Machining, positioning and adjusting method for H-shaped steel machine tool

Abstract

The invention discloses an H-shaped steel machine tool machining positioning adjusting method, and belongs to the technical field of H-shaped steel machine tool machining. The H-shaped steel machine tool machining positioning adjusting method comprises the steps that a linear array CCD camera is installed on a machine tool workbench, and the data acquisition range of the linear array CCD camera is adjusted through a high-precision rotary table; after shooting is completed, data are transmitted to a computer to form point cloud data of the H-shaped steel, the computer carries out splicing processing on combined point coordinate values through an ICP point cloud splicing algorithm, the contour line of the H-shaped steel is determined through a weighted least square linear fitting algorithm, and finally the included angle and the moving distance between the center line and the X axis of the machine tool workbench in the horizontal direction are determined. The adjustment of the H-shaped steel is realized. By adjusting the offset E and the deflection angle theta, the center line of the large H-shaped steel is consistent with the center line of a machine tool, double-side equal-machining-amount cutting can be conveniently achieved, great convenience is provided for machining programming, meanwhile, tool abrasion in the double-side milling process can be controlled to be basically consistent, and the shutdown tool changing time is shortened.

Description

Technical Field

[0001] The invention belongs to the technical field of H-beam machine tool processing, and in particular relates to a H-beam machine tool processing positioning adjustment method. Background Art

[0002] With the continuous development of my country's offshore oil, natural gas and other resources, the increasing demand for energy has urgently required my country to carry out revolutionary innovation and technological advancement in the field of marine engineering equipment. Large offshore oil and gas platforms require a large number of steel structure modules during construction, and a large number of large H-shaped steels are used in the production of steel structure modules. Large H-shaped steels are generally welded parts, and there are defects such as bumps, bends, and burrs on the edges and corners of the flange plates. If they are not repaired before spraying, the spraying quality of the H-shaped steel will be greatly affected. The traditional method of flange plate grinding is manual hand-held angle grinder grinding, which is not only inefficient and has high labor costs, but also dangerous. Large steel flange plates need to be machined for better spraying operations.

[0003] Large H-shaped steel is usually several meters or even more than ten meters long. It is hoisted or rolled onto machine tools. To facilitate machining, the position of the H-shaped steel needs to be adjusted. Traditional tape measurements are not only inefficient and inaccurate, but also require tedious manual calculations.

[0004] Therefore, it is urgent to design a H-beam machine tool processing positioning adjustment method to solve the above-mentioned problems. Summary of the invention

[0005] The purpose of the present invention is to provide a method for positioning and adjusting H-beam machine tool processing, which is convenient for realizing equal processing volume cutting on both sides, provides great convenience for processing programming, and at the same time can control the tool wear in the bilateral milling process to be basically consistent, with the advantage of less downtime for tool changing, thus solving the problems mentioned in the background technology.

[0006] To achieve the above purpose, the specific technical solution of the H-beam machine tool processing positioning adjustment method of the present invention is as follows:

[0007] A method for positioning and adjusting H-beam machine tool processing, comprising the following steps:

[0008] S1. Place the H-shaped steel on the machine tool workbench, install standard measuring points on the upper and lower sides of the machine tool workbench, marked as P1 and P2, and install standard measuring points on the front and back sides of the machine tool workbench, marked as P3 and P4;

[0009] S2. A machine tool column is installed on the machine tool workbench, and a CCD camera is arranged on the machine tool column. The CCD camera can be rotated relative to the machine tool workbench to change the shooting angle of the CCD camera;

[0010] S3. Establish a coordinate system XOY, with the installation point of the machine column as the origin O, the center line of the length direction of the machine table as the X axis, the width direction as the Y axis, and the center line of the machine column as the Z axis;

[0011] S4, measuring the installation height H0 of the CCD camera, the length L of the H-shaped steel, the width W of the H-shaped steel and the height H of the H-shaped steel;

[0012] S5, adjust the data acquisition range of the CCD camera, set the standard measuring point P1 as the starting point of the up and down shooting, set the standard measuring point P2 as the end point of the up and down shooting, set the standard measuring point P3 as the starting point of the front and back shooting, and set the standard measuring point P4 as the end point of the front and back shooting;

[0013] S6. Set the angular velocity of the CCD camera to The angular velocity of one rotation back and forth is Set the shooting path of the CCD camera. The up-down shooting path is from the standard measuring point P1 to the standard measuring point P2, and the front-back shooting path is from the standard measuring point P3 to the standard measuring point P4.

[0014] S7, when the CCD camera is aimed at the initial point P1 shooting position, the angular velocity Take pictures along the up and down shooting path. When the CCD camera is aimed at the initial point P3 shooting position, the angular velocity Take pictures along the front and back shooting paths, and store the data in a computer after the pictures are taken;

[0015] S8, performing pixel point cloud preprocessing on the obtained image, selecting points on the outer edge of the H-beam on the image as image stitching points, and calculating the coordinate values ​​of the H-beam image merging points on the image based on the imaging principle of the CCD camera;

[0016] S9. Using the ICP point cloud stitching algorithm in a computer to stitch the coordinate values ​​of the merged points, and then performing point cloud data denoising to form point cloud data of the H-beam;

[0017] S10, performing linear fitting on the complete H-beam point cloud data obtained in S7 by using a weighted least squares linear fitting algorithm to obtain contour lines L1, L2, L3 and L4 of the H-beam;

[0018] S11, according to the length and width of the H-beam, L1 and L3 are selected as the reference, and the center point of the contour line of the H-beam is retrieved by the nearest neighbor search method within the radius R. After the center point is determined, the weighted least squares linear fitting algorithm is used again to obtain the center line L0 of the H-beam contour;

[0019] S12, calculate the coordinate value O1 (x) of the intersection value based on the center line L0 of the H-beam profile and the H-beam profile lines L2 and L4o1 ,y o1 , H) and O2(x o2 ,y o2 , H), calculate the angle with the horizontal X-axis according to the coordinate value of the intersection point, which is the deflection angle, recorded as θ, and the offset E of the left end point from the horizontal axis. The calculation formula is as follows:

[0020]

[0021] Where E is the offset of the endpoint from the horizontal axis, θ is the deflection angle, and the angle between the intersection coordinate value and the horizontal X-axis is calculated;

[0022] S13. Adjust the H-beam according to the offset E and the deflection angle θ. First, translate the left end point on the center line of the H-beam by an offset E, and then rotate the axis of the H-beam by θ so that the center line is always aligned with the center line of the machine tool worktable.

[0023] Furthermore, in S2, a turntable is installed on the machine tool column, and the turntable is used to install the CCD camera. The turntable can rotate relative to the machine tool worktable to change the shooting angle of the CCD camera.

[0024] Furthermore, in S4, a laser measuring instrument is used for measurement.

[0025] Further, in S5, when the CCD camera can capture point P1, the angle between the shooting angle at this time and the axis Z is marked as α1, when the CCD camera can capture point P2, the angle between the shooting angle at this time and the axis Z is marked as α2, when the CCD camera can capture point P3, the angle between the shooting angle at this time and the axis Z is marked as β1, and when the CCD camera can capture point P4, the angle between the shooting angle at this time and the axis Z is marked as β2.

[0026] Further, in S8, point P on the outer edge of the H-beam on the image i , P i+1 , P i+2 and P i+3 is the image stitching point.

[0027] Further, S8 comprises the following steps:

[0028] S81. Determine the H-beam image stitching point P i , P i+1 , P i+2 and P i+3 location;

[0029] S82. Calculate the upper and lower corners of each splicing point and front and rear corners

[0030] In the formula, m is the number of times the high-precision turntable rotates up and down, and n is the number of times the high-precision turntable rotates forward and backward;

[0031] S83, calculate the image splicing point P from the focus of the CCD camera to the H-beam according to the imaging principle of the CCD camera. i The distance L i , the formula is:

[0032] L i =f i ·H / H0i=1,2,3...

[0033] Where, L i is the distance from the focus of the CCD camera to the image stitching point on the H-beam, f i is the focal length of the CCD camera at the i-th shooting, H is the height of the steel section, H0 is the installation height of the CCD camera, and i is the sequence number at the i-th shooting;

[0034] S84, based on the distance L from the CCD camera focus to the image stitching point on the H-beam i And the upper and lower rotation angle α i and the front-to-back angle β i Calculate the coordinate value of the image merging point Pi, the calculation formula is:

[0035] P i =(L i sinα i cosβ i , L i sinα i sinβ i , H)

[0036] Where, P i is the coordinate of the merging point, L i is the distance from the CCD camera focus to the image stitching point on the H-beam, α i is the angle of the CCD camera turning up and down, β i is the forward and backward rotation angle of the CCD camera, and H is the height of the steel section.

[0037] Further, S9 includes the following steps:

[0038] S91. Set the critical angle ρ in the computer th , stitching error d', select the point cloud data of any two adjacent images as the point cloud data to be merged, A is the target point cloud data, and B is the stitching point cloud data;

[0039] S92, randomly select three points P in the target point cloud data A i , P i+1 , P i+2Construct a plane QA, and draw the normal η of the plane through any point pi ;

[0040] S93. Pick any three points Q in the spliced ​​point cloud data B. i , Q i+1 , Q i+2 Construct a plane and draw the normal η of the plane through one point Qi ;

[0041] S94, calculate normal η pi With normal η Qi If the angle ρ is greater than the set critical angle ρ th , then return to S93 and reselect any three points in the spliced ​​point cloud data B as the normal line η of the plane Qi , until the normal η pi With normal η Qi The angle ρ between them is less than or equal to the set critical angle ρ th , record the plane at this time as Q v ;

[0042] S95, through plane Q v Different points on the plane Q A Draw perpendicular lines with distances d1, d2, ...d 1+v , determine the minimum distance, d iv =min(d1, d2…d 1+v ), and according to the minimum distance d iv Determine the coordinates d of the corresponding foot of the perpendicular iv (x iv ,y iv );

[0043] S96, according to different vertical foot coordinate values ​​d iv (x iv ,y iv ) to find the rotation angle R and translation distance t, the calculation formula is:

[0044]

[0045] Where f(R,t) is a function of the rotation angle R and the translation distance t, R is the rotation angle, t is the translation distance, k is the number of the nearest point pairs on the plane Qv, and x_iv and y_iv are the perpendicular foot coordinate values;

[0046] S97, translating and rotating the spliced ​​point cloud data set B according to the rotation angle R and the translation distance t to obtain a new corresponding point cloud set B';

[0047] S98. Make a plane Q through the points on the new corresponding point cloud set B' AThe perpendicular line of the point is used to calculate the distance D from the point to the plane. i , according to the distance D i Calculate the average distance D between the new corresponding point cloud set B' and the target point set A 平均 ;

[0048]

[0049] Where D 平均 is the average distance, D i Q is the point to plane A The distance, N is the number of points;

[0050] S99, if D 平均 If the error is less than the set splicing error d', the iteration stops, otherwise it returns to S95 until the termination condition D is met. 平均 Less than the set splicing error d';

[0051] S910, updating the spliced ​​point cloud data to target point cloud data A, updating the reselected point cloud data to spliced ​​point cloud data B, and returning to S91 to splice the point cloud data of the H-beam until all the image point cloud data are spliced ​​to obtain all the point cloud data of the H-beam;

[0052] S911, denoise all point cloud data of H-beam after splicing. X -R≤X i ≤L X +L+R, -W / 2-T≤Y i The point cloud data within the range of ≤W / 2+T are retained, and those beyond the range are eliminated. After the elimination is completed, the complete H-beam point cloud data is obtained;

[0053] Where R is the allowable reserved value in the length direction, and T is the allowable reserved value in the width direction. The reserved value size is set in the computer according to requirements.

[0054] Further, S10 includes the following steps:

[0055] S101, set each point cloud data P of H-beam i The weight coefficient ω i ;

[0056]

[0057] In the formula, ω i is the point cloud data weight system, x i It is the horizontal x-coordinate value of the point cloud data;

[0058] S102. Construct the least square linear fitting function of the H-beam contour line:

[0059]

[0060] In the formula, l i is the H-beam contour function, a is the function slope, b is the intercept, n is the number of fitting points, x i ,y i are the coordinate values ​​of the fitting points.

[0061] S103, calculate the a and b values ​​of the weighted least squares linear fitting algorithm function of the H-beam contour line

[0062]

[0063] S104. Repeat S102 and S103 to calculate the contour lines of the H-shaped steel, which are marked as L1, L2, L3 and L4 respectively.

[0064] Furthermore, in S11, an Octree search algorithm is used for retrieval.

[0065] Furthermore, the search radius of the Octree search algorithm is R=W / 2.

[0066] The present invention has the following advantages: through the CCD camera installed on the processing machine tool, the CCD camera obtains the deflection angle between the center line of the large H-shaped steel and the axis of the machine tool movement axis, and the offset between the center line of the large H-shaped steel and the center line of the machine tool. Through the adjustment of these two parameters, the center line of the large H-shaped steel and the axis of the machine tool movement axis are made to coincide with each other, and at the same time, the center line of the large H-shaped steel is consistent with the center line of the machine tool, which can conveniently realize bilateral equal processing amount cutting, provide great convenience for processing programming, and at the same time can control the tool wear in the bilateral milling process to be basically consistent, thereby reducing the downtime time for tool changing. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 It is a schematic flow chart of the processing positioning adjustment method of the present invention;

[0068] Figure 2 It is a front view of the measurement structure of the CCD camera of the present invention;

[0069] Figure 3 A top view of the measurement structure of the CCD camera of the present invention;

[0070] Figure 4 This is a schematic diagram of measuring the splicing points of H-beams by CCD photography of the present invention;

[0071] Figure 5 It is a schematic diagram of the outline of the H-shaped steel structure of the present invention;

[0072] Markings in the figure: 1. Machine tool worktable; 2. Machine tool column; 3. Turntable; 4. CCD camera; 5. Standard measuring point; 6. H-beam. DETAILED DESCRIPTION

[0073] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0074] Those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present invention and form different embodiments. For example, in the claims, any one of the claimed embodiments may be used in any combination.

[0075] Please refer to the attached Figure 1 To Attachment Figure 5 The invention describes an H-beam machine tool processing positioning adjustment method.

[0076] At present, large H-shaped steels are generally several meters or even more than ten meters long. They are hoisted or rolled onto machine tools. In order to facilitate mechanical processing, the position of the H-shaped steels needs to be adjusted. Traditional tape measures are not only inefficient and inaccurate, but also require tedious manual calculations.

[0077] Therefore, the H-beam machine tool processing positioning adjustment method includes the following steps:

[0078] S1. Place the H-shaped steel 6 on the machine tool workbench 1, install standard measuring points 5 on the upper and lower sides of the machine tool workbench 1, marked as P1 and P2, and install standard measuring points 5 on the front and rear sides of the machine tool workbench 1, marked as P3 and P4;

[0079] S2. A machine tool column 2 is installed on the machine tool worktable 1. A CCD camera 4 is provided on the machine tool column 2. The CCD camera 4 can rotate relative to the machine tool worktable 1 to change the shooting angle of the CCD camera 4.

[0080] Specifically, a turntable 3 is installed on the machine tool column 2 , and the CCD camera 4 is installed on the turntable 3 . The turntable 3 can rotate relative to the machine tool worktable 1 to change the shooting angle of the CCD camera 4 .

[0081] Preferably, the turntable 3 is a high-precision turntable 3, which can drive the CCD camera 4 to rotate forward and backward, and can also drive the CCD camera 4 to rotate up and down.

[0082] Specifically, the CCD camera 4 is a linear array CCD camera.

[0083] S3, establish a coordinate system XOY, with the installation point of the machine tool column 2 as the origin O, the center line of the length direction of the machine tool worktable 1 as the X axis, the width direction as the Y axis, and the center line of the machine tool column 2 as the Z axis;

[0084] S4, measuring the installation height H0 of the CCD camera 4, the length L of the H-shaped steel 6, the width W of the H-shaped steel 6 and the height H of the H-shaped steel 6;

[0085] Specifically, a laser measuring instrument is used for measurement. In other embodiments of the present invention, other measuring instruments may also be used for measurement.

[0086] S5, adjust the data acquisition range of the CCD camera 4, set the standard measuring point 5P1 as the starting point of the up and down shooting, set the standard measuring point 5P2 as the end point of the up and down shooting, set the standard measuring point 5P3 as the starting point of the front and back shooting, and set the standard measuring point 5P4 as the end point of the front and back shooting;

[0087] Specifically, when the CCD camera 4 can capture point P1, mark the angle between the shooting angle at this time and the axis Z as α1; when the CCD camera 4 can capture point P2, mark the angle between the shooting angle at this time and the axis Z as α2; when the CCD camera 4 can capture point P3, mark the angle between the shooting angle at this time and the axis Z as β1; and when the CCD camera 4 can capture point P4, mark the angle between the shooting angle at this time and the axis Z as β2.

[0088] S6, set the angular velocity of the CCD camera 4 to rotate up and down once The angular velocity of one rotation back and forth is The shooting path of the CCD camera 4 is set, the up-down shooting path is from the standard measuring point 5P1 to the standard measuring point 5P2, and the front-back shooting path is from the standard measuring point 5P3 to the standard measuring point 5P4;

[0089] S7, when the CCD camera 4 is aimed at the initial point P1 to shoot the position, the angular velocity Take pictures along the up and down shooting path. When the CCD camera 4 is aimed at the initial point P3 shooting position, the angular velocity Take pictures along the front and back shooting paths, and store the data in a computer after the pictures are taken;

[0090] S8, performing pixel point cloud preprocessing on the obtained image, selecting points on the outer edge of the H-beam 6 on the image as image stitching points, and calculating the coordinate values ​​of the image merging points of the H-beam 6 on the image according to the imaging principle of the CCD camera 4;

[0091] Specifically, point P on the outer edge of the H-beam 6 on the image i , Pi+1 , P i+2 and P i+3 is the image stitching point;

[0092] S8 includes the following steps:

[0093] S81, determine the H-beam 6 image stitching point P i , P i+1 , P i+2 and P i+3 location;

[0094] S82. Calculate the upper and lower corners of each splicing point and front and rear corners

[0095] Wherein, m is the number of times the high-precision turntable 3 rotates up and down, and n is the number of times the high-precision turntable 3 rotates forward and backward;

[0096] S83, according to the imaging principle of the CCD camera 4, calculate the image splicing point P from the focus of the CCD camera 4 to the H-beam 6 i The distance L i , the formula is:

[0097] L i = f i·H / H0 i=1,2,3...

[0098] Where, L i is the distance from the focus of CCD camera 4 to the image stitching point on H-beam 6, f i is the focal length of the CCD camera 4 at the i-th shooting, H is the height of the steel section, H0 is the installation height of the CCD camera 4, and i is the sequence number at the i-th shooting;

[0099] S84, based on the distance L from the focus of the CCD camera 4 to the image stitching point on the H-beam 6 i And the upper and lower rotation angle α i and the front-to-back angle β i Calculate the coordinate value of the image merging point Pi, the calculation formula is:

[0100] P i =(L i sinα i cosβ i , L i sinα i sinβ i , H)

[0101] Where, P i is the coordinate of the merging point, L i is the distance from the focus of CCD camera 4 to the image stitching point on H-beam 6, αi is the angle of the CCD camera 4 rotating up and down, β i is the angle of the CCD camera 4 rotating forward and backward, and H is the height of the steel section.

[0102] S9, in a computer, the coordinate values ​​of the merged points are spliced ​​by using an ICP point cloud splicing algorithm, and then point cloud data denoising is performed to form point cloud data of the H-beam 6;

[0103] S9 includes the following steps:

[0104] S91. Set the critical angle ρ in the computer th , stitching error d', select the point cloud data of any two adjacent images as the point cloud data to be merged, A is the target point cloud data, and B is the stitching point cloud data;

[0105] S92, randomly select three points P in the target point cloud data A i , P i+1 , P i+2 Construct a plane QA, and draw the normal η of the plane through any point pi ;

[0106] S93. Pick any three points Q in the spliced ​​point cloud data B. i , Q i+1 , Q i+2 Construct a plane and draw the normal η of the plane through one point Qi ;

[0107] S94, calculate normal η pi With normal η Qi If the angle ρ is greater than the set critical angle ρ th , then return to S93 and reselect any three points in the spliced ​​point cloud data B as the normal line η of the plane Qi , until the normal η pi With normal η Qi The angle ρ between them is less than or equal to the set critical angle ρ th , record the plane at this time as Q v ;

[0108] S95, through plane Q v Different points on the plane Q A Draw perpendicular lines with distances d1, d2, ...d 1+v , determine the minimum distance, d iv =min(d1, d2…d 1+v ), and according to the minimum distance d iv Determine the coordinates d of the corresponding foot of the perpendicular iv (x iv ,y iv );

[0109] S96, according to different vertical foot coordinate values ​​d iv (x iv ,y iv ) to find the rotation angle R and translation distance t, the calculation formula is:

[0110]

[0111] Where f(R,t) is a function of the rotation angle R and the translation distance t, R is the rotation angle, t is the translation distance, k is the number of the nearest point pairs on the plane Qv, and x_iv and y_iv are the perpendicular foot coordinate values;

[0112] S97, translating and rotating the spliced ​​point cloud data set B according to the rotation angle R and the translation distance t to obtain a new corresponding point cloud set B';

[0113] S98. Make a plane Q through the points on the new corresponding point cloud set B' A The perpendicular line of the point is used to calculate the distance D from the point to the plane. i , according to the distance D i Calculate the average distance D between the new corresponding point cloud set B' and the target point set A 平均 ;

[0114]

[0115] Where D 平均 is the average distance, D i Q is the point to plane A The distance, N is the number of points;

[0116] S99, if D 平均 If the error is less than the set splicing error d', the iteration stops, otherwise it returns to S95 until the termination condition D is met. 平均 Less than the set splicing error d';

[0117] S910, updating the spliced ​​point cloud data to target point cloud data A, updating the reselected point cloud data to spliced ​​point cloud data B, and returning to S91 to splice the point cloud data of the H-beam 6, until all the image point cloud data are spliced, and obtaining all the point cloud data of the H-beam 6;

[0118] S911, perform denoising on all point cloud data of H-beam 6 after splicing. X -R≤X i ≤L X +L+R, -W / 2-T≤Y i The point cloud data within the range of ≤W / 2+T are retained, and those beyond the range are eliminated. After the elimination is completed, the complete H-beam 6 point cloud data is obtained;

[0119] Where R is the allowable reserved value in the length direction, and T is the allowable reserved value in the width direction. The reserved value size is set in the computer according to requirements.

[0120] S10, performing linear fitting on the complete point cloud data of the H-beam 6 obtained in S7 by using a weighted least squares linear fitting algorithm to obtain contour lines L1, L2, L3 and L4 of the H-beam 6;

[0121] S10 includes the following steps:

[0122] S101, set each point cloud data P of H-beam 6 i The weight coefficient ω i ;

[0123]

[0124] In the formula, ω i is the point cloud data weight system, x i It is the horizontal x-coordinate value of the point cloud data;

[0125] S102, construct the least square linear fitting function of the H-beam 6 contour line:

[0126]

[0127] In the formula, l i is the H-beam 6 contour function, a is the function slope, b is the intercept, n is the number of fitting points, x i ,y i are the coordinate values ​​of the fitting points.

[0128] S103, calculate the a and b values ​​of the weighted least squares linear fitting algorithm function of the H-beam 6 contour line

[0129]

[0130] S104 , repeat S102 and S103 to calculate and obtain the contour lines of the H-shaped steel 6 , which are marked as L1 , L2 , L3 and L4 respectively.

[0131] S11, according to the length and width of the H-beam 6, L1 and L3 are selected as the reference, and the center point of the contour line of the H-beam 6 is retrieved by the nearest neighbor search method within the radius R. After the center point is determined, the weighted least squares linear fitting algorithm is used again to obtain the center line L0 of the contour of the H-beam 6;

[0132] Specifically, the Octree search algorithm is used for retrieval. In other embodiments of the present invention, other algorithms may also be used for retrieval.

[0133] S12, calculate the coordinate value O1 (x) of the intersection value based on the center line L0 of the H-beam 6 contour and the contour lines L2 and L4 of the H-beam 6 o1 ,y o1 , H) and O2(x o2 ,y o2 , H), calculate the angle with the horizontal X-axis according to the coordinate value of the intersection point, which is the deflection angle, recorded as θ, and the offset E of the left end point from the horizontal axis. The calculation formula is as follows:

[0134]

[0135] Where E is the offset of the endpoint from the horizontal axis, θ is the deflection angle, and the angle between the intersection coordinate value and the horizontal X-axis is calculated;

[0136] S13, adjusting the H-beam 6 according to the offset E and the deflection angle θ, firstly translating the left end point on the center line of the H-beam 6 by an offset E, and then rotating the axis of the H-beam 6 by θ, so that the center line is always aligned with the center line of the machine tool worktable 1.

[0137] The present invention has the following advantages: by installing a CCD camera 4 on a processing machine tool, the CCD camera 4 obtains the deflection angle between the center line of the large H-shaped steel and the axis of the machine tool motion axis, and the offset between the center line of the large H-shaped steel 6 and the center line of the machine tool. By adjusting these two parameters, the center line of the large H-shaped steel 6 is made to coincide with the axis of the machine tool motion axis, and at the same time, the center line of the large H-shaped steel 6 is consistent with the center line of the machine tool, which can conveniently realize bilateral equal processing amount cutting, providing great convenience for processing programming, and at the same time, the tool wear in the bilateral milling process can be controlled to be basically consistent, thereby reducing the downtime time for tool changing.

[0138] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for positioning and adjusting H-beam machine tool processing, characterized in that: The following steps are involved: S1. Place the H-shaped steel on the machine tool workbench, install standard measuring points on the upper and lower sides of the machine tool workbench, marked as P1 and P2, and install standard measuring points on the front and back sides of the machine tool workbench, marked as P3 and P4; S2. A machine tool column is installed on the machine tool workbench, and a CCD camera is arranged on the machine tool column. The CCD camera can be rotated relative to the machine tool workbench to change the shooting angle of the CCD camera; S3. Establish a coordinate system XOY, with the installation point of the machine column as the origin O, the center line of the length direction of the machine table as the X axis, the width direction as the Y axis, and the center line of the machine column as the Z axis; S4, measuring the installation height H0 of the CCD camera, the length L of the H-shaped steel, the width W of the H-shaped steel and the height H of the H-shaped steel; S5, adjust the data acquisition range of the CCD camera, set point P1 as the starting point of up and down shooting, set point P2 as the end point of up and down shooting, set point P3 as the starting point of front and back shooting, and set point P4 as the end point of front and back shooting; S6. Set the angular velocity of the CCD camera to The angular velocity of one rotation back and forth is Set the shooting path of the CCD camera. The up-down shooting path is from the standard measuring point P1 to the standard measuring point P2, and the front-back shooting path is from the standard measuring point P3 to the standard measuring point P4. S7, when the CCD camera is aimed at the initial point P1 shooting position, the angular velocity Take pictures along the up and down shooting path. When the CCD camera is aimed at the initial point P3 shooting position, the angular velocity Take pictures along the front and back shooting paths, and store the data in a computer after the pictures are taken; S8, performing pixel point cloud preprocessing on the obtained image, selecting points on the outer edge of the H-beam on the image as image stitching points, and calculating the coordinate values ​​of the H-beam image merging points on the image based on the imaging principle of the CCD camera; S9. Using the ICP point cloud stitching algorithm in a computer to stitch the coordinate values ​​of the merged points, and then performing point cloud data denoising to form point cloud data of the H-beam; S10, performing linear fitting on the complete H-beam point cloud data obtained in S7 by using a weighted least squares linear fitting algorithm to obtain contour lines L1, L2, L3 and L4 of the H-beam; S11, according to the length and width of the H-beam, L1 and L3 are selected as the reference, and the center point of the contour line of the H-beam is retrieved by the nearest neighbor search method within the radius R. After the center point is determined, the weighted least squares linear fitting algorithm is used again to obtain the center line L0 of the H-beam contour; S12, calculate the coordinate value O1 (x) of the intersection value based on the center line L0 of the H-beam profile and the H-beam profile lines L2 and L4 o1 ,y o1 , H) and O2(x o2 ,y o2 , H), calculate the angle with the horizontal X-axis according to the coordinate value of the intersection point, which is the deflection angle, recorded as θ, and the offset E of the left end point from the horizontal axis. The calculation formula is as follows: Where E is the offset of the endpoint from the horizontal axis, θ is the deflection angle, and the angle between the intersection coordinate value and the horizontal X-axis is calculated; S13. Adjust the H-beam according to the offset E and the deflection angle θ. First, translate the left end point on the center line of the H-beam by an offset E, and then rotate the axis of the H-beam by θ so that the center line is always aligned with the center line of the machine tool worktable.

2. The H-beam machine tool processing positioning adjustment method according to claim 1 is characterized in that: In S2, a turntable is installed on the machine tool column, and the turntable is used to install the CCD camera. The turntable can be rotated relative to the machine tool worktable to change the shooting angle of the CCD camera.

3. The H-beam machine tool processing positioning adjustment method according to claim 1 is characterized in that: In S4, the measurement is performed using a laser measuring instrument.

4. The H-beam machine tool processing positioning adjustment method according to claim 1 is characterized in that: In S5, when the CCD camera can capture point P1, the angle between the shooting angle and the axis Z at this time is marked as α1, when the CCD camera can capture point P2, the angle between the shooting angle and the axis Z at this time is marked as α2, when the CCD camera can capture point P3, the angle between the shooting angle and the axis Z at this time is marked as β1, and when the CCD camera can capture point P4, the angle between the shooting angle and the axis Z at this time is marked as β2.

5. The H-beam machine tool processing positioning adjustment method according to claim 1, characterized in that: In S8, point P on the outer edge of the H-beam on the image i , P i+1 , P i+2 and P i+3 The image stitching point.

6. The H-beam machine tool processing positioning adjustment method according to claim 5 is characterized in that: S8 includes the following steps: S81. Determine the H-beam image stitching point P i , P i+1 , P i+2 and P i+3 location; S82. Calculate the upper and lower corners of each splicing point and front and rear corners In the formula, m is the number of times the high-precision turntable rotates up and down, and n is the number of times the high-precision turntable rotates forward and backward; S83, calculate the image splicing point P from the focus of the CCD camera to the H-beam according to the imaging principle of the CCD camera. i The distance L i , the formula is: L i =f i ·H / H0 i=1,2,3... Where, L i is the distance from the focus of the CCD camera to the image stitching point on the H-beam, f i is the focal length of the CCD camera at the i-th shooting, H is the height of the steel section, H0 is the installation height of the CCD camera, and i is the sequence number at the i-th shooting; S84, based on the distance L from the CCD camera focus to the image stitching point on the H-beam i And the upper and lower rotation angle α i and the front-to-back angle β i Calculate the coordinate value of the image merging point Pi, the calculation formula is: P i =(L i Sinai i cosβ i ,L i Sinai i sinβ i ,H) Where, P i is the coordinate of the merging point, L i is the distance from the CCD camera focus to the image stitching point on the H-beam, α i is the angle of the CCD camera turning up and down, β i is the forward and backward rotation angle of the CCD camera, and H is the height of the steel section.

7. The H-beam machine tool processing positioning adjustment method according to claim 1, characterized in that: S9 includes the following steps: S91. Set the critical angle ρ in the computer th , stitching error d', select the point cloud data of any two adjacent images as the point cloud data to be merged, A is the target point cloud data, and B is the stitching point cloud data; S92, randomly select three points P in the target point cloud data A i , P i+1 , P i+2 Construct a plane QA, and draw the normal η of the plane through any point pi ; S93. Pick any three points Q in the spliced ​​point cloud data B. i , Q i+1 , Q i+2 Construct a plane and draw the normal η of the plane through one point Qi ; S94, calculate normal η pi With normal η Qi If the angle ρ is greater than the set critical angle ρ th , then return to S93 and reselect any three points in the spliced ​​point cloud data B as the normal line η of the plane Qi , until the normal η pi With normal η Qi The angle ρ between them is less than or equal to the set critical angle ρ th , record the plane at this time as Q v ; S95, through plane Q v Different points on the plane Q A Draw perpendicular lines with distances d1, d2, ...d 1+v , determine the minimum distance, d iv =min(d1, d2…d 1+v ), and according to the minimum distance d iv Determine the coordinates d of the corresponding foot of the perpendicular iv (x iv ,y iv ); S96, according to different vertical foot coordinate values ​​d iv (x iv ,y iv ) to find the rotation angle R and translation distance t, the calculation formula is: Where f(R,t) is a function of the rotation angle R and the translation distance t, R is the rotation angle, t is the translation distance, k is the number of the nearest point pairs on the plane Qv, and x_iv and y_iv are the perpendicular foot coordinate values; S97, translating and rotating the spliced ​​point cloud data set B according to the rotation angle R and the translation distance t to obtain a new corresponding point cloud set B'; S98. Make a plane Q through the points on the new corresponding point cloud set B' A The perpendicular line of the point is used to calculate the distance D from the point to the plane. i , according to the distance D i Calculate the average distance D between the new corresponding point cloud set B' and the target point set A 平均 ; Where D 平均 is the average distance, D i Q is the point to plane A The distance, N is the number of points; S99, if D 平均 If the error is less than the set splicing error d', the iteration stops, otherwise it returns to S95 until the termination condition D is met. 平均 Less than the set splicing error d'; S910, updating the spliced ​​point cloud data to target point cloud data A, updating the reselected point cloud data to spliced ​​point cloud data B, and returning to S91 to splice the point cloud data of the H-beam until all the image point cloud data are spliced ​​to obtain all the point cloud data of the H-beam; S911, denoise all point cloud data of H-beam after splicing. X -R≤X i ≤L X +L+R, -W / 2-T≤Y i The point cloud data within the range of ≤W / 2+T are retained, and those beyond the range are eliminated. After the elimination is completed, the complete H-beam point cloud data is obtained; Where R is the allowable reserved value in the length direction, and T is the allowable reserved value in the width direction. The reserved value size is set in the computer according to requirements.

8. The H-beam machine tool processing positioning adjustment method according to claim 1, characterized in that: S10 includes the following steps: S101, set each point cloud data P of H-beam i The weight coefficient ω i ; In the formula, ω i is the point cloud data weight system, x i It is the horizontal x-coordinate value of the point cloud data; S102. Construct the least square linear fitting function of the H-beam contour line: In the formula, l i is the H-beam contour function, a is the function slope, b is the intercept, n is the number of fitting points, x i ,y i is the coordinate value of the fitting point; S103, calculate the a and b values ​​of the weighted least squares linear fitting algorithm function of the H-beam contour line S104. Repeat S102 and S103 to calculate the contour lines of the H-shaped steel, which are marked as L1, L2, L3 and L4 respectively.

9. The H-beam machine tool processing positioning adjustment method according to claim 1, characterized in that: In S11, the Octree search algorithm is used for retrieval.

10. The H-beam machine tool processing positioning adjustment method according to claim 9, characterized in that: The search radius of the Octree search algorithm is R=W / 2.

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