A method for automatically generating a hydraulic support side guard welding program based on an MBD three-dimensional model and a parameterized trajectory

Abstract

This invention provides a method for automatically generating welding programs for hydraulic support side plates based on MBD 3D models and parametric trajectories. The method includes: establishing a side plate weld trajectory library and a standard program text library; establishing a coordinate system; establishing a parametric trajectory library; obtaining parameters from the 3D model; matching parametric trajectory templates; generating offline welding programs; assigning coordinate information of each welding program point in the obtained PLM parametric trajectory template to the points in the standard program text through matching relationships, and outputting the offline welding program. This method transforms traditional on-site teaching programming and offline programming into parametric programming based on 3D models, requiring no hardware support, and enabling offline welding programs to be output during product design using MBD parameters.

Description

Technical Field

[0001] This invention relates to the field of hydraulic support manufacturing technology, and more specifically, to a method for automatically generating welding programs for hydraulic support side guard plates based on MBD three-dimensional models and parametric trajectories. Background Technology

[0002] Hydraulic supports, as a crucial piece of equipment in coal mining machinery, are often custom-designed by various companies due to the influence of their operating environment, and production is primarily based on discrete manufacturing. This results in each batch of products requiring a set of compatible technical documentation, such as drawings, processes, and welding procedures. Hydraulic support side plates, in particular, are characterized by a wide variety of types and rapid production changes. Therefore, how to efficiently and effectively program welding robots for side plates has become one of the most pressing challenges for major domestic hydraulic support manufacturers.

[0003] Welding robots are increasingly widely used in manufacturing, and their stable welding quality and efficient production continuity are gaining increasing recognition from enterprises. For structural components like hydraulic support side plates, which are multi-variety and have rapid production changeover cycles, traditional on-site teaching programming and offline programming suffer from high manual intervention, low programming efficiency, and a high risk of errors. Currently, MBD (Model Based Definition) technology is being developed and applied in the coal mining machinery field, providing a technological foundation for the automatic generation of welding programs for hydraulic support side plates based on 3D models and parametric trajectories. This method of combining the geometric parameters of the 3D model with parametric welding trajectories to generate welding programs will significantly reduce the pressure of product production cycles and welding program quality issues, meeting the high-quality and efficient requirements of modern manufacturing for technical data preparation.

[0004] Chinese invention patent "A Parametric Programming System and Programming Method for a Box Welding Robot" (application number: CN201811557908) was published on April 16, 2019. This invention describes a parametric programming system and programming method for a box welding robot, including: a host computer for storing electronic spreadsheets containing geometric feature parameters and process parameter specifications of large box structures; a host computer APP program for inputting data into the electronic spreadsheets and sending data; a PLC connected to the host computer APP program via a local area network, including a slave PLC and a master PLC, wherein the slave PLC receives data sent by the host computer APP program and the master PLC sends data reception requests; and a robot controller connected to the master PLC via an I / O PTP and to the slave PLC via a fieldbus, and automatically generates a welding process table based on the received data, thereby completing the programming of the box welding robot welding task program.

[0005] The solution has the following four main drawbacks: 1. It requires a large number of hardware devices with high requirements and large procurement costs; 2. It requires manual input of the box's geometric features and process parameters through the human-machine interface, which poses a risk of errors; 3. The program cannot be programmed offline, affecting production changeover efficiency; 4. It has a narrow scope of application, only suitable for box welding.

[0006] In order to solve the above problems, people have been seeking an ideal technological solution. Summary of the Invention

[0007] The purpose of this invention is to address the shortcomings of existing technologies by providing a method that converts traditional on-site teaching programming and offline programming into parametric programming based on three-dimensional models. This method requires no hardware support and can automatically generate welding programs for hydraulic support side guard plates by outputting offline welding programs through MBD parameters during product design.

[0008] To achieve the above objectives, the technical solution adopted by this invention is: a method for automatically generating a welding program for a hydraulic support side guard plate based on an MBD three-dimensional model and parametric trajectory, comprising the following: Establish a side guard plate weld trajectory library and a standard procedure text library: Based on the structural characteristics and welding process of the side guard plate, a side guard plate weld trajectory library was established; Based on the side guard plate weld trajectory library, establish a standard program text library for each weld trajectory; Establish coordinate system correspondence: Establish the tooling coordinate system of the welding robot positioner and obtain the positional relationship between the tooling coordinate system and the welding robot world coordinate system; Construct the workpiece assembly coordinate system, clarify its positional relationship with the tooling coordinate system and the world coordinate system, obtain the specific data of the workpiece assembly coordinate system and store it in the specified numerical register; Establish a parametric trajectory library: A parameterized trajectory library is compiled based on the weld trajectory library and the coordinate correspondence. A point on each weld trajectory is selected as a feature point of the weld trajectory. The coordinates of the feature point are used as a reference and a corresponding numerical register number is assigned. Then, the coordinates of the feature points of each weld trajectory and the geometric features of all the parts that make up the weld trajectory are combined to convert the coordinate values ​​of each point in the weld trajectory into a functional relationship to form a parameterized trajectory library. With all libraries established, we move into the application phase: First, the computer-aided design software reads the 3D model of the input side guard plate. The computer-aided design software then uses its own functions to parse the coordinate values ​​of the weld trajectory feature points on each weld seam in the 3D model relative to the assembly coordinate system, as well as the geometric feature information of the side guard plate. Alternatively, the coordinate values ​​of the weld trajectory feature points on each weld seam in the 3D model relative to the assembly coordinate system can be determined manually in conjunction with the computer-aided design software, and the geometric feature information of the side guard plate can be obtained by the computer-aided design software itself. Matching parameterized trajectory templates: The 3D model of the side guard plate with parameters is imported into the PLM system. The PLM system's process platform reads the coordinate values ​​of each weld trajectory feature point in the 3D model relative to the assembly coordinate system and the geometric feature information of the side guard plate. The PLM system calls the corresponding weld trajectory information from the weld trajectory library and then calls the functional relationship used to indicate each weld trajectory from the parameterized trajectory library. The corresponding PLM parameterized trajectory template is manually retrieved and matched, and the parameters are mapped to the corresponding PLM parameterized trajectory template. The coordinate information of each welding program point in the PLM parameterized trajectory template is obtained through the calculation of the functional relationship in the PLM parameterized trajectory template. Generate offline welding program: The coordinate information of each welding program point in the obtained PLM parameterized trajectory template is used to assign values ​​to the points in the standard program text through matching relationships, and the offline welding program is output.

[0009] This invention divides the welding trajectory of the side guard plate according to its characteristics to form a side guard plate weld trajectory library. Then, it establishes a standard program text library based on the process of each weld, sorts out and establishes the coordinate transformation relationship between the weld trajectory and the welding robot system, and uses this to establish a parameterized trajectory library for function-based transformation of the weld trajectory. In specific applications, computer-aided design software obtains the 3D model of the side guard plate part, parses the required parameter values, and inputs them into the PLM system. The PLM system obtains the feature point parameters of each weld trajectory, as well as the corresponding geometric feature information of the part, and retrieves the corresponding parameters from the weld trajectory library. The corresponding weld trajectory is obtained, and then the specific coordinates of the weld trajectory are determined from the parametric trajectory library. The parametric trajectory template is retrieved and matched manually. The coordinate information of each welding program point in the parametric trajectory template is obtained by using the function relation calculation built into the PLM system. Finally, the points in the standard program text are assigned values ​​and the offline welding program is output. This completes the processing of welding parameter information, weld trajectory coordinate information and standard program integration, improves the output efficiency of the side guard plate weld welding program, reduces the design difficulty, and is implemented entirely based on existing software and hardware, so the modification cost is also lower.

[0010] Based on the above, the side guard plate weld trajectory library is obtained through the following method: Based on the structural characteristics of the side guard plate, the geometric positional relationship between the parts is analyzed. Combined with the welding process, the side guard plate welds are manually merged and divided to form weld trajectories containing different characteristics. Each type of weld trajectory is assigned a trajectory number that can express the weld characteristics, and a side guard plate weld trajectory library is established.

[0011] Based on the above method, the structural characteristics of the side guard plate are based on certain rules. The main differences lie in the size or shape differences in local locations. Therefore, the established weld trajectory library can summarize the weld trajectory of the side guard plate.

[0012] Based on the above, the standard program text library was established using the following method: Based on the established side guard plate weld trajectory library, and in conjunction with welding specifications and welding processes, standard program texts that robots can recognize are created for the weld trajectories in each weld trajectory library.

[0013] This division method allows the complete program to be broken down into several standard programs, each corresponding to a weld trajectory.

[0014] Based on the above, the standard program text includes: welding auxiliary program, positioning program, numerical register number, position register number, welding parameters, and number of welding points.

[0015] Based on the above, the specific position of the tooling coordinate system = tooling coordinate system - world coordinate system; the workpiece assembly coordinate system is determined based on the tooling coordinate system. In most cases, the workpiece assembly coordinate system = tooling coordinate system, but in other offset situations, coordinate system offsets may occur. It is mainly used for the transformation and determination of coordinate relationships, enabling the unification and matching of parameters based on coordinates.

[0016] Based on the above, during the process of establishing the parametric trajectory library, after obtaining the position coordinates of each point, the standard welding torch pose WPR value for the corresponding point is input. This is mainly used to input additional information; the WPR value refers to the angle of the welding torch around its internal axis.

[0017] Based on the above, the computer-aided design software used is CAD, and an interface for reading the side guard plate parameter list was developed in CAD. CAD software has good scalability and wide applicability, and can solve the problem of combining three-dimensional models that this application aims to address.

[0018] Based on the above, different weld trajectories include at least one of the following: straight line trajectory, straight line + circular arc trajectory, circular arc + circular arc trajectory, and straight line + circular arc + straight line trajectory.

[0019] This invention has outstanding substantive features and significant progress compared to the prior art. Specifically, the entire processing method of this invention is based on existing hardware infrastructure and does not require additional hardware equipment. This not only simplifies the modification process but also saves on investment funds. The solution utilizes the capabilities of existing computer-aided design software and PLM systems. The amount of data input by humans is very limited, and human resources are only used for selection, matching, and other tasks, which greatly reduces the risk of errors. The welding offline program generated by the above process significantly improves changeover efficiency. Attached Figure Description

[0020] Figure 1 This is a flowchart of the method for automatically generating the welding program of the hydraulic support side guard plate based on the MBD three-dimensional model and parameterized trajectory in this invention.

[0021] Figure 2 This is a flowchart of the process from model creation to outputting the welding program in this invention.

[0022] Figure 3 A schematic diagram illustrating the differences between the two types of trajectory numbering in this invention. Detailed Implementation

[0023] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0024] like Figure 1 As shown, a method for automatically generating welding programs for hydraulic support side guard plates based on MBD 3D models and parametric trajectories includes the following: Establish a side guard plate weld trajectory library and a standard procedure text library: Based on the structural characteristics and welding process of the side guard plate, a side guard plate weld trajectory library was established.

[0025] Specifically, in this embodiment, based on the structural characteristics of the hydraulic support side guard plate, the geometric positional relationship between the parts is analyzed. Combined with the welding process, the weld seams of the side guard plate are artificially merged and divided to form weld seam trajectories containing different characteristics. Each type of weld seam trajectory is assigned a trajectory number that expresses the weld seam characteristics, thus establishing a side guard plate weld seam trajectory library. Figure 3 The diagram illustrates the difference between the two trajectory numbering methods: L-XA-F represents a straight weld, while LRL-XA-F represents a straight weld with an arc. In practical implementation, the weld can be roughly decomposed into at least the following forms: straight trajectory, straight + arc trajectory, arc + arc trajectory, and straight + arc + straight trajectory.

[0026] Based on the side guard plate weld trajectory library, establish a standard program text library for each weld trajectory.

[0027] Specifically, in this embodiment, based on the side guard plate weld trajectory library and in conjunction with welding specifications and welding processes, a standard program text that the robot can recognize is established for each weld trajectory in the weld trajectory library. The standard program text includes: welding assistance program, positioning program, numerical register number, position register number, welding speed, welding parameters, weld leg size, number of welding points, etc. The standard program text is as follows: 1: CALL JIAN_SI; 2: UFRAME_NUM=1; 3: UTOOL_NUM=1; 4: R

[10] =5; 5:JP[1] 10% FINE ; 6: Search Start [1] PR

[25] ; 7:LP[2] 300mm / sec FINE ; 8:LP[2] 300mm / sec FINE Search[X]; 9: Search End; 10:LP[3] 300mm / sec FINE ; 11: CALL K8_JH_PB_Q6_A(0); 12: Touch Offset PR

[25] ; 13:LP[4] 50mm / sec FINE Weld Start[3,1] ; 14:LP[5] WELD_SPEED FINE : Weld End[3,1,WID:0] ; 15: Touch Offset End; 16:LP[6] 300mm / sec FINE ; Establish coordinate system relationships: Establish the tooling coordinate system of the welding robot positioner and obtain the positional relationship between the tooling coordinate system and the welding robot world coordinate system.

[0028] In this embodiment, the tooling coordinate system of the welding robot positioner is represented as (x1, y1, z1). The positional relationship between the tooling coordinate system and the welding robot world coordinate system (x0, y0, z0) is measured, and the specific position of the tooling coordinate system is calculated: C(c1, c2, c3) = tooling coordinate system (x1, y1, z1) - world coordinate system (x0, y0, z0).

[0029] Construct the workpiece assembly coordinate system (x2, y2, z2), clarify its positional relationship with the tooling coordinate system, obtain the specific data of the workpiece assembly coordinate system, and assign it to the specified value register: In this embodiment, the assembly coordinate system (x2, y2, z2) = the tooling coordinate system (x1, y1, z1) = C(c1, c2, c3) Numerical registers: Rn1=c1, Rn2=c2, Rn3=c3.

[0030] Establish a parametric trajectory library: A point on the weld trajectory is selected as a feature point of the weld trajectory. Based on the coordinates (Xn, Yn, Zn) of the feature point, corresponding numerical register numbers are assigned: Rn4=Xn, Rn5=Yn, Rn6=Zn. Then, the numerical register operation function relationship is established by reasoning based on the geometric features of all parts that make up the weld trajectory, so as to obtain the position coordinates of each point. The standard gun posture WPR value (welding gun angle around the internal axis) of the corresponding point is input to establish a parameterized trajectory library. The geometric features of the parts include plate thickness, length, width, arc radius, angle, etc. Feature point location: PR[X] = Rn1 + Rn4 PR[Y] = Rn2 + Rn5 PR[Z]=Rn3+Rn6.

[0031] It should be noted that, in this embodiment, the core of the parameterized trajectory library is to convert the coordinate values ​​of each point in the weld trajectory into a functional relationship. The library itself does not store specific coordinate values, but stores functional relationships so that the actual weld trajectory coordinates can be calculated based on the coordinate information of the actual input parts when applied.

[0032] In the application phase, parameters are obtained from the 3D model: like Figure 2 As shown, the actual 3D model of the side guard plate to be welded is entered. In the CAD (Computer Aided Design) software, a parameter list reading interface for the side guard plate is developed. The coordinate values ​​(Cn1, Cn2, Cn3) of each weld trajectory feature point relative to the assembly coordinate system are stored in the CAD 3D model parameters. At the same time, the geometric parameter information of the side guard plate 3D model is available from the CAD itself.

[0033] In other embodiments, the coordinate values ​​of the weld trajectory feature points relative to the assembly coordinate system can be determined by the CAD itself or by manual determination.

[0034] The 3D model of the side guard plate with parameters is imported into the PLM system. The PLM system's process platform reads the coordinate values ​​of each weld trajectory feature point in the 3D model relative to the assembly coordinate system and the geometric feature information of the side guard plate. The PLM system calls the corresponding weld trajectory information from the weld trajectory library and then calls the functional relationship used to indicate each weld trajectory from the parameterized trajectory library. The corresponding PLM parameterized trajectory template is manually retrieved and matched, and the parameters are mapped to the corresponding PLM parameterized trajectory template. The coordinate information of each welding program point in the PLM parameterized trajectory template is obtained through the calculation of the functional relationship in the PLM parameterized trajectory template. Generate offline welding program: The coordinate information of each welding program point in the obtained PLM parameterized trajectory template is used to assign values ​​to the points in the standard program text through matching relationships, and the offline welding program is output.

[0035] The matching relationship refers to the number of welding program points in the parameterized trajectory template and the number of points in the standard program text arranged in sequence.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can still be made to the specific implementation of the present invention or equivalent substitutions can be made to some technical features without departing from the spirit of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the technical solutions claimed in the present invention.

Claims

1. A method for automatically generating welding programs for hydraulic support side guard plates based on MBD 3D models and parametric trajectories, characterized in that: Includes the following: Establish a side guard plate weld trajectory library and a standard procedure text library: Based on the structural characteristics and welding process of the side guard plate, a side guard plate weld trajectory library was established; Based on the side guard plate weld trajectory library, establish a standard program text library for each weld trajectory; Establish coordinate system correspondence: Establish the tooling coordinate system of the welding robot positioner and obtain the positional relationship between the tooling coordinate system and the welding robot world coordinate system; Construct the workpiece assembly coordinate system, clarify its positional relationship with the tooling coordinate system and the world coordinate system, obtain the specific data of the workpiece assembly coordinate system and store it in the specified numerical register; Establish a parametric trajectory library: A parameterized trajectory library is compiled based on the weld trajectory library and the coordinate correspondence. A point on each weld trajectory is selected as a feature point of the weld trajectory. The coordinates of the feature point are used as a reference and a corresponding numerical register number is assigned. Then, the coordinates of the feature points of each weld trajectory and the geometric features of all the parts that make up the weld trajectory are combined to convert the coordinate values ​​of each point in the weld trajectory into a functional relationship to form a parameterized trajectory library. With all libraries established, we move into the application phase: First, the computer-aided design software reads the three-dimensional model of the input side guard plate. The computer-aided design software then uses its own functions to parse the coordinate values ​​of the weld trajectory feature points on each weld in the three-dimensional model relative to the assembly coordinate system, as well as the geometric feature information of the side guard plate. Alternatively, the coordinate values ​​of the weld trajectory feature points on each weld in the 3D model relative to the assembly coordinate system can be determined manually in combination with computer-aided design software, and the geometric feature information of the side guard plate can be obtained by the computer-aided design software itself. Matching parameterized trajectory templates: The 3D model of the side guard plate with parameters is imported into the PLM system. The PLM system's process platform reads the coordinate values ​​of each weld trajectory feature point in the 3D model relative to the assembly coordinate system and the geometric feature information of the side guard plate. The PLM system calls the corresponding weld trajectory information from the weld trajectory library and then calls the functional relationship used to indicate each weld trajectory from the parameterized trajectory library. The corresponding PLM parameterized trajectory template is manually retrieved and matched, and the parameters are mapped to the corresponding PLM parameterized trajectory template. The coordinate information of each welding program point in the PLM parameterized trajectory template is obtained through the calculation of the functional relationship in the PLM parameterized trajectory template. Generate offline welding program: The coordinate information of each welding program point in the obtained PLM parameterized trajectory template is used to assign values ​​to the points in the standard program text through matching relationships, and the offline welding program is output.

2. The method for automatically generating a welding program for a hydraulic support side guard plate based on an MBD three-dimensional model and parametric trajectory as described in claim 1, characterized in that: The side guard plate weld trajectory library was obtained through the following method: Based on the structural characteristics of the side guard plate, the geometric positional relationship between the parts is analyzed. Combined with the welding process, the side guard plate welds are manually merged and divided to form weld trajectories containing different characteristics. Each type of weld trajectory is assigned a trajectory number that can express the weld characteristics, and a side guard plate weld trajectory library is established.

3. The method for automatically generating a welding program for a hydraulic support side guard plate based on an MBD three-dimensional model and parametric trajectory according to claim 1, characterized in that: The standard program text library was established using the following method: Based on the established side guard plate weld trajectory library, and in conjunction with welding specifications and welding processes, standard program texts that robots can recognize are created for the weld trajectories in each weld trajectory library.

4. The method for automatically generating the welding program for the side guard plate of a hydraulic support based on MBD three-dimensional model and parametric trajectory according to claim 3, characterized in that: The standard program text includes: welding auxiliary program, positioning program, numerical register number, position register number, welding parameters, and number of welding points.

5. The method for automatically generating a welding program for a hydraulic support side guard plate based on an MBD three-dimensional model and parametric trajectory according to claim 1, characterized in that: The specific position of the tooling coordinate system = tooling coordinate system - world coordinate system; the workpiece assembly coordinate system is determined based on the tooling coordinate system.

6. The method for automatically generating a welding program for a hydraulic support side guard plate based on an MBD three-dimensional model and parametric trajectory according to claim 1, characterized in that: In the process of establishing the parametric trajectory library, after obtaining the position coordinates of each point, the standard gun position WPR value of the corresponding point is also input.

7. The method for automatically generating a welding program for a hydraulic support side guard plate based on an MBD three-dimensional model and parametric trajectory according to claim 1, characterized in that: The computer-aided design software used is CAD, and an interface for reading the side guard plate parameter list was developed in CAD.

8. The method for automatically generating a welding program for a hydraulic support side guard plate based on an MBD three-dimensional model and parametric trajectory according to claim 1 or 2, characterized in that: Different weld seam trajectories include at least one of the following: straight line trajectory, straight line + circular arc trajectory, circular arc + circular arc trajectory, and straight line + circular arc + straight line trajectory.

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