis and three-axis application situations, and the research on the corner transition of a five-axis numerical control machine tool is less.

Disclosure of Invention

The invention aims to provide a corner transition method applied to a five-axis numerical control machine tool, and aims to solve the technical problem of how to realize corner transition in the five-axis numerical control machine tool.

In order to achieve the above object, in a first aspect, the present invention provides a corner transition method applied to a five-axis numerical control machine tool, including the steps of:

acquiring a transition path of a translational axis, wherein the transition path is used for smoothly connecting a first linear machining section and a second linear machining section;

acquiring a first linear relation and a second linear relation; the first linear relation is a linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the first linear machining section; the second linear relation is a linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the second linear machining section;

and determining the angle of the corresponding rotating shaft on the transition path according to the first linear relation and the second linear relation.

In one possible implementation, determining the angle of the corresponding rotation axis on the transition path according to the first linear relationship and the second linear relationship includes:

determining the angle of a corresponding rotating shaft on an interval path from the transition starting point to the transition middle point according to the first linear relation;

and determining the angle of the corresponding rotating shaft on the interval path from the transition midpoint to the transition end point according to the second linear relation.

In one possible implementation, the determining, according to the first linear relationship and the second linear relationship, an angle of a corresponding rotation axis on the transition path includes:

on the transition path, the angle variation of the rotating shaft and the displacement of the translational shaft in the direction of the first linear machining section have the first linear relation, the angle variation of the rotating shaft and the displacement of the translational shaft in the direction of the second linear machining section have the second linear relation, and the angle of the rotating shaft is determined according to the angle variation.

In one possible implementation, the analytic expression of the transition path is represented in NURBS form, and the analytic expression includes a shape parameter for adjusting the shape of the transition path.

In one possible implementation, the determining the transition path of the translational axis includes:

acquiring a first contour error, wherein the first contour error is the shortest distance from the intersection point of the first linear machining section and the second linear machining section to the transition path;

determining a first value of a maximum transition distance according to the first contour error and the shape parameter;

and determining the transition path according to the first value and the analytic expression.

In one possible implementation, the determining the transition path of the translational axis further includes:

acquiring a second contour error;

determining a second value of the maximum transition distance according to the second contour error;

taking out the minimum value from the first value, the second value and half of the length of the linear machining section as the final maximum transition distance; the linear processing section comprises at least one of the first linear processing section and the second linear processing section.

And determining the transition path according to the final maximum transition distance.

In one possible implementation, the second profile error is a difference between an angle of the rotating shaft corresponding to an intersection of the first linear machining section and the second linear machining section and an angle at a midpoint of the transition path corresponding to the second profile error.

In one possible implementation, the corner transition method further includes:

determining the maximum curvature of the transition path according to the shape parameter;

calculating a maximum velocity through the transition path based on the maximum curvature.

In a second aspect, the present application provides a corner transition device applied to a five-axis numerical control machine, including:

the device comprises a first acquisition unit, a second acquisition unit and a third acquisition unit, wherein the first acquisition unit is used for acquiring a transition path of a translational shaft, and the transition path is used for smoothly connecting a first linear machining section and a second linear machining section;

a second acquisition unit that acquires the first linear relationship and the second linear relationship; the first linear relation is a linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the first linear machining section; the second linear relation is a linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the second linear machining section;

and the determining unit is used for determining the angle of the corresponding rotating shaft on the transition path according to the first linear relation and the second linear relation.

In a third aspect, an embodiment of the present invention provides a computer-readable storage medium, where the computer-readable storage medium stores a computer program for electronic data exchange; the aforementioned computer program causes a computer to perform some or all of the steps as described in the first or second aspect of the embodiments of the present invention.

In a fourth aspect, embodiments of the present invention provide a computer program product, wherein the computer program product comprises a non-transitory computer readable storage medium storing a computer program, the computer program being operable to cause a computer to perform some or all of the steps as described in the first or second aspect of embodiments of the present invention. The computer program product may be a software installation package.

The method and the corresponding device applied to corner transition of the five-axis numerical control machine tool have the advantages that: the transition path determining method for the translational axis and the two linear following methods for the rotating axis provided by the application ensure that the machining tracks of the translational axis and the rotating axis of the five-axis numerical control machine tool have considerable machining precision, geometric continuity and movement smoothness, and solve the problem of corner transition of the five-axis numerical control machine tool.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

FIG. 1 is a schematic diagram of a corner transition method applied to a five-axis numerical control machine;

FIG. 2 is a schematic diagram of a transition path provided by an embodiment of the present invention;

FIG. 3 is a schematic diagram of a curve representing the angle of a rotating shaft according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a curve representing the angle of a rotating shaft according to another embodiment of the present invention;

fig. 5 is a schematic structural diagram of a device applied to corner transition of a five-axis numerical control machine.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It should be apparent that the described embodiments are only some of the embodiments of the present application, and not all embodiments. All other embodiments that can be derived by a person skilled in the art from the embodiments given herein without making any creative effort shall fall within the protection scope of the present application.

The terms "first," "second," "third," and "fourth," etc. in the description and claims of this application and in the accompanying drawings are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "include" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

The five-axis motion relates to motion in two aspects of position and angle, namely compound motion under a space formed by three translational shafts and a space formed by two rotational shafts. The corner transition is realized by inserting transition curves such as broken lines, circular arcs, parameter curves and the like at the joint of adjacent micro straight-line segments, so that the smoothness of a numerical control machining track is realized, the speed of a moving part of a numerical control machine tool passing through a corner is improved, and the machining efficiency and the machining quality are improved. In the corner transition planning of five-axis motion, not only the transition path of the translational axis but also the angle change process of two rotational axes need to be considered.

Fig. 2 and 3 are given for ease of understanding. FIG. 2 shows a transition path 103 of a translational axis based on a position coordinate system and a first linear machining section 101 and a second linear machining section 102. in FIG. 2, point P is the intersection of the two linear machining sections, i.e., the corner apex, Q₀Point is the starting point of the transition, Q₂At the end of the transition, Q₁At the moment, the angle theta is any point on the transition path, and the angle theta is the supplementary angle of the included angle of the two linear machining sections; FIG. 3 is an angle plot of a rotating axis based on an angular coordinate system with the abscissa of the A-axis and the ordinate of the C-axis, or with the abscissa of the C-axis and the ordinate of the A-axis, S₀Is Q₀Corresponding point in the angular coordinate, S₂Is Q₂Corresponding point in the angular coordinate, S₁Is Q₁At the corresponding point in the angle coordinate, R is the corresponding point of P in the angle coordinate, the curve corresponding to the first straight line processing section in FIG. 3 is called the first angle change curve, the curve corresponding to the second straight line processing section is called the second angle change curve, the transition pathThe corresponding curve is referred to as the transition angle profile.

In this embodiment, a transition path is first determined, and the steps are as follows:

s101: acquiring a transition path of the translational axis, wherein the transition path is used for smoothly connecting the first linear machining section and the second linear machining section;

the shape of the transition path is any one of a part of an ellipse, a part of a hyperbola, and a part of a parabola. The two ends of the transition path are respectively tangent to the first linear processing section and the second linear processing section.

The analytic expression of the transition path may be expressed in NURBS (Non-Uniform rational B-Splines). Specifically, the following can be written:

where P is the corner vertex, the position of P is known, Q₀、Q₂U is a parameter of the curve for the transition starting point and the transition end point, and satisfies 0 ≦ u ≦ 1, and ω is called a shape parameter or a shape factor for adjusting the shape of the transition path, satisfies ω>0. In practical application, the shape factor can be adjusted according to requirements when omega>The locus is a part of a hyperbola when 1, a part of a parabola when ω is 1, and a part of an ellipse when 0 < ω < 1.

From the above analytical expressions, if it is necessary to completely determine the transition path, Q needs to be determined₀、Q₂Given the value of ω. Determination of Q₀、Q₂I.e. determining the maximum transition distance of the translational axis. The maximum transition distance needs to follow two conditions: first, the portion of each straight processing path replaced by the transition section, i.e. the PQ in fig. 2, cannot exceed half the original length₀、PQ₂Their length d is the maximum transition distance. Secondly, the transition section is deformed compared with the original track, and the generated contour error is called as a first contour error, namely P and the transition midpoint Q in the lower graph₁The distance delta of, needs to be controlledWithin a certain range. The requirement for profile error may also translate into a requirement for transition distance.

The geometric meaning of the shape parameter omega isPoint H is PQ₁Extension line of and Q₀Q₂From this, the profile error versus transition distance can be derived as follows:

wherein theta is a supplementary angle of an included angle between the first straight line processing section and the second straight line processing section.

From the above expression of the first profile error δ, in combination with the expression of c (u), it can be derived that the step of determining the transition path is:

acquiring a first contour error;

determining a first value of the maximum transition distance according to the first contour error and the shape parameter;

and determining a transition path according to the first value and the analytic expression.

The first contour error is given according to the actual machining precision requirement, and the maximum transition distance can be obtained according to the expression of delta under the condition of giving the first contour error and the shape parameter. For the sake of easy distinction and understanding, the maximum transition distance obtained here is referred to as the first value d₁. Obtaining a first value, i.e. determining Q₀、Q₂According to the expression of C (u), the equation with u as an independent variable can be determined, and the track equation of the transition path is determined.

In interpolation programs for numerical control machining, a current interpolation position is generally determined from a current course, i.e., a relational expression C9s0 of a trajectory with respect to the course is required to be established. However, for partial curve types, it is difficult to establish an analytical relationship of the parameter u and the cumulative length s. Therefore, the total length of the transition section is approximately calculated by adopting the Simpson integration method to carry out binary accumulation; and (3) obtaining a piecewise function u9s0 by utilizing the length and end point conditions of each segment calculated in the Simpson integration process and adopting cubic polynomial fitting, and further obtaining an approximate expression of C(s).

In corner transitions, not only the transition trajectory needs to be planned, but also kinematic constraints, such as maximum velocity, need to be determined. In this embodiment, the method further includes:

determining the maximum curvature of the transition path according to the shape parameters;

from the maximum curvature, the maximum velocity on the path through the transition is calculated.

The curvature of the point on the transition path has an important meaning for speed planning in the interpolation process. When ω is>cos (theta/2), the maximum curvature of the transition at the midpoint Q of the path₁Obtaining; when 0 < omega < cos (theta/2), the maximum curvature is at the transition point Q₀、Q₂Obtaining; when ω is cos (θ/2), the curvature is equal everywhere. The method for calculating the curvature radius at the characteristic points based on the parameter equation C (u) is as follows:

radius of curvature at the midpoint:

radius of curvature at the junction:

assuming that the upper limit of the resultant acceleration of the machine tool translational axis on the corner plane is a, the rate of machining through the transition path should satisfy:

in addition, the curvature is continuously variable over the transition. But at the transfer point Q₀、Q₂The curvature may abruptly change. Therefore, the transition section can completely realize smooth speed of the whole processing process and basically realize processingThe speed is smooth.

After determining the transition path of the translation shaft, determining the angle of the corresponding rotation shaft on the transition path, comprising the following steps:

s102: acquiring a first linear relation and a second linear relation; the first linear relation is the linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the first linear processing section; the second linear relation is the linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the second linear machining section;

s103: and determining the angle of the corresponding rotating shaft on the transition path according to the first linear relation and the second linear relation.

Specifically, in the first linear machining section and the second linear machining section, the XYZ coordinates of the translational axis and the AC coordinates of the rotational axis have a linear following relationship, but the method of the present application is not limited to the machine tool model to which the AC axis is applied, and the machine tool models of the AB and BC axes may be used. For example, the starting point and the end point of the straight line machining section are assumed to be P_s(x_s,y_s,z_s)、P_e(x_e,y_e,z_e) Their corresponding angular coordinate is R_S(a_s,c_S)、R_e(a_e,c_e). Then, for a certain interpolation point P on the processing section_iIts corresponding angular coordinates are:

specifically, for example, every time the translational axis travels 1mm on one of the linear processing sections, the rotation angle of the rotating axis on the a axis is 1 degree, and the rotation angle of the rotating axis on the C axis is 2 degrees; the first linear relationship and the second linear relationship may be the same or different.

From the above description, the first linear machining section and the second linear machining section are known, and in this embodiment, the angular coordinate R of the corner vertex is known, and based on the first linear relationship and the second linear relationship, a first angle variation curve indicating the course of the angle of the rotating shaft on the first linear machining section and a second angle variation curve indicating the course of the angle of the rotating shaft on the second linear machining section can be determined.

After the first angle change curve and the second angle change curve are determined, the transition section angle change curve of the rotating shaft on the transition path is determined according to the first linear relation and the second linear relation.

Specifically, on the transition path, the angle variation of the rotating shaft and the displacement of the translational shaft in the direction of the first linear processing section and the displacement of the translational shaft in the direction of the second linear processing section respectively satisfy the first linear relationship and the second linear relationship, so as to determine the transition section angle variation curve.

And extending the relationship between the rotation angle of the rotating shaft and the stroke length of the translation shaft to a transition path of corner transition. The method comprises the steps of firstly obtaining angle change curves corresponding to two linear machining sections according to the relation, then taking any point on a transition path, decomposing the shortest path from any point of a starting point of the transition section, an end point of the transition section and a vertex of a corner to the any point into two path components along the direction of the two linear machining sections, obtaining corresponding angle change components, namely angle change quantity of a rotating shaft according to the first linear relation and the second linear relation in the direction of the two path components when the stroke length of a translational shaft corresponding to the two path components is known, and determining the angle coordinate of the any point according to the angle coordinate of the vertex of the corner.

In particular, with reference to fig. 2 and 3, the transition path and the two straight processing section curves are determined, i.e. point P, Q₀Dot, Q₁Dot, Q₂The coordinates of the points are known, in this embodiment, the R point is known, and then S can be easily found from the first linear relationship and the second linear relationship₀Dot, S₂Coordinates of the point in an angular coordinate system; and for S₁Point, connection Q₀And Q₁Of course, Q may be connected₁And P or connection Q₁And Q₂Then Q is added₀Q₁Divided into two components Q along two straight processing sections₀E and EQ₁The stroke length of the translational shaft and the angular variation of the rotational shaft have a linear relationship in each component, i.e. Q₀E/S₀F is a fixed value, then the point F corresponding to the point E can be determined in the angle coordinate system, and then the EQ is used for determining the point F₁/FS₁Is a fixed value, then S can be determined₁Position in an angular coordinate system. Similarly, the position in the angular coordinate system can be found for any point on the transition path, and the transition angle profile can be completely determined.

From the above description, in the present embodiment, the analytical expression of the transition path is written as a component synthesis form as follows:

wherein:

the morphology of the angle transitions is defined in the same format, and is analytically expressed as follows:

in an embodiment of the application, the corner transition method further includes:

acquiring a second contour error;

determining a second value of the maximum transition distance according to the second contour error;

taking out the minimum value from the first value, the second value and half of the length of the linear machining section as the final maximum transition distance; the linear processing section comprises at least one of a first linear processing section and a second linear processing section.

In the angle space, the angle change curve obtained by the linear following method is an irregular curve, and therefore the shortest euclidean distance between the point on the irregular curve and the R point, that is, the second profile error is required to be very complicated. Get some S₁The euclidean distance D (0.5) from R is the second profile error, which is finally derived as the second profile error δ_ACThe expression of (a) is:

whereinReferred to as the follow-up rate of the two straight processing sections,is a unit vector in the direction of the two straight processing sections, d₂Is the second value. Since the actual second contour error is always less than or equal to the approximated second contour error represented by the above formula, the approximation method can sufficiently satisfy the requirements of accuracy measurement and error control. From the above equation, given the second profile error δ_3CThe second value d can be obtained₂。

A first value can be obtained through a given first contour error; by giving a second profile error, a corresponding second value can be obtained. In order to meet the requirement of profile errors (a first profile error and a second profile error) in two spaces and the requirement of the length of the maximum transition distance of continuous corner transition (namely the maximum transition distance cannot exceed half of the length of a linear machining section, and the lengths of two linear machining sections are equal), the minimum value of a first value, a second value and half of the length of the linear machining section is taken as a final maximum transition distance d, and a final transition path and a transition section angle change curve are obtained by recalculating according to d by combining the calculation mode.

The kinematic properties under this protocol were analyzed. The scheme can completely ensure the smoothness of the angular speed, but the angular acceleration can be suddenly changed at the switching point. On the transition section, the feed speed is set as v, which is decomposed along two sides of the corner to obtain two components v₀、v₂. Note t₀、t₂Is along Q₀P、PQ₂The unit vector of the direction, the included angle between the resultant velocity and the two components is:

the sine theorem has:

the angular velocity is then:

w＝λ₀|v₀|·τ₀+λ₂|v₂|·τ₂

by combining the above equations with the maximum speed limits of the respective rotating shafts, the feed speed limit condition of an arbitrary point on the transition section can be obtained.

The present application further provides another method of determining an angle of a rotating shaft from a first linear relationship and a second linear relationship, comprising:

determining the angle of a corresponding rotating shaft on an interval path from the transition starting point to the transition middle point according to the first linear relation;

and determining the angle of the corresponding rotating shaft on the section path from the transition midpoint to the transition end point according to the second linear relation.

The method does not change the trajectory shape of the angle, namely the curve of the angle of the rotating shaft adopting the corner transition is the same as that of the rotating shaft not adopting the corner transition, and the curve of the angle of the rotating shaft on the transition path obtained by the method is shown in figure 4. The original linear relation between the angle and the position is maintained before entering the transition path; on the transition path, Q is shown in FIGS. 2 and 4₀Q₁And S₀R corresponds to, Q₁Q₂And RS₂Correspondingly, here Q₁Is the middle point of the transition path, and the angle variation of the rotating shaft on the transition path has a linear relation with the translational axis.

With Q₀、Q₁、Q₂For the dividing point, on each segment, the ratio of the track length of the angle to the track length of the position is respectively:

λ₀is Q₀Angle to position ratio of the path length of the preceding straight machining section, lambda₀₁Is Q₀To Q₁Track length ratio of angle to position of track of segment, lambda₁₂Is Q₁To Q₂Track length ratio of angle to position of track of segment, lambda₂Is Q₂The angle to position trajectory length ratio of the trajectory of the straight machining section following the section.

The expression of the transition section angle change curve is:

wherein tau is₀、τ₂Is along S₀R、RS₂Unit vector of direction, s being cumulative distance traveled, i.e. traversedThe distance from the transition point to the current point represents the total length of the transition segment.

The kinematic properties under this protocol were analyzed. In the process pass Q₀Q₁、Q₁Q₂The changes in angular velocity and angular acceleration, respectively, are continuous. While passing through the demarcation point Q₀、Q₁、Q₂When the angular velocity is too high, the angular velocity changes abruptly. Assuming that the feeding speed is | v |, the corresponding angular velocity is sequentially | v |, on each small segment

w₀＝|v|λ₀·τ₀,w₀₁＝|v|λ₀₁·τ₀,

w₁₂＝|v|λ₁₂·τ₂,w₂＝|v|λ₂·τ₂

Binding w₀₁、w₁₂And the maximum speed limit of each rotating shaft, the feed speed limit condition of the transition section can be obtained.

If the acceleration is | a |, the angular acceleration at the transition section is

Bonding ofAnd the maximum acceleration limit of each rotating shaft, the acceleration limit condition of the transition section can be obtained.

When passing through the three demarcation points, additional attention is also required to the angular acceleration case. Assuming that the actual interpolation period is T, the angular acceleration is approximated as:

it is easy to find that the angular acceleration across the demarcation point has a linear relationship with | v |. Therefore, in order to ensure the machining quality and reduce the impact on the machine tool, the feed speed needs to be reduced before the boundary point is crossed.

According to the description, the method for determining the transition path of the translational axis and the two linear following methods of the rotating axis provided by the application can be obtained, so that the machining tracks of the translational axis and the rotating axis of the five-axis numerical control machine tool have considerable machining precision, geometric continuity and movement smoothness, and the problem of corner transition of the five-axis numerical control machine tool is solved.

The method embodiments according to the embodiments of the present invention are explained in detail above, and an apparatus embodiment according to the present invention is described below.

Referring to fig. 5, fig. 5 is a schematic structural diagram of an apparatus for corner transition of a five-axis numerical control machine tool according to an embodiment of the present invention; as shown in fig. 5, the apparatus is applicable to a machine tool, and may include a first acquisition unit 401, a second acquisition unit 402, and a determination unit 403:

a first obtaining unit 401, configured to obtain a transition path of the translational axis, where the transition path is used to smoothly connect the first linear machining section and the second linear machining section;

a second obtaining unit 402, configured to obtain the first linear relationship and the second linear relationship; the first linear relation is the linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the first linear processing section; the second linear relation is the linear relation between the angle variation of the rotating shaft and the stroke length of the translation shaft on the second linear machining section;

a determining unit 403, configured to determine an angle of the corresponding rotating shaft on the transition path according to the first linear relationship and the second linear relationship.

It should be noted that, in the embodiment of the apparatus of the present invention, the functions of each functional unit of the apparatus applied to corner transition of a five-axis numerical control machine tool and the technical effects that the apparatus can bring are referred to the related description in the above method embodiment, and are not described herein again.

The embodiment of the present invention further provides a computer-readable storage medium, where the computer-readable storage medium may store a program, and when the program is executed, the program may include some or all of the steps of any one of the method embodiments described above.

Embodiments of the present invention also provide a computer program or a computer program product, where the computer program may include instructions that, when executed by a computer, enable the computer to perform some or all of the steps including any one of the method embodiments described above.

In the foregoing embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments.

It should be noted that, for simplicity of description, the above-mentioned method embodiments are described as a series of acts or combination of acts, but those skilled in the art will recognize that the present invention is not limited by the order of acts, as some steps may occur in other orders or concurrently in accordance with the invention. Further, those skilled in the art should also appreciate that the embodiments described in the specification are preferred embodiments and that the acts and modules referred to are not necessarily required by the invention.

In the embodiments provided in the present invention, it should be understood that the disclosed apparatus can be implemented in other manners. For example, the above-described embodiments of the apparatus are merely illustrative, and for example, the above-described division of the units is only one type of division of logical functions, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. The elements of the above device embodiments may or may not be physically separated, and some or all of the elements may be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present invention.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit. The integrated unit may be stored in a computer-readable storage medium if it is implemented in the form of a software functional unit and sold or used as a separate product.

Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and may include several instructions to enable a computer device (which may be a personal computer, a server, a network device, or the like, and may specifically be a processor in the computer device) to execute all or part of the steps of the above methods according to the embodiments of the present invention. Among them, the aforementioned storage medium may include: a U-disk, a removable hard disk, a magnetic disk, an optical disk, a Read-Only Memory (ROM) or a Random Access Memory (RAM), and the like.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.