阅读说明：本技术 一种旋转轴回转中心方向及空间位置测量方法 (Method for measuring direction and spatial position of rotation center of rotating shaft ) 是由 杨小君 訾进锋 梁晨涛 吴平 于 2020-06-12 设计创作，主要内容包括：本发明公开了一种旋转轴回转中心方向及空间位置测量方法,包括以下步骤：S101：将A旋转轴和C旋转轴置于零位,且在C旋转轴的工作台面上安装一个斜面；S102：A旋转轴不动,C旋转轴旋转,通过测距传感器在平面上测量一个点阵,拟合平面方程,然后计算出平面的空间焦点和平面的法线焦点,得出C旋转轴的轴心；S103：C旋转轴不动,A旋转轴旋转,通过测距传感器在平面上测量一个点阵,拟合平面方程,然后计算出平面的空间焦点和平面的法线焦点,得出A旋转轴的轴心；本发明能够测量动件式机床旋转轴的空间位置与几何误差。(The invention discloses a method for measuring the rotation center direction and the spatial position of a rotating shaft, which comprises the following steps: s101: the rotating shaft A and the rotating shaft C are arranged at zero positions, and an inclined plane is arranged on a working table top of the rotating shaft C; s102: the rotation axis A is fixed, the rotation axis C rotates, a lattice is measured on a plane through a distance measuring sensor, a plane equation is fitted, and then a space focus of the plane and a normal focus of the plane are calculated to obtain the axis of the rotation axis C; s103: c, the rotating shaft is fixed, the rotating shaft A rotates, a dot matrix is measured on a plane through a distance measuring sensor, a plane equation is fitted, and then a space focus of the plane and a normal focus of the plane are calculated to obtain the axis of the rotating shaft A; the invention can measure the space position and geometric error of the rotating shaft of the movable machine tool.)

1. A method for measuring the rotation center direction and the space position of a rotating shaft is characterized by comprising the following steps:

s101: the rotating shaft A and the rotating shaft C are arranged at zero positions, and an inclined plane with an inclination angle of 10-30 degrees is arranged on a working table surface of the rotating shaft C;

s102: the rotation axis A is fixed, the rotation axis C rotates at least three times, a rectangular lattice is measured on the inclined plane by using a machine tool distance measuring sensor after each rotation is static, then a space plane equation of at least three inclined planes and the value of a normal vector thereof are fitted through the measured lattice, and a plane intersection point P can be calculated through the information₁Axial to the C axisP₁Andformed hollowThe straight line between the C rotating shaft and the C rotating shaft is the axis of the C rotating shaft;

s103: c, the rotating shaft is fixed, the rotating shaft A rotates at least three times, a rectangular lattice is measured on the inclined plane by using a machine tool distance measuring sensor after each rotation is static, then a space plane equation of at least three inclined planes and the value of a normal vector of the space plane equation are fitted through the measured lattice, and a plane intersection point P can be calculated through the information₂Axial to the A axisP₂Andthe formed space straight line is the axis of the rotating shaft A;

wherein the A rotating shaft performs rotating motion around the axis of the X shaft; the C rotating shaft is installed on the A rotating shaft and integrally and simultaneously rotates along with the A rotating shaft, and when the A rotating shaft is located at 0 degree, the C rotating shaft rotates around the axis of the Z shaft.

2. The method as claimed in claim 1, wherein the plane equation and the normal vector of the plane are determined in step S102

the space plane coefficients A, B, C, D satisfy equation X_iA+Y_iB+Z_iC + D is 0(i is less than or equal to m, and m is more than or equal to 4), wherein (X)_i,Y_i,Z_i) For the spatial coordinates of each point in the rectangular lattice, the plane equation coefficients A, B, C, D are obtained by solving the least squares solution of the following linear equation set, and the normal vector of the plane is obtained

3. the method as claimed in claim 2, wherein in step S102, at least three inclined planes are formed according to the plane equation X_iA+Y_iB+Z_iC + D is 0, and the normal vectors of the plane intersection point and the respective plane are calculated

the intersection point of the spatial planes is obtained by solving the least square solution of the linear equation system.

4. The method as claimed in claim 3, wherein in step S102, at least three normal vectors are passedCalculating the axial direction of the C-axis

make the axial unit vector of the rotating shaft

order to

it is known that

solving the least squares solution of the above equations to obtain

5. the method as claimed in claim 1, wherein the step S103 is performed by calculating the plane intersection point P₂Axial to the A axisAnd calculating the plane intersection point P in S102₁Axial to the C axis

6. The method as claimed in claim 1, wherein the zero positions of the a-axis and the C-axis are reference-positioned by a point laser ranging sensor in step S101.

7. The method as claimed in claim 1, wherein the rotation range of the C-axis is 0 ° to 360 ° in step S102.

8. The method as claimed in claim 1, wherein the rotation range of the C-axis is-45 ° to 45 ° in step S103.

Technical Field

The invention relates to the field of laser processing, in particular to a method for measuring the rotation center direction and the spatial position of a rotating shaft.

Background

The beam scanning module of the laser processing equipment adopts non-contact processing, so that laser directly acts on the surface of a workpiece, and the laser processing equipment has the characteristics of small heat influence, flexible processing, wide material and the like.

The movable measuring device is internally provided with three linear shafts X, Y, Z and two rotating shafts A, C, the light beam scanning module and the point laser ranging sensor are arranged on the Z shaft and perform linear motion along with the Z shaft, and the processing table surface is parallel to the rotating plane of the C shaft.

When the machining position and the machining direction vector are known, the attitude of each axis of the machine tool to be machined can be obtained by simple calculation assuming that the axis of each rotating axis completely coincides with the theoretical axis, but since the axis of the rotating axis inevitably has a certain error during the assembly of the machine tool, the position and the direction of the axis of the rotating axis of the machine tool need to be measured, and the machining attitude needs to be analyzed under known conditions to calculate the position of each axis of the machine tool.

Disclosure of Invention

The invention provides a method for measuring the rotation center direction and the spatial position of a rotating shaft, which can measure the rotation center position of the rotating shaft of a movable machine tool relative to the zero point of a distance measuring sensor of the machine tool and the axial direction of the rotating shaft in a machine tool coordinate system.

To achieve these objects and other advantages in accordance with the purpose of the invention, there is provided a rotation axis rotation center direction and spatial position measuring method including the steps of:

s101: the rotating shaft A and the rotating shaft C are arranged at zero positions, and an inclined plane with an inclination angle of 10-30 degrees is arranged on a working table surface of the rotating shaft C;

s102: the rotation axis A is fixed, the rotation axis C rotates for multiple times, a rectangular lattice is measured on the inclined plane by using a machine tool distance measuring sensor after each rotation is static, then a space plane equation of a plurality of inclined planes and values of normal vectors of the space plane equation are fitted through the measured lattice, and the space plane equation is obtained through the fitting of the measured latticeThe plane intersection point P can be calculated by the above information₁Axial to the C axis

P₁And

the formed space straight line is the axis of the C rotating shaft;

s103: c, the rotating shaft is fixed, the rotating shaft A rotates for multiple times, a rectangular lattice is measured on the inclined plane by using a machine tool distance measuring sensor after each rotation is static, then space plane equations of a plurality of inclined planes and values of normal vectors of the space plane equations are fitted through the measured lattice, and a plane intersection point P can be calculated through the information₂Axial to the A axisP₂Andthe formed space straight line is the axis of the rotating shaft A;

wherein the A rotating shaft performs rotating motion around the axis of the X shaft; the C rotating shaft is installed on the A rotating shaft and integrally and simultaneously rotates along with the A rotating shaft, and when the A rotating shaft is located at 0 degree, the C rotating shaft rotates around the axis of the Z shaft.

Further, in the step S102, the plane equation and the normal vector of the plane thereof

The calculation method of (2) is as follows:

the space plane coefficients A, B, C, D satisfy equation X_iA+Y_iB+Z_iC + D is 0(i is less than or equal to m, and m is more than or equal to 4), wherein (X)_i,Y_i,Z_i) For the spatial coordinates of each point in the rectangular lattice, the plane equation coefficients A, B, C, D are obtained by solving the least squares solution of the following linear equation set, and the normal vector of the plane is obtained

Namely (A, B, C);

further, in step S102, at least three slopes are according to the plane equation X_iA+Y_iB+Z_iC + D is 0, and the normal vectors of the plane intersection point and the respective plane are calculatedThe calculation method of the plane intersection point is as follows:

the intersection point of the spatial planes is obtained by solving the least square solution of the linear equation system.

Further, in step S102, at least three normal vectors are passed

Calculating the axial direction of the C-axis

The calculation method is as follows:

make the axial unit vector of the rotating shaft

Expressing, unit vector for each plane normal vectorIs shown, wherein, due toIs obtained by rotating the same plane around a rotating shaftAnd optionallyIncluded angles are equal becauseAnd

are all unit vectors (length 1), i.e.Is provided withAndthe included angle is α degrees and the included angle is α degrees,

andmultiplication of phase pointsFor any i (i is less than or equal to n, n is more than or equal to 3), the following can be obtained:

order to

Wherein

And

for the same direction vector, we can obtain:

it is known that

Has a value of (A)_Ni,B_Ni,C_Ni) Is provided withIs (X, Y, Z), the following linear system of equations can be established:

solving the least squares solution of the above equations to obtain

Will be provided withAnd (3) performing unitization treatment, wherein the obtained unit vector is the axial direction of the rotating shaft:

further, the plane intersection point P is calculated in the step S103₂Axial to the A axis

And calculating the plane intersection point P in S102₁Axial to the C axisThe calculation method is the same.

Preferably, in step S101, the zero positions of the a and C rotation axes are reference-positioned by a point laser ranging sensor.

Preferably, in step S102, the number of rotations of the C rotation shaft is not less than three.

Preferably, in step S102, the rotation range of the C rotation axis is 0 ° to 360 °.

Preferably, in step S103, the number of rotations of the a rotation axis is not less than three.

Preferably, in step S103, the rotation range of the C rotation axis is-45 to 45.

Compared with the prior art, the invention can calculate the rotation center position of each rotating shaft relative to the zero point of the distance measuring sensor of the machine tool and the axial direction of the rotating shaft in the coordinate system of the machine tool through the plane equation of the lattice fitting of the planes under different angles, and can calculate the attitude of each shaft of the machine tool when the five-shaft machine tool processes any point in the machine tool through the rotation center of the rotating shaft and the axial direction of the rotating shaft in the coordinate system of the machine tool.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Drawings

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

FIG. 1 is a schematic flow chart of one embodiment of the present invention.

Detailed Description

The present invention is further described in detail below with reference to the attached drawings so that those skilled in the art can implement the invention by referring to the description text.

It will be understood that terms such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof.

The invention provides a method for measuring the rotation center direction and the space position of a rotating shaft, which comprises the following steps as shown in figure 1:

s101: firstly, the rotating shaft A rotates around the axis of the shaft X; the C rotating shaft is arranged on the A rotating shaft and integrally rotates along with the A rotating shaft at the same time, and when the A rotating shaft is positioned at 0 degree, the C rotating shaft rotates around the axis of the Z shaft;

then, the rotating shaft A and the rotating shaft C are arranged at zero positions, and an inclined plane with an inclination angle of 10-30 degrees is arranged on a working table surface of the rotating shaft C; and the zero positions of the rotating shaft A and the rotating shaft C are subjected to reference positioning by a point laser ranging sensor.

S102: the rotating shaft A is fixed, the rotating shaft C rotates for multiple times, a rectangular lattice is measured on the inclined plane by using a machine tool distance measuring sensor after each rotation is static, and then a space plane equation of a plurality of inclined planes is fitted through the measured lattice. Wherein the spatial plane equation is of the form A_ix+B_iy+C_iz+D_i0, (i ≦ n, n ≧ 3), where the plane normal vector

Has a value of (A)_i,B_i,C_i) Calculating the spatial intersection point P of the above planes₁And the axial direction of the C axis can be calculated through the normal vector of the planeP₁Andthe spatial straight line is the axis of the C rotating shaft, i.e. P₁The position of the rotation center of the C rotating shaft relative to the zero point of the distance measuring sensor of the machine tool,the axial direction of the rotating shaft C under the machine tool coordinate system; the number of rotations of the C-axis is not less than three, and the rotation range of the C-axis is 0-360 deg.

S103: and C, the rotating shaft is fixed, the rotating shaft A rotates for multiple times, a rectangular lattice is measured on the inclined plane by using a machine tool distance measuring sensor after each rotation is static, and then a space plane equation of a plurality of inclined planes is fitted through the measured lattice. Wherein the space is flatThe form of the surface equation is A_jx+B_jy+C_jz+D_j0, (j is less than or equal to n, n is more than or equal to 3), wherein the normal vector of the plane

Has a value of (A)_j,B_j,C_j) Calculating the spatial intersection point P of the above planes₂And the axial direction of the A axis can be calculated through the normal vector of the planeP₂Andthe spatial straight line is the axial center of the rotating shaft A, namely P₂The position of the revolution center of the rotating shaft A relative to the zero point of the distance measuring sensor of the machine tool,

is the axial direction of the rotating shaft A under a machine tool coordinate system; the rotating frequency of the rotating shaft A is not less than three times, and the rotating range of the rotating shaft C is-45 degrees.

Wherein the A rotating shaft performs rotating motion around the axis of the X shaft; the C rotating shaft is installed on the A rotating shaft and integrally and simultaneously rotates along with the A rotating shaft, and when the A rotating shaft is located at 0 degree, the C rotating shaft rotates around the axis of the Z shaft.

In the step S103, the plane intersection point P is calculated₂Axial to the A axisAnd calculating the plane intersection point P in S102₁Axial to the C axisThe method for calculating the plane equation by the rectangular lattice is as follows, so that only the step S102 is taken as an example for explanation:

the space plane coefficients A, B, C, D satisfy equation X_iA+Y_iB+Z_iC+D＝0(iM is less than or equal to m, m is more than or equal to 4), wherein (X)_i,Y_i,Z_i) For the spatial coordinates of each point in the rectangular lattice, the plane equation coefficients A, B, C, D are obtained by solving the least squares solution of the following linear equation set, and the normal vector of the plane is obtainedThe value of (A, B, C);

sequentially measuring A, C rectangular lattices on n (n is more than or equal to 3) planes of a rotating shaft under different angles and calculating a plane equation, wherein n (n is more than or equal to 3) planes have unique intersection points under ideal conditions, and the method for calculating the plane intersection points comprises the following steps:

the point in space satisfying n (n is more than or equal to 3) space plane equations is the intersection point of the n (n is more than or equal to 3) space planes, and the space plane equation is A_ix+B_iy+C_iz+D_i0, (i is not more than n, n is not less than 3), and the intersection point of the space plane can be obtained by solving the least square solution of the following linear equation set;

and, a normal vector passing through the above plurality of spatial planesThe axial direction of the rotating shaft can be calculated as follows:

make the axial unit vector of the rotating shaft

Expressing, unit vector for each plane normal vectorTherein, are shown. Due to the fact thatIs obtained by rotating the same plane around a rotating shaftAnd optionallyIncluded angles are equal becauseAndare all unit vectors (length 1), i.e.Is provided withAndthe included angle is α degrees and the included angle is α degrees,

andmultiplication of phase points

For any i (i is less than or equal to n, n is more than or equal to 3), the following can be obtained:

order toWhereinAnd

for the same direction vector, we can obtain:

it is known thatHas a value of (A)_Ni,B_Ni,C_Ni) Is provided with

Is (X, Y, Z), the following linear system of equations can be established:

solving the least squares solution of the above equations to obtain

Will be provided withAnd (3) performing unitization treatment, wherein the obtained unit vector is the axial direction of the rotating shaft:

the invention also provides an embodiment, and the measuring method comprises the following steps:

s201: the rotating shaft A and the rotating shaft C are arranged at zero positions, the reference positioning is carried out by a point laser ranging sensor, and an inclined plane with an inclination angle of 10-30 degrees is arranged on a working table top of the rotating shaft C;

s202: the rotating shaft A is fixed, and the rotating shaft C rotates six times, respectively 6Measuring a rectangular lattice on the inclined plane by using a machine tool ranging sensor after rotating and standing at each time, and then fitting a space plane equation of six inclined planes through the measured lattice, wherein the space plane equation is in the form of A_ix+B_iy+C_iz+D_i0, (i ≦ 6), where the plane normal vectorHas a value of (A)_i,B_i,C_i) Calculating the spatial intersection point P of the above six planes₁And the axial direction of the C axis can be calculated through the normal vector of the plane

P₁Andthe spatial straight line is the axis of the C rotating shaft, i.e. P₁The position of the rotation center of the C rotating shaft relative to the zero point of the distance measuring sensor of the machine tool,

the axial direction of the rotating shaft C under the machine tool coordinate system;

s203: the C rotating shaft is not moved, the A rotating shaft rotates for seven times, the rotation angles are respectively 0 degrees, 15 degrees, 30 degrees, 45 degrees, 15 degrees, 30 degrees and 45 degrees, a rectangular dot matrix is measured on the inclined plane by using a machine tool distance measuring sensor after each rotation and rest, and the form of the space plane equation is A_jx+B_jy+C_jz+D_j0, (j is less than or equal to n, n is more than or equal to 3), wherein the normal vector of the planeHas a value of (A)_j,B_j,C_j) Calculating the spatial intersection point P of the above seven planes₂And the axial direction of the A axis can be calculated through the normal vector of the plane

P₂Andthe spatial straight line is the axial center of the rotating shaft A, namely P₂The position of the revolution center of the rotating shaft A relative to the zero point of the distance measuring sensor of the machine tool,is the axial direction of the A rotating shaft under the coordinate system of the machine tool.

And finally, calculating the processing attitude of the workpiece according to the axis of the A shaft and the axis of the C shaft obtained in the steps S202 and S203.

While embodiments of the invention have been disclosed above, it is not limited to the applications listed in the description and the embodiments. It can be applied to all kinds of fields suitable for the present invention. Additional modifications will readily occur to those skilled in the art. It is therefore intended that the invention not be limited to the exact details and illustrations described and illustrated herein, but fall within the scope of the appended claims and equivalents thereof.