Moving shaft calibration and processing method and processing platform

Abstract

The invention discloses a moving shaft calibration and machining method and a machining platform, is applied to the machining platform with a 3D camera and a multi-axis movement mechanism, and belongs to the technical field of machining.The moving shaft calibration and machining method comprises the steps that the multi-axis movement mechanism is controlled to drive a calibration ball to move along a plurality of moving shafts, controlling the 3D camera to obtain point cloud data generated by movement of the calibration ball, and constructing a first transformation matrix from a 3D pixel coordinate system of the 3D camera to a multi-axis space coordinate system of the multi-axis movement mechanism according to the movement coordinates of the calibration ball driven by the multi-axis movement mechanism and the point cloud data; controlling the 3D camera to obtain a height map scanned by the processing object, extracting a plurality of track feature points according to the height map, and outputting space track data corresponding to the multi-axis space coordinate system according to the track feature points in combination with the first transformation matrix; and the processing platform is controlled to process the processing object according to the space trajectory data, so that the processing precision is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of machining, and particularly relates to a method for calibrating and machining a moving axis and a machining platform. Background Art

[0002] Considering the forming requirements of the curved surface shape of the battery cell product, some battery cell products need to be welded to form a curved surface.

[0003] In the related art, due to factors such as mechanical manufacturing and installation, there are certain deviations or errors in the moving axes of the machining platform, thereby affecting the welding accuracy of the battery cells. Summary of the Invention

[0004] The present invention aims to at least solve one of the technical problems existing in the prior art. For this purpose, the present invention provides a method for calibrating and machining a moving axis, which is beneficial to improving the machining accuracy.

[0005] The present invention also provides a machining platform.

[0006] The present invention also provides a computer-readable storage medium.

[0007] According to the method for calibrating and machining a moving axis according to the first aspect embodiment of the present invention, which is applied to a machining platform having a 3D camera and a multi-axis motion mechanism, the method for calibrating and machining a moving axis includes:

[0008] Controlling the multi-axis motion mechanism to drive a calibration ball to move along multiple moving axes, and controlling the 3D camera to acquire point cloud data generated by the movement of the calibration ball, and constructing a first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism according to the moving coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data;

[0009] Controlling the 3D camera to acquire a height map of the scanned machining object, extracting multiple trajectory feature points from the height map, and outputting spatial trajectory data corresponding to the multi-axis space coordinate system according to the trajectory feature points in combination with the first transformation matrix;

[0010] Controlling the machining platform to machine the machining object according to the spatial trajectory data.

[0011] The mobile axis calibration and machining method according to the embodiments of the present invention has at least the following beneficial effects: After the user places the calibration ball on the multi-axis motion mechanism, the mobile axis calibration and machining method can control the multi-axis motion mechanism to drive the calibration ball to move along multiple mobile axes, and control the 3D camera to obtain the point cloud data generated by the movement of the calibration ball. According to the movement coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data, a first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism is constructed, that is, the pose of the mobile axis of the multi-axis motion mechanism is calibrated by the calibration ball and the 3D camera, so as to obtain the first transformation matrix, which is beneficial to improving the mapping accuracy between the 3D pixel coordinate system and the multi-axis space coordinate system. The mobile axis calibration and machining method can control the 3D camera to scan the machining object to obtain the height map of the machining object scan, extract multiple trajectory feature points according to the height map, and output the space trajectory data corresponding to the multi-axis space coordinate system according to the trajectory feature points and the first transformation matrix. The mobile axis calibration and machining method can control the machining platform to perform machining guidance on the machining object according to the space trajectory data to realize the shaping surface shape of the machining object. The mobile axis calibration and machining method calibrates the mobile axis of the multi-axis motion mechanism through the calibration ball and the 3D camera, which is beneficial to reducing the error of the conversion between the trajectory feature points and the space trajectory data and improving the machining accuracy of the machining object.

[0012] According to some embodiments of the present invention, the machining platform further includes a 2D camera, and the 2D camera applies a 2D pixel coordinate system;

[0013] The mobile axis calibration and machining method further includes: constructing a second transformation matrix from the 3D pixel coordinate system to the 2D pixel coordinate system according to the first transformation matrix, the first coordinate of the marked point on the calibration block collected in the 3D pixel coordinate system, and the second coordinate in the 2D pixel coordinate system;

[0014] Outputting the space trajectory data corresponding to the multi-axis space coordinate system according to the trajectory feature points and the first transformation matrix includes: obtaining the trajectory coordinates of the trajectory feature points in the 2D pixel coordinate system according to the second transformation matrix, optimizing the trajectory coordinates, and then outputting the space trajectory data corresponding to the optimized trajectory coordinates in combination with the first transformation matrix.

[0015] According to some embodiments of the present invention, controlling the multi-axis motion mechanism to drive the calibration ball to move along multiple mobile axes includes:

[0016] Setting different multiple groups of starting points, and controlling the multi-axis motion mechanism to drive the calibration ball to calibrate the pose of the mobile axis from the multiple groups of starting points respectively; in one calibration, the calibration ball moves a preset distance along multiple mobile axes respectively.

[0017] According to some embodiments of the present invention, the multiple mobile axes are respectively the X axis, the Y axis, and the Z axis;

[0018] Control the multi-axis motion mechanism to drive the calibration ball from multiple starting points respectively to calibrate the pose of the moving axis; in one calibration, the calibration ball moves a preset distance along multiple moving axes respectively, including:

[0019] Perform multiple calibrations. In one calibration, the multi-axis motion mechanism drives the calibration ball to move a preset distance along the X-axis, Y-axis, and Z-axis respectively, and obtain a point cloud map of the calibration ball. The point cloud data includes the point cloud map.

[0020] According to some embodiments of the present invention, construct a first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism according to the moving coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data, including:

[0021] Adopt an optimization search algorithm to reduce the error between the point cloud of the calibration ball and the center of the ball, and solve the direction vectors corresponding to multiple moving axes, indicating the installation deviation of the moving axes;

[0022] Optimize the first transformation matrix according to the direction vectors.

[0023] According to some embodiments of the present invention, adopt an optimization search algorithm to reduce the error between the point cloud of the calibration ball and the center of the ball, and solve the direction vectors corresponding to multiple moving axes, including:

[0024] According to multiple point cloud maps, adopt a non-linear optimization method to reduce the error between the point cloud of the calibration ball and the center of the ball, and solve the direction vector of the X-axis, the direction vector of the Y-axis, and the direction vector of the Z-axis. The optimization search algorithm is a non-linear optimization method.

[0025] According to some embodiments of the present invention, adopt an optimization search algorithm to reduce the error between the point cloud of the calibration ball and the center of the ball, and solve the direction vectors corresponding to multiple moving axes, including:

[0026] The optimization search algorithm is calculated using the following objective function:

[0027]

[0028] Where, V x is the direction vector of the X-axis, V y is the direction vector of the Y-axis, V z is the direction vector of the Z-axis, P c is the center coordinate of the calibration ball in the multi-axis space coordinate system, R is the standard radius of the calibration ball, ΔT i is a set of measurement points (u i , v i ) on the spherical surface of the calibration ball corresponding to the movement amount, M Δ is the transformation matrix of the movement amount.

[0029] According to some embodiments of the present invention, optimizing the first transformation matrix according to the direction vector includes:

[0030] In a multi-axis space coordinate system, let the direction vector of the X-axis be V x =(v xx , v xy , v xz ) T , the direction vector of the Y-axis is

[0031] V y =(v yx , v yy , v yz ) T , the direction vector of the Z-axis is V z =(v zx , v zy , v zz ) T ; Let the point (x, y, z) in the multi-axis space coordinate system move ΔT = (Δx, Δy, -Δz) T after the X-axis, Y-axis and Z-axis movements, and its coordinates in the 3D pixel coordinate system are (u, v);

[0032] The first transformation matrix is obtained as

[0033] where M Δ is the transformation matrix of the movement amount and is transformed by the following expression:

[0034]

[0035] According to some embodiments of the present invention, the processing object is an electric core, the processing platform is a welding platform, the welding platform is used for welding the electric core, and the welding platform further includes a galvanometer of a welding laser. Both the galvanometer and the 2D camera apply the 2D pixel coordinate system;

[0036] Or, the processing object is an electric core, the processing platform is a dispensing platform, and the dispensing platform is used for dispensing the electric core;

[0037] Or, the processing object is an electric core, the processing platform is a cutting platform, and the cutting platform is used for cutting the electric core.

[0038] The processing platform according to the second aspect embodiment of the present invention includes: a 3D camera and a multi-axis motion mechanism, which are used to implement the moving axis calibration and processing method as described in any item of the first aspect.

[0039] The processing platform according to the embodiments of the present invention has at least the following beneficial effects: The processing platform is used to implement the moving axis calibration and processing method as shown in any one of the first aspects. After the user places the calibration ball on the multi-axis motion mechanism, the moving axis calibration and processing method can control the multi-axis motion mechanism to drive the calibration ball to move along multiple moving axes, and control the 3D camera to obtain the point cloud data generated by the movement of the calibration ball. According to the movement coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data, a first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism is constructed, that is, the pose of the moving axis of the multi-axis motion mechanism is calibrated by the calibration ball and the 3D camera, so as to obtain the first transformation matrix, which is beneficial to improving the mapping accuracy between the 3D pixel coordinate system and the multi-axis space coordinate system. The moving axis calibration and processing method can control the 3D camera to scan the processing object to obtain the height map of the processed object, extract multiple trajectory feature points according to the height map, and output the space trajectory data corresponding to the multi-axis space coordinate system according to the trajectory feature points combined with the first transformation matrix. The moving axis calibration and processing method can control the processing platform to guide the processing of the processing object according to the space trajectory data to realize the shape of the formed surface of the processing object. The moving axis calibration and processing method calibrates the moving axis of the multi-axis motion mechanism through the calibration ball and the 3D camera, which is beneficial to reducing the error of the conversion between the trajectory feature points and the space trajectory data and improving the processing accuracy of the processing object.

[0040] The computer-readable storage medium according to the embodiments of the third aspect of the present invention stores computer-executable instructions for causing a computer to execute the moving axis calibration and processing method as shown in any one of the first aspects.

[0041] The computer-readable storage medium according to an embodiment of the present invention has at least the following beneficial effects: The computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to cause a computer to execute the moving axis calibration and machining method according to any item in the first aspect. After a user places a calibration ball on a multi-axis motion mechanism, the moving axis calibration and machining method can control the multi-axis motion mechanism to drive the calibration ball to move along multiple moving axes, and control a 3D camera to obtain point cloud data generated by the movement of the calibration ball. According to the movement coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data, a first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism is constructed, that is, the pose of the moving axis of the multi-axis motion mechanism is calibrated by the calibration ball and the 3D camera, so as to obtain the first transformation matrix, which is beneficial to improving the mapping accuracy between the 3D pixel coordinate system and the multi-axis space coordinate system. The moving axis calibration and machining method can control the 3D camera to scan a machining object to obtain a height map of the scanned machining object, extract a plurality of trajectory feature points according to the height map, and output spatial trajectory data corresponding to the multi-axis space coordinate system according to the trajectory feature points in combination with the first transformation matrix. The moving axis calibration and machining method can control a machining platform to perform machining guidance on the machining object according to the spatial trajectory data to realize the shaped surface shape of the machining object. The moving axis calibration and machining method calibrates the moving axis of the multi-axis motion mechanism by the calibration ball and the 3D camera, which is beneficial to reducing the error in the conversion between the trajectory feature points and the spatial trajectory data and improving the machining accuracy of the machining object.

[0042] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The following further describes the present invention with reference to the drawings and embodiments, wherein:

[0044] Figure 1 is a layout schematic diagram of a machining platform of a moving axis calibration and machining method according to an embodiment of the present invention;

[0045] Figure 2 is a flowchart of a moving axis calibration and machining method according to an embodiment of the present invention;

[0046] Figure 3 is a flowchart of constructing a second transformation matrix and outputting spatial trajectory data of a moving axis calibration and machining method according to an embodiment of the present invention;

[0047] Figure 4 is a flowchart of calibrating a moving axis and obtaining a direction vector of the moving axis of a moving axis calibration and machining method according to an embodiment of the present invention;

[0048] Figure 5Flowchart for calibrating a moving axis and obtaining the direction vectors of the X-axis, Y-axis, and Z-axis in a method for calibrating and processing a moving axis according to an embodiment of the present invention. Detailed implementation

[0049] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation to the present invention.

[0050] In the description of the present invention, it should be understood that for the orientation description, such as up, down, etc., the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0051] In the description of the present invention, "plurality" refers to more than two. If there is a description of the first and the second, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0052] In the description of the present invention, unless otherwise clearly defined, terms such as "set", "install", "connect", etc. should be understood in a broad sense. Those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific content of the technical solution.

[0053] With the continuous in-depth research of the inventor in the field of battery cells, the inventor believes that the shaped curved surface battery cell is the future development trend of the battery cell shape. The shaped curved surface battery cell can adapt to a richer form of terminal products, and the shaped curved surface battery cell needs to consider welding guidance. The current mainstream welding guidance scheme is six-axis welding guidance, which has advantages in product compatibility, but has defects such as low precision and slow running speed, and cannot meet the welding guidance requirements of the current battery cell size accuracy.

[0054] Refer to Figures 1 to 5 As shown, a method for calibrating and processing a moving axis according to an embodiment of the present invention is applied to a processing platform having a 3D camera, a multi-axis motion mechanism, a 2D camera, and a galvanometer of a welding laser. Specifically, the processing platform is a welding platform, the processing object is a battery cell, the welding platform is used for welding the battery cell, and the multi-axis motion mechanism can be a five-axis motion mechanism, including three moving axes and two rotating axes. Compared with six-axis welding guidance, five-axis welding guidance has obvious advantages in terms of cost, precision, and speed.

[0055] Refer toFigure 1 and Figure 2 As shown in Figure 2 , the mobile axis calibration and machining method includes the following steps:

[0056] Step S100: Control the multi-axis motion mechanism to drive the calibration ball to move along multiple mobile axes, and control the 3D camera to obtain the point cloud data generated by the movement of the calibration ball. Construct the first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism according to the movement coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data;

[0057] Step S200: Control the 3D camera to obtain the height map of the machined object scanned, extract multiple trajectory feature points from the height map, and output the spatial trajectory data corresponding to the multi-axis space coordinate system according to the trajectory feature points in combination with the first transformation matrix;

[0058] Step S300: Control the machining platform to machine the machined object according to the spatial trajectory data.

[0059] Refer to Figure 1 and Figure 2 As shown in Figure 1 and Figure 2 , in step S100, the user places the calibration ball in the multi-axis motion mechanism. The mobile axis calibration and machining method can control the multi-axis motion mechanism to drive the calibration ball to move along multiple mobile axes. The multi-axis motion mechanism can obtain the movement coordinates for driving the calibration ball to move. The calibration ball is scanned by the 3D camera, so as to obtain the point cloud data generated by the movement of the calibration ball.

[0060] Refer to Figure 1 and Figure 2 As shown in Figure 1 and Figure 2 , the mobile axis calibration and machining method constructs the first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism according to the movement coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data. That is, the pose of the mobile axis of the multi-axis motion mechanism is calibrated by the calibration ball and the 3D camera, so as to obtain the first transformation matrix, which is beneficial to improving the mapping accuracy between the 3D pixel coordinate system and the multi-axis space coordinate system and reducing the transformation error.

[0061] Refer to Figure 1 and Figure 2 As shown in Figure 1 and Figure 2 , in step S200, the user can install the machined object on the loading platform. The mobile axis calibration and machining method can scan the machined object through the 3D camera, that is, control the 3D camera to scan the image data in different product postures according to a fixed trajectory, so as to obtain the height map of the machined object scanned.

[0062] Refer to Figure 1 and Figure 2As shown, the moving axis calibration and machining method can extract multiple trajectory feature points from the height map. The trajectory feature points can be the coordinates of the flange or edge of the machining object, etc. The moving axis calibration and machining method can output the spatial trajectory data corresponding to the multi-axis spatial coordinate system according to the trajectory feature points combined with the first transformation matrix.

[0063] Referring to Figure 1 and Figure 2 As shown, in step S300, the moving axis calibration and machining method can control the machining platform to weld the machining object according to the obtained spatial trajectory data, so as to realize the shape of the formed surface of the machining object.

[0064] Referring to Figure 1 and Figure 2 As shown, the moving axis calibration and machining method provided by the embodiment of the present invention calibrates the moving axis of the multi-axis motion mechanism through a calibration ball and a 3D camera, which is beneficial to reducing the error of the conversion between the trajectory feature points and the spatial trajectory data and improving the welding accuracy of the machining object.

[0065] Referring to Figure 1 and Figure 2 As shown, it should be noted that the calibration ball is a sphere with known geometric features, such as having an accurate radius, spherical smoothness, etc., and is usually used for the calibration of sensors or mechanical systems. The 3D camera is specifically a 3D line-scanning laser camera, which is a three-dimensional imaging device based on line-scanning technology. By scanning the surface of an object and combining motion information, three-dimensional data is generated. The 3D line-scanning camera mainly uses line laser or structured light to project onto the surface of an object, and captures the reflected light signal through a sensor. Point cloud data is a discrete data set composed of a large number of three-dimensional coordinate points, and is mainly used to characterize the geometric shape of the object surface.

[0066] Referring to Figure 1 and Figure 3 As shown, it can be understood that in the machining platform, the 3D camera applies a 3D pixel coordinate system, the multi-axis motion mechanism applies a multi-axis spatial coordinate system, while the galvanometer and the 3D camera both apply a 2D pixel coordinate system.

[0067] The moving axis calibration and machining method further includes the following coordinates:

[0068] Step S400, according to the first transformation matrix, the first coordinates of the marked points on the calibration block in the 3D pixel coordinate system and the second coordinates in the 2D pixel coordinate system, construct the second transformation matrix from the 3D pixel coordinate system to the 2D pixel coordinate system.

[0069] Referring to Figure 1 and Figure 3As shown in the figure, in step S400, the moving axis calibration and machining method places the calibration block in the 3D pixel coordinate system and the 2D pixel coordinate system, so as to obtain the first coordinate of the marked point on the calibration block in the 3D pixel coordinate system and the second coordinate in the 2D pixel coordinate system, thereby constructing the second transformation matrix from the 3D pixel coordinate system to the 2D pixel coordinate system. Combining with the first transformation matrix, the moving axis calibration and machining method can realize the mutual conversion of the multi-axis space coordinate system, the 3D pixel coordinate system and the 2D pixel coordinate system, which is conducive to reducing the error of the conversion between the trajectory feature points and the space trajectory data through multiple calibrations and optimizations, and improving the welding accuracy of the machining object.

[0070] It should be noted that the galvanometer is used for high-speed and high-precision positioning in welding to determine the welding path, and the 2D camera is mainly used for visual guidance to ensure welding accuracy and reliability. The structures of the 3D camera, the multi-axis motion mechanism, the galvanometer and the 2D camera are all conventional technical means in the art and will not be elaborated here.

[0071] It should be understood that in some other embodiments, the machining object is an electric core, and the machining platform is a dispensing platform, which is used for dispensing the electric core.

[0072] It should be understood that in some other embodiments, the machining object is an electric core, and the machining platform is a cutting platform, which is used for cutting the electric core.

[0073] Refer to Figure 1 and Figure 3 As shown in the figure, it can be understood that in this embodiment, specifically, in step S200, the moving axis calibration and machining method can change the starting position of the calibration block, so as to obtain multiple groups of the first coordinates of the marked points on the calibration block in the 3D pixel coordinate system and the second coordinates in the 2D pixel coordinate system. Through the acquisition of multiple groups of the first coordinates and the second coordinates, sufficient data support can be obtained, which is conducive to improving the accuracy of the second transformation matrix, thereby improving the accuracy of welding guidance for the machining object.

[0074] Refer to Figure 1 and Figure 3 As shown in the figure, specifically, in step S200, the moving axis calibration and machining method can obtain nine groups of the first coordinates of the marked points on the calibration block in the 3D pixel coordinate system and the second coordinates in the 2D pixel coordinate system for constructing the second transformation matrix between the 3D pixel coordinate system and the 2D pixel coordinate system.

[0075] Refer to Figure 1 and Figure 3 As shown in the figure, it can be understood that in step S200, the moving axis calibration and machining method outputs the space trajectory data corresponding to the multi-axis space coordinate system according to the trajectory feature points combined with the first transformation matrix, and further includes the following steps:

[0076] Step S210: Obtain the trajectory coordinates of the trajectory feature points in the 2D pixel coordinate system according to the second transformation matrix. After optimizing the trajectory coordinates, output the spatial trajectory data corresponding to the optimized trajectory coordinates in combination with the first transformation matrix.

[0077] Refer to Figure 1 and Figure 3 As shown in

[0078] Refer to Figure 1 and Figure 3 As shown, after obtaining the trajectory feature points through the 3D camera, the moving axis calibration and machining method can use the second transformation matrix to transform the 3D pixel coordinate system of the trajectory feature points into the 2D pixel coordinate system, that is, obtain the trajectory coordinates. The moving axis calibration and machining method can use the 2D camera to actually capture the point coordinates of the shell wall of the corresponding trajectory feature points of the machining object. That is, the actual feature points and the trajectory feature points are extracted based on the same reference object on the machining object, so as to compare the actually captured point coordinates with the transformed coordinates of the trajectory feature points, thereby realizing the correction of errors to complete the optimization of the trajectory coordinates.

[0079] It can be understood that in step S100 of the moving axis calibration and machining method, controlling the multi-axis motion mechanism to drive the calibration ball to move along multiple moving axes includes the following steps:

[0080] Step S110: Set different multiple groups of starting points, and control the multi-axis motion mechanism to drive the calibration ball from the multiple groups of starting points respectively to calibrate the pose of the moving axis; in one calibration, the calibration ball moves a preset distance along multiple moving axes respectively.

[0081] Refer to Figure 1 and Figure 4 As shown in

[0082] Refer to Figure 1 and Figure 4As shown, specifically, in one calibration, the multi-axis motion mechanism can drive the calibration ball to start from a set starting point and move a preset distance along multiple moving axes respectively. That is, a preset movement amount is input into the original coordinates of the calibration ball, and the point cloud data generated by the movement of the calibration ball is obtained through a 3D camera to obtain multiple sets of transformation data for realizing the transformation between the multi-axis space coordinate system and the 3D pixel coordinate system, which is beneficial to improving the accuracy of the constructed first transformation matrix and reducing errors.

[0083] Referring to Figure 1 and Figure 5 As shown, it can be understood that the multi-axis motion mechanism includes three moving axes and two rotating axes. The three moving axes are the X-axis, Y-axis, and Z-axis respectively, and the two rotating axes are the A-axis and C-axis respectively.

[0084] Referring to Figure 1 and Figure 5 As shown, in the moving axis calibration and machining method, in step S110, the multi-axis motion mechanism is controlled to drive the calibration ball to calibrate the pose of the moving axis from multiple sets of starting points respectively; in one calibration, the calibration ball moves a preset distance along multiple moving axes respectively, including the following steps:

[0085] Step S111, perform multiple calibrations. In one calibration, the multi-axis motion mechanism drives the calibration ball to move a preset distance along the X-axis, Y-axis, and Z-axis respectively to obtain a point cloud map of the calibration ball. The point cloud data includes the point cloud map.

[0086] Referring to Figure 1 and Figure 5 As shown, specifically, the moving axis calibration and machining method can perform multiple calibrations on the pose of the moving axis through the calibration ball and the 3D camera. In one calibration, the multi-axis motion mechanism can drive the calibration ball to move a preset distance along the X-axis, Y-axis, and Z-axis respectively. That is, a preset movement amount is input into the center coordinates of the calibration ball along the X-axis, Y-axis, and Z-axis respectively. Under the scanning of the 3D camera, a point cloud map of the calibration ball can be obtained, and the point cloud map contains the point cloud coordinates of multiple spherical surfaces formed by the movement of the calibration ball.

[0087] Referring to Figure 1 and Figure 4 As shown, it can be understood that in step S100 of the moving axis calibration and machining method, the first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism is constructed according to the moving coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data, including the following steps:

[0088] Step S120, use the optimization search algorithm to reduce the error from the point cloud of the calibration ball to the center of the ball, and solve the direction vectors corresponding to multiple moving axes, indicating the installation deviation of the moving axes;

[0089] Step S130: Optimize the first transformation matrix according to the direction vector.

[0090] Refer to Figure 1 and Figure 4 As shown in

[0091] Refer to Figure 1 and Figure 4 In step S130, the moving axis calibration and machining method can optimize the first transformation matrix according to the direction vectors of multiple moving axes obtained by the optimal search algorithm, which is beneficial to reducing the error between the trajectory feature points and the spatial trajectory data conversion and improving the welding accuracy of the machining object.

[0092] Refer to Figure 1 and Figure 5 As shown in

[0093] Step S121: According to multiple point cloud maps, adopt a non - linear optimization method to reduce the error between the point cloud of the calibration sphere and its center, and solve the direction vectors of the X - axis, Y - axis, and Z - axis. The optimal search algorithm is a non - linear optimization method.

[0094] Refer to Figure 1 and Figure 5 As shown in

[0095] Refer to Figure 1 and Figure 2 It can be understood that specifically, in step S120, the moving axis calibration and machining method adopts an optimal search algorithm to reduce the error between the point cloud of the calibration sphere and its center, and solve the direction vectors corresponding to multiple moving axes. It further includes the following steps:

[0096] Step S122, the optimization search algorithm is calculated using the following objective function:

[0097]

[0098] Wherein, V x is the direction vector of the X-axis, V y is the direction vector of the Y-axis, V z is the direction vector of the Z-axis, P c is the center coordinate of the calibration sphere in the multi-axis space coordinate system, R is the standard radius of the calibration sphere, ΔT i is a set of measurement points (u i , v i ) on the spherical surface of the calibration sphere corresponding to the movement amount, M Δ is the transformation matrix of the movement amount.

[0099] Referring to Figure 1 and Figure 2 shown, when the movement direction of the displacement axis used for calculation is consistent with the actual direction, the distance from the three-dimensional coordinates of the spherical surface of the reconstructed calibration sphere to the actual center coordinate of the sphere should be equal to the standard radius R of the calibration sphere. Based on this concept, this moving axis calibration and machining method uses an optimization search method to search for the optimal V x , V y , V z and P c .

[0100] Referring to Figure 1 and Figure 2 shown, that is, this moving axis calibration and machining method converts the movement amount ΔT i into the displacement M Δ in the multi-axis space coordinate system through M Δ ΔT i , combines the measurement point [0 v i -u i T with the displacement M Δ ΔT i to obtain the position of this point after movement in the multi-axis space coordinate system, calculates the difference between the distance from this point to the center of the sphere and the standard radius R of the calibration sphere, and squares and accumulates the errors of all points. If there is a deviation in the installation of the moving axis, the optimized V x , V y and V z can directly reflect the direction of the actual axis.

[0101] Referring to Figure 1 and Figure 2 shown, it can be understood that this moving axis calibration and machining method includes the following steps in step S130:

[0102] ​In a multi-axis space coordinate system, let the direction vector of the X-axis be V x =(v xx ,v xy ,v xz ) T , the direction vector of the Y-axis be V y =(v yx ,v yy ,v yz ) T , and the direction vector of the Z-axis be V z =(v zx ,v zy ,v zz ) T ; Let the point (x, y, z) in the multi-axis space coordinate system move by ΔT = (Δx, Δy, -Δz) T along the X-axis, Y-axis, and Z-axis, and its coordinates in the 3D pixel coordinate system are (u, v);

[0103] The first transformation matrix is obtained as

[0104] where M Δ is the transformation matrix of the movement amount and is transformed using the following expression:

[0105]

[0106] Referring to Figure 1 and Figure 2 shown, this moving axis calibration and machining method can optimize the first transformation matrix by obtaining the direction vectors of the X-axis, Y-axis, and Z-axis through an optimization search algorithm, which is beneficial to reducing the error generated when converting trajectory feature points into spatial trajectory data, improving the accuracy of welding guidance for the machining object, and thus improving the welding quality of the machining object.

[0107] In addition, considering the influence of factors such as the rotation of the measurement points of the calibration ball around the rotation axis and specific coefficients, the transformation of the measurement points between the multi-axis space coordinate system and the 3D pixel coordinate system can be achieved using the following formula:

[0108]

[0109] where α can be used to represent the rotation matrix, specific coefficients, etc.

[0110] Referring to Figure 1 and Figure 2 shown, and this moving axis calibration and machining method can perform automatic calibration through vision software and programs, in cooperation with the machining platform, which is beneficial to reducing the cumbersome process of manual calibration, reducing the error caused by manual calibration, and thus improving the efficiency of welding the machining object.

[0111] Referring toFigure 1 and Figure 2 As shown, a processing platform according to an embodiment of the present invention includes a 3D camera and a multi-axis motion mechanism, and is used to implement the moving axis calibration and processing method of any one of the above embodiments. After the user places the calibration ball on the multi-axis motion mechanism, the moving axis calibration and processing method can control the multi-axis motion mechanism to drive the calibration ball to move along multiple moving axes, and control the 3D camera to obtain the point cloud data generated by the movement of the calibration ball. According to the moving coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data, a first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism is constructed, that is, the pose of the moving axis of the multi-axis motion mechanism is calibrated by the calibration ball and the 3D camera, so as to obtain the first transformation matrix, which is beneficial to improving the mapping accuracy between the 3D pixel coordinate system and the multi-axis space coordinate system. The moving axis calibration and processing method can control the 3D camera to scan the processing object to obtain the height map of the processing object scan, extract multiple trajectory feature points according to the height map, and output the space trajectory data corresponding to the multi-axis space coordinate system according to the trajectory feature points and the first transformation matrix. The moving axis calibration and processing method can control the processing platform to perform welding guidance on the processing object according to the space trajectory data to realize the forming surface shape of the processing object. The moving axis calibration and processing method calibrates the moving axis of the multi-axis motion mechanism through the calibration ball and the 3D camera, which is beneficial to reducing the error of the conversion between the trajectory feature points and the space trajectory data and improving the welding accuracy of the processing object.

[0112] Referring to Figure 1 and Figure 2As shown in the figure, a computer-readable storage medium according to an embodiment of the present invention stores computer-executable instructions, and the computer-executable instructions are used to cause a computer to execute the moving axis calibration and machining method as described in any one of the above. After the user places the calibration ball on the multi-axis motion mechanism, the moving axis calibration and machining method can control the multi-axis motion mechanism to drive the calibration ball to move along multiple moving axes, and control the 3D camera to obtain the point cloud data generated by the movement of the calibration ball. According to the moving coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data, a first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism is constructed, that is, the pose of the moving axis of the multi-axis motion mechanism is calibrated by the calibration ball and the 3D camera, so as to obtain the first transformation matrix, which is beneficial to improving the mapping accuracy between the 3D pixel coordinate system and the multi-axis space coordinate system. The moving axis calibration and machining method can control the 3D camera to scan the machining object to obtain the height map of the machining object scan, extract multiple trajectory feature points according to the height map, and output the space trajectory data corresponding to the multi-axis space coordinate system according to the trajectory feature points combined with the first transformation matrix. The moving axis calibration and machining method can control the machining platform to perform welding guidance on the machining object according to the space trajectory data to realize the shape of the formed surface of the machining object. The moving axis calibration and machining method calibrates the moving axis of the multi-axis motion mechanism through the calibration ball and the 3D camera, which is beneficial to reducing the error of the conversion between the trajectory feature points and the space trajectory data and improving the welding accuracy of the machining object.

[0113] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0114] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for realizing the functions specified in one Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0115] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a particular manner, such that the instructions stored in the computer-readable memory produce a manufacture including an instruction device that implements the functions specified in one or more of the processes Figure 1 one or more processes and / or blocks Figure 1 and / or blocks specified in one or more of the blocks.

[0116] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operational steps are performed on the computer or other programmable device to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more of the processes Figure 1 one or more processes and / or blocks Figure 1 and / or blocks specified in one or more of the blocks.

[0117] An embodiment of the present invention also provides a welding device, including a memory, a processor, and a program stored on the memory and executable on the processor. When the program is executed by the processor, it implements the mobile axis calibration and processing methods of the above embodiments.

[0118] Taking the example that the processor and the memory in the controller can be connected by a bus. The memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. In addition, the memory can include high-speed random access memory, and can also include non-transitory memory, such as at least one disk memory, flash memory device, or other non-transitory solid-state storage devices. In some embodiments, the memory can optionally include a memory remotely set relative to the control processor, and these remote memories can be connected to the control device through a network.

[0119] The non-transitory software programs and instructions required to implement the mobile axis calibration and processing methods of the above embodiments are stored in the memory. When executed by the processor, they perform the mobile axis calibration and processing methods in the above embodiments. For example, execute Figure 2 method steps S100 to step S300 in Figure 3 method steps S400 to step S210 in Figure 4 method steps S110 to step S130 in Figure 5 method steps S111 to step S121 in, etc.

[0120] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, that is, they may be located in one place, or may be distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0121] In addition, an embodiment of the present invention further provides a computer-readable storage medium storing computer-executable instructions for executing the above-mentioned moving axis calibration and machining method. Exemplarily, it executes the method steps described above Figures 2 to 5 in the above.

[0122] It should be noted that since the computer-readable storage medium of the embodiment of the present invention can execute the moving axis calibration and machining method of any of the above embodiments, the specific implementation manners and technical effects of the computer-readable storage medium of the embodiment of the present invention can refer to the specific implementation manners and technical effects of the moving axis calibration and machining method of any of the above embodiments.

[0123] In addition, an embodiment of the present invention further provides a computer program product including a computer program or computer instructions. The computer program or computer instructions are stored in a computer-readable storage medium. A processor of a computer device reads the computer program or computer instructions from the computer-readable storage medium, and the processor executes the computer program or computer instructions to enable the computer device to execute the above-mentioned moving axis calibration and machining method. Exemplarily, it executes the method steps described above Figures 2 to 5 in the above.

[0124] It should be noted that since the computer program product of the embodiment of the present invention can execute the moving axis calibration and machining method of any of the above embodiments, the specific implementation manners and technical effects of the computer program product of the embodiment of the present invention can refer to the specific implementation manners and technical effects of the moving axis calibration and machining method of any of the above embodiments.

[0125] Those of ordinary skill in the art will understand that all or some of the steps and systems disclosed in the above methods can be implemented as software, firmware, hardware, and their appropriate combinations. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include a computer storage medium (or non-transitory medium) and a communication medium (or transitory medium). As is well known to those of ordinary skill in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, tapes, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and that can be accessed by a computer. In addition, it is well known to those of ordinary skill in the art that communication media typically includes computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transmission mechanism, and can include any information delivery media.

[0126] The embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A mobile axis calibration and machining method, applied to a machining platform with a 3D camera and a multi-axis motion mechanism, characterized in that The method for calibrating and machining the moving axes includes: Controlling the multi-axis motion mechanism to drive the calibration ball to move along multiple moving axes, and controlling the 3D camera to acquire the point cloud data generated by the movement of the calibration ball. Construct a first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism according to the moving coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data; Controlling the 3D camera to acquire the height map of the machined object scanned, extracting multiple trajectory feature points according to the height map, and outputting the space trajectory data corresponding to the multi-axis space coordinate system according to the trajectory feature points in combination with the first transformation matrix; Controlling the machining platform to machine the machined object according to the space trajectory data.

2. The mobile shaft calibration and machining method according to claim 1, characterized in that: The machining platform further includes a 2D camera, and the 2D camera applies a 2D pixel coordinate system; The method for calibrating and machining the moving axes further includes: constructing a second transformation matrix from the 3D pixel coordinate system to the 2D pixel coordinate system according to the first transformation matrix, the first coordinates of the marked points on the calibration block in the 3D pixel coordinate system, and the second coordinates in the 2D pixel coordinate system; The outputting the space trajectory data corresponding to the multi-axis space coordinate system according to the trajectory feature points in combination with the first transformation matrix includes: obtaining the trajectory coordinates of the trajectory feature points in the 2D pixel coordinate system according to the second transformation matrix, optimizing the trajectory coordinates, and outputting the space trajectory data corresponding to the optimized trajectory coordinates in combination with the first transformation matrix.

3. The mobile axis calibration and machining method according to claim 1, characterized in that: The controlling the multi-axis motion mechanism to drive the calibration ball to move along multiple moving axes includes: Setting different multiple groups of starting points, and controlling the multi-axis motion mechanism to drive the calibration ball from multiple groups of the starting points to calibrate the poses of the moving axes respectively; in one calibration, the calibration ball moves a preset distance along multiple moving axes respectively.

4. The mobile axis calibration and machining method according to claim 3, characterized in that: The multiple moving axes are the X-axis, Y-axis, and Z-axis respectively; The controlling the multi-axis motion mechanism to drive the calibration ball from multiple groups of the starting points to calibrate the poses of the moving axes respectively; In one calibration, the calibration ball moves a preset distance along multiple moving axes respectively, including: Performing multiple calibrations. In one calibration, the multi-axis motion mechanism drives the calibration ball to move the preset distance along the X-axis, Y-axis, and Z-axis respectively to obtain a point cloud map of the calibration ball, and the point cloud data includes the point cloud map.

5. The mobile axis calibration and machining method according to claim 4, characterized in that: The constructing the first transformation matrix from the 3D pixel coordinate system of the 3D camera to the multi-axis space coordinate system of the multi-axis motion mechanism according to the moving coordinates of the calibration ball driven by the multi-axis motion mechanism and the point cloud data includes: Adopting an optimization search algorithm to reduce the error between the point cloud of the calibration ball and the ball center, and solving the direction vectors corresponding to multiple moving axes, representing the installation deviation of the moving axes; Optimizing the first transformation matrix according to the direction vectors.

6. The mobile axis calibration and machining method according to claim 5, characterized in that: The adopting an optimization search algorithm to reduce the error between the point cloud of the calibration ball and the ball center, and solving the direction vectors corresponding to multiple moving axes includes: Based on multiple said point cloud maps, a non - linear optimization method is used to reduce the error from the point cloud of the calibration sphere to the sphere center, and the direction vectors of the X - axis, Y - axis, and Z - axis are solved. The optimization search algorithm is the non - linear optimization method.

7. The mobile axis calibration and machining method according to claim 5, characterized in that: Using the optimization search algorithm to reduce the error from the point cloud of the calibration sphere to the sphere center and solve the direction vectors corresponding to multiple said moving axes, including: The optimization search algorithm is calculated using the following objective function: Among them, V x is the direction vector of the X-axis, V y is the direction vector of the Y-axis, V z is the direction vector of the Z-axis, P c is the spherical center coordinate of the calibration sphere in the multi-axis space coordinate system, R is the standard radius of the calibration sphere, ΔT i is a set of measurement points (u i , v i ) on the spherical surface of the calibration sphere corresponding to the movement amount, M Δ is the transformation matrix of the movement amount.

8. The mobile axis calibration and machining method according to claim 7, characterized in that: Optimizing the first transformation matrix according to the direction vector, including: In the multi-axis spatial coordinate system, let the direction vector of the X-axis be V x =(v xx , v xy , v xz ) T , the direction vector of the Y-axis be V y =(v yx , v yy , v yz ) T , and the direction vector of the Z-axis be V z =(v zx , v zy , v zz ) T ; Let the point (x, y, z) in the multi-axis spatial coordinate system move by ΔT = (Δx, Δy, -Δz) T along the X-axis, Y-axis, and Z-axis, and its coordinates in the 3D pixel coordinate system are (u, v); The first transformation matrix obtained is where M Δ is the transformation matrix of the movement amount and is transformed using the following expression:

9. The mobile axis calibration and machining method according to claim 2, characterized in that: The processing object is an electric core, the processing platform is a welding platform, the welding platform is used for welding the electric core, the welding platform further includes a galvanometer of a welding laser, and both the galvanometer and the 2D camera apply the 2D pixel coordinate system; Or, the processing object is an electric core, the processing platform is a dispensing platform, and the dispensing platform is used for dispensing the electric core; Or, the processing object is an electric core, the processing platform is a cutting platform, and the cutting platform is used for cutting the electric core.

10. Processing platform, characterized in that, Including: A 3D camera and a multi - axis motion mechanism, which are used to implement the moving axis calibration and processing method according to any one of claims 1 to 9.

11. A computer-readable storage medium, characterized in that, The computer - readable storage medium stores computer - executable instructions, and the computer - executable instructions are used to cause a computer to execute the moving axis calibration and processing method according to any one of claims 1 to 9.

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