Multi-layer multi-path planning method for space circumferential weld

Abstract

The invention discloses a multi-layer multi-path planning method for a space annular welding seam. The method comprises the steps that welding seam feature points are obtained; acquiring characteristic data of a weld joint section; determining a welding seam space position of each welding seam segment through the welding seam feature points to obtain welding seam segment data of the annular welding seam; the arc degree of each welding seam segment is obtained, and based on a preset welding starting point and a welding gun initial posture, the position of a breakpoint section at the welding seam segment and the welding gun posture at the corresponding breakpoint section are obtained; weld bead feature data of all layers of welding beads are obtained according to the feature data; welding beads of the corresponding layers in all the welding seam sections serve as the same-level welding bead layer in the circumferential welding seam, so that multiple layers and multiple paths of the circumferential welding seam are obtained; and multi-layer and multi-path planning of the space circumferential weld is achieved through the preset non-welding path and the multi-layer and multi-path. The problems that an existing space circumferential weld welding method is low in welding efficiency and insufficient in precision are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of welding, in particular to a multi-layer multi-pass path planning method for a space annular weld. BACKGROUND

[0002] In shipbuilding, there are significant difficulties in pipe system welding. After pipe system assembly, the shape is complex, the pipe diameter is from 10mm to 600mm, and the shape is complex, such as spiral, Z-shaped, U-shaped, etc. The design of welding bevel of different pipe diameters, the filling amount, and the welding requirements of multi-layer and multi-pass are quite different.

[0003] Generally, such pipe system welding adopts full position welding equipment or manual welding: however, manual welding has flexibility, but has low efficiency, and the parameter adjustment relies on the experience of on-site engineers, is affected by the difference in welding technology, and the welding quality is inconsistent. The full position welding equipment can cover flat, vertical, horizontal, and overhead full position welds, but the molten pool shape of different positions is greatly different due to gravity, and the welding parameters need to be adjusted on site to ensure the formation of the weld, and it is not universal. SUMMARY

[0004] The present application provides a multi-layer multi-pass path planning method for a space annular weld to overcome the above technical problems.

[0005] In order to achieve the above purpose, the technical scheme of the present application is: A multi-layer multi-pass path planning method for a space annular weld, specifically comprising the following steps: S1: obtaining the weld feature points of the weld section of the V-shaped butt weld through the preset laser system; and the weld feature points are the contour feature points of the weld section of the V-shaped butt weld; S2: obtaining the feature data of the weld section according to the weld feature points; and the feature data includes the bottom width, top width and section height of the weld section; S3: randomly dividing the annular weld into several weld segments; and confirming the weld space position of each weld segment through the weld feature points, and obtaining the segment data of the annular weld according to the weld space position; and the segment data at least includes the center point coordinates and the circular arc plane normal vector; S4: obtaining the circular arc degree of each weld segment, i.e. the radian value of the segment circular arc, and based on the preset welding starting point and the initial attitude of the welding torch, obtaining the position of the breakpoint section and the welding torch attitude at the corresponding breakpoint section; S5: randomly dividing each weld segment into several layers of welding passes with the same number of layers and different or same thickness, and obtaining the pass feature data of each layer of welding passes according to the feature data; and the pass feature data at least includes the pass starting point, the pass ending point and the pass thickness; S6: taking the welding beads of the corresponding layers in each welding segment as the same level bead layers in the annular welding seam to obtain the multi-layer and multi-pass path of the annular welding seam; S7: presetting a non-welding transition path for switching between different level beads; and realizing the multi-layer and multi-pass path planning of the spatial annular welding seam through the combination of the non-welding transition path and the multi-layer and multi-pass path.

[0006] Further, the S3 specifically comprises the following steps: S31: randomly dividing the annular welding seam into n welding segments; wherein the annular welding seam comprises n+1 breakpoint sections of initial section and terminal section; confirming the welding space position of each welding segment through the welding feature points, and setting the welding space position points A, B, C on the circular arc of the annular welding seam in each welding segment; S32: obtaining the welding segment data of the annular welding seam according to the welding space position points; and the welding segment data at least comprises the center point coordinate O and the circular arc plane normal vector e; The solving equation group of the center point coordinate is: , , , In the formula, U represents the middle point of the line connecting the welding space position point A and the welding space position point B; V represents the middle point of the line connecting the welding space position point B and the welding space position point C; , , , , , , All represent direction vectors; ˙ represents the vector dot product operator symbol; × represents the vector cross product operator symbol; The expression of the circular arc plane normal vector e is .

[0007] Further, the S4 specifically comprises the following steps: S41: obtaining the circular arc degree θ of each welding segment, and obtaining the rotation matrix Q according to the circular arc plane normal vector e, and the obtaining formula of the rotation matrix Q is , , In the formula, I represents a 3x3 unit matrix; E represents the skew-symmetric matrix of the circular arc plane normal vector e; e1, e2, e3 represent the spatial vector components of the circular arc plane normal vector e; S42: Based on the preset welding start point and welding torch initial posture, obtain the location of the break point section at the weld segment and the welding torch posture at the corresponding break point section according to the rotation matrix Q. The formula for determining the location of the fracture section at the weld segment is as follows: , In the formula: This indicates the location of the section where the weld segment breaks; Indicates the preset welding start point; The formula for obtaining the welding torch posture at the corresponding breakpoint section is as follows: , In the formula: This indicates the welding torch posture at the corresponding breakpoint section. This indicates the initial position of the welding torch.

[0008] Furthermore, S5 specifically includes the following steps: S51: Define each weld segment as comprising several layers of multiple weld passes. Define weld segment k as the intermediate segment between the breakpoint section k and the breakpoint section k+1. The weld segment k... The start and end points of a layered weld bead are defined as follows: ; S52: Based on the cross-sectional height of the weld section, confirm the first... The height at which the welding torch is raised during layer welding; And the The expression for the welding torch lift height of a layer weld bead is: , In the formula: Indicates the first The height at which the welding torch is raised during layer welding; Indicates the first [section height] defined by the [section height]. The thickness of the weld bead in the layer welding; S53: Obtain the coordinates of the center point O to the location of the section at the breakpoint k. Direction vector And the direction vector The formula for obtaining it is , And according to the direction vector Obtain the extended vector OB, and the formula for obtaining the extended vector OB is: , S54: Based on the center point coordinates O and the extended vector OB, obtain the first... The start point of a layered weld bead is expressed as: According to the center point coordinates O and the first layer welding bead welding torch lifting height, the first layer welding bead welding end point is obtained, and its expression is

[0009] Further, Z-shaped swing welding is also included for each layer welding bead in the multi-layer multi-pass path of the annular weld; And the swing amplitude of the Z-shaped swing welding by the welding torch is the welding bead width, and the calculation formula of the welding bead width is In the formula: The welding bead width of the first layer welding bead is represented; The top width is represented; The bottom angle of the isosceles trapezoid formed by the bottom width, the top width and the cross-sectional height is represented.

[0010] Beneficial effects: the present application provides a multi-layer multi-pass path planning method for a spatial annular weld, in the full position welding process of the spatial annular weld, the spatial annular weld is divided into different welding segments of multi-layer welding beads, and the corresponding layer welding bead in each weld segment is regarded as the same level bead layer in the annular weld to obtain the multi-layer multi-pass path of the entire spatial annular weld; at the same time, the bead characteristic data of each layer welding bead is calculated for different welding segments; and the bead characteristic data at least includes the bead starting point, the bead end point and the bead thickness, without adjusting the welding parameters on site to ensure the weld forming, which greatly improves the welding precision and efficiency of the spatial annular weld. BRIEF DESCRIPTION OF DRAWINGS

[0011] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0012] Figure 1 The flow chart of the present application, a multi-layer multi-pass path planning method for a spatial annular weld, is shown in the figure; Figure 2 The schematic diagram of the V-shaped butt weld weld cross section in the present embodiment is shown in the figure; Figure 3 The schematic diagram of the multi-layer multi-pass path of the spatial annular weld in the present embodiment is shown in the figure. DETAILED DESCRIPTION ​​​

[0013] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0014] The embodiment provides a multi-layer multi-pass path planning method for a space ring weld, and specifically comprises the following steps: S1: acquiring a weld feature point of a weld section of a V-shaped butt weld through a preset laser system; and the weld feature point is a contour feature point of the weld section of the V-shaped butt weld; Specifically, the preset laser system in the embodiment comprises a laser sensor and a laser controller, and the laser system is installed on a robot body configured with a robot control system. The robot control system is in communication connection with a welding system through a Mod bus TCP bus. The welding system is a known technology in the art, and comprises a welding power source, a cooling water tank, a wire feeder and a welding torch. The laser system, the robot control system, the robot control system and a preset host computer, and the laser system and the preset host computer are all in communication connection through a TCP network. The collaborative robot in the embodiment is used for executing a welding motion track and controlling the welding system. The laser system is used for weld identification. The method for weld identification of the laser system in the embodiment is a known technology in the art, and will not be described in detail herein. The welding system is used for executing a welding process. The host computer control system is used for human-computer interaction and multi-layer multi-pass welding program generation. The method for realizing human-computer interaction and multi-layer multi-pass welding program generation through the preset host computer control system in the embodiment is a known technology in the art, and will not be described in detail herein. S2: acquiring feature data of the weld section according to the weld feature point; and the feature data comprises a bottom width, a top width and a section height of the weld section; wherein the shape of the weld section in the embodiment is specifically an isosceles trapezoid; S3: randomly dividing the ring weld into a plurality of weld segments; and confirming the weld space position of each weld segment through the weld feature point, and acquiring segment data of the ring weld according to the weld space position; and the segment data at least comprises a center point coordinate and an arc plane normal vector; specifically comprising the following steps: S31: randomly dividing the ring weld into n weld segments; wherein the ring weld comprises n+1 breakpoint sections including an initial section and a terminal section; The welding seam space positions of each welding seam segment are determined by the welding seam feature points, and the welding seam space position points on the circular arc of the annular welding seam in each welding seam segment are set as A, B and C; S32: welding seam segment data of the annular welding seam is obtained according to the welding seam space position points; and the welding seam segment data at least includes a center point coordinate O and an arc plane normal vector e; The solving equation group of the center point coordinate is: , , , In the formula, U represents a middle point of a line connecting the welding seam space position point A and the welding seam space position point B; V represents a middle point of a line connecting the welding seam space position point B and the welding seam space position point C; , , , , , , all represent direction vectors; · represents a vector dot product operator symbol; and × represents a vector cross product operator symbol; The expression of the arc plane normal vector e is ; S4: the arc degree of each welding seam segment, that is, the radian value of the segment arc, is obtained, and based on a preset welding starting point and a welding gun initial attitude, the position of a breakpoint section at the welding seam segment and the welding gun attitude at the corresponding breakpoint section are obtained; specifically, the following steps are included: S41: the arc degree θ of each welding seam segment is obtained, and a rotation matrix Q is obtained according to the arc plane normal vector e, and the obtaining formula of the rotation matrix Q is , , In the formula, I represents a 3*3 unit matrix; E represents a skew-symmetric matrix of the arc plane normal vector e; e1, e2 and e3 represent the space vector components of the arc plane normal vector e; S42: based on the preset welding starting point and the welding gun initial attitude, the position of the breakpoint section at the welding seam segment and the welding gun attitude at the corresponding breakpoint section are obtained according to the rotation matrix Q; The obtaining formula of the position of the breakpoint section at the welding seam segment is , In the formula, represents the position of the breakpoint section at the welding seam segment; represents the preset welding starting point; The formula for obtaining the welding torch posture at the corresponding breakpoint section is as follows: , In the formula: This indicates the welding torch posture at the corresponding breakpoint section. Indicates the initial position of the welding torch; S5: Randomly divide each weld segment into several layers of weld beads with the same number of layers and different or the same thickness, and obtain the weld bead characteristic data of each layer of weld beads based on the characteristic data. Furthermore, the weld bead characteristic data includes at least the weld bead start point, weld bead end point, and weld bead thickness; Specifically, the following steps are included: S51: Define each weld segment as comprising several layers of multiple weld passes. Define weld segment k as the intermediate segment between the breakpoint section k and the breakpoint section k+1. The weld segment k... The start and end points of a layered weld bead are defined as follows: ; S52: Based on the cross-sectional height of the weld section, confirm the first... The height at which the welding torch is raised during layer welding; And the The expression for the welding torch lift height of a layer weld bead is: , In the formula: Indicates the first The height at which the welding torch is raised during layer welding; Indicates the first [section height] defined by the [section height]. The thickness of the weld bead in the layer welding; S53: Obtain the coordinates of the center point O to the location of the section at the breakpoint k. Direction vector And the direction vector The formula for obtaining it is , And according to the direction vector Obtain the extended vector OB, and the formula for obtaining the extended vector OB is: , S54: Based on the center point coordinates O and the extended vector OB, obtain the first... The start point of a layered weld bead is expressed as: , Based on the coordinates of the center point O and the first The welding torch height for each layer of welding is adjusted to obtain the first layer. The end point of a layered weld bead is expressed as:

[0015] S6: Take the corresponding layer of each weld segment as the same level of weld pass layer in the annular weld to obtain the multi-layer and multi-pass path of the annular weld; in this embodiment, in order to segment the weld path and plan the multi-layer and multi-pass welding path, the multi-layer weld pass distribution of each weld segment is obtained by considering that the weld is a spatial annular weld, according to the position of the breakpoint section of the weld segmentation and the welding gun posture, and finally the welding trajectory path of the entire spatial annular weld is obtained. In this embodiment, Z-type weaving welding is also used for each layer of weld pass in the multi-layer and multi-pass path of the annular weld; and the weaving amplitude of the Z-type weaving welding by the welding gun is the weld pass width, and the calculation formula of the weld pass width is , In the formula: represents the weld pass width of the first layer of weld pass; represents the top width; represents the bottom angle of the isosceles trapezoid formed by the bottom width, the top width and the section height, and is specifically as shown in Figure 2 , that is, a is the upper base of the trapezoid, which is composed of the feature point 1 and the feature point 2, the length of a can be obtained; b is the lower base of the trapezoid, which is composed of the feature point 4 and the feature point 6, the length of b can be obtained; is the bottom angle of the trapezoid, which is composed of the feature point 2, the feature point 1 and the feature point 4, the value of can be obtained according to the values of a, b and H based on the calculation formula of the known isosceles trapezoid; H is the height of the trapezoid, which can be obtained from the feature point 3 and the feature point 6; wherein in this embodiment, according to the weld pass width and the weld pass thickness, the selection of the Z-type weaving welding process parameters is the existing known technology content, which will not be described in detail here; S7: preset a non-welding transition path for switching between different levels of weld pass; and realize the multi-layer and multi-pass path planning of the spatial annular weld through the combination of the non-welding transition path and the multi-layer and multi-pass path. In this embodiment, all layer weld passes can use the same transition point or multiple transition points, and the transition path is set according to the welding scene setting. The purpose of setting the transition path is to avoid the accumulation of heat due to the on-site replacement of the weld pass, which causes the welding deformation of the weld pass. For the multi-layer and multi-pass welding of the spatial annular weld, in this embodiment, different welding process parameters can be preset according to the welding position, such as the position of the weld, such as flat welding, vertical welding, horizontal welding and overhead welding, to execute the welding operation.

[0016] The method has the beneficial effects that: by dividing the space annular weld into different welding segments of multi-layer welding beads in the process of the full position welding of the space annular weld, and taking the welding beads of the corresponding layer in each welding segment as the same level bead layer in the annular weld, the multi-layer multi-bead path of the whole space annular weld is obtained; meanwhile, the bead characteristic data of each layer welding bead is calculated for different welding segments; the bead characteristic data at least includes the bead starting point, the bead ending point and the bead thickness, and the Z-type weaving welding is adopted based on the welding width to realize the welding of the space annular weld, without adjusting the welding parameters on site to ensure the weld forming, so that the welding precision and efficiency of the space annular weld are greatly improved.

[0017] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A multi-layer multi-pass path planning method for a space ring weld, characterized by, Specifically comprising the following steps: S1: Obtain the weld feature points of the weld section of the V-shaped butt weld by a preset laser system; and the weld feature points are the profile feature points of the V-shaped butt weld weld section; S2: Obtain the feature data of the weld section according to the weld feature points; and the feature data includes the bottom width, top width and section height of the weld section; S3: Randomly divide the annular weld into a plurality of weld segments; and confirm the weld space position of each weld segment through the weld feature points, and obtain the segment data of the annular weld according to the weld space position; and the segment data at least includes the center point coordinates and the circular arc plane normal vector; S4: Obtain the circular arc degree of each weld segment, that is, the radian value of the segment circular arc, and obtain the position of the breakpoint section at the weld segment and the welding gun attitude at the corresponding breakpoint section based on the preset welding starting point and the initial attitude of the welding gun; S5: Divide each weld segment into a plurality of layer welding beads with the same number of layers and different or same thicknesses, and obtain the bead feature data of each layer welding bead according to the feature data; and the bead feature data at least includes the bead starting point, the bead ending point and the bead thickness; S6: Take the corresponding layer welding bead in each weld segment as the same level bead layer in the annular weld to obtain the multi-layer multi-pass path of the annular weld; S7: preset a non-welding transition path for switching between different level beads; and realize the multi-layer multi-pass path planning of the spatial annular weld through the combination of the non-welding transition path and the multi-layer multi-pass path.

2. A multi-layer multi-pass path planning method for a space ring weld according to claim 1, wherein, The S3 specifically comprises the following steps: S31: Randomly divide the annular weld into n weld segments; wherein the annular weld includes n+1 breakpoint sections including the initial section and the terminal section; confirm the weld space position of each weld segment through the weld feature points, and set the weld space position points A, B, C on the annular weld circular arc in each weld segment; S32: Obtain the weld segment data of the annular weld according to the weld space position points; and the weld segment data at least includes the center point coordinates O and the circular arc plane normal vector e; The solving equation group of the center point coordinates is: wherein: U represents a middle point of a line connecting the weld space location point A and the weld space location point B; V represents a middle point of a line connecting the weld space location point B and the weld space location point C; , , , , , , all represent directional vectors; · represents a vector dot product operator symbol; x represents a vector cross product operator symbol; The expression of the circular arc plane normal vector e is 。 3. A multi-layer multi-pass path planning method for a space ring weld according to claim 2, wherein, The S4 specifically comprises the following steps: S41: Obtain the circular arc degree θ of each weld segment, and obtain the rotation matrix Q according to the circular arc plane normal vector e, and the obtaining formula of the rotation matrix Q is In the formula: I represents a 3x3 unit matrix; E represents the skew-symmetric matrix of the circular arc plane normal vector e; e1, e2, e3 represent the spatial vector components of the circular arc plane normal vector e; S42: Obtain the position of the breakpoint section at the weld segment and the welding gun attitude at the corresponding breakpoint section according to the rotation matrix Q based on the preset welding starting point and the initial attitude of the welding gun; The obtaining formula of the position of the breakpoint section at the weld segment is In the formulae: denotes the position of the breakpoint section of the weld segment; denotes a preset welding starting point; The obtaining formula of the welding gun attitude at the corresponding breakpoint section is In the formulae: denotes the welding torch pose at the corresponding breakpoint section; denotes the welding torch initial pose.

4. A multi-layer multi-pass path planning method for a space ring weld according to claim 3, wherein, The S5 specifically comprises the following steps: S51: defining each weld segment to include several layers of multi-pass weld beads, defining the weld segment k as the middle segment between the breakpoint section k and the breakpoint section k+1, and defining the first layer weld bead in the weld segment k as the first layer weld bead in the middle segment k. The weld start point and the weld end point of the layer weld bead are defined as , respectively. S52: According to the cross-sectional height of the weld cross section, confirm the first layer welding pass welding torch lifting height; and the first The expression for the height of the welding torch lift for a layer weld bead is In the formulae: represents the first layer of weld beads; represents the thickness of the first layer of weld beads defined according to the cross-sectional height; S53: Obtain the center point coordinate O to the section position of the breakpoint section k the direction vector of ; and the obtaining formula of the direction vector of ​ According to the direction vector The extension vector OB is obtained, and the obtaining formula of the extension vector OB is S54: According to the center point coordinate O and the extension vector OB, the first The expression of the weld starting point of the layer weld is According to the center point coordinate O and the first The height of the welding torch is raised to obtain the end point of the welding bead of the first The expression of the end point of the welding bead of the first 。 5. A multi-layer multi-pass path planning method for a space ring weld according to claim 4, wherein, It also includes Z-type weaving welding for each layer welding bead in the multi-layer multi-pass path of the annular weld; and the weaving amplitude of the Z-type weaving welding by the welding gun is the bead width, and the calculation formula of the bead width is In the formulae: represents the first represents the bead width of the layer weld bead; represents the top width; represents the base angle of the isosceles trapezoid formed by the base width, the top width, and the cross-sectional height.

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