Three-dimensional curved surface welding robot welding process posture real-time adjusting method and system

Abstract

The application relates to a real-time adjusting method and system for a posture of a three-dimensional curved surface welding robot welding process, and the real-time adjusting method comprises the following steps: calibrating relative position relationship matrices of components of a robot welding system and establishing a base coordinate system O W of a robot base, a terminal actuator coordinate system O t of a welding torch and a camera coordinate system O C of a visual sensor; defining a, b and c values of Euler angles to represent a deflection angle, a pitch angle and a rotation angle of the welding torch; initializing the welding torch according to a direction vector containing the Euler angles; calculating the a, b and c values of the Euler angles when the welding torch is fitted to a welding seam according to an indication vector in the base coordinate system; and adjusting the posture of the welding torch according to the calculated Euler angles; the application can adapt to complex three-dimensional curved surface welding seams, can correct the posture of the welding torch in real time, can make the welding torch fitted to the welding seam, can meet welding requirements and can improve welding quality.

Description

Technical Field

[0001] This invention relates to the field of welding robot technology, and in particular to a method and system for real-time posture adjustment during the welding process of a three-dimensional curved surface weld robot. Background Technology

[0002] With the strategic transformation of my country's manufacturing industry, my country's industrial robot technology has developed rapidly. Welding robots have also played an important role in welding operations. They mainly perform automated and intelligent welding on components assembled in the previous process. Compared with manual welding, welding robots have higher stability and higher quality assurance, and can significantly improve production efficiency.

[0003] Currently, welding robots primarily operate using a "teach-and-reproduce" method. This involves manually recording the welding path and actions at different points using a teach pendant before welding begins. The welding robot then uses this data to perform the welding operation. While this method allows for position and orientation teaching based on weld characteristics, the teaching process is cumbersome, and its accuracy heavily relies on the operator's skill and condition, making it difficult to obtain stable and accurate teaching results and impacting welding quality stability.

[0004] In numerous studies on welding position adjustment, existing technologies use sensors to detect weld coordinates to adjust the welding torch position in real time during the welding process, thus partially solving the problem of cumbersome manual teaching. However, this method only supports the adjustment of the welding torch position. As the complexity of three-dimensional curved surface welds increases, it cannot adjust the welding torch posture according to the undulations and turns of the weld, making it difficult to adapt to the welding requirements of three-dimensional curved surface welds and affecting welding quality. Summary of the Invention

[0005] To address the shortcomings of related technologies, this invention provides a real-time posture adjustment method for a three-dimensional curved surface weld robot during the welding process. Euler angles are introduced to adjust the deflection, pitch, and rotation angles of the welding torch, thereby correcting the posture and position of the welding torch in real time so that it fits the weld seam, adapting to highly complex three-dimensional curved surface weld seams and meeting complex welding requirements.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for real-time posture adjustment during the welding process of a three-dimensional curved surface weld robot is disclosed for use in a robot welding system. The robot welding system includes: a robot base, a welding torch connected to the robot base, and a vision sensor disposed at the welding torch. The real-time adjustment method includes:

[0008] A matrix representing the relative positions of the components of the robot welding system is calibrated, and a spatial coordinate system is established. This spatial coordinate system includes: the base coordinate system O where the robot base is located. W The coordinate system O of the end effector where the welding torch is located t The camera coordinate system O where the visual sensor is located C ;

[0009] Define Euler angles for the robot welding process in the end effector coordinate system O. t An internal direction vector containing Euler angles is established and projected onto the base coordinate system through the camera coordinate system, thus converting it into an indicator vector. The Euler angles include values ​​a, b, and c. The value a of the Euler angles is defined as the deflection angle of the welding torch, the value b of the Euler angles is defined as the pitch angle of the welding torch, and the value c of the Euler angles is defined as the rotation angle of the welding torch.

[0010] Initialize the welding torch attitude and position based on the direction vector containing Euler angles;

[0011] The vision sensor acquires weld seam information and calculates the values ​​of Euler angles a, b, and c when the welding torch is in contact with the weld seam based on the indicated vector.

[0012] Adjust the welding torch posture according to the Euler angles a, b, and c values ​​when the welding torch is in contact with the weld.

[0013] In some embodiments of the present invention, calibrating the relative positional relationship matrix of the components of the robotic welding system includes:

[0014] Obtain the base coordinate system O W Coordinate system O of the robot end effector t Spatial transformation matrix between w T t ;

[0015] Obtain the coordinate system O of the robot end effector t and the camera coordinate system O C Spatial transformation matrix between t T C ;

[0016] Establish a base coordinate system O W With respect to the camera coordinate system O C Positional relationship representation: P W = w T t t T C P C , where P W Base coordinate system O W At a certain point in the middle, P C Camera coordinate system OC A certain point in the middle.

[0017] In some embodiments of the present invention, Euler angles are defined for the robot welding process, in the end effector coordinate system O. t Establish a direction vector containing Euler angles and project it onto the base coordinate system O. W The following is converted into an indicator vector, including:

[0018] In the robot end effector coordinate system O t Within, generate direction vectors emanating from the origin that coincide with the X, Y, and Z axes, respectively. Where the X-axis represents the forward direction of the welding torch, the Y-axis represents the horizontal direction of the welding torch, and the Z-axis represents the vertical direction of the welding torch; that is, the direction vector in the XY plane. The angle between the direction and the X-axis is the Euler angle α; the direction vector in the XZ plane. The angle between the Z-axis and the Z-axis is the Euler angle b; the direction vector in the YZ plane. The angle between the Y-axis and the Y-axis is the value of Euler angle c;

[0019] The direction vectors are all transformed by the space transformation matrix. w T t The base coordinate system O is obtained W The following indicator vectors include: deflection indicator vector Pitch indicator vector Rotation indicator vector

[0020] In some embodiments of the present invention, initializing the welding torch position according to the direction vector containing Euler angles includes:

[0021] According to the base coordinate system O W With respect to the camera coordinate system O C The positional relationship is used to obtain the initial distance of the weld in the base coordinate system O. W A series of coordinate points are obtained and projected onto the base coordinate system O. W By examining the XY and XZ planes, a series of two-dimensional coordinate points within the corresponding planes can be obtained;

[0022] Based on a series of two-dimensional coordinate points in the corresponding plane, the initial distance of the weld in the base coordinate system O is obtained through least squares fitting. W Fitted lines in the inner XY plane and XZ plane;

[0023] Move the welding torch to position it in the base coordinate system O. W The projection points of the XY and XZ planes are located at the midpoints of the fitted lines of the corresponding planes to complete the initialization of the welding gun position.

[0024] In some embodiments of the present invention, initializing the welding torch posture according to the direction vector containing Euler angles includes:

[0025] Control the welding torch posture in the robot end effector coordinate system O t Within this process, the Euler angles a, b, and c are all set to 0 to initialize the welding torch posture.

[0026] In some embodiments of the present invention, obtaining weld information and calculating the values ​​of Euler angles a and b when the welding torch is in contact with the weld based on the indicator vector includes:

[0027] According to the base coordinate system O W With respect to the camera coordinate system O C Based on the positional relationship, the welding distance of the weld in the next time period is obtained in the base coordinate system O. W A series of coordinate points are obtained and projected onto the base coordinate system O. W The XY and XZ planes are used to obtain a series of two-dimensional coordinate points in the corresponding planes;

[0028] Based on a series of two-dimensional coordinate points in the corresponding plane, the welding distance of the weld in the next time period in the base coordinate system O is obtained by least squares fitting. W Multiple fitted lines in the XY plane and multiple fitted lines in the XZ plane;

[0029] In the corresponding plane, multiple fitted straight lines are refitted into a continuous weld curve equation using a smooth transition algorithm, including: Y XY =f XY (X), X XZ =f XZ (Z); where Y XY Base coordinate system O W The weld curve fitted in the lower XY plane, f XY (X) is its weld curve equation; X XZ Let O be the base coordinate system W The weld curve fitted in the lower XZ plane, f XZ (Z) is its weld curve equation;

[0030] According to the deflection indicator vector With the weld curve equation Y XY =f XY (X) is used to calculate the value of Euler angle α when the welding torch is in contact with the weld seam based on the preset geometric relationship.

[0031] According to the pitch indicator vector With the weld curve equation X XZ =f XZ(Z) The pre-defined geometric relationship is used to calculate the value of the Euler angle b when the welding torch is in contact with the weld.

[0032] In some embodiments of the present invention, calculating the value of the Euler angle c when the welding torch is in contact with the weld seam based on the indicated vector includes:

[0033] According to the base coordinate system O W With respect to the camera coordinate system O C The positional relationship is used to obtain the weld point and the weldment points on both sides of the weld at the current moment in the base coordinate system O. W A series of coordinate points are obtained and projected onto the base coordinate system O. W The YZ plane is used to obtain a series of two-dimensional coordinate points within the YZ plane;

[0034] Based on a series of two-dimensional coordinate points in the YZ plane, the inclined straight line Z of the weldment surface is obtained through least squares fitting. YZ =f YZ (Y); where Z YZ Base coordinate system O W The inclined straight line of the weldment surface fitted in the lower YZ plane, f YZ (Y) is the equation of the straight line with the inclined surface of the weldment;

[0035] According to the gyration indicator vector The weldment surface is inclined along a straight line Z. YZ =f YZ (Y) is the preset geometric relationship, and the value of c of Euler angle is calculated when the welding torch is attached to the weld.

[0036] In some embodiments of the present invention, the preset geometric relationship between each of the indicator vectors and the weld curve equation includes:

[0037] In the base coordinate system O W In the XY plane below, the deflection indicator vector Equation of weld curve Y in the XY plane XY =f XY The direction vector of the tangent line to (X) is parallel;

[0038] In the base coordinate system O W In the XZ plane below, the pitch indication vector Equation of weld curve with respect to the XZ plane X XZ =f XZ The direction vector of the normal to (Z) is parallel;

[0039] In the base coordinate system O W In the YZ plane below, the rotation indicator vector The weldment surface is inclined along a straight line Z. YZThe direction vector of the normal to fYZ(Y) is parallel.

[0040] In some embodiments of the present invention, calculating the Euler angles a, b, and c when the welding torch is in contact with the weld seam includes:

[0041] According to the base coordinate system O W With respect to the camera coordinate system O C Based on the positional relationship, obtain the coordinates of the welding point at the next welding moment of the weld in the base coordinate system, and project it onto the base coordinate system O. W The XY, XZ, and YZ planes are used to obtain the base coordinate system O. W Let the coordinates of point A(x0, y0), point B(z0, x0), and point C(y0, z0) be the coordinates of the points A, B, and C respectively.

[0042] Then the weld curve equation Y XY =f XY The equation of the tangent line to (X) at point A is: y - y0 = f′(x0)(x - x0), and one direction vector of the tangent line equation is:

[0043] The weld curve equation f XZ =f XZ The equation of the normal line (Z) at point B is: One direction vector of its normal equation is:

[0044] The surface of the weldment is inclined by a straight line Z. YZ =f YZ The equation of the normal line (Y) at point C is: One direction vector of its normal equation is:

[0045] The spatial transformation matrix is ​​obtained as follows:

[0046] Calculate the deflection indicator vector

[0047] Calculate the pitch indicator vector

[0048] Calculate the slewing indicator vector

[0049] Where θ1 is the value of Euler angle a, θ2 is the value of Euler angle b, and θ3 is the value of Euler angle c; m, n, u, and v correspond to the spatial transformation relationship between the robot base and the welding torch, and are all preset values; f′(x0) is the curve equation f XY (X) is the derivative of f at coordinate point A; f′(z0) is the equation of the curve fXZ (Z) is the derivative at coordinate point B; f′(y0) is the equation of the curve f YZ (Y) is the derivative of the coordinate point C;

[0050] The value of α for the Euler angle when the welding torch is in contact with the weld is calculated as follows:

[0051]

[0052] The value of 'b' for the Euler angle when the welding torch is in contact with the weld is calculated as follows:

[0053]

[0054] The value of c for the Euler angle when the welding torch is in contact with the weld is calculated as follows:

[0055]

[0056] In addition, the present invention also provides a three-dimensional curved surface weld seam robot system, which is applied to the real-time posture adjustment method of the three-dimensional curved surface weld seam robot during the welding process.

[0057] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0058] 1. This invention collects data through a vision sensor and introduces Euler angles to adjust the deflection, pitch, and rotation angles of the welding torch, thereby correcting the welding torch posture in real time to make it fit the weld seam, adapting to highly difficult three-dimensional curved surface weld seams, meeting complex welding requirements, and improving the quality of the welding process.

[0059] 2. Compared with the traditional "teach-reproduce" method, this invention reduces the dependence on manual labor and reduces labor costs. It only uses vision sensors and controllers for adjustment, omitting the tedious robot welding teaching process and improving welding efficiency.

[0060] 3. This invention is based on data collected by a vision sensor and the computer automatically calculates the Euler angles to be adjusted and transmits them to the controller for adjustment. Compared with the traditional welding process, it has higher adjustment accuracy and avoids errors caused by manual operation. Attached Figure Description

[0061] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0062] Figure 1 This is a flowchart illustrating real-time attitude adjustment according to an embodiment of the present invention.

[0063] Figure 2 This is a schematic diagram of a robotic welding system according to an embodiment of the present invention;

[0064] Figure 3a A three-dimensional view of a workpiece with a complex weld seam on a three-dimensional curved surface;

[0065] Figure 3b A top view of a workpiece with a complex three-dimensional curved weld.

[0066] Figure 3c A side view of a workpiece with a complex three-dimensional curved weld.

[0067] Figure 3d A front view of a workpiece with a complex three-dimensional curved surface weld.

[0068] Figure 4 In one embodiment of the present invention, the coordinate system O of the robot end effector is shown. t A schematic diagram of the α value of the Euler angles in the XY plane;

[0069] Figure 5 This is a schematic diagram illustrating the relationship between the deflection indicator vector and the welding torch deflection attitude according to an embodiment of the present invention;

[0070] Figure 6 This is a schematic diagram illustrating the effect of adjusting the welding torch deflection angle according to one embodiment of the present invention;

[0071] Figure 7 In one embodiment of the present invention, the coordinate system O of the robot end effector is shown. t A schematic diagram of the b-values ​​of the Euler angles in the XZ plane;

[0072] Figure 8 This is a schematic diagram illustrating the relationship between the pitch indicator vector and the pitch attitude of the welding torch according to an embodiment of the present invention;

[0073] Figure 9 This is a schematic diagram illustrating the effect of adjusting the welding torch pitch angle according to one embodiment of the present invention;

[0074] Figure 10 In one embodiment of the present invention, the coordinate system O of the robot end effector is shown. t A schematic diagram of the c-values ​​of the Euler angles in the YZ plane;

[0075] Figure 11 This is a schematic diagram illustrating the relationship between the rotation indicator vector and the welding torch rotation posture according to an embodiment of the present invention;

[0076] Figure 12 This is a schematic diagram illustrating the effect of adjusting the welding torch rotation angle according to one embodiment of the present invention;

[0077] In the above figures: 1. Industrial robot; 2. Welding torch; 3. Vision sensor; 4. Detection range of vision sensor; 5. Weld seam; 6. Welded part; 11. Initial deflection posture of welding torch; 13. Target deflection posture of welding torch in the XY plane of the base coordinate system; 16. Deflection posture of welding torch after adjustment in one embodiment; 17. Deflection posture of welding torch without adjustment in one embodiment; 21. Initial pitch posture of welding torch; 22. Target pitch posture of welding torch in the XZ plane of the base coordinate system; 25. Pitch posture of welding torch without adjustment in one embodiment; 26. Pitch posture of welding torch after adjustment in one embodiment; 30. Initial rotation posture of welding torch; 32. Target rotation posture of welding torch in the YZ plane of the base coordinate system; 33. Tilt curve of welded part surface; 35. Rotation posture of welding torch after adjustment in one embodiment; 36. Rotation posture of welding torch without adjustment in one embodiment. Detailed Implementation

[0078] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0079] In the description of this invention, it should be understood that the terms "center", "lateral", "longitudinal", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0080] The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include one or more of that feature.

[0081] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0082] As attached Figure 1 and attached Figure 2 As shown, in an illustrative embodiment of a method for real-time attitude adjustment during the welding process of a three-dimensional curved surface weld robot according to the present invention, the robot welding system includes:

[0083] The robot base is located at the bottom of industrial robot 1;

[0084] Welding torch 2 is connected to the robot base and is located at the end of industrial robot 1;

[0085] A vision sensor 3 is located at the front end of the welding torch 2;

[0086] The controller is used to control the attitude and position of welding torch 2;

[0087] A calculator used to process coordinate information transformations in different coordinate systems;

[0088] The welding torch 2 and the vision sensor 3 are fixed on the flange of the robot. The vision sensor 3 is mainly composed of a line laser generator and an industrial camera. Using the principle of optical triangulation, the industrial camera collects the stripe feature information of the laser projected onto the surface of the weldment. The pixel coordinates of the laser stripe feature points are obtained through image processing. Then, through coordinate transformation, the three-dimensional spatial coordinate information of the weld seam points on the surface of the weldment can be obtained.

[0089] A method for real-time posture adjustment during the welding process of a three-dimensional curved surface weld robot includes:

[0090] The relative positional relationship matrix of each component of the robot welding system is calibrated and a spatial coordinate system is established. The spatial coordinate system includes: the base coordinate system O where the robot base is located. W The coordinate system O of the end effector where welding torch 2 is located t The camera coordinate system O where the visual sensor 3 is located C ;

[0091] Define Euler angles for the robot welding process in the end effector coordinate system O. t An internal direction vector containing Euler angles is established and projected onto the base coordinate system through the camera coordinate system, thus converting it into an indicator vector. The Euler angles include values ​​a, b, and c. The value a of the Euler angle is defined as the deflection angle of the welding torch, the value b of the Euler angle is defined as the pitch angle of the welding torch, and the value c of the Euler angle is defined as the rotation angle of the welding torch.

[0092] Initialize the welding torch attitude and position based on the direction vector containing Euler angles;

[0093] The vision sensor acquires weld seam information and calculates the a, b, and c values ​​of the Euler angles when the welding torch is in contact with the weld seam based on the indication vector;

[0094] Adjust the welding torch posture according to the Euler angles a, b, and c values ​​when the welding torch 2 is in contact with the weld.

[0095] Among them, as attached Figure 2 As shown, the workpiece 6 has a three-dimensional curved weld seam 5. During the welding process, the weld seam 5 first passes through the detection range 4 of the vision sensor 3, and the welding torch 2 passes behind the vision sensor 3 to weld the weld seam 5. The vision sensor 3 collects the spatial coordinate information of the weld seam 5 in advance, which is used to initialize the welding torch and adjust the position and posture of the welding torch 2 at any time to ensure the accuracy of the welding position and the welding quality.

[0096] Specifically, in order to better describe the positional information of weld feature points in space, three coordinate systems are introduced, namely the base coordinate system O where the industrial robot 1 base is located. W The robot end effector coordinate system O where welding torch 2 is located t The camera coordinate system O where the visual sensor 3 is located c In the end effector coordinate system O t The system defines Euler angle 'a' to represent the deflection angle of the welding torch, displaying its deflection attitude; Euler angle 'b' to represent the pitch angle, displaying its pitch attitude; and Euler angle 'c' to represent the slewing angle, displaying its slewing attitude. By calculating the Euler angles 'a', 'b', and 'c' when the welding torch is in contact with the weld seam, and transmitting these values ​​to the controller, the system adjusts the welding torch attitude to adapt to complex welding conditions, achieving real-time adjustment of the welding torch attitude.

[0097] In some embodiments of the present invention, calibrating the relative positional relationship matrix of the components of the robotic welding system includes:

[0098] Obtain the base coordinate system O W With respect to the robot end effector coordinate system O t Spatial transformation matrix between w T t ;

[0099] Obtain the coordinate system O of the robot end effector t and camera coordinate system O C Spatial transformation matrix between t T C ;

[0100] Establish a base coordinate system O W With camera coordinate system O C Positional relationship representation: P W = w T t t T C P C , where P W Base coordinate system O W At a certain point in the middle, PC Camera coordinate system O C A certain point in the middle.

[0101] Since the welding torch 2 and the vision sensor 3 are fixed to the robot's flange, the robot's end effector coordinate system O where the welding torch 2 is located... t and the camera coordinate system O where the visual sensor 3 is located c The spatial transformation relationship between them is fixed, using the spatial transformation matrix. t T c This is represented by the base coordinate system O. W The coordinate system O of the robot end effector where the welding torch is located t The transformation relationship between them can be obtained from the robot controller, in the form of a matrix. w T t express.

[0102] Therefore, the three-dimensional spatial information of the weld point location acquired by the vision sensor 3 can be obtained in the base coordinate system O through matrix transformation. W The following is the three-dimensional spatial information. That is: P w = w T t t T c P c P W Base coordinate system O W At a certain point in the middle, P C Camera coordinate system O C A certain point in the middle.

[0103] In some embodiments of the present invention, Euler angles are defined for the robot welding process, in the end effector coordinate system O. t Establish a direction vector containing Euler angles and project it onto the base coordinate system O. W The following is converted into an indicator vector, including:

[0104] In the robot end effector coordinate system O t Within, generate direction vectors emanating from the origin that coincide with the X, Y, and Z axes, respectively. Where the X-axis represents the forward direction of the welding torch, the Y-axis represents the horizontal direction of the welding torch, and the Z-axis represents the vertical direction of the welding torch; that is, the direction vector in the XY plane. The angle between the direction and the X-axis is the Euler angle α; the direction vector in the XZ plane. The angle between the Z-axis and the Y-axis is the Euler angle b; the direction vector in the YZ plane. The angle between the Y-axis and the Y-axis is the value of Euler angle c;

[0105] The direction vectors are all transformed by the space transformation matrix. w T t Obtain the base coordinate system OW The following indicator vectors include: deflection indicator vector Pitch indicator vector Rotation indicator vector

[0106] Specifically, the robot's end effector coordinate system is O t -X t Y t Z t Within it, generate three unit vectors coinciding with the three axes, originating from the origin. This is used to bind the welding torch 2 to its initial position, indicating the initial position of the welding torch 2.

[0107] As attached Figure 4 Appendix Figure 7 and attached Figure 10 As shown, the displacement in the x-direction is dx, the displacement in the y-direction is dy, and the displacement in the z-direction is dz. In the robot's end effector coordinate system O... t Within the XY plane, the value of Euler angle 'a' is defined as the angle between a vector and the X-axis. Therefore, adjusting the value of 'a' requires using a direction vector coinciding with the X-axis direction. Indication. When the value of the Euler angle α changes, the welding torch 2 generates a rotational motion about the Z-axis in the XY plane, with the direction vector... It will change accordingly.

[0108] For example, when the welding torch deflection angle (Euler angle α) is θ, Let the spatial transformation matrix be... Through spatial transformation matrix w T t , direction vector Projection vector in the base coordinate system Right now, vector It is the welding torch deflection indicator vector in the base coordinate system. This indicates the deflection posture of welding torch 2 at this time.

[0109] Similarly, the value of Euler angle b is defined as the angle between a vector in the XZ plane and the Z-axis. Therefore, adjusting the value of b requires using a direction vector coinciding with the Z-axis direction. Indication, via spatial transformation matrix w T t , thus obtaining the direction vector Projection vector in the base coordinate system vector It is the welding torch pitch indicator vector in the base coordinate system. This indicates the pitch position of welding torch 2 at this time.

[0110] The value of Euler angle c is defined as the angle between a vector in the YZ plane and the Y-axis. Therefore, adjusting the value of c requires using a direction vector that coincides with the Y-axis direction. Indication, via spatial transformation matrix w T t , thus obtaining the direction vector Projection vector in the base coordinate system vector It is the welding torch rotation indicator vector in the base coordinate system, through the rotation indicator vector This indicates the rotational posture of welding torch 2 at this time.

[0111] Through calibration, three vectors indicating the attitude are obtained.

[0112] It should be noted that a special case is also defined: when the direction vector coincides with the coordinate axis, that is:

[0113] In the XY plane, when dx = 0 and dy > 0, a is -90°; when dx = 0 and dy < 0, a is 90°; when dy = 0 and dx < 0, a is 0°; when dy = 0 and dx > 0, a is 180°; when dx < 0, a = arctan(dy / dx) / π × 180°; when dx > 0, a = arctan(dy / dx) / π × 180° - 180°.

[0114] In the XZ plane, when dz = 0 and dx > 0, b is -90°; when dz = 0 and dx < 0, b is 90°; when dx = 0 and dz < 0, b is 0°; when dx = 0 and dz > 0, b is 180°; when dz < 0, b = arctan(dx / dz) / π × 180°; when dz > 0, b = arctan(dx / dz) / π × 180° - 180°.

[0115] In the YZ plane, when dy = 0 and dz > 0, c is -90°; when dy = 0 and dz < 0, c is 90°; when dz = 0 and dy < 0, c is 0°; when dz = 0 and dy > 0, c is 180°; when dy < 0, c = arctan(dz / dy) / π × 180°; when dy > 0, b = arctan(dz / dy) / π × 180° - 180°.

[0116] For adjusting the Euler angles a, b, and c values ​​in non-special cases, indicator vectors are used for subsequent calculations.

[0117] In some embodiments of the present invention, initializing the position of the welding torch 2 according to the direction vector containing Euler angles includes:

[0118] According to the base coordinate system O WWith camera coordinate system O C The positional relationship is used to obtain the initial distance of the weld in the base coordinate system O. W A series of coordinate points are obtained and projected onto the base coordinate system O. W By examining the XY and XZ planes, a series of two-dimensional coordinate points within the corresponding planes can be obtained;

[0119] Based on a series of two-dimensional coordinate points in the corresponding plane, the initial distance of the weld in the base coordinate system O is obtained through least-squares fitting. W Fitted lines in the inner XY plane and XZ plane;

[0120] Move the welding torch 2 to its position in the base coordinate system O. W The projection points of the XY plane and XZ plane are located at the midpoint of the fitted straight line of the corresponding plane to complete the initialization of the position of welding gun 2.

[0121] Specifically, since the vision sensor 3 is located in front of the welding torch 2, the initial distance of the weld seam has already fallen into the detection range 4 of the vision sensor before welding begins. This weld seam data is used to initialize the welding torch posture.

[0122] For example, the vision sensor 3 collects a series of coordinate points (x, y) in a base coordinate system before welding with the welding torch 2. w y w , z w Projecting this onto the XY plane within the base coordinate system yields a series of two-dimensional coordinate points in the XY plane: (x1, y1), (x2, y2), (x3, y3)...(x...). n y n Since the initial distance of the weld seam collected is not long, it can be approximated as a straight line. Therefore, the least squares fitting method is used here to obtain the fitting line of the weld seam in the XY plane: y1 = a0x + b0, where (a0, b0) are the parameters of the fitting line. Since this straight line is very short, the midpoint of this straight line can be used as the initial position point of the welding torch 2. The position of the welding torch is moved so that the projection point of the welding torch 2 in the XY plane in the base coordinate system is located at the midpoint of the fitting line y1 in this plane, thus completing the initialization of the welding torch position.

[0123] Similarly, the vision sensor 3 collects a series of coordinate points in the base coordinate system before welding with the welding torch 2, projects these points onto the XZ plane, and obtains a series of two-dimensional coordinate points in the XZ plane: (z1, x1), (z2, x2), (z3, x3)...(z... n x nThe least squares fitting method is used to obtain the fitted straight line of the weld segment in the XZ plane: x1 = a0z + b0, where (a0, b0) are the parameters of the fitted straight line. The welding torch position is moved so that the projection point of welding torch 2 in the XZ plane in the base coordinate system is located at the midpoint of the fitted straight line x1 in this plane, thus completing the initialization of the welding torch position.

[0124] It should be noted that, since the weld information is compressed in the YZ plane of the base coordinate system, the complete weld curve cannot be seen in this plane. Since the initialization of the other two planes has already determined the spatial position of the welding torch, the YZ plane no longer provides the spatial position coordinates of the weld feature points of the initial weld distance.

[0125] In some embodiments of the present invention, the orientation of the welding torch 2 is initialized according to the direction vector containing Euler angles, including:

[0126] Control the attitude of welding torch 2 in the robot end effector coordinate system O t Inside, the Euler angles a, b, and c are all set to 0 to initialize the welding torch 2 posture.

[0127] In some embodiments of the present invention, calculating the values ​​of a and b of the Euler angles when the welding torch 2 is in contact with the weld seam based on the indicator vector includes:

[0128] According to the base coordinate system O W With camera coordinate system O C Based on the positional relationship, the welding distance of the weld in the next time period is obtained in the base coordinate system O. W A series of coordinate points are obtained and projected onto the base coordinate system O. W The XY and XZ planes are used to obtain a series of two-dimensional coordinate points in the corresponding planes;

[0129] Based on a series of two-dimensional coordinate points in the corresponding plane, the welding distance of the weld in the next time period in the base coordinate system O is obtained by least squares fitting. W Multiple fitted lines in the XY plane and multiple fitted lines in the XZ plane;

[0130] In the corresponding plane, multiple fitted straight lines are refitted into a continuous weld curve equation using a smooth transition algorithm, including: Y XY =f XY (X), X XZ =f XZ (Z); where Y XY Base coordinate system O W The weld curve fitted in the lower XY plane, f XY (X) is its weld curve equation; X XZ Let O be the base coordinate system W The weld curve fitted in the lower XZ plane, fXZ (Z) is its weld curve equation;

[0131] According to the deflection indicator vector With weld curve equation Y XY =f XY (X) is used to calculate the value of Euler angle α when the welding torch is in contact with the weld seam based on the preset geometric relationship.

[0132] According to the pitch indicator vector With weld curve equation X XZ =f XZ (Z) The pre-defined geometric relationship is used to calculate the value of the Euler angle b when the welding torch is in contact with the weld.

[0133] Among them, the welding process implementation path is collected by vision sensor 3, and the feature points scanned on the welding path are fitted into the weld curve equation.

[0134] Specifically, as the robot moves, vision sensor 3 collects welding distance information for the weld seam in the next time period, transforms it into a series of coordinate points in the base coordinate system through matrix transformation, projects them onto the XY plane, and fits them into a new straight line equation {y t}={y2,y3…y n Here, a piecewise fitting approach is used. Then, these fitted linear equations are refitted using a smooth transition algorithm to form a continuous weld curve and its equation Y. XY =f XY (X) represents the weld seam that the welding torch will pass through in the next time period.

[0135] Similarly, vision sensor 3 collects welding distance information for the weld seam in the next time period, transforms it into a series of coordinate points in the base coordinate system through matrix transformation, projects it onto the XZ plane, and fits it into a new straight line equation {x t}={x2,x3……x n}, and then refit a continuous weld curve and its curve equation f using a smooth transition algorithm. XZ =f XZ (Z) represents the weld seam that the welding torch will pass through in the next time period.

[0136] In some embodiments of the present invention, calculating the value of the Euler angle c when the welding torch 2 is in contact with the weld seam based on the indicator vector includes:

[0137] According to the base coordinate system O W With camera coordinate system O C The positional relationship is used to obtain the weld point and the weldment points on both sides of the weld at the current moment in the base coordinate system O. W A series of coordinate points are obtained and projected onto the base coordinate system O. WThe YZ plane is used to obtain a series of two-dimensional coordinate points within the YZ plane;

[0138] Based on a series of two-dimensional coordinate points in the YZ plane, the inclined straight line Z of the weldment surface is obtained by least squares fitting. YZ =f YZ (Y); where Z YZ Base coordinate system O W The inclined straight line of the weldment surface fitted in the lower YZ plane, f YZ (Y) is the equation of the straight line with the inclined surface of the weldment;

[0139] According to the slewing indicator vector Slant Z of the weldment surface YZ =f YZ (Y) is the preset geometric relationship, and the value of c of Euler angle is calculated when the welding torch is attached to the weld.

[0140] Specifically, since the appropriate rotation posture of the welding torch 2 is adjusted according to the inclination of the workpiece surface, the vision sensor 3 collects the current weld seam information and information on several points on the workpiece surface on both sides of the weld seam (along the y-axis direction in the YZ plane), converts them into coordinate points, projects them onto the YZ plane under the base coordinates, obtains a series of two-dimensional coordinate points in the YZ plane, and uses the least squares method to fit a straight line Z of the workpiece surface inclination. YZ =f YZ (Y) represents the degree of inclination of the upper surface of the weldment at a certain point through a cross section parallel to the YZ plane.

[0141] In some embodiments of the present invention, the predetermined geometric relationship between each indicator vector and the weld curve equation includes:

[0142] In the base coordinate system O W In the XY plane below, the deflection indicator vector Equation of weld curve Y in the XY plane XY =f XY The direction vector of the tangent line to (X) is parallel;

[0143] In the base coordinate system O W In the XZ plane below, the pitch indicator vector Equation of weld curve with respect to the XZ plane X XZ =f XZ The direction vector of the normal to (Z) is parallel;

[0144] In the base coordinate system O W In the YZ plane below, the rotation indicator vector Slant Z of the weldment surface YZ =f YZThe direction vector of the normal to (Y) is parallel.

[0145] Specifically, when welding torch 2 is in contact with the weld seam, the orientation of welding torch 2 coincides with the weld seam, the pitch of welding torch 2 is perpendicular to the undulations of the weld seam, and the rotation of welding torch 2 tilts with the surface of the workpiece. That is, the deflection indicator vector is parallel to the tangent of the weld seam curve in the XY plane, i.e., parallel to its direction vector; the pitch indicator vector... The direction vector is perpendicular to the tangent of the weld curve in the XZ plane, that is, parallel to the direction vector of its normal; rotation indicator vector. It is perpendicular to the inclined straight line of the weldment surface, that is, parallel to the direction vector of its normal.

[0146] In some embodiments of the present invention, calculating the Euler angles a, b, and c when the welding torch 2 is in contact with the weld seam includes:

[0147] According to the base coordinate system O W With camera coordinate system O C Based on the positional relationship, obtain the coordinates of the welding point in the base coordinate system at the next welding moment of the weld seam, and project it onto the base coordinate system O. W The XY, XZ, and YZ planes are used to obtain the base coordinate system O. W Let the coordinates of point A(x0, y0), point B(z0, x0), and point C(y0, z0) be the coordinates of the points A, B, and C respectively.

[0148] Then the weld curve equation Y XY =f XY The equation of the tangent line to (X) at coordinate point A is: y - y0 = f′(x0)(x - x0), and one direction vector of the tangent line equation is:

[0149] Weld curve equation f XZ =f XZ The equation of the normal line (Z) at coordinate point B is: One direction vector of its normal equation is:

[0150] The weldment surface is inclined straight line Z YZ =f YZ The equation of the normal line (Y) at coordinate point C is: One direction vector of its normal equation is:

[0151] Obtain the spatial transformation matrix as

[0152] Calculate the deflection indicator vector

[0153] Calculate the pitch indicator vector

[0154] Calculate the slewing indicator vector

[0155] Where θ1 is the value of Euler angle a, θ2 is the value of Euler angle b, and θ3 is the value of Euler angle c; m, n, u, and v correspond to the spatial transformation relationship between the robot base and the welding torch, and are all preset values; f′(x0) is the curve equation f XY (X) is the derivative of f at coordinate point A; f′(z0) is the equation of the curve f XZ (Z) is the derivative at coordinate point B; f′(y0) is the equation of the curve f YZ (Y) is the derivative of the coordinate point C;

[0156] The value of α for the Euler angle when welding torch 2 is in contact with the weld is calculated as follows:

[0157]

[0158] The value of 'b' for the Euler angle when welding torch 2 is in contact with the weld is calculated as follows:

[0159]

[0160] The value of c for the Euler angle when welding torch 2 is in contact with the weld is calculated as follows:

[0161]

[0162] The following examples illustrate the adjustment principles and effects of the present invention by showing how to adjust the welding torch's deflection, pitch, and rotation attitudes. In the following examples, the spatial transformation matrix...

[0163] As attached Figure 3a Appendix Figure 3b Appendix Figure 3c Appendix Figure 3d As shown, in one embodiment, a weldment 6 with a three-dimensional curved weld seam 5 has undulating and curved weld seam 5. In the base coordinate system, its front view is located in the YZ plane, its top view is located in the XY plane, and its side view is located in the XZ plane.

[0164] As attached Figure 5 As shown, the initial deflection attitude 11 of the welding torch and the target deflection attitude 13 of the welding torch are shown. The deflection attitude is indicated by the deflection indicator vector. Indicates the direction vector The angle θ1 between the X-axis and the x-axis is the value of 'a' for the Euler angle to be calculated. The calculation process is as follows:

[0165] Based on the geometric meaning of the derivative and applying the point-slope form of a straight line, the equation of the weld curve Y can be determined. XY =fXY The equation of the tangent line to (X) at a point A(x0, y0) is:

[0166] y-y0=f′(x0)(x-x0);

[0167] Then one direction vector of the tangent equation is:

[0168]

[0169] When the welding torch is aligned with the weld seam, i.e., the deflection indicator vector... With weld curve Y XY =f XY The tangent of (X) is parallel, that is, parallel to the direction vector of the tangent of the weld curve.

[0170] Deflection indicator vector

[0171] Let its direction vector be the tangent to the weld fitting curve. Parallel, that is,

[0172] Then the value of the deflection angle θ1:

[0173]

[0174] The θ1 value is the angle of deflection that the welding torch should be adjusted to at point A.

[0175] In this embodiment, as shown in the appendix Figure 6 As shown, the initial deflection posture 15 of the welding torch and the adjusted deflection posture 16 are aligned with the weld seam 5. If no adjustment is made, the unadjusted deflection posture 17 is the same as the initial deflection posture 15, which is not conducive to welding. This schematic diagram shows that by adjusting the deflection angle, the orientation of the welding torch 2 can be aligned with the weld seam at any position.

[0176] In one embodiment, as shown in the appendix Figure 8 As shown, the initial pitch attitude 21 of the welding torch and the target pitch attitude 22 of the welding torch are shown. The pitch attitude is indicated by the pitch indicator vector. Indicates the direction vector The angle θ2 between the center and the Z-axis is the value of the Euler angle b to be calculated. The calculation process is as follows:

[0177] Weld curve equation f XZ =f XZ The equation of the normal line (Z) at point B(z0, x0) is:

[0178]

[0179] Then one direction vector of the normal equation is:

[0180]

[0181] In order for the welding torch 2 to adjust its pitch attitude according to the rise and fall of the weld seam 5, it needs to remain perpendicular to the weld seam 5, i.e., the pitch indicator vector. With weld curve f XZ =f XZ The direction vector of the normal to (Z) parallel.

[0182] Pitch indicator vector Let it be the same as the direction vector When parallel, that is,

[0183]

[0184] Then the value of the pitch angle θ2 is:

[0185]

[0186] The value of θ2 is the angle of the pitch position that the welding torch 2 should be adjusted at point B.

[0187] In this embodiment, as shown in the appendix Figure 9 As shown, the initial pitch angle of the welding torch is 24. The pitch angle 25 before adjustment is the same as the initial pitch angle 24, while the pitch angle 26 after adjustment is perpendicular to the weld seam 5. This schematic diagram shows that by adjusting the pitch angle, the pitch angle of the welding torch can be made perpendicular to the weld seam at any position.

[0188] In one embodiment, as shown in the appendix Figure 11 As shown, the initial pitch attitude of the welding torch is 30, and the target pitch attitude of the welding torch is 32. Its rotation attitude is indicated by the rotation indicator vector. Indicates the direction vector The angle θ3 between the Y-axis and the Y-axis is the c value of the Euler angle that needs to be calculated.

[0189] The weldment surface is inclined straight line Z YZ =f YZ The equation of the normal line of (Y) at point C(y0, z0) is:

[0190]

[0191] Then one direction vector of the normal equation is:

[0192]

[0193] To ensure that the rotation posture of welding torch 2 tilts according to the inclination of the workpiece surface, it is necessary to maintain the perpendicularity of welding torch 2 to the weld surface, i.e., the rotation indicator vector. Slant Z of the weldment surface YZ =f YZ The direction vector of the normal to (Y) parallel.

[0194] Rotation indicator vector Let it be the same as the direction vector When parallel, that is,

[0195]

[0196]

[0197] The θ3 value is the angle value of the rotation posture that the welding torch 2 should be adjusted at point C.

[0198] In this embodiment, as shown in the appendix Figure 12 As shown, the initial rotation posture 34 of the welding torch and the rotation posture 36 before adjustment are consistent with the initial rotation posture 34. The rotation posture 35 of the welding torch after adjustment is perpendicular to the upper surface of the weld in the YZ plane. This schematic diagram shows that by adjusting the rotation angle, the rotation posture of the welding torch can be made to remain perpendicular to the weld surface at any position.

[0199] In addition, the present invention also provides a three-dimensional curved surface welded seam robot system, which is applied to a method for real-time posture adjustment during the welding process of a three-dimensional curved surface welded seam robot.

[0200] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0201] 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 real-time posture adjustment during the welding process of a three-dimensional curved surface weld robot, used in a robot welding system, the robot welding system comprising: A robot base, a welding torch connected to the robot base, and a vision sensor disposed at the welding torch, characterized in that it includes: A matrix representing the relative positions of the components of the robot welding system is calibrated, and a spatial coordinate system is established. This spatial coordinate system includes: the base coordinate system O where the robot base is located. W The coordinate system O of the end effector where the welding torch is located t The camera coordinate system O where the visual sensor is located C ; Define Euler angles for the robot welding process, where each Euler angle includes a, b, and c values. The a value is defined as the deflection angle of the welding torch, the b value as the pitch angle of the welding torch, and the c value as the rotation angle of the welding torch. In the end effector coordinate system O... t An internal direction vector containing Euler angles is established, and it is projected from the camera coordinate system onto the base coordinate system to be transformed into an indicator vector. Initialize the welding torch attitude and position based on the direction vector containing Euler angles; The vision sensor acquires weld seam information and calculates the values ​​of Euler angles a, b, and c when the welding torch is in contact with the weld seam based on the indicated vector. Adjust the welding torch posture according to the Euler angles a, b, and c values ​​when the welding torch is in contact with the weld seam. In the end effector coordinate system O t An internal direction vector containing Euler angles is established, and it is projected from the camera coordinate system onto the base coordinate system, transforming it into an indicator vector, including: In the robot end effector coordinate system O t Within, generate direction vectors emanating from the origin that coincide with the X, Y, and Z axes, respectively. , , Where the X-axis represents the forward direction of the welding torch, the Y-axis represents the horizontal direction of the welding torch, and the Z-axis represents the vertical direction of the welding torch; that is, the direction vector in the XY plane. The angle between the direction and the X-axis is the Euler angle α; the direction vector in the XZ plane. The angle between the Z-axis and the Z-axis is the Euler angle b; the direction vector in the YZ plane. The angle between the Y-axis and the Y-axis is the value of Euler angle c; The direction vectors are all transformed by the space transformation matrix. w T t The base coordinate system O is obtained W The following indicator vectors include: deflection indicator vector Pitch indicator vector Rotation indicator vector ; The step of calculating the Euler angles a and b when the welding torch is in contact with the weld seam based on the indicated vector includes: According to the base coordinate system O W With respect to the camera coordinate system O C Based on the positional relationship, the welding distance of the weld in the next time period is obtained in the base coordinate system O. W A series of coordinate points are obtained and projected onto the base coordinate system O. W The XY and XZ planes are used to obtain a series of two-dimensional coordinate points in the corresponding planes; Based on a series of two-dimensional coordinate points in the corresponding plane, the welding distance of the weld in the next time period in the base coordinate system O is obtained by least squares fitting. W Multiple fitted lines in the XY plane and multiple fitted lines in the XZ plane; Within the corresponding plane, multiple fitted straight lines are refitted into a continuous weld curve equation using a smooth transition algorithm, including: , ;in, Base coordinate system O W The weld curve fitted in the lower XY plane, The equation for its weld curve is given. Base coordinate system O W The weld curve fitted in the lower XZ plane, The equation for its weld curve is given. According to the deflection indicator vector With the weld curve equation Based on the preset geometric relationship, calculate the value of Euler angle α when the welding torch is in contact with the weld. According to the pitch indicator vector With the weld curve equation Based on the preset geometric relationship, calculate the value of the Euler angle b when the welding torch is in contact with the weld. Wherein, the deflection indicator vector With the weld curve equation The preset geometric relationship is in the base coordinate system O W In the XY plane below, the deflection indicator vector Equation of weld curve with respect to the XY plane The direction vector of the tangent is parallel; The pitch indicator vector With the weld curve equation The preset geometric relationship is in the base coordinate system O W In the XZ plane below, the pitch indication vector Equation of weld curve with respect to the XZ plane The direction vector of the normal is parallel.

2. The method for real-time posture adjustment of a three-dimensional curved surface weld robot during welding as described in claim 1, characterized in that, The Euler angle c value when the welding torch is in contact with the weld seam is calculated based on the indicated vector, including: According to the base coordinate system O W With the camera coordinate system O C The positional relationship is used to obtain the weld point and the weldment points on both sides of the weld at the current moment in the base coordinate system O. W A series of coordinate points are obtained and projected onto the base coordinate system O. W The YZ plane is used to obtain a series of two-dimensional coordinate points within the YZ plane; Based on a series of two-dimensional coordinate points in the YZ plane, the inclined straight line of the weldment surface is obtained by least squares fitting. ;in, Base coordinate system O W The inclined straight line of the weldment surface fitted in the lower YZ plane. The equation for the straight line with the inclined surface of the weldment; According to the gyration indicator vector Inclined straight line with the surface of the weldment Based on the preset geometric relationship, calculate the value of the Euler angle c when the welding torch is in contact with the weld. The slewing indicator vector Inclined straight line with the surface of the weldment The preset geometric relationship is in the base coordinate system O W In the YZ plane below, the rotation indicator vector Inclined straight line with the surface of the weldment The direction vector of the normal is parallel.

3. The method for real-time posture adjustment of a three-dimensional curved surface weld robot during welding as described in claim 1, characterized in that, The welding torch position is initialized based on the direction vector containing Euler angles, including: According to the base coordinate system O W With the camera coordinate system O C The positional relationship is used to obtain the initial distance of the weld in the base coordinate system O. W A series of coordinate points are obtained and projected onto the base coordinate system O. W By examining the XY and XZ planes, a series of two-dimensional coordinate points within the corresponding planes can be obtained; Based on a series of two-dimensional coordinate points in the corresponding plane, the initial distance of the weld in the base coordinate system O is obtained through least squares fitting. W Fitted lines in the inner XY plane and XZ plane; Move the welding torch to position it in the base coordinate system O. W The projection points of the XY and XZ planes are located at the midpoints of the fitted lines of the corresponding planes to complete the initialization of the welding gun position.

4. The method for real-time posture adjustment of a three-dimensional curved surface weld robot during welding as described in claim 1 or 3, characterized in that, The welding torch attitude is initialized based on the direction vector containing Euler angles, including: Control the welding torch posture in the robot end effector coordinate system O t Within this process, the Euler angles a, b, and c are all set to 0 to initialize the welding torch posture.

5. The method for real-time posture adjustment of a three-dimensional curved surface weld robot during welding as described in claim 2, characterized in that, Calculate the Euler angles a, b, and c when the welding torch is in contact with the weld, including: According to the base coordinate system O W With the camera coordinate system O C Based on the positional relationship, obtain the coordinates of the welding point at the next welding moment of the weld in the base coordinate system, and project it onto the base coordinate system O. W The XY, XZ, and YZ planes are used to obtain the base coordinate system O. W lower coordinate point Coordinates Coordinate point C ; Then the equation of the weld curve The equation of the tangent line at coordinate point A is: One direction vector of its tangent equation is: ; The weld curve equation The equation of the normal line at coordinate point B is: One direction vector of its normal equation is: ; The surface of the weldment is inclined in a straight line. The equation of the normal line at coordinate point C is: One direction vector of its normal equation is: ; The spatial transformation matrix is ​​obtained as follows: ; Calculate the deflection indicator vector ; Calculate the pitch indicator vector ; Calculate the slewing indicator vector ; in, Let α be the value of the Euler angle. Let b be the value of the Euler angle. c represents the Euler angles; m, n, u, and v correspond to the spatial transformation relationship between the robot base and the welding torch, and are all preset values. Equation of the curve The derivative at coordinate point A; Equation of the curve The derivative at coordinate point B; Equation of the curve The derivative at coordinate point C; The value of α for the Euler angle when the welding torch is in contact with the weld is calculated as follows: ； The value of 'b' for the Euler angle when the welding torch is in contact with the weld is calculated as follows: ； The value of c for the Euler angle when the welding torch is in contact with the weld is calculated as follows: 。 6. A three-dimensional curved surface welding robot system, characterized in that, The method for real-time posture adjustment of a three-dimensional curved surface weld robot during welding process, as described in any one of claims 1-5.

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