A multi-layer multi-pass welding path planning method for a tower support robot

Abstract

This invention discloses a multi-layer, multi-pass welding path planning method for a robot for tower support components, comprising the following steps: (1) establishing a workpiece coordinate system based on the structural characteristics of the workpiece; (2) measuring the geometric parameters of the workpiece and the reference position coordinates of the weld endpoint in the workpiece coordinate system; (3) determining the welding process parameters; (4) calculating the reference position coordinates of the weld endpoint in the workpiece coordinate system; (5) planning the welding gun posture based on the bevel angle and side plate inclination parameters; (6) planning multi-layer, multi-pass welding based on the welding process parameters; (7) planning the welding sequence based on the workpiece geometric parameters; (8) generating a complete multi-layer, multi-pass welding path. This invention requires no manual teaching throughout the process, and not only plans the welding position, but also the welding gun posture and multi-layer, multi-pass welding path. The parametric modeling method is flexible and adaptable to workpieces with various geometric configurations. The welding sequence is adaptively adjusted according to different workpieces to meet actual process requirements.

Description

Technical Field

[0001] This invention relates to the field of path planning, and more particularly to a method for planning multi-layer, multi-pass welding paths for a robot supporting iron tower components. Background Technology

[0002] Traditional iron tower support components are usually manufactured by manual welding, but the welding industry is currently facing problems such as difficulty in recruiting workers, low efficiency, and difficulty in quality control.

[0003] To address the aforementioned problems, Chinese Patent CN112658521A discloses a parametric, teach-free welding method for tower legs, a computer device, and a storage medium. This method includes: teaching a welding sample to obtain point data; establishing a tower leg reference coordinate system based on the point data obtained through teaching; acquiring tower leg parameters; offsetting the tower leg reference coordinate system to obtain a tower leg reference coordinate system; calculating the coordinates of each endpoint of the tower leg weld in the tower leg reference coordinate system; and determining the weld trajectory of the tower leg based on the coordinates of each endpoint and completing the welding. This invention allows for a single teaching session, eliminating the need for subsequent welding, thus effectively solving the problem of existing technologies requiring repeated programming due to the large variety and differences in tower leg workpieces. However, this method still requires one manual teaching session, lacks planning for the welding torch posture, cannot meet the needs of actual multi-layer and multi-pass welding, and the welding sequence is not adjusted according to process requirements. Furthermore, the parametric method lacks genericity.

[0004] Currently, there is no teaching-free, parameterized method for planning multi-layer, multi-pass welding paths for tower support robots that can meet the requirements of graded weld processes, both domestically and internationally. Summary of the Invention

[0005] Purpose of the invention: The purpose of this invention is to provide a multi-layer, multi-pass welding path planning method for a robot for tower support components. This method not only plans the welding position but also the welding torch posture and the multi-layer, multi-pass welding path, adapting to workpieces with various geometric configurations. The welding sequence is adaptively adjusted according to different workpieces.

[0006] Technical solution: The present invention provides a method for planning multi-layer, multi-pass welding paths for a robot used in tower support components, comprising the following steps:

[0007] (1) Establish the workpiece coordinate system based on the structural characteristics of the workpiece;

[0008] (2) Measure the geometric parameters of the workpiece and the reference position coordinates of the weld endpoint in the workpiece coordinate system;

[0009] (3) Determine the welding process parameters;

[0010] (4) Calculate the reference position coordinates of the weld endpoint in the workpiece coordinate system;

[0011] (5) Plan the welding torch posture based on the bevel angle and side plate inclination parameters;

[0012] (6) Plan multi-layer, multi-pass welding according to welding process parameters;

[0013] (7) Plan the welding sequence based on the workpiece's geometric parameters;

[0014] (8) Generate a complete multi-layer, multi-pass welding path.

[0015] Furthermore, the rules for establishing the workpiece coordinate system in step (1) are as follows: the iron tower support workpiece consists of a base plate and two side plates. One side plate is a whole plate, and the other side plate is divided into two sub-blocks distributed on both sides of the whole plate. The two side plates are intersected by a cross and are perpendicular in space, forming an angle with the base plate. The center of the base plate is taken as the origin O, the vertical direction perpendicular to the base plate is taken as the positive direction of the Z axis, and the straight line in the plane of the base plate parallel to the whole side plate is taken as the Y axis (positive direction is determined by the user). The X axis direction can be determined by the right-hand rule.

[0016] Furthermore, the geometric parameters of the workpiece in step (2) include: the length bX of the base plate in the X direction, the length bY of the base plate in the Y direction, the thickness bZ of the base plate, and the inclination angle of the X side plate. Y-side plate inclination angle X-side plate length H, side plate thickness C, X-axis center offset Y-axis offset towards the center , bevel depth d, bevel angle a.

[0017] Furthermore, the welding process parameters in step (3) include: weld leg height K and weld stacking amount l.

[0018] Furthermore, the calculation method for the reference position coordinates of the weld endpoint in step (4) is as follows: calculate the projection of the side plate thickness in the X+ and Y+ directions. and The projection of the bevel in the X+ and Y+ directions and The projection of the side panel height in the X+ / Y+ / Z+ directions / / The X, Y, and Z components of the weld endpoint coordinates are obtained by adding or subtracting the workpiece's geometric parameters from the aforementioned projection parameters. The calculation method for the reference position coordinates of the weld start and end points is as follows:

[0019] Coordinates of the weld start point in the X-axis direction: The coordinates of the weld start point in the Y-axis direction: Coordinates of the weld start point in the Z-axis direction: The sign depends on the location of the weld on the positive or negative half of the coordinate axis.

[0020] Coordinates of the weld endpoint in the X-axis direction: The coordinates of the weld endpoint in the Y-axis direction: The coordinates of the weld endpoint in the Z-axis direction: The sign depends on the location of the weld on the positive or negative half of the coordinate axis.

[0021] Furthermore, step (5) includes the following steps:

[0022] (51) Define the welding torch tool coordinate system, where the plane containing the welding torch is the ZX plane; the normal to the tip of the welding torch is the Z-axis direction, the front end of the welding torch is the X-axis direction, and the Y-axis direction can be determined by the right-hand rule; where the formula of the right-hand rule is: ;

[0023] (52) Define the rotation matrix corresponding to the welding torch posture as follows: The calculation method is as follows:

[0024] Determine the basic orientation matrix based on the orientation of the weld. The welding torch tilt posture transformation matrix is ​​determined based on the bevel angle and side plate inclination angle. The welding torch tilt attitude transformation matrix is ​​determined according to the welding process requirements. The final position of the welding torch ;in:

[0025] ;

[0026] For weld seams 1X / 2X / 3X / 4X , , ;

[0027] For weld seams 1Y / 2Y / 3Y / 4Y, , , ;

[0028] For weld seams 1Z / 2Z / 3Z / 4Z , , ;

[0029] above Take a negative sign when the weld is located on the positive half axis and a positive sign when it is located on the negative half axis;

[0030] Define the rotation angle of the X-axis of the welding torch tool coordinate system. For bevel welds 1X / 3X / 2Y / 4Y / 2Z / 4Z, For the remaining bevel welds, For fillet welds 1X / 2X, (2X is negative); for fillet welds, 3X / 4X, (4X is negative); for fillet welds 1Y / 4Y, Where 1Y is negative; for fillet welds 2Y / 3Y, Where 3Y is negative; for fillet welds 1Z / 2Z / 3Z / 4Z, Where 1Z / 3Z is negative; then the transformation matrix of the tilt attitude. for:

[0031]

[0032] Define the welding torch feed angle as Then the transformation matrix of the tilt attitude for:

[0033] .

[0034] Furthermore, step (6) includes the following steps:

[0035] (61) Calculate the theoretical throat size of the fillet weld based on the weld leg height in the welding process parameters, including: the throat size of the bevel weld and the throat size of the fillet weld;

[0036] (62) For a single weld, the amount of weld stacking in the welding process parameters shall be determined accordingly. and throat size The calculation method for the number of welding layers for bevel welds and fillet welds is as follows: ), ceil means rounding up.

[0037] Furthermore, step (61) includes the following steps:

[0038] (611) Based on the bevel depth and bevel angle Calculate the throat dimensions of the bevel weld:

[0039] X / Y axis welds: ;

[0040] Z-axis weld: ;

[0041] (612) Based on the height of the weld leg and side plate angle / Calculate the throat dimensions of the fillet weld :

[0042] X-axis weld: (1 / 2 quadrant); (3 / 4 quadrant);

[0043] Y-axis weld: (1 / 2 quadrant); (3 / 4 quadrant);

[0044] Z-axis weld: .

[0045] Further, step (7) specifically involves: first performing root welding on each weld seam in a specific order, and then performing fill welding in any order; the root welding order is as follows: first determine the largest quadrant, that is, the quadrant in which the two included angles between the two side plates and the bottom plate are both acute angles; if the largest quadrant is 2 / 4 quadrant, start clockwise welding from the counterclockwise adjacent quadrant of the largest quadrant; if the largest quadrant is 1 / 3 quadrant, start counterclockwise welding from the clockwise adjacent quadrant of the largest quadrant; the specific welding order is determined according to the workpiece coordinate system.

[0046] Furthermore, step (8) specifically involves the following calculation method for the coordinates of the endpoints of each weld layer:

[0047] Define the coordinates of the weld endpoints during the root pass as follows: If the rotation matrix corresponding to the welding torch posture is R, then the pose matrix of the welding torch at that point is... for:

[0048] ;

[0049] If the number of welding layers of the bevel weld is The number of welding layers for fillet welds is Then the welding torch is used to weld the nth layer. At that time, the pose matrix of the welding torch at the weld end point for:

[0050]

[0051] in The transformation matrix for the tool coordinate system is calculated as follows:

[0052] .

[0053] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: no manual teaching is required throughout the process; not only is the welding position planned, but also the welding torch posture and multi-layer multi-pass welding path are planned; the parametric modeling method is flexible and adaptable to workpieces with various geometric configurations; the welding sequence is adaptively adjusted according to different workpieces to meet actual process requirements. Attached Figure Description

[0054] Figure 1 This is the front view of the present invention;

[0055] Figure 2 This is the left view of the present invention;

[0056] Figure 3 This is a top view of the present invention;

[0057] Figure 4 This is a partial enlarged view of the weld seam of the present invention. Detailed Implementation

[0058] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0059] like Figure 1 As shown in the embodiment of the present invention, a multi-layer, multi-pass welding path planning method for a tower support robot includes the following steps:

[0060] (1) Establish a workpiece coordinate system based on the structural characteristics of the workpiece; the rules for establishing the workpiece coordinate system are as follows: the iron tower support workpiece consists of a base plate and two side plates, one of which is a whole plate, and the other side plate is divided into two sub-blocks distributed on both sides of the whole plate. The two side plates are intersected by a cross and are perpendicular in space, forming an angle with the base plate; the center of the base plate is taken as the origin O, the vertical direction perpendicular to the base plate is taken as the positive direction of the Z axis, the straight line in the plane of the base plate parallel to the whole side plate is taken as the Y axis (positive direction is determined by the user), and the X axis direction is determined by the right-hand rule.

[0061] (2) Measure the geometric parameters of the workpiece and the reference position coordinates of the weld endpoint in the workpiece coordinate system; the geometric parameters of the workpiece include: the length bX of the base plate in the X direction, the length bY of the base plate in the Y direction, the thickness bZ of the base plate, and the inclination angle of the X side plate. Y-side plate inclination angle X-side plate length H, side plate thickness C, X-axis center offset Y-axis offset towards the center , bevel depth d, bevel angle a.

[0062] (3) Determine the welding process parameters; the welding process parameters include: weld leg height K and weld stacking amount l.

[0063] (4) Calculate the reference position coordinates of the weld endpoint in the workpiece coordinate system; the calculation method for the reference position coordinates of the weld endpoint is as follows: calculate the projection of the side plate thickness in the X+ and Y+ directions. and Projections of the bevel in the X+ and Y+ directions and The projection of the side panel height in the X+ / Y+ / Z+ directions / / The X, Y, and Z components of the weld endpoint coordinates are obtained by adding or subtracting the workpiece's geometric parameters from the aforementioned projection parameters. The calculation method for the reference position coordinates of the weld start and end points is as follows:

[0064] Coordinates of the weld start point in the X-axis direction: The coordinates of the weld start point in the Y-axis direction: Coordinates of the weld start point in the Z-axis direction: The sign depends on the location of the weld on the positive or negative half of the coordinate axis.

[0065] Coordinates of the weld endpoint in the X-axis direction: The coordinates of the weld endpoint in the Y-axis direction: The coordinates of the weld endpoint in the Z-axis direction: The sign depends on the location of the weld on the positive or negative half of the coordinate axis.

[0066] (5) Based on the bevel angle and side plate inclination parameters, plan the welding torch posture; including the following steps:

[0067] (51) Define the welding torch tool coordinate system, where the plane containing the welding torch is the ZX plane; the normal to the tip of the welding torch is the Z-axis direction, the front end of the welding torch is the X-axis direction, and the Y-axis direction can be determined by the right-hand rule; where the formula of the right-hand rule is: ;

[0068] (52) Define the rotation matrix corresponding to the welding torch posture as follows: The calculation method is as follows:

[0069] Determine the basic orientation matrix based on the orientation of the weld. The welding torch tilt posture transformation matrix is ​​determined based on the bevel angle and side plate inclination angle. The welding torch tilt attitude transformation matrix is ​​determined according to the welding process requirements. The final position of the welding torch ;in:

[0070] ;

[0071] For weld seams 1X / 2X / 3X / 4X , , ;

[0072] For weld seams 1Y / 2Y / 3Y / 4Y, , , ;

[0073] For weld seams 1Z / 2Z / 3Z / 4Z , , ;

[0074] above Take a negative sign when the weld is located on the positive half axis and a positive sign when it is located on the negative half axis;

[0075] Define the rotation angle of the X-axis of the welding torch tool coordinate system. For bevel welds 1X / 3X / 2Y / 4Y / 2Z / 4Z, For the remaining bevel welds, For fillet welds 1X / 2X, (2X is negative); for fillet welds, 3X / 4X, (4X is negative); for fillet welds 1Y / 4Y, Where 1Y is negative; for fillet welds 2Y / 3Y, Where 3Y is negative; for fillet welds 1Z / 2Z / 3Z / 4Z, Where 1Z / 3Z is negative; then the transformation matrix of the tilt attitude. for:

[0076]

[0077] Define the welding torch feed angle as Then the transformation matrix of the tilt attitude for:

[0078] .

[0079] (6) Plan multi-layer, multi-pass welding according to welding process parameters; including the following steps:

[0080] (61) Calculate the theoretical throat size of the fillet weld based on the weld leg height in the welding process parameters, including: the throat size of the bevel weld and the throat size of the fillet weld; including the following steps:

[0081] (611) Based on the bevel depth and bevel angle Calculate the throat dimensions of the bevel weld:

[0082] X / Y axis welds: ;

[0083] Z-axis weld: ;

[0084] (612) Based on the height of the weld leg and side plate angle / Calculate the throat dimensions of the fillet weld :

[0085] X-axis weld: (1 / 2 quadrant); (3 / 4 quadrant);

[0086] Y-axis weld: (1 / 2 quadrant); (3 / 4 quadrant);

[0087] Z-axis weld: .

[0088] (62) For a single weld, the amount of weld stacking in the welding process parameters shall be determined accordingly. and throat size The calculation method for the number of welding layers for bevel welds and fillet welds is as follows: ), ceil means rounding up.

[0089] (7) Plan the welding sequence according to the workpiece geometric parameters; specifically: first, perform root welding on each weld in a specific order, and then perform fill welding in any order; the root welding sequence is as follows: first determine the largest quadrant, that is, the quadrant in which the two side plates and the bottom plate have two acute angles; if the largest quadrant is 2 / 4 quadrant, start clockwise welding from the counterclockwise adjacent quadrant of the largest quadrant; if the largest quadrant is 1 / 3 quadrant, start counterclockwise welding from the clockwise adjacent quadrant of the largest quadrant; the specific welding sequence is determined according to the workpiece coordinate system.

[0090] (8) Generate a complete multi-layer, multi-pass welding path; specifically, the coordinate calculation method for the endpoints of each layer of weld is as follows:

[0091] Define the coordinates of the weld endpoints during the root pass as follows: If the rotation matrix corresponding to the welding torch posture is R, then the pose matrix of the welding torch at that point is... for:

[0092] ;

[0093] If the number of welding layers of the bevel weld is The number of welding layers for fillet welds is Then the welding torch is used to weld the nth layer. At that time, the pose matrix of the welding torch at the weld end point for:

[0094]

[0095] in The transformation matrix for the tool coordinate system is calculated as follows: .

Claims

1. A method for planning multi-layer, multi-pass welding paths for a robot in tower support components, characterized in that, Includes the following steps: (1) Establish the workpiece coordinate system based on the structural characteristics of the workpiece; (2) Measure the geometric parameters of the workpiece and the reference position coordinates of the weld endpoint in the workpiece coordinate system; the geometric parameters of the workpiece include: the length bX of the base plate in the X direction, the length bY of the base plate in the Y direction, the thickness bZ of the base plate, and the inclination angle of the X side plate. Y-side plate inclination angle X-side plate length H, side plate thickness C, X-axis center offset Y-axis offset towards the center , bevel depth d, bevel angle a; (3) Determine the welding process parameters; the welding process parameters include: weld leg height K, weld stacking amount l; (4) Calculate the reference position coordinates of the weld endpoint in the workpiece coordinate system; the calculation method for the reference position coordinates of the weld endpoint is as follows: calculate the projection of the side plate thickness in the X+ and Y+ directions. and Projections of the bevel in the X+ and Y+ directions and The projection of the side panel height in the X+ / Y+ / Z+ directions / / The X, Y, and Z components of the weld endpoint coordinates are obtained by adding or subtracting the workpiece's geometric parameters from the above projection parameters; the calculation method for the reference position coordinates of the weld start and end points is as follows: Coordinates of the weld start point in the X-axis direction: The coordinates of the weld start point in the Y-axis direction: Coordinates of the weld start point in the Z-axis direction: The sign depends on the location of the weld on the positive or negative half of the coordinate axis; the coordinates of the weld endpoint in the X-axis direction are: The coordinates of the weld endpoint in the Y-axis direction: The coordinates of the weld endpoint in the Z-axis direction: The sign depends on the location of the weld on the positive or negative half of the coordinate axis. (5) Based on the bevel angle and side plate tilt angle parameters, plan the welding torch posture; including the following steps: (51) Define the welding torch tool coordinate system, where the plane containing the welding torch is the ZX plane; the normal to the welding torch tip is the Z-axis direction, the welding torch front end is the X-axis direction, and the Y-axis direction is determined by the right-hand rule; where the right-hand rule formula is: ; (52) Define the rotation matrix corresponding to the welding torch posture as follows: The calculation method is as follows: Determine the basic orientation matrix based on the orientation of the weld. The welding torch tilt posture transformation matrix is ​​determined based on the bevel angle and side plate inclination angle. The welding torch tilt attitude transformation matrix is ​​determined according to the welding process requirements. The final position of the welding torch ;in: ； For weld seams 1X / 2X / 3X / 4X , , ; For weld seams 1Y / 2Y / 3Y / 4Y, , , ; For weld seams 1Z / 2Z / 3Z / 4Z , , ; above Take a negative sign when the weld is located on the positive half axis and a positive sign when it is located on the negative half axis; Define the rotation angle of the X-axis of the welding torch tool coordinate system. For bevel welds 1X / 3X / 2Y / 4Y / 2Z / 4Z, For the remaining bevel welds, For fillet welds 1X / 2X, 2X is negative; for fillet welds, 3X / 4X, 4X is negative; for fillet welds 1Y / 4Y, Where 1Y is negative; for fillet welds 2Y / 3Y, Where 3Y is negative; for fillet welds 1Z / 2Z / 3Z / 4Z, Where 1Z / 3Z is negative; then the transformation matrix of the tilt attitude. for: Define the welding torch feed angle as Then the transformation matrix of the tilt attitude for: ； (6) Plan multi-layer, multi-pass welding according to welding process parameters; including the following steps: (61) Calculate the theoretical throat size of the fillet weld based on the weld leg height in the welding process parameters, including: the throat size of the bevel weld and the throat size of the fillet weld; (62) For a single weld, the amount of weld stacking in the welding process parameters shall be determined accordingly. and throat size The calculation method for the number of welding layers for bevel welds and fillet welds is as follows: ), ceil means round up; (7) Plan the welding sequence based on the workpiece's geometric parameters; (8) Generate a complete multi-layer, multi-pass welding path.

2. The method for planning multi-layer, multi-pass welding paths for a robot in tower support components according to claim 1, characterized in that, The rules for establishing the workpiece coordinate system in step (1) are as follows: The tower support workpiece consists of a base plate and two side plates. One side plate is a single, solid plate, and the other side plate is divided into two sub-blocks distributed on both sides of the solid plate. The two side plates intersect at a cross and are spatially perpendicular, forming an angle with the base plate. The origin O is the center of the base plate, the positive Z-axis is the vertically upward direction perpendicular to the base plate, the Y-axis is the straight line parallel to the solid side plate in the plane of the base plate, and the X-axis direction is determined by the right-hand rule. The formula for the right-hand rule is: .

3. The method for planning multi-layer, multi-pass welding paths for a robot in tower support components according to claim 1, characterized in that, Step (61) includes the following steps: (611) Based on the bevel depth and bevel angle Calculate the throat dimensions of the bevel weld: X / Y axis welds: ; Z-axis weld: ; (612) Based on the height of the weld leg and side plate angle / Calculate the throat dimensions of the fillet weld : X-axis weld: ; 1 / 2 quadrant; ; 3 / 4 quadrant; Y-axis weld: ; 1 / 2 quadrant; ; 3 / 4 quadrant; Z-axis weld: .

4. The method for planning multi-layer, multi-pass welding paths for a robot in tower support components according to claim 1, characterized in that, The specific steps (7) are as follows: first, perform root welding on each weld in a specific order, and then perform fill welding in any order; the root welding order is as follows: first determine the largest quadrant, that is, the quadrant in which the two included angles between the two side plates and the bottom plate are both acute angles; if the largest quadrant is 2 / 4 quadrant, start welding clockwise from the counterclockwise adjacent quadrant of the largest quadrant. If the largest quadrant is 1 / 3 of the quadrant, start welding counterclockwise from the adjacent quadrant clockwise from the largest quadrant; the specific welding sequence is determined according to the workpiece coordinate system.

5. The method for planning multi-layer, multi-pass welding paths for a robot supporting iron tower components according to claim 1, characterized in that, The specific steps (8) are as follows: The coordinates of the endpoints of each weld layer are calculated as follows: Define the coordinates of the weld endpoints during the root pass as follows: If the rotation matrix corresponding to the welding torch posture is R, then the pose matrix of the welding torch at that point is... for: ； If the number of welding layers of the bevel weld is The number of welding layers for fillet welds is Then the welding torch is used to weld the nth layer. At that time, the pose matrix of the welding torch at the weld end point for: in The transformation matrix for the tool coordinate system is calculated as follows: 。

Images