WO2022213374A1

WO2022213374A1 - Welding system and welding parameter optimization method

Info

Publication number: WO2022213374A1
Application number: PCT/CN2021/086227
Authority: WO
Inventors: 林其禹; 库马尔拜达克•阿密特
Original assignee: 迅智自动化科技股份有限公司; 虹朗科技股份有限公司
Priority date: 2021-04-09
Filing date: 2021-04-09
Publication date: 2022-10-13

Abstract

A welding parameter optimization method, comprising the following steps: determining the structural size of two or more weldments in a digital three-dimensional model and the geometric shape at the connection thereof; determining a motion trajectory and welding parameters of a welding gun according to the structural size of the weldments and the geometric shape at the connection thereof, and planning the correspondence between the motion trajectory and the welding parameters, wherein the digital three-dimensional model corresponds to a real object, the motion trajectory corresponds to an action path of the welding gun, the welding parameters are related to at least one among power characteristics and moving speed, and the correspondence is used for controlling the welding gun to operate on the real object. Using the welding parameter optimization method can improve welding quality. Further provided is a welding system.

Description

Welding system and welding parameter optimization method

technical field

The invention relates to a welding technology, in particular, to a welding system and a welding parameter optimization method.

Background technique

Welding is a widely used process and technique and may be used to manufacture a variety of products such as automobiles, bicycles, sports equipment, mechanical structures, appliances or furniture. It is worth noting that today's welding operations are very dependent on operator experience. Inexperienced operators may cause defects such as damaged weldments or weak connections. In fact, there are many variables in the welding operation, and these variables can affect the quality of the finished product. For example, the thicknesses of the two objects to be welded into one object may be different, and the angle formed by the two adjacent objects at any welding point may also be different at different places. Therefore, each welding point may have different thicknesses of adjacent objects and different angles formed by the two objects. Therefore, if the moving speed of the welding torch is known in advance, the welding optimization parameters corresponding to the welding point (for example, the welding torch device voltage and current) will also vary. If the voltage and current settings of the welding gun are not good, the heat fusion effect of two adjacent objects during welding will be reduced. This phenomenon is not due to insufficient temperature in the area to be welded, which leads to poor welding effect, or overheating, which causes the object to be welded in the area to be melted excessively, and also causes structural damage to the object. However, most manual welding operators typically choose a single torch travel speed and choose to weld with the same set of welding parameters (eg, current and voltage) throughout the welding trajectory. Because manual welding is used, the user cannot change the voltage and current in real time with different welding points.

In addition, the use of robotic arms to perform welding is an industry trend, and many software can automatically generate the trajectories required for robotic arms to perform welding. However, under the premise of not knowing the thickness of the object adjacent to each welding point on the welding track and the angle formed by the two adjacent objects, it is impossible to optimize the welding parameters (such as voltage and current) corresponding to each welding point. ) is associated with the welding track. Therefore, even if the software generates the welding track of the robot arm, the parameter setting of the welding torch can only be manually set to the same group or a few different groups based on experience, and it is impossible for each welding point to be based on the actual conditions of the adjacent objects. The thickness and the angle formed by the adjacent objects select a corresponding optimization parameter combination. In this way, the effect of welding cannot be optimized, and the mechanical strength of the structure after welding is theoretically deteriorated, making it more difficult to improve.

SUMMARY OF THE INVENTION

The invention aims at a welding system and a welding parameter optimization method, and analyzes the optimal welding parameter combination suitable for each track line to be welded, thereby improving the welding quality.

According to an embodiment of the present invention, the welding parameter optimization method includes (but is not limited to) the following steps: determining the structural dimensions of two or more weldments (objects to be welded into a structure) in a digital three-dimensional model and their connections (corresponding to one or more trajectories to be welded), determine the trajectory of the robot arm carrying the welding torch and/or the robot arm or the motion platform holding the object to be welded according to these trajectories to be welded, and plan Welding parameters corresponding to different motion trajectory points. This digital solid model corresponds to a real object. The motion trajectory is related to the motion path of the robot arm carrying the welding gun, and the movement trajectory of the robot arm or the motion platform carrying the object to be welded, and the welding parameters are related to at least one of power characteristics and moving speed. This correspondence is used to control the operation of the welding torch to the real object.

According to an embodiment of the present invention, a welding system includes, but is not limited to, a welding gun, a welding gun controller, and a control device. Welding torches are used for welding. The welding torch controller is coupled to the welding torch and used to control the operation of the welding torch. The control device is coupled to the welding torch controller, and is used to determine the structural dimensions of two or more weldments in the digital three-dimensional model and the geometrical shapes of their joints, which are determined according to the structural dimensions of these weldments and the geometrical shapes of their joints The motion trajectory and welding parameters of the welding torch, and the corresponding relationship between the motion trajectory and the welding parameters are planned. This digital solid model corresponds to a real object. The motion trajectory is related to the action path of the welding gun, and the welding parameters are related to at least one of electric power characteristics and moving speed. This correspondence is used to control the operation of the welding torch to the real object.

Based on the above, the welding system and the welding parameter optimization method according to the embodiment of the present invention analyze the structural shape of the digital three-dimensional model corresponding to the real object, and obtain appropriate welding parameters for each trajectory to be welded accordingly. Then, these welding parameters are associated with the motion trajectory of the welding gun one-to-one, so that the welding parameters can be switched during the operation and movement of the welding gun. In this way, welding parameters corresponding to different joints to be welded can be quickly obtained, which not only improves the efficiency, but also improves the welding quality.

Description of drawings

The accompanying drawings are included to provide a further understanding of the present invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and together with the description serve to explain the principles of the invention.

1 is a block diagram of components of a welding system according to an embodiment of the present invention;

FIG. 2 is a flowchart of a welding parameter optimization method according to an embodiment of the present invention;

FIG. 3 is an exemplary illustration of a digital three-dimensional model;

Fig. 4A is a partial enlarged view of Fig. 3;

FIG. 4B is an included angle corresponding to several adjacent points in FIG. 4A .

Explanation of reference numerals

100: welding system;

5: real object;

10: welding gun;

30: welding torch controller;

50: mobile mechanism;

70: control device;

71: memory;

7: digital three-dimensional model;

73: processor;

S210～S250: steps;

t1, t2, t3, t4: weldment;

c1, c2, c3, c4: the connection point;

np1, np2, np3, np4: adjacent points;

θ1, θ2, θ3, θ4: included angles.

Detailed ways

Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals are used in the drawings and description to refer to the same or like parts.

FIG. 1 is a block diagram of components of a welding system 100 according to an embodiment of the present invention. Referring to FIG. 1 , the welding system 100 includes (but is not limited to) a welding torch 10 , a welding torch controller 30 , a moving mechanism 50 , and a control device 70 .

The welding torch 10 can be powered by an energy source such as an arc, laser, or electron beam, and is used to perform welding operations.

The welding torch controller 30 is coupled to the welding torch 10 and used to control the operation of the welding torch 10 . In one embodiment, the welding gun controller 30 controls the electrical characteristics of the power supplied to the welding gun 10 . The power characteristic can be voltage, current, or a combination thereof. For example, in an arc welding process, the voltage supplied to the torch 10 determines the length of the arc, and the current input determines the heat output.

The movement mechanism 50 is used for the placement of the real object 5 (ie, the object to be welded; eg, a bicycle, automobile, mechanical structure, part of an appliance or furniture) and/or the welding gun 10 . For example, the moving mechanism 50 grips, abuts, or supports the real object 5 or the welding gun 10 . The moving mechanism 50 can be one or more groups of multi-axis robotic arms, multi-degree-of-freedom mechanisms, height adjustment tables, slide rails, turntables, screws, motors, or cylinders, etc. It is combined to drive the real object 5 and/or the welding torch 10 placed thereon to lift, move and/or rotate.

The control device 70 is wired or wirelessly coupled to the welding torch controller 30 and the moving mechanism 50, and the control device 70 may be a desktop computer, a smart phone, a tablet computer, a workstation, a host computer, or other devices. The control device 70 includes (but is not limited to) a memory 71 and a processor 73 .

The memory 71 can be any type of fixed or removable random access memory (Radom Access Memory, RAM), read only memory (Read Only Memory, ROM), flash memory (flash memory), traditional hard disk (Hard Disk Drive, HDD) , Solid-State Drive (SSD) or similar components, and used to record program codes, software modules, digital three-dimensional models 7 corresponding to real objects 5, motion trajectories, welding parameters, their corresponding relationships, welding torch controller 30 and The driver program and other data or files of the moving mechanism 50 will be described in detail in subsequent embodiments.

The processor 73 may be a central processing unit (Central Processing Unit, CPU), a graphics processing unit (Graphic Processing Unit, GPU), a micro control unit (Micro Control Unit, MCU), or a special application integrated circuit (Application-Specific Integrated Circuit, ASIC) and other arithmetic units, and are used to execute all operations of the control device 70 . For example, a control command is generated and transmitted to the welding gun controller 30 or the moving mechanism 50 to control the cooperative operation or action of the welding gun controller 30 or the moving mechanism 50 , the detailed operation of which will be described in detail in subsequent embodiments.

In some embodiments, the control device 70 may further include a display such as a Liquid Crystal Display (LCD), a Light-Emitting Diode (LED) display, or an Organic Light-Emitting Diode (OLED) display, etc. display and provide the user interface. The user interface may present the digital solid model 7, welding parameters of the welding torch 10, motion trajectories and/or user input fields.

Furthermore, in some embodiments, at least two of the welding gun 10, the welding gun controller 30, the moving mechanism 50, and the control device 70 may be integrated into one body or be separate devices.

In order to facilitate the understanding of the operation process of the embodiment of the present invention, the following will describe in detail the operation process of the welding system 100 in the embodiment of the present invention by referring to various embodiments. Hereinafter, the method according to the embodiment of the present invention will be described in conjunction with various devices, components and modules in the welding system 100 . Each process of the method can be adjusted according to the implementation situation, and is not limited to this.

FIG. 2 is a flowchart of a welding parameter optimization method according to an embodiment of the present invention. Referring to FIG. 2 , the processor 73 of the control device 70 determines the structural dimensions of two or more weldments in the digital three-dimensional model 7 and the geometrical shapes of one or more joints (step S210 ). In particular, the digital solid model 7 is stereographic data corresponding to the real object 5 (eg, a solid object formed from images, objects, CAD data or point cloud data). That is, the digital solid model 7 has the same or similar shape and appearance as the real object 5 .

For example, please refer to FIG. 3 to illustrate an example of the digital three-dimensional model 7 . The digital solid model 7 is part of the bicycle skeleton (ie the real object 5 is the bicycle skeleton). The weldments t1, t2, t3, t4 in the digital solid model 7 represent the parts (eg, aluminum alloy rods) to be welded in the bicycle frame. These weldments t1, t2, t3, t4 are connected to each other in pairs. The phase connection c1 is formed between the weldments t1 and t2, the phase connection c2 is formed between the weldments t2 and t4, the phase connection c3 is formed between the weldments t3 and t4, and the phase connection c4 is formed between the weldments t1 and t3. The connection position c1 of the weldments t1 and t2 represents the desired connection position of the corresponding two parts of the real object 5 , and accordingly forms the to-be-welded track line. The connection points c2, c3 and c4 can be deduced by analogy.

In one embodiment, the processor 73 may measure the structural dimensions of those weldments and the geometry of the junction between every two or more weldments according to the digital three-dimensional model 7 . For example, the processor 73 can identify weldments and joints and calculate the corresponding shapes. In another embodiment, these structural dimensions and/or geometries may also be pre-defined or set in a specification sheet and recorded in the memory 71 . For example, the processor 73 may read from the memory 71 the specifications used to generate the digital solid model 7 .

It should be noted that, in some embodiments, the user can select a specific number or position of weldments and their connections on the user interface, and the processor 73 can determine the structural dimensions of the selected weldments and the corresponding The geometry of the connection.

In one embodiment, the structural dimensions of those weldments are related to their thickness. That is, the thickness of the part material of the real object 5. On the other hand, the geometry of the connection between the two weldments is related to the angle formed by the two weldments on the line of the track to be welded. For example, please refer to FIG. 4A , which is a partial enlarged view of FIG. 3 (corresponding to the connection point c1 between the weldments t1 and t2 ). The welding parts t1 and t2 include adjacent points np1 , np2 , np3 and np4 at the phase connection c1 (ie, the intersection of the two welding parts t1 and t2 , and the track to be welded is formed accordingly). Next, please refer to FIG. 4B for the included angles θ1 , θ2 , θ3 , and θ4 corresponding to several adjacent points np1 , np2 , np3 , and np4 in FIG. 4A . The included angles θ1 , θ2 , θ3 and θ4 formed by the weldments t1 and t2 at these adjacent points np1 , np2 , np3 and np4 are different.

It should be noted that FIG. 4A and FIG. 4B are only illustrative, and in other embodiments, the number, position and corresponding angle of adjacent points may be different.

Next, the processor 73 determines the motion trajectory and welding parameters of the welding torch 10 according to the structural dimensions of the weldments and the geometrical shapes of the joints (step S230 in FIG. 2 ). Specifically, for the motion trajectory, the motion trajectory is related to the motion path of the welding gun 10 and/or the real object 5 . The processor 73 can plan in advance how the moving mechanism 50 moves to a specific position with a specific attitude at a specific time, or the processor 73 can infer how the welding gun 10 and/or the real object 5 should move based on a look-up table or AI, so that the welding gun 10 can move The corresponding position of the connection to the parts of the real object 5 and the connection can be welded. The stop position, moving direction, moving speed and/or posture of the welding torch 10 and/or the real object 5 during the movement can be used as the content of the movement track.

For welding parameters, on the other hand, the welding parameters are related to electrical characteristics (eg, voltage, current, or a combination thereof) and/or movement speed of the welding torch 10 . It is worth noting that in some welding technical manuals, there are corresponding optimized welding parameters for different structural sizes and geometric shapes. For example, Table (1) is the optimal current and voltage correspondence table under the condition that the welding torch moving speed is 30 cm per minute, under different angles and thicknesses (the values are only used for example description):

Table 1)

In one embodiment, the welding technical manual may be recorded in the memory 71 . In addition, the moving speed can be preselected by the user or the processor 73 can select any one of the moving speeds recorded in the manual. Next, the processor 73 can query the corresponding table of the welding technical manual, and obtain the electrical characteristics and moving speed corresponding to the thickness of the weldment and the angle formed by the connection. When the angle formed by the actual phase connection is not exactly 90° or 180°, interpolation can be used to calculate suitable current and voltage data. Of course, when the included angle of the to-be-welded track lines formed at the connecting places is not exactly 90° or 180°, the closer angle of 90° or 180° can also be directly used as the selection basis. It is worth mentioning that many welding manuals recommend using the thinner of the two weldments as the thickness basis for welding parameter selection. However, for example taking the average of the two thicknesses or other calculation methods can also be performed. It is worth mentioning that, under different values of the moving speed of the welding torch, different combinations of angles and thicknesses may also form a new optimal current and voltage correspondence table.

In another embodiment, the processor 73 may use the contents of the welding technical manual for structural dimensions, geometric shapes and corresponding welding parameters as training samples for machine learning, and establish an inferencer model accordingly. The processor 73 can input the actual structural size of the weldment and the geometrical shape of its connection into the inferencer model, so as to obtain the corresponding electrical characteristics and moving speed.

Next, the processor 73 may plan the corresponding relationship between the motion trajectory and the welding parameters (step S250 in FIG. 2 ). Specifically, the corresponding relationship is used to control the motion trajectory and welding parameters used by the welding torch 10 to operate on the real object 5 . For example, for weldments of different thicknesses, with the welding torch 10 in a first position (assumed to correspond to the junction between the first and second weldments), the torch controller 30 supplies energy to the welding torch using a first voltage and a first current 10, and the moving mechanism 50 drives the welding torch 10 to move at the first speed; the welding torch 10 is in the second position (assuming corresponding to the connection between the second and third weldments), the welding torch controller 30 uses the second voltage and the first Two currents supply energy to the welding gun 10, and the moving mechanism 50 drives the welding gun 10 to move at a second speed.

In one embodiment, for adjacent points with different included angles, the processor 73 may respectively determine the welding operation combination corresponding to those adjacent points on the line of any track to be welded. Each welding operation combination is the corresponding relationship between the position of the welding torch 10 and/or the real object 5 and/or the motion trajectory of the real object 5 corresponding to an adjacent point and the electric power characteristic or the moving speed. The included angles (values) corresponding to different adjacent points may be different, resulting in different electrical characteristics or moving speeds in different combinations of welding operations. Taking FIG. 4A as an example, the welding operation combination is, the welding torch 10 is in the third position (assuming corresponding to the adjacent point np1), the welding torch controller 30 uses the third voltage and the third current to supply energy to the welding torch 10; another welding operation combination Yes, the welding torch 10 is in the fourth position (assumed to correspond to the adjacent point np2 ), and the welding torch controller 30 supplies energy to the welding torch 10 using the fourth voltage and the fourth current.

In one embodiment, the processor 73 may present the planned motion trajectory and the corresponding welding parameters on the user interface or output to other external devices (eg, smart phones, tablet computers, desktop computers, or servers, etc.).

In another embodiment, the processor 73 can control the moving mechanism 50 to drive the real object 5 or the welding torch 10 according to the determined motion trajectory, and generate control commands related to the corresponding relationship. The control command is the power characteristic used by the welding torch controller 30 to supply power to the welding torch 10 when the moving mechanism 50 drives the real object 5 or the welding torch 10 to a specific position recorded by the motion trajectory. The welding torch controller 30 can control the welding torch 10 to perform welding according to the electrical characteristics corresponding to the location according to the control instruction, and the moving mechanism 50 drives the welding torch 10 to move in a specified direction according to the determined moving speed.

To sum up, the welding system and the welding parameter optimization method according to the embodiments of the present invention obtain the structural dimensions of the weldment in the digital three-dimensional model of the real object and the geometrical shape of the joints, and determine the welding torch and/or the real object accordingly. The motion trajectory of the object and the welding parameters used by the welding gun (eg power characteristics and/or movement speed, etc.). Next, each position of the motion trajectory will be associated with a corresponding set of welding parameters to form a corresponding relationship. This correspondence will allow the welding torch to weld at a specific location, on a specific phase connection or even on adjacent points on it, using specific welding parameters. Thereby, suitable welding parameters can be obtained quickly and efficiently, thereby improving the welding quality.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features thereof can be equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention. scope.

Claims

A welding parameter optimization method, comprising:

Determining the structural dimensions of at least two weldments in the digital solid model and the geometrical shapes of the joints, wherein the digital solid model corresponds to a real object;

The motion trajectory and welding parameters of the welding torch are determined according to the structural dimensions of the at least two weldments and the geometrical shape of the connection, wherein the motion trajectory is related to the motion path of the welding gun, and the welding the parameter is related to at least one of an electrical characteristic and a speed of movement of the welding gun; and

A corresponding relationship between the motion trajectory and the welding parameter is planned, wherein the corresponding relationship is used to control the welding gun to operate on the real object.
The welding parameter optimization method according to claim 1, wherein the track line to be welded is formed by the connection of the two welding parts, the structural size of the two welding parts is related to its thickness, and the The geometric shape of the connection is related to the angle formed by the two weldments on the track to be welded, and is based on the structural dimensions of the at least two weldments and the geometry of the connection The shape determines the motion trajectory and welding parameters of the welding torch, including:

Obtain the electrical characteristics and the moving speed corresponding to the thickness of the two weldments and the included angle formed by the connection.
The welding parameter optimization method according to claim 2, wherein the electrical characteristic is at least one of voltage or current.
The welding parameter optimization method according to claim 2, wherein the connection of the two weldments includes at least two adjacent points, and the two weldments are formed at the at least two adjacent points. At least two included angles are different, and the step of planning the corresponding relationship between the motion trajectory and the welding parameter includes:

Welding operation combinations corresponding to the at least two adjacent points are respectively determined, wherein each welding operation combination is a combination of the position corresponding to the adjacent point and the electric power characteristic or the moving speed in the motion trajectory. the corresponding relationship, and the power characteristics or the moving speed are different in different combinations of the welding operations.
The welding parameter optimization method according to claim 1, wherein after the step of planning the corresponding relationship between the motion trajectory and the welding parameter, the method further comprises:

A control instruction related to the corresponding relationship is generated, wherein the control instruction is used to instruct the welding torch to perform welding according to the electric power characteristic corresponding to the location.
A welding system, characterized in that it includes:

welding torch, for welding;

a welding gun controller, coupled to the welding gun, and used to control the operation of the welding gun; and

a control device, coupled to the welding torch controller, and used to:

Determining the structural dimensions of at least two weldments in the digital solid model and the geometrical shapes of the joints, wherein the digital solid model corresponds to a real object;

According to the structural dimensions of the at least two weldments and the geometrical shape of the joints, the motion trajectory and welding parameters of the welding torch, wherein the motion trajectory is related to the motion path of the welding torch, and the Welding parameters are related to at least one of electrical characteristics and movement speed of the welding gun; and

A corresponding relationship between the motion trajectory and the welding parameter is planned, wherein the corresponding relationship is used to control the welding gun to operate on the real object.
The welding system according to claim 6, wherein the to-be-welded track line is formed by the connection of the two welding parts, the structural dimension of the two welding parts is related to the thickness thereof, and the connected parts are The geometric shape at the position is related to the included angle formed by the two weldments on the line of the to-be-welded track, and the control device is also used to obtain the thickness of the two weldments and the angle formed at the connection place of the two weldments. The electric power characteristic and the moving speed corresponding to the angle.
8. The welding system of claim 7, wherein the electrical characteristic is at least one of voltage or current.
The welding system according to claim 7, wherein the connecting parts of the two welding parts include at least two adjacent points, and at least two adjacent points formed by the two welding parts are formed at the at least two adjacent points. The included angles are different, and the control device is further used to determine welding operation combinations corresponding to the at least two adjacent points, wherein each welding operation combination is a position corresponding to the adjacent points in the motion trajectory The corresponding relationship with the electric power characteristic or the movement speed, and the electric power characteristic or the movement speed is different in different combinations of the welding operations.
The welding system of claim 6, further comprising:

a movement mechanism, coupled to the control device, for placement of the real object or the welding gun, wherein

The control device controls the moving mechanism to drive the real object or the welding torch according to the motion trajectory, and generates a control instruction related to the corresponding relationship, wherein the welding torch controller controls the welding torch according to the control instruction The welding torch performs welding according to the electrical characteristics corresponding to the location.