Industrial robot free-teaching weld seam searching method, device, equipment, storage medium and program product

Abstract

This application discloses a teach-free weld seam positioning method, apparatus, equipment, storage medium, and program product for industrial robots, relating to the field of automation technology. The teach-free weld seam positioning method for industrial robots includes: scanning a preset welding trajectory using a line laser to obtain the line laser scanning trajectory of the preset welding trajectory in the line laser tool coordinate system; transforming the line laser scanning trajectory to determine the tool center point pose of the welding torch end-effector trajectory in the welding torch end-effector coordinate system; and determining the welding point pose of the welding torch based on the tool center point pose. Since the line laser scanning trajectory obtained by scanning the preset welding trajectory using a line laser emitter is recorded, the actual welding torch end-effector trajectory is simulated; by converting the line laser scanning trajectory into the welding torch end-effector tool center point in the welding torch end-effector coordinate system, resource consumption caused by frequent coordinate transformations during welding is avoided, improving system efficiency and stability.

Description

Technical Field

[0001] This application relates to the field of automation technology, and in particular to a method, apparatus, equipment, storage medium, and program product for teaching-free weld seam positioning of industrial robots. Background Technology

[0002] With the development of Industry 4.0 and intelligent manufacturing, industrial robots have been widely used in the welding field. Currently, the most common method for obtaining welding paths for robots is manual teaching. While this method is simple to operate, it suffers from low efficiency, high workload, and insufficient flexibility, making it difficult to meet the needs of multi-variety, small-batch manufacturing. To address these issues, researchers have gradually introduced vision or optical sensing technologies into welding path planning. Among these, the line laser-based weld detection method has attracted attention due to its simple structure, high accuracy, and strong adaptability. Combining a line laser with a camera allows for real-time acquisition of the three-dimensional shape information of the workpiece weld, thus providing data support for the welding robot to generate automated trajectories.

[0003] However, both existing line laser positioning methods have certain limitations. The manual teaching method cannot achieve true teach-free welding and has a low degree of automation. The other method, which defines the line laser beam as the tool coordinate system, requires frequent coordinate system transformations between welding and scanning commands, increasing the workload of programming and debugging. Summary of the Invention

[0004] The main purpose of this application is to provide a method, device, equipment, storage medium and program product for teaching-free weld seam positioning of industrial robots, which aims to solve the technical problem that existing line laser welding requires frequent coordinate system transformation between welding commands and scanning commands, which increases the workload of programming and debugging.

[0005] To achieve the above objectives, this application proposes a teach-free weld seam positioning method for industrial robots. The method is applied to a teach-free weld seam positioning system for industrial robots. The system includes: a welding torch and a line laser emitter; the line laser emitter is positioned and bound to the welding torch for emitting a line laser; the method includes:

[0006] Based on the line laser, a preset welding trajectory is scanned to obtain the line laser scanning trajectory of the preset welding trajectory in the line laser tool coordinate system;

[0007] Based on the line laser scanning trajectory, the tool center point pose of the welding gun end trajectory in the welding gun end coordinate system is determined by conversion.

[0008] The welding point orientation of the welding torch is determined based on the orientation of the tool's center point.

[0009] In one embodiment, the step of determining the welding point pose of the welding torch based on the tool center point pose includes:

[0010] Determine whether the tip of the welding torch can reach the center point of the tool.

[0011] When the tip of the welding torch can reach the center point of the tool, the center point of the tool is taken as the welding point.

[0012] In one embodiment, after the step of determining whether the tip of the welding torch can reach the tool center point pose, the method further includes:

[0013] When the tip of the welding torch cannot reach the tool center point pose, the tool center point pose is rotated incrementally and iterated until the tip of the welding torch can reach the tool center point pose.

[0014] In one embodiment, the step of incrementally rotating and iterating the tool center point pose until the welding torch tip can reach the tool center point pose includes:

[0015] Obtain the Euler angles of the tool center point pose in the coordinate system of the welding torch end;

[0016] The tool center point pose is rotated around the axis according to the Euler angle value to obtain the rotated tool center point pose, and the step of determining whether the welding gun tip can reach the tool center point pose is returned based on the rotated tool center point pose.

[0017] In one embodiment, the step of rotating the tool center point pose about an axis based on the Euler angle values ​​to obtain the rotated tool center point pose includes:

[0018] When the Euler angles are positive, the tool center point pose is rotated counterclockwise around the axis to obtain the rotated tool center point pose; or,

[0019] When the value of the Euler angle is negative, the tool center point pose is rotated clockwise around the axis to obtain the rotated tool center point pose.

[0020] In one embodiment, the step of determining the tool center point pose of the welding torch end trajectory in the welding torch end coordinate system based on the transformation of the line laser scanning trajectory includes:

[0021] Obtain a pre-built spatial transformation model;

[0022] Based on the spatial transformation model, the pose of the scanning point of the line laser scanning trajectory is transformed to obtain the pose of the tool center point of the welding torch end trajectory in the welding torch end coordinate system.

[0023] Furthermore, to achieve the above objectives, this application also proposes an industrial robot teach-free weld seam positioning device, the industrial robot teach-free weld seam positioning device comprising:

[0024] The trajectory scanning module is used to scan a preset welding trajectory based on the line laser to obtain the line laser scanning trajectory of the preset welding trajectory in the line laser tool coordinate system;

[0025] The trajectory conversion module is used to convert the line laser scanning trajectory and determine the tool center point pose of the welding gun end trajectory in the welding gun end coordinate system.

[0026] The positioning module is used to determine the welding point orientation of the welding torch based on the orientation of the tool's center point.

[0027] In addition, to achieve the above objectives, this application also proposes an industrial robot teach-free weld seam positioning device, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the industrial robot teach-free weld seam positioning method as described above.

[0028] In addition, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the industrial robot teach-free weld seam positioning method described above.

[0029] In addition, to achieve the above objectives, this application also provides a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the industrial robot teach-free weld seam positioning method described above.

[0030] One or more technical solutions proposed in this application have at least the following technical effects:

[0031] This application obtains the line laser scanning trajectory of a preset welding trajectory in the line laser tool coordinate system by scanning the preset welding trajectory with a line laser. Based on the line laser scanning trajectory, the tool center point pose of the welding torch end-effector trajectory in the welding torch end-effector coordinate system is determined. The welding point pose of the welding torch is then determined based on the tool center point pose. Since the line laser scanning trajectory obtained by scanning the preset welding trajectory with a line laser emitter is recorded, the actual welding torch end-effector trajectory is simulated. By converting the line laser scanning trajectory into the welding torch end-effector tool center point in the welding torch end-effector coordinate system, a unified perspective is achieved during the welding process, avoiding resource consumption caused by frequent coordinate transformations during welding, and improving system efficiency and stability. Attached Figure Description

[0032] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0033] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a flowchart illustrating an embodiment of the industrial robot weld seam positioning method without teaching in this application.

[0035] Figure 2 This is a flowchart illustrating Embodiment 2 of the industrial robot no-teach weld seam positioning method of this application;

[0036] Figure 3 This is a flowchart illustrating Embodiment 3 of the industrial robot no-teach weld seam positioning method of this application;

[0037] Figure 4 This is a schematic diagram of the module structure of the industrial robot teach-free weld seam positioning device according to an embodiment of this application;

[0038] Figure 5 This is a schematic diagram of the equipment structure of the hardware operating environment involved in the industrial robot teach-free weld seam positioning method in the embodiments of this application.

[0039] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0040] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0041] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0042] The main solution of this application embodiment is: scanning a preset welding trajectory based on a line laser to obtain the line laser scanning trajectory of the preset welding trajectory in the line laser tool coordinate system; transforming the line laser scanning trajectory to determine the tool center point pose of the welding torch end trajectory in the welding torch end coordinate system; and determining the welding point pose of the welding torch based on the tool center point pose.

[0043] In some implementations, the present application embodiments may employ a line laser emitter / sensor physically bound to the welding torch for scanning in the weld seam location method based on line laser.

[0044] In some implementations, embodiments of this application may define the line laser as a robot tool coordinate system and the welding torch as another tool coordinate system. Positioning and path calibration based on the robot tool coordinate system are achieved by switching between the welding command and the line laser scanning command.

[0045] In some embodiments, the present application can replace the line laser tool coordinate system with the welding torch end coordinate system (i.e., the welding torch tool coordinate system) during the positioning process, so that laser positioning and welding operations can be completed in the same tool coordinate system. By unifying the tool coordinate system control method, frequent coordinate transformations between welding commands and scanning commands are avoided, thereby simplifying the system control process and improving welding accuracy and work efficiency. At the same time, for the initially unreachable pose of the welding torch, the reachable pose of the welding torch can be quickly calculated through the designed progressively enhanced rotation iteration method. Through the line laser-based teach-free weld seam positioning method, automatic identification and precise alignment of weld seam positions can be achieved, reducing manual intervention and improving the intelligence and automation level of welding operations. It is especially suitable for automatic welding applications of multi-variety, small-batch, and complex curved surface workpieces. The solution of this application does not require frequent calculation of coordinate system switching, has a short time consumption, and can meet the high real-time requirements of the robot control field, such as the strong real-time requirements within a control cycle of 500us, and can be applied to high-end fields of high-precision welding.

[0046] It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, such as a computer, server, industrial robot control device, etc., or an electronic device or virtual device capable of realizing the above functions. The following description uses an industrial robot teach-free weld seam finding system (hereinafter referred to as the finding system) as an example to illustrate this embodiment and the following embodiments.

[0047] Based on this, the embodiments of this application provide a method for teaching-free weld seam positioning in industrial robots, referring to... Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the industrial robot weld seam positioning method without teaching in this application.

[0048] The method described in this application can be applied to a teach-free welding seam positioning system for industrial robots. This system can include at least a welding torch and a line laser emitter. The line laser emitter can be positioned and bound to the welding torch. This binding can be achieved by fixing it to a specific point on the welding torch, by using a device for fixed connection, or by other binding methods. This application does not limit the specific binding methods described herein.

[0049] In this embodiment, the industrial robot teach-free weld seam positioning method includes steps S10~S30:

[0050] Step S10: Scan the preset welding trajectory based on the line laser to obtain the line laser scanning trajectory of the preset welding trajectory in the line laser tool coordinate system.

[0051] It is understood that the industrial robot teach-free weld seam positioning system in this application embodiment can be a system for realizing intelligent welding of industrial robots, which can include various devices for realizing or assisting in realizing intelligent welding, such as welding torches and line laser emitters. Because the positions of the welding torch and the line laser emitter are bound together, the viewing angle of the line laser scanning can be equivalently converted into the welding viewing angle of the welding torch, thereby realizing the determination of the welding torch's motion trajectory based on the line laser scanning trajectory of the welding process. In the industrial robot teach-free weld seam positioning system, vision devices for image acquisition, laser recognition, and other functions can also be set up to realize the recognition of the line laser scanning trajectory.

[0052] It should be noted that the aforementioned preset welding trajectory is the trajectory to be welded, such as a straight welding trajectory, a curved surface welding trajectory, etc., and this application embodiment does not limit this. The line laser scanning trajectory is the trajectory obtained by scanning and recording the preset welding trajectory with a line laser.

[0053] In practical applications, the preset welding trajectory can usually be obtained by coarse positioning through vision equipment. Line laser can be used to perform fine scanning on the preset welding trajectory to obtain welding trajectory feature points containing precise three-dimensional information of line excitation. These welding trajectory feature points can form a line laser scanning trajectory to characterize the welding to be performed.

[0054] It should be noted that the above-mentioned line laser tool coordinate system can be a three-dimensional Cartesian tool coordinate system established based on the position of the line laser sensor. It can be used to describe the position and orientation of the line laser sensor in space and can also serve as a reference coordinate system for other position data.

[0055] For example, the origin of the line laser tool coordinate system can be set as the optical center of the line laser emitter, the Z-axis of the line laser tool coordinate system can be set as the main emission direction of the line laser, the X-axis of the line laser tool coordinate system can be set as the length direction of the laser plane of the line laser, and the Y-axis of the laser tool coordinate system can be determined according to the right-hand rule or other methods.

[0056] In a specific implementation, the positioning device of this application scans a preset welding trajectory based on a line laser to obtain the line laser scanning trajectory of the preset welding trajectory in the line laser tool coordinate system. Since the position of the line laser emitter is bound to the position of the welding torch, the obtained line laser scanning trajectory can be converted into the initial welding torch movement trajectory during actual welding, providing a basis for weld seam positioning.

[0057] Step S20: Based on the line laser scanning trajectory, perform a conversion to determine the tool center point pose of the welding torch end trajectory in the welding torch end coordinate system;

[0058] Step S30: Determine the welding point pose of the welding torch based on the pose of the tool center point.

[0059] It should be noted that the welding torch tip coordinate system, i.e. the three-dimensional Cartesian tool coordinate system of the welding torch tip, can be a three-dimensional index coordinate system established based on the position of the welding torch tip. It can be used to determine the position and orientation of the welding torch tip in space and can also serve as a reference coordinate for other position data.

[0060] For example, the origin of the welding torch end coordinate system can be set to the welding end of the welding torch (i.e., the end of the welding torch), the Z-axis of the welding torch end coordinate system can be set to the central axis of the welding torch body, and the X-axis and Y-axis of the welding torch end coordinate system can be set based on the Z-axis, such as the direction of the welding torch wire feed tube, the direction of the welding torch tangent, etc.

[0061] It is understandable that, due to the positional binding between the line laser emitter and the welding torch, their relative positions and orientations are fixed and known. However, because the line laser emitter and the welding torch are installed in different spatial locations, the pose of the welding trajectory feature points of the line laser scanning path is inconsistent with the pose of the tool center point at the end of the welding torch. For example, the trajectory AB followed by the line laser emitter during scanning causes the welding torch end to synchronously follow the trajectory CD next to the line laser, while the actual welding requires the welding torch end to follow the scanning trajectory AB. Therefore, through preset calibration, the mutual conversion between the line laser scanning path and the welding torch end trajectory can be achieved, thereby converting the pose of the first tool center point on the line laser scanning path (i.e., the pose of the welding trajectory feature points) into the tool center point pose of the welding torch end trajectory in the welding torch end coordinate system. This welding torch end trajectory center point pose can be regarded as the welding point pose of the welding torch during actual welding, thus realizing the teach-free weld seam positioning of industrial robots, improving the automation level of the system compared to the traditional manual teaching method.

[0062] This embodiment of the application obtains the line laser scanning trajectory of the preset welding trajectory in the line laser tool coordinate system by scanning the preset welding trajectory with a line laser. Based on the line laser scanning trajectory, the tool center point pose of the welding torch end trajectory in the welding torch end coordinate system is determined. The welding point pose of the welding torch is then determined based on the tool center point pose. Since the line laser scanning trajectory obtained by scanning the preset welding trajectory with a line laser emitter is recorded, the actual welding torch end trajectory is simulated. By converting the line laser scanning trajectory into the welding torch end tool center point in the welding torch end coordinate system, a unified viewpoint is achieved during the welding process, avoiding resource consumption caused by frequent coordinate transformations during welding, and improving system efficiency and stability.

[0063] Based on the first embodiment of this application, in the second embodiment of this application, the content that is the same as or similar to that in the first embodiment described above can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 2 , Figure 2 This is a flowchart illustrating Embodiment 2 of the industrial robot weld seam positioning method for the present application.

[0064] like Figure 2 As shown in the embodiment of this application, the step of determining the welding point pose of the welding torch based on the pose of the tool center point includes:

[0065] Step S31: Determine whether the tip of the welding torch can reach the center point of the tool.

[0066] Step S32: When the end of the welding torch can reach the tool center point pose, the tool center point pose is taken as the welding point pose.

[0067] In some embodiments of this application, due to limitations in the robot's joint range of motion, posture, and scene collisions in practical applications, the welding torch tip may not reach the tool center point pose. Therefore, when determining the actual welding point pose, it can be first determined whether the welding torch tip can reach the tool center point pose. If the welding torch tip can reach the tool center point pose, the tool center point pose can be directly used as the welding point pose; if the welding torch tip cannot reach the tool center point pose, the tool center pose needs to be adjusted so that the welding tip can reach the adjusted tool center point pose.

[0068] It is understandable that the above welding point position is the position of the end of the welding torch during the welding process.

[0069] It should be noted that, in the embodiments of this application, the method for determining whether the end of the welding torch can reach the tool center point pose can be to determine whether the tool center point pose is reachable by inverse kinematics of an industrial robot.

[0070] It is understandable that robot inverse kinematics involves performing an inverse transformation based on the tool's center point pose to determine how the robot joints controlling the welding torch need to move to reach that tool's center point pose. In this embodiment, the robot inverse kinematics process is not limited and can be set according to the robot's position and environment in the actual application.

[0071] In some embodiments of this application, after the step of determining whether the tip of the welding torch can reach the tool center point pose, the method further includes:

[0072] Step S32': When the tip of the welding torch cannot reach the tool center point pose, the tool center point pose is rotated incrementally and iterated until the tip of the welding torch can reach the tool center point pose.

[0073] It should be noted that when the tip of the welding torch cannot reach the tool center point pose, the tool center point pose needs to be adjusted. In this embodiment, the tool center point pose can be adjusted using a stepwise incremental rotation iteration method. The position of the tool center point does not change after adjustment; only its posture changes.

[0074] It should be explained that the incremental rotation iteration method can be a method of adjusting the tool center point pose by performing at least one incremental rotation around an axis with a certain angle. In each iteration, the angle of rotation around the axis can be the same or different, and the axis of rotation can be any axis of the welding torch end coordinate system. The specific rotation can be determined according to the actual application, and the embodiments of this application do not impose any restrictions on this.

[0075] In some embodiments of this application, the step of incrementally rotating and iterating the tool center point pose until the welding torch tip can reach the tool center point pose includes: obtaining the Euler angles of the tool center point pose in the coordinate system of the welding torch tip; rotating the tool center point pose around an axis according to the value of the Euler angles to obtain the rotated tool center point pose; and returning to execute the step of determining whether the welding torch tip can reach the tool center point pose based on the rotated tool center point pose.

[0076] As can be understood, Euler angles are a method that uses three consecutive rotational angles about axes to describe the pose of an tool's center point in three-dimensional space: yaw (rotation about the Z-axis, denoted as Rz), pitch (rotation about the Y-axis, denoted as Ry), and roll (rotation about the X-axis, denoted as Rx). These three angles can uniquely determine the pose of a position.

[0077] For example, the angle of rotation around the axis each time can be 5 degrees, and the axis of rotation can be the X-axis of the coordinate system of the welding torch end.

[0078] For example, the angle of rotation around the axis each time can be 3 degrees, and the axis of rotation can be the Y-axis of the coordinate system of the welding torch end.

[0079] For example, the angle of rotation around the axis can be determined based on the positional relationship between the maximum reachable pose of the welding torch tip and the pose of the tool center point. For instance, the initial angle of rotation around the axis is a first angle, which can be used as the rotation angle for the first iteration. If the welding torch tip still cannot reach the target after rotation, the first angle is attenuated by an attenuation value to obtain a second angle, and this second angle is used as the rotation angle to continue iterating until the welding torch tip reaches the target.

[0080] For example, a minimum decay angle can be set so that the rotation angle decays within the range of the first angle and the minimum angle. When the rotation angle decays to the minimum angle, it stops decaying, and subsequent iterations use the minimum angle as the rotation angle for each iteration.

[0081] For example, the initial rotation angle can be 8 degrees, the minimum angle can be 3 degrees, and the decay value can be 1 degree. In the first iteration, the tool center point is rotated around the X-axis of the welding torch end coordinate system using 8 degrees as the rotation angle to obtain the tool center point after the iteration. If the tool center point pose after the iteration is still unreachable from the welding torch end, then 7 degrees can be used as the rotation angle to rotate the tool center point pose around the X-axis of the welding torch end coordinate system. If the welding torch end is still unreachable when the rotation angle decays to 3 degrees, then the decay will not continue, and 3 degrees will be fixed as the rotation angle for subsequent iterations until the welding torch end can reach the tool center point pose after the iteration.

[0082] In this embodiment, the direction of rotation about an axis can be determined based on the value of the Euler angles. Specifically, the step of rotating the tool center point pose about an axis based on the value of the Euler angles to obtain a rotated tool center point pose includes: when the value of the Euler angles is positive, rotating the tool center point pose counterclockwise about an axis to obtain a rotated tool center point pose; or, when the value of the Euler angles is negative, rotating the tool center point pose clockwise about an axis to obtain a rotated tool center point pose.

[0083] Understandably, by using the incremental rotation iteration method, the pose of the unreachable tool center point can be quickly converged to the reachable point, avoiding system failures caused by the unreachability of the tool center point pose. Compared with the commonly used binary search method, this improves computational efficiency.

[0084] This application embodiment determines whether the welding torch tip can reach the tool center point pose. When the welding torch tip can reach the tool center point pose, the tool center point pose is used as the welding point pose. When the welding torch tip cannot reach the tool center point pose, the tool center point pose is iteratively rotated incrementally until the welding torch tip can reach the tool center point pose. Because the adjustment is made through an iterative incremental rotation method when the welding torch tip cannot reach the tool center point pose, the achievable pose of the welding torch can be quickly calculated, improving the adaptability of the industrial robot teach-and-write weld seam finding system to the welding environment.

[0085] Based on the first and / or second embodiments of this application, in the third embodiment of this application, the content that is the same as or similar to the first and / or second embodiments described above can be referred to the above description and will not be repeated hereafter. Based on this, please refer to... Figure 3 , Figure 3 This is a flowchart illustrating Embodiment 3 of the industrial robot weld seam positioning method for the present application.

[0086] like Figure 3 As shown in the embodiment of this application, the step of determining the tool center point pose of the welding torch end trajectory in the welding torch end coordinate system based on the transformation of the line laser scanning trajectory includes:

[0087] Step S11: Obtain the pre-built spatial transformation model;

[0088] Step S12: Based on the spatial transformation model, the scanning point pose of the line laser scanning trajectory is transformed to obtain the tool center point pose of the welding torch end trajectory in the welding torch end coordinate system.

[0089] It should be noted that the pre-constructed spatial transformation model described above is based on the positions of the industrial robot flange, the welding torch tip, and the line laser emitter. The spatial transformation model can characterize the positional relationships between the industrial robot flange, the welding torch tip, and the line laser emitter. Through the spatial transformation model, mutual transformation of position coordinates in each tool coordinate system can be achieved.

[0090] In some embodiments of this application, spatial modeling can be performed first to achieve coordinate transformation. Specifically, based on the characteristics of the welding environment, the welding end coordinate system T0 and the line laser tool coordinate system T1 can be calibrated respectively. At the same time, three rotation matrices can be established between the welding end coordinate system, the line laser tool coordinate system, and the robot flange tool coordinate system. These rotation matrices can serve as a spatial transformation model for realizing the coordinate positions between the tool coordinate systems.

[0091] Understandably, the pose of the robot flange in the base coordinate system can be calculated based on the defined line laser tool coordinate system (the line laser tool coordinate system and the robot flange tool coordinate system are a fixed transformation). Then, by combining the relative transformation between the welding torch end coordinate system and the robot flange, the welding torch end trajectory and the tool center point pose in the welding torch end coordinate system can be obtained.

[0092] For example, the transformation matrix between the line laser tool coordinate system and the base coordinate system can be shown in equation (1) below:

[0093] (1);

[0094] in, This represents the pose of the line laser tool coordinate system relative to the base coordinate system. This represents the pose of the welding trajectory feature point P relative to the base coordinate system, as scanned by the line laser emitter. This indicates the pose deflection of the actual tool center point at the end of the welding torch relative to the feature points of the welding trajectory.

[0095] For example, the transformation matrix between the robot flange tool coordinate system and the base coordinate system can be shown in equation (2) below:

[0096] (2);

[0097] in, This represents the pose of the robot flange relative to the base coordinate system. This indicates the offset of the line laser tool coordinate system relative to the robot flange.

[0098] For example, the transformation matrix between the coordinate system at the weld end and the base coordinate system can be represented by the following equation (3):

[0099] (3);

[0100] in, This indicates the pose of the weld end coordinate system relative to the base coordinate system. This represents the pose of the robot flange relative to the base coordinate system. This indicates the offset of the tool coordinate system at the weld end relative to the robot flange.

[0101] It is understandable that, based on the combined calculation of the above equations (1), (2), and (3), the tool center point pose at the end of the welding torch during line laser scanning (such as the pose of the point on the above straight trajectory CD) can be used to obtain the tool center point pose at the end of the welding torch in the coordinate system at the end of the welding torch during actual welding, that is, the pose point that the end of the welding torch needs to reach in actual welding.

[0102] It should be noted that the above-mentioned base coordinate system can be a coordinate system established based on the base of the industrial robot.

[0103] This application embodiment obtains a pre-constructed spatial transformation model; based on the spatial transformation model, the scanning point pose of the line laser scanning trajectory is transformed to obtain the tool center point pose of the welding torch end trajectory in the welding torch end coordinate system. Since a unified tool coordinate system control is achieved through pre-calibrated spatial transformation model, frequent coordinate transformations between welding commands and scanning commands are avoided, thereby simplifying the system control process and improving welding accuracy and work efficiency.

[0104] It should be noted that the above examples are only for understanding this application and do not constitute a limitation on the teaching-free weld seam positioning method for industrial robots in this application. Any simple modifications based on this technical concept are within the protection scope of this application.

[0105] This application also provides a teach-free weld seam positioning device for industrial robots. Please refer to [link / reference]. Figure 4 , Figure 4 This is a schematic diagram of the module structure of the industrial robot no-teach weld seam positioning device according to an embodiment of this application. The industrial robot no-teach weld seam positioning device includes:

[0106] The trajectory scanning module 10 is used to scan a preset welding trajectory based on the line laser to obtain the line laser scanning trajectory of the preset welding trajectory in the line laser tool coordinate system;

[0107] The trajectory conversion module 20 is used to convert the trajectory based on the line laser scanning trajectory and determine the tool center point pose of the welding gun end trajectory in the welding gun end coordinate system.

[0108] The positioning module 30 is used to determine the welding point orientation of the welding torch based on the orientation of the tool center point.

[0109] The industrial robot teach-free weld seam positioning device provided in this application, employing the industrial robot teach-free weld seam positioning method in the above embodiments, can solve the technical problem that existing line laser welding requires frequent coordinate system transformations between welding commands and scanning commands, increasing the workload of programming and debugging. Compared with the prior art, the beneficial effects of the industrial robot teach-free weld seam positioning device provided in this application are the same as those of the industrial robot teach-free weld seam positioning method provided in the above embodiments, and other technical features in the industrial robot teach-free weld seam positioning device are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0110] This application provides an industrial robot teach-free weld seam positioning device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, which are executed by the at least one processor to enable the at least one processor to perform the industrial robot teach-free weld seam positioning method in the first embodiment described above.

[0111] The following is for reference. Figure 5 The diagram illustrates a structural schematic suitable for implementing an industrial robot no-teach weld seam positioning device according to embodiments of this application. The industrial robot no-teach weld seam positioning device in embodiments of this application may include, but is not limited to, mobile terminals such as mobile phones, laptops, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Description), PMPs (Portable Media Players), and vehicle terminals (e.g., vehicle navigation terminals), as well as fixed terminals such as digital TVs and desktop computers. Figure 5 The industrial robot teach-free weld seam positioning device shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.

[0112] like Figure 5As shown, the industrial robot teach-free weld seam locating device may include a processing unit 1001 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes according to a program stored in read-only memory (ROM) 1002 or a program loaded from storage device 1003 into random access memory (RAM) 1004. The RAM 1004 also stores various programs and data required for the operation of the industrial robot teach-free weld seam locating device. The processing unit 1001, ROM 1002, and RAM 1004 are interconnected via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to I / O interface 1006: input devices 1007 including, for example, touchscreens, touchpads, keyboards, mice, image sensors, microphones, accelerometers, gyroscopes, etc.; output devices 1008 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 1003 including, for example, magnetic tapes, hard disks, etc.; and communication devices 1009. Communication device 1009 allows the industrial robot no-teach weld seam finding device to exchange data wirelessly or via wired communication with other devices. Although the figure shows industrial robot no-teach weld seam finding devices with various systems, it should be understood that it is not required to implement or possess all the systems shown. More or fewer systems can be implemented alternatively.

[0113] Specifically, according to the embodiments disclosed in this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from ROM 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this application.

[0114] The industrial robot teach-free weld seam positioning device provided in this application, employing the industrial robot teach-free weld seam positioning method in the above embodiments, can solve the technical problem that existing line-to-line laser welding requires frequent coordinate system transformations between welding commands and scanning commands, increasing the workload of programming and debugging. Compared with the prior art, the beneficial effects of the industrial robot teach-free weld seam positioning device provided in this application are the same as those of the industrial robot teach-free weld seam positioning method provided in the above embodiments, and other technical features in this industrial robot teach-free weld seam positioning device are the same as those disclosed in the previous embodiment method, and will not be repeated here.

[0115] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0116] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0117] This application provides a computer-readable storage medium having computer-readable program instructions (i.e., a computer program) stored thereon, the computer-readable program instructions being used to execute the industrial robot teachless weld seam positioning method in the above embodiments.

[0118] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), or flash memory, optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0119] The aforementioned computer-readable storage medium may be included in the industrial robot teach-free weld seam positioning device; or it may exist independently and not be assembled into the industrial robot teach-free weld seam positioning device.

[0120] The aforementioned computer-readable storage medium carries one or more programs that, when executed by the industrial robot's teachless weld seam positioning device, cause the industrial robot's teachless weld seam positioning device to:

[0121] Based on the line laser, a preset welding trajectory is scanned to obtain the line laser scanning trajectory of the preset welding trajectory in the line laser tool coordinate system;

[0122] Based on the line laser scanning trajectory, the tool center point pose of the welding gun end trajectory in the welding gun end coordinate system is determined by conversion.

[0123] The welding point orientation of the welding torch is determined based on the orientation of the tool's center point.

[0124] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0125] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0126] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.

[0127] The readable storage medium provided in this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., a computer program) for executing the above-described industrial robot teach-free weld seam positioning method. This solves the technical problem that existing line-to-line laser welding requires frequent coordinate system transformations between welding and scanning instructions, increasing the workload of programming and debugging. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in this application are the same as those of the industrial robot teach-free weld seam positioning method provided in the above embodiments, and will not be repeated here.

[0128] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the above-described industrial robot teach-free weld seam positioning method.

[0129] The computer program product provided in this application can solve the technical problem that existing line-to-line laser welding requires frequent coordinate system transformations between welding commands and scanning commands, increasing the workload of programming and debugging. Compared with the prior art, the beneficial effects of the computer program product provided in this application are the same as those of the industrial robot teach-free weld seam positioning method provided in the above embodiments, and will not be repeated here.

[0130] The above description is only a part of the embodiments of this application and does not limit the scope of protection of this application. All equivalent structural transformations made under the technical concept of this application and using the content of this application specification and drawings, or direct / indirect applications in other related technical fields, are included in the scope of protection of this application.

Claims

1. A method for teaching-free weld seam positioning in industrial robots, characterized in that, The method is applied to an industrial robot teach-free weld seam positioning system, the system comprising: a welding torch and a line laser emitter; the line laser emitter is positioned and bound to the welding torch for emitting a line laser; the method comprises: Based on the line laser, a preset welding trajectory is scanned to obtain the line laser scanning trajectory of the preset welding trajectory in the line laser tool coordinate system; Based on the line laser scanning trajectory, the tool center point pose of the welding gun end trajectory in the welding gun end coordinate system is determined by conversion. The welding point pose of the welding torch is determined based on the pose of the tool's center point. The step of determining the tool center point pose of the welding torch end trajectory in the welding torch end coordinate system by transforming the line laser scanning trajectory includes: Obtain a pre-constructed spatial transformation model; the spatial transformation model includes: the transformation matrix between the line laser tool coordinate system and the base coordinate system, the transformation matrix between the robot flange tool coordinate system and the base coordinate system, and the transformation matrix between the weld end coordinate system and the base coordinate system; Based on the spatial transformation model, the pose of the scanning point of the line laser scanning trajectory is transformed to obtain the pose of the tool center point of the welding gun end trajectory in the welding gun end coordinate system. The transformation matrix between the line laser tool coordinate system and the base coordinate system is: ； in, This represents the pose of the line laser tool coordinate system relative to the base coordinate system. This represents the pose of the welding trajectory feature point P relative to the base coordinate system, as scanned by the line laser emitter. This indicates the pose deflection of the actual tool center point at the end of the welding torch relative to the feature points of the welding trajectory. The transformation matrix between the coordinate system at the weld end and the base coordinate system is: ； in, This indicates the pose of the weld end coordinate system relative to the base coordinate system. This represents the pose of the robot flange relative to the base coordinate system. This indicates the offset of the tool coordinate system at the weld end relative to the robot flange.

2. The industrial robot teach-free weld seam positioning method as described in claim 1, characterized in that, The step of determining the welding point pose of the welding torch based on the pose of the tool center point includes: Determine whether the tip of the welding torch can reach the center point of the tool. When the tip of the welding torch can reach the center point of the tool, the center point of the tool is taken as the welding point.

3. The industrial robot teach-free weld seam positioning method as described in claim 2, characterized in that, After the step of determining whether the tip of the welding torch can reach the center point pose of the tool, the method further includes: When the tip of the welding torch cannot reach the tool center point pose, the tool center point pose is rotated incrementally and iterated until the tip of the welding torch can reach the tool center point pose.

4. The industrial robot teach-free weld seam positioning method as described in claim 3, characterized in that, The step of incrementally rotating and iterating the tool center point pose until the welding torch tip can reach the tool center point pose includes: Obtain the Euler angles of the tool center point pose in the coordinate system of the welding torch end; The tool center point pose is rotated around the axis according to the Euler angle value to obtain the rotated tool center point pose, and the step of determining whether the welding gun tip can reach the tool center point pose is returned based on the rotated tool center point pose.

5. The industrial robot teach-free weld seam positioning method as described in claim 4, characterized in that, The step of rotating the tool center point pose about an axis based on the Euler angle values ​​to obtain the rotated tool center point pose includes: When the value of the Euler angle is positive, the tool center point pose is rotated counterclockwise around the axis to obtain the rotated tool center point pose; Alternatively, when the Euler angle is negative, the tool center point pose is rotated clockwise around the axis to obtain the rotated tool center point pose.

6. A teach-free weld seam positioning device for industrial robots, characterized in that, The industrial robot is used to implement the industrial robot teach-free weld seam positioning method as described in any one of claims 1-5, and the apparatus includes: The trajectory scanning module is used to scan a preset welding trajectory based on the line laser to obtain the line laser scanning trajectory of the preset welding trajectory in the line laser tool coordinate system; The trajectory conversion module is used to convert the line laser scanning trajectory and determine the tool center point pose of the welding gun end trajectory in the welding gun end coordinate system. The positioning module is used to determine the welding point orientation of the welding torch based on the orientation of the tool's center point. The trajectory transformation module is also used to acquire a pre-constructed spatial transformation model; the spatial transformation model includes: a transformation matrix between the line laser tool coordinate system and the base coordinate system, a transformation matrix between the robot flange tool coordinate system and the base coordinate system, and a transformation matrix between the weld end coordinate system and the base coordinate system; based on the spatial transformation model, the scanning point pose of the line laser scanning trajectory is transformed to obtain the tool center point pose of the welding torch end trajectory in the welding torch end coordinate system; The transformation matrix between the line laser tool coordinate system and the base coordinate system is: ； in, This represents the pose of the line laser tool coordinate system relative to the base coordinate system. This represents the pose of the welding trajectory feature point P relative to the base coordinate system, as scanned by the line laser emitter. This indicates the pose deflection of the actual tool center point at the end of the welding torch relative to the feature points of the welding trajectory. The transformation matrix between the coordinate system at the weld end and the base coordinate system is: ； in, This indicates the pose of the weld end coordinate system relative to the base coordinate system. This represents the pose of the robot flange relative to the base coordinate system. This indicates the offset of the tool coordinate system at the weld end relative to the robot flange.

7. A teach-free weld seam positioning device for industrial robots, characterized in that, The device includes: a memory, a processor, and an industrial robot teach-free weld seam location program stored in the memory and executable on the processor, the industrial robot teach-free weld seam location program being configured to implement the steps of the industrial robot teach-free weld seam location method as described in any one of claims 1 to 5.

8. A storage medium, characterized in that, The storage medium stores an industrial robot no-teach weld seam positioning program, which, when executed by a processor, implements the steps of the industrial robot no-teach weld seam positioning method as described in any one of claims 1 to 5.

9. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the steps of the industrial robot teach-free weld seam positioning method as described in any one of claims 1 to 5.

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