Five-axis machine tool inspection method and device, computer equipment, readable storage medium and program product

Abstract

The invention relates to a five-axis machine tool inspection method and device, computer equipment, a computer readable storage medium and a computer program product. The method comprises the following steps: acquiring a first contour coordinate of a standard sphere under a machine tool coordinate system of a five-axis machine tool; the standard ball body is clamped by the five-axis machine tool; based on the first contour coordinate, determining a sphere center coordinate of the standard sphere in a machine tool coordinate system; aiming at each rotating shaft included in the five-axis machine tool, rotating the rotating shaft, and determining a circle center coordinate of a sphere center rotating path of the standard sphere in the rotating process of the rotating shaft; and determining an inspection result of the five-axis machine tool according to a coordinate difference value between the sphere center coordinate and each circle center coordinate. By adopting the method, the processing accuracy can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of workpiece processing, and in particular to a five-axis machine tool inspection method, device, computer equipment, computer-readable storage medium and computer program product. Background Art

[0002] With the development of workpiece processing technology, a key equipment, the five-axis machine tool, has emerged. The workpiece can be fixed on a fixture and processed by a five-axis machine tool through a fixed processing trajectory to improve the workpiece processing efficiency.

[0003] In traditional technology, when a five-axis machine tool clamps a workpiece during machining, there may be clamping errors, which will affect the machining process of the workpiece and result in low machining accuracy. Summary of the invention

[0004] Based on this, it is necessary to provide a five-axis machine tool inspection method, device, computer equipment, computer-readable storage medium and computer program product that can improve machining accuracy in response to the above technical problems.

[0005] In a first aspect, the present application provides a five-axis machine tool inspection method, comprising:

[0006] Acquiring the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool; the standard sphere is clamped by the five-axis machine tool;

[0007] Based on the first contour coordinates, determining the center coordinates of the standard sphere in the machine tool coordinate system;

[0008] For each rotation axis included in the five-axis machine tool, rotate the rotation axis to determine the center coordinates of the rotation path of the center of the standard sphere during the rotation of the rotation axis;

[0009] The inspection result of the five-axis machine tool is determined according to the coordinate differences between the spherical center coordinates and the circle center coordinates.

[0010] In one embodiment, obtaining the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool includes:

[0011] Get the second contour coordinates of the standard sphere in the camera coordinate system;

[0012] Based on the association relationship between the machine tool coordinate system of the five-axis machine tool and the camera coordinate system, the second contour coordinates are transformed to obtain the first contour coordinates of the standard sphere in the machine tool coordinate system.

[0013] In one embodiment, the method further comprises:

[0014] When at least one of the coordinate differences does not satisfy the difference condition, adjusting at least one coordinate axis in the machine tool coordinate system;

[0015] Return to the step of obtaining the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool, until the coordinate differences between the machine tool sphere center coordinates and the circle center coordinates all meet the difference conditions.

[0016] In one embodiment, the method further comprises:

[0017] For each to-be-processed point on the to-be-processed workpiece, determining an initial processing direction of the to-be-processed point and a laser direction of a laser emitted by a scanning camera;

[0018] When the initial processing direction is not perpendicular to the laser direction, the five-axis machine tool is controlled to clamp the workpiece to be processed and rotate until the updated processing direction of the point to be processed is perpendicular to the laser direction;

[0019] The rotation angle of the five-axis machine tool is used as the first rotation axis coordinate of the point to be processed; wherein the first rotation axis coordinate is used to instruct the five-axis machine tool to rotate the point to be processed according to the first rotation axis coordinate and then be scanned by the scanning camera.

[0020] In one embodiment, the method further comprises:

[0021] For each of the to-be-processed points, determining an initial normal vector of the to-be-processed point after the to-be-processed point is rotated according to the coordinates of the first rotation axis;

[0022] When the angle condition is not satisfied between the initial normal vector and the direction axis, the five-axis machine tool is controlled to clamp the workpiece to be processed and rotate until the angle condition is satisfied between the updated normal vector of the point to be processed and the direction axis;

[0023] The rotation angle of the five-axis machine tool is used as the second rotation axis coordinate of the point to be processed; wherein the second rotation axis coordinate is used to instruct the five-axis machine tool to rotate the processing point according to the second rotation axis coordinate and then process the point to be processed.

[0024] In one embodiment, the method further comprises:

[0025] Moving the five-axis machine tool to a calibration plate to determine the position coordinates of the five-axis machine tool;

[0026] Scanning the calibration plate by the scanning camera to determine the calibration plate coordinates of the calibration plate during the scanning process of the scanning camera;

[0027] Coordinate analysis is performed based on the posture coordinates and the calibration plate coordinates to determine the association relationship between the machine tool coordinate system of the five-axis machine tool and the camera coordinate system.

[0028] In a second aspect, the present application also provides a five-axis machine tool inspection device, comprising:

[0029] A first contour coordinate acquisition module, used to acquire first contour coordinates of a standard sphere in a machine tool coordinate system of a five-axis machine tool; the standard sphere is clamped by the five-axis machine tool;

[0030] A spherical center coordinate determination module, used for determining the spherical center coordinate of the standard sphere in the machine tool coordinate system based on the first contour coordinate;

[0031] A circle center coordinate determination module, for rotating each rotation axis included in the five-axis machine tool, and determining the circle center coordinate of the rotation path of the center of the standard sphere during the rotation of the rotation axis;

[0032] The inspection result determination module is used to determine the inspection result of the five-axis machine tool according to the coordinate differences between the spherical center coordinates and the circle center coordinates.

[0033] In a third aspect, the present application further provides a computer device, wherein the computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the above method are implemented.

[0034] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0035] In a fifth aspect, the present application further provides a computer program product, wherein the computer program product comprises a computer program, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0036] The above-mentioned five-axis machine tool inspection method, device, computer equipment, computer-readable storage medium and computer program product obtain the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool, which can determine the contour information of the standard sphere when clamped by the five-axis machine tool, and determine the center coordinates of the standard sphere in the machine tool coordinate system based on the first contour coordinates. For each rotation axis included in the five-axis machine tool, the rotation axis is rotated to determine the center coordinates of the rotation path of the center of the standard sphere during the rotation of the rotation axis, and the five-axis center coordinates are determined according to the coordinate differences between the center coordinates of the sphere and the center coordinates of each circle. The inspection result of the five-axis machine tool is that the change of the direction axis in the five-axis machine tool will affect the change of the rotation axis, and under standard circumstances, the rotation path of the center of the standard sphere after the rotation axis is rotated is a circle, that is, if there is a certain error in the direction axis of the five-axis machine tool, then the rotation path of the center of the standard sphere after the rotation axis is rotated will not be a circle, for example, it may be an ellipse. Therefore, the inspection result of the five-axis machine tool can be determined according to the coordinate difference between the center coordinates of the sphere and the center coordinates of each circle, thereby improving the accuracy of the five-axis machine tool inspection, and then improving the accuracy of the five-axis machine tool in processing the workpiece to be processed. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the drawings required for use in the embodiments of the present application or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 is an application environment diagram of a five-axis machine tool inspection method in one embodiment;

[0039] Figure 2 A schematic diagram of a flow chart of a five-axis machine tool inspection method in one embodiment;

[0040] Figure 3 A schematic diagram of a five-axis machine tool inspection step in one embodiment;

[0041] Figure 4 is a schematic diagram of an orthogonal five-axis machine tool in one embodiment;

[0042] Figure 5 is a schematic diagram of a non-orthogonal five-axis machine tool in one embodiment;

[0043] Figure 6 A schematic diagram of the formation of a fitting circle during the inspection process of a five-axis machine tool in one embodiment;

[0044] Figure 7 A schematic diagram of a flow chart of a five-axis machine tool inspection step in another embodiment;

[0045] Figure 8 A schematic diagram of a flow chart of a five-axis machine tool inspection method in yet another embodiment;

[0046] Fig. 9 is a structural block diagram of a five-axis machine tool inspection device in one embodiment;

[0047] Fig.10 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0049] The five-axis machine tool inspection method provided in the embodiment of the present application can be applied to Figure 1 In the application environment shown. Among them, the terminal 102 communicates with the five-axis machine tool 104 through the network. Among them, the terminal 102 can be but not limited to various personal computers, laptops, smart phones, tablets, Internet of Things devices and portable wearable devices. The Internet of Things devices can be smart speakers, smart TVs, smart air conditioners, smart car devices, projection devices, etc. Portable wearable devices can be smart watches, smart bracelets, head-mounted devices, etc. The head-mounted devices can be virtual reality (VR) devices, augmented reality (AR) devices, smart glasses, etc. The five-axis machine tool 104 is a mode of CNC machine tool processing. It adopts linear interpolation motion of any five coordinates of X, Y, Z, A, B, and C. Through the combined motion of these five coordinate axes, high-precision processing of complex surfaces is achieved. Specifically, during the five-axis machine tool inspection, the terminal obtains the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool 104; the standard sphere is clamped by the five-axis machine tool 104; based on the first contour coordinates, the center coordinates of the standard sphere in the machine tool coordinate system are determined; for each rotation axis included in the five-axis machine tool 104, the rotation axis is rotated to determine the center coordinates of the rotation path of the center of the standard sphere during the rotation of the rotation axis; according to the coordinate differences between the center coordinates of the sphere and each center coordinate, the inspection result of the five-axis machine tool 104 is determined.

[0050] In an exemplary embodiment, Figure 2 As shown, a five-axis machine tool inspection method is provided, which is applied to Figure 1 The terminal 102 in the example is used as an example to illustrate, including the following steps S202 to S208. Among them:

[0051] Step S202, obtaining the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool.

[0052] Among them, the standard sphere is clamped by the five-axis machine tool. The standard ball refers to a sphere that meets certain standards or specifications, such as a specific diameter, mass, shape, etc., which can be used for five-axis machine tool calibration. The five-axis machine tool is a mode of CNC machine tool processing. It adopts linear interpolation motion of any five coordinates of X, Y, Z, A, B, and C. Through the combined motion of these five coordinate axes, high-precision processing of complex surfaces is achieved. The machine tool coordinate system is specified by the machine tool manufacturer and is a reference system used to describe machine tool motion, workpiece positioning, and tool path. It usually takes the machine tool origin O as the origin of the coordinate system and follows the principle of the right-handed Cartesian rectangular coordinate system. The first contour coordinate refers to the contour coordinate of the standard sphere in the machine tool coordinate system of the five-axis machine tool. It can be understood that the first contour coordinate includes multiple sub-coordinates, which can be used to characterize the three-dimensional data of the standard sphere in the machine tool coordinate system of the five-axis machine tool.

[0053] Specifically, in order to inspect the five-axis machine tool, the terminal can first obtain the first contour coordinates of the standard sphere in the machine coordinate system of the five-axis machine tool, and then determine the three-dimensional data of the standard sphere in the machine coordinate system of the five-axis machine tool. Exemplarily, the operation of obtaining the first contour coordinates of the standard sphere in the machine coordinate system of the five-axis machine tool can be active acquisition or passive reception. It can be understood that the first contour coordinates of the standard sphere in the machine coordinate system of the five-axis machine tool may not be directly obtained. Therefore, in some specific embodiments, the standard sphere can be laser scanned by a scanning camera to determine the second contour coordinates of the standard sphere in the camera coordinate system, and then the coordinate conversion is performed according to the second contour coordinates to obtain the first contour coordinates of the standard sphere in the machine coordinate system of the five-axis machine tool.

[0054] Step S204: determining the center coordinates of the standard sphere in the machine tool coordinate system based on the first contour coordinates.

[0055] The spherical center coordinates refer to the coordinates of the center of the standard sphere in the airport coordinate system.

[0056] Specifically, after obtaining the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool, the terminal can perform fitting according to the first contour coordinates to determine the center coordinates of the standard sphere in the machine tool coordinate system.

[0057] Step S206: for each rotation axis included in the five-axis machine tool, rotate the rotation axis to determine the center coordinates of the rotation path of the center of the standard sphere during the rotation of the rotation axis.

[0058] Among them, the rotation axis refers to the axis that can rotate the workpiece during the machining process. In a five-axis machine tool, the rotation axis is usually composed of two additional rotation coordinate axes, which can provide additional rotational degrees of freedom on the basis of the three linear coordinate axes of X, Y, and Z. The center rotation path refers to the path formed by the center of the standard sphere during the rotation of the rotation axis. In this embodiment, the path formed by the center of the standard sphere during the rotation of the rotation axis is elliptical or circular. The center coordinates refer to the coordinates of the center of the circle in the elliptical path or circular path.

[0059] Specifically, since the change of the direction axis in the five-axis machine tool will affect the change of the rotation axis, and under standard circumstances, the rotation path of the center of the standard sphere after the rotation axis is rotated is a circle, that is, if there is a certain error in the direction axis of the five-axis machine tool, then the rotation path of the center of the standard sphere after the rotation axis is rotated will not be a circle, for example, it may be an ellipse. Therefore, for each rotation axis included in the five-axis machine tool, the rotation axis can be rotated to determine the center coordinates of the rotation path of the center of the standard sphere during the rotation of the rotation axis, so as to determine the inspection result of the five-axis machine tool based on the coordinate difference between the center coordinates of the circle and the center coordinates of the sphere.

[0060] Step S208, determining the inspection result of the five-axis machine tool according to the coordinate differences between the sphere center coordinates and the circle center coordinates.

[0061] Among them, the inspection results can indicate whether the five-axis machine tool meets the standards.

[0062] Specifically, following the previous step, after determining the center coordinates of the rotation path of the center of the standard sphere during the rotation of the rotation axis, the terminal can determine the inspection result of the five-axis machine tool based on the coordinate differences between the center coordinates of the sphere and the coordinates of the centers of each circle. For example, if the coordinate differences between the center coordinates of the sphere and the coordinates of the centers of each circle meet the difference conditions, it indicates that the inspection result of the five-axis machine tool is qualified. If at least one of the coordinate differences between the center coordinates of the sphere and the coordinates of the centers of each circle does not meet the difference conditions, it indicates that the inspection result of the five-axis machine tool is unqualified.

[0063] The above-mentioned five-axis machine tool inspection method obtains the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool, and can determine the contour information of the standard sphere when clamped by the five-axis machine tool. Based on the first contour coordinates, the center coordinates of the standard sphere in the machine tool coordinate system are determined. For each rotating axis included in the five-axis machine tool, the rotating axis is rotated to determine the center coordinates of the rotation path of the center of the standard sphere during the rotation of the rotating axis. According to the coordinate differences between the center coordinates and the coordinates of each circle center, the inspection result of the five-axis machine tool is determined. Since the change of the direction axis in the five-axis machine tool will affect the change of the rotating axis, and under standard circumstances, the rotation path of the center of the standard sphere after the rotating axis is rotated is a circle, that is, if there is a certain error in the direction axis of the five-axis machine tool, then the rotation path of the center of the standard sphere after the rotating axis is rotated will not be a circle, for example, it may be an ellipse. Therefore, the inspection result of the five-axis machine tool can be determined according to the coordinate differences between the center coordinates and the coordinates of each circle center, thereby improving the accuracy of the five-axis machine tool inspection, and then improving the accuracy of the five-axis machine tool in processing the workpiece to be processed.

[0064] In an exemplary embodiment, obtaining the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool includes: obtaining the second contour coordinates of the standard sphere in the camera coordinate system; based on the association relationship between the machine tool coordinate system of the five-axis machine tool and the camera coordinate system, converting the second contour coordinates to obtain the first contour coordinates of the standard sphere in the machine tool coordinate system.

[0065] The camera coordinate system is a three-dimensional rectangular coordinate system with the focal center (i.e., optical center) of the camera as the origin and the optical axis as the Z axis. In this embodiment, the camera coordinate system refers to the coordinate system in the scanning camera, and the scanning camera can emit laser to scan the standard sphere. The second contour coordinate is the contour coordinate of the standard sphere in the camera coordinate system of the scanning camera.

[0066] Specifically, the association relationship between the machine tool coordinate system and the camera coordinate system of the five-axis machine tool can be obtained in advance, and then only the second contour coordinates of the standard sphere in the camera coordinate system need to be obtained. Based on the above association relationship, the second contour coordinates can be transformed to obtain the first contour coordinates of the standard sphere in the machine tool coordinate system.

[0067] In this embodiment, through the association relationship between the machine tool coordinate system of the five-axis machine tool and the camera coordinate system, the first contour coordinates can be calculated based on the second contour coordinates, thereby ensuring the accuracy of the first contour coordinates.

[0068] In an exemplary embodiment, the five-axis machine tool inspection method also includes: adjusting at least one coordinate axis in the machine tool coordinate system when at least one of the coordinate differences does not meet the difference condition; returning to the step of obtaining the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool until the coordinate differences between the machine tool sphere center coordinates and the center coordinates of each circle meet the difference condition.

[0069] The difference condition refers to a condition satisfied by the coordinate difference. In this embodiment, the difference condition refers to a preset circular radius.

[0070] Specifically, when at least one of the coordinate differences does not meet the difference condition, it indicates that the rotation path of the center of the sphere is not a circle, that is, there is a certain error in the five-axis machine tool. Therefore, at least one coordinate axis in the machine tool coordinate system needs to be adjusted; return to the step of returning to the first contour coordinate of the standard sphere in the machine tool coordinate system of the five-axis machine tool, and re-determine and judge the coordinate difference until the coordinate difference between the machine tool sphere center coordinate and the center coordinate of each circle meets the difference condition. At this time, the five-axis machine tool basically meets the inspection requirements.

[0071] In this embodiment, when at least one of the coordinate differences does not meet the difference condition, the coordinate axis is readjusted, so that the five-axis machine tool with errors can be finally adjusted to a five-axis machine tool that meets the inspection requirements, thereby improving the accuracy of the five-axis machine tool in processing the workpiece to be processed.

[0072] In an exemplary embodiment, the five-axis machine tool inspection method also includes: for each point to be processed on the workpiece to be processed, determining the initial processing direction of the point to be processed and the laser direction of the laser emitted by the scanning camera; when the initial processing direction is not perpendicular to the laser direction, controlling the five-axis machine tool to clamp the workpiece to be processed and rotate until the updated processing direction of the point to be processed is perpendicular to the laser direction; and using the rotation angle of the five-axis machine tool as the first rotation axis coordinate of the point to be processed.

[0073] The workpiece to be processed refers to the workpiece waiting to be processed. The point to be processed represents the specific location on the workpiece to be processed that needs to be processed or treated in some form. The initial processing direction of the point to be processed refers to the processing direction of the point to be processed in the initial state, which can be represented by a direction vector. The laser direction is the direction in which the laser is emitted, which can also be represented by a direction vector. The first rotation axis coordinate is used to indicate that the five-axis machine tool rotates the point to be processed according to the first rotation axis coordinate and is scanned by the scanning camera.

[0074] Specifically, since the scanning camera will project a laser line to the workpiece for measurement during the scanning process, the laser line needs to be perpendicular to the processed edge of the workpiece each time it is measured in order to obtain the specific three-dimensional coordinates of the processed edge of the workpiece. Therefore, it is necessary to generate a scanning trajectory based on the first contour coordinates of the workpiece and the processed edge. Figure 3 As shown in the figure, assuming that the direction vector of a point Q to be processed on the processing position of the workpiece to be processed is V0, and the direction vector of the laser line is L0, it is necessary to calculate the rotation angle (Ap, As) of the active axis P and the driven axis S of the five-axis machine tool so that VO⊥L0. And calculate the new position Q' after the Q point rotates by the angle (Ap, As), then the scanning position of the Q point is (xq', yq', zq', Ap, As), where (xq', yq', zq') is the machine tool coordinate of Q', and (Ap, As) is the coordinate of the first rotation axis. Then the scanning position set of all points on the edge of the workpiece is the scanning trajectory Mc.

[0075] In this embodiment, after the five-axis machine tool is inspected, it is necessary to adjust the position of the workpiece to be processed when the scanning camera is scanning to improve the scanning accuracy, thereby improving the processing accuracy of the workpiece to be processed.

[0076] In an exemplary embodiment, the five-axis machine tool inspection method also includes: for each point to be processed, determining the initial normal vector of the point to be processed after rotation according to the first rotation axis coordinate; when the initial normal vector and the direction axis do not meet the angle condition, controlling the five-axis machine tool to clamp the workpiece to be processed and rotate until the updated normal vector of the point to be processed and the direction axis meet the angle condition; and using the rotation angle of the five-axis machine tool as the second rotation axis coordinate of the point to be processed.

[0077] Among them, the second rotation axis coordinate is used to instruct the five-axis machine tool to rotate the processing point according to the second rotation axis coordinate before processing the processing point. The initial normal vector refers to the normal vector of the processing point in the initial state. The angle condition refers to the condition that the angle between the initial normal vector and the direction axis satisfies. In this embodiment, the angle condition refers to the angle between the initial normal vector and the Z direction axis being 0 or other preset angles.

[0078] Specifically, after determining the scanning trajectory, the terminal can determine, for each point to be processed, the initial normal vector of the point to be processed after being rotated according to the first rotation axis coordinate. When the angle condition is not met between the initial normal vector and the direction axis, it is also necessary to adjust the angle of the workpiece to be processed. Therefore, the five-axis machine tool is controlled to clamp the workpiece to be processed and rotate until the updated normal vector of the point to be processed and the direction axis meet the angle condition. The rotation angle of the five-axis machine tool is used as the second rotation axis coordinate of the point to be processed, thereby instructing the five-axis machine tool to rotate the point to be processed according to the second rotation axis coordinate and then process the point to be processed.

[0079] In this embodiment, after determining the scanning trajectory, it is also necessary to determine the processing trajectory of the point to be processed, so as to ensure the processing accuracy of the workpiece to be processed.

[0080] In an exemplary embodiment, the five-axis machine tool inspection method also includes: moving the five-axis machine tool to a calibration plate to determine the posture coordinates of the five-axis machine tool; scanning the calibration plate with a scanning camera to determine the calibration plate coordinates of the calibration plate during the scanning process of the scanning camera; performing coordinate analysis based on the posture coordinates and the calibration plate coordinates to determine the association relationship between the machine tool coordinate system and the camera coordinate system of the five-axis machine tool.

[0081] Among them, the calibration plate is a precision measurement tool used in the fields of machine vision, image measurement, photogrammetry and 3D reconstruction. It is one or more plane objects printed with specific patterns. The pose coordinates are the coordinates corresponding to the orientation and posture of the five-axis machine tool. It can be understood that the form of the calibration plate is not unique. You can use a calibration plate or some calibration objects with obvious features (the core is to construct the common control points between the five-axis machine tool and the camera), such as a calibration block with features such as cusps and corners.

[0082] Specifically, in order to determine the relationship between the machine tool coordinate system and the camera coordinate system of the five-axis machine tool, the coordinates of the five-axis machine tool and the scanning camera can be respectively measured on the same calibration plate, so as to perform coordinate analysis based on the pose coordinates and the calibration plate coordinates to determine the relationship between the machine tool coordinate system and the camera coordinate system of the five-axis machine tool. In some specific embodiments, the camera coordinate system and the machine tool coordinate system can be unified through the hand-eye calibration algorithm, as shown in the following formula:

[0083] Xm=Rcm*Xc+Tcm

[0084] Among them, Xm is the machine tool coordinate system, Xc is the camera coordinate system, Rcm and Tcm are the rotation and translation matrices (the transformation matrices obtained by the hand-eye calibration algorithm).

[0085] In this embodiment, the correlation relationship between the machine tool coordinate system of the five-axis machine tool and the camera coordinate system is determined by calibration, which can ensure the accuracy of the determination of the correlation relationship.

[0086] In a specific embodiment, a five-axis machine tool inspection method based on a line laser scanning 3D camera in an actual application scenario is also provided, using a line laser scanning 3D camera (scanning camera) and a standard ball (standard sphere) to calibrate the model parameters of a non-orthogonal five-axis machine tool;

[0087] In the ideal five-axis machine tool model: 1) ∠XOY = ∠XOZ = ∠YOZ = 90°; 2) O'A∥OX, O'C∥OA; 3) P and S (P is the active axis, S is the driven axis, P axis drives S axis to move - P axis corresponds to A and B axis, S axis corresponds to C axis) axes intersect at a point O' in space. Figure 4 shown.

[0088] Due to the manufacturing and assembly errors of five-axis machine tools, non-orthogonal five-axis models such as Figure 5 As shown: 1) ∠XOY, ∠XOZ, ∠YOZ ≠ 90°; 2) O'A is not parallel to OX, O'C is not parallel to OA; 3) AC axes do not intersect in space.

[0089] Calibration method: First, the line laser scanning 3D camera coordinate system and the five-axis machine tool coordinate system are unified through the hand-eye calibration algorithm. Among them, Xm is the machine tool coordinate system, Xc is the line laser scanning 3D camera coordinate system, and Rcm and Tcm are the rotation and translation matrices (the transformation matrices obtained by the hand-eye calibration algorithm).

[0090] Xm=Rcm*Xc+Tcm

[0091] Secondly, the linear axis of the five-axis is used to drive the linear laser scanning 3D camera to scan the standard ball. The camera coordinate system is converted to the machine tool coordinate system through the above formula, and the center of the ball is fitted.

[0092] The parameters that need to be solved are: 1) the spatial straight line equations of the S and P axes in the machine tool coordinate system; 2) the direction vectors of OX, OY and OZ in the machine tool coordinate system.

[0093] A line laser scanning 3D camera is used to scan the 3D point cloud data of the standard sphere surface. The 3D coordinates Bc of the center of the standard sphere are obtained by fitting.

[0094] The S and P axes rotate separately, so the standard ball forms a circle on a plane perpendicular to the S and P axes. Fitting the center of the circle and calculating the plane normal vector can obtain the spatial straight line equations of the S and P axes respectively. The straight line equations are as follows: (x0, y0, z0) is a point on the straight line, and (nx, ny, nz) is the straight line direction vector.

[0095]

[0096] Non-orthogonal five-axis machine tool model parameter solution process, OX, OY, OZ changes:

[0097] OX, OY, OZ represent the direction vectors of the five-axis machine tool linear axis X, Y, Z in the machine tool coordinate system. Theoretically, OX⊥OY⊥OZ, OX={1, 0, 0}, OY={0, 1, 0}, OZ={0, 0, 1}. Due to the manufacturing and assembly errors of the linear axis, they are not perpendicular to each other, OX={Xnx, Xny, Xnz}, OY={Ynx, Yny, Ynz}, OZ={Znx, Zny, Znz}.

[0098] When OX, OY, and OZ are perpendicular to each other, Figure 6 The trajectory of the ball center in is a standard circle. Assuming that the center of the fitting circle is Ob and the radius is Rb, the distance from any point P on the circle to Ob is Db, and Db=Rb; when OX, OY, and OZ are not perpendicular, Figure 6 The trajectory of the ball center in is an ellipse. After fitting the center, the fitting error E=|Db-Rb|. Therefore, modify the vector parameters of OX, OY, OZ (for example, modify Xnx, Xny, Xnz in OX), recalculate the coordinates of the ball center in the machine tool coordinate system, and then fit. The size of the fitting error E can be used to determine whether the optimal result is achieved.

[0099] During the scanning process, the scanning camera will project a laser line to the workpiece for measurement. Therefore, the laser line needs to be perpendicular to the processed edge of the workpiece each time it is measured in order to obtain the specific three-dimensional coordinates of the processed edge of the workpiece. Therefore, it is necessary to generate a scanning trajectory based on the first contour coordinates of the workpiece and the processed edge. Figure 3 As shown in the figure, assuming that the direction vector of a point Q to be processed on the processing position of the workpiece to be processed is V0, and the direction vector of the laser line is L0, it is necessary to calculate the rotation angle (Ap, As) of the active axis P and the driven axis S of the five-axis machine tool so that VO⊥L0. And calculate the new position Q' after the Q point rotates by the angle (Ap, As), then the scanning position of the Q point is (xq', yq', zq', Ap, As), where (xq', yq', zq') is the machine tool coordinate of Q', and (Ap, As) is the coordinate of the first rotation axis. Then the scanning position set of all points on the edge of the workpiece is the scanning trajectory Mc.

[0100] By scanning the trajectory, the three-dimensional coordinates of the processing position of the workpiece are measured to generate the processing trajectory. The workpiece is scanned according to the scanning trajectory Mc, and the three-dimensional coordinates of the processing position of the workpiece are obtained, which are recorded as Mm (xi, yi, zi, Api, Asi) i=0,1,2...... Assuming that the normal vector of any point Q on the workpiece is Vq, the normal vector Vq must be consistent with the Z-axis direction (or meet a specific angle) during processing. Therefore, the trajectory Mm needs to be planned again to solve the processing trajectory Mt.

[0101] Specifically, the above method includes:

[0102] Step S701, setting the direction vectors of OX, OY and OZ in the machine tool coordinate system;

[0103] Step S702, calculating the linear equations of the S and P axes space by circle fitting;

[0104] Step S703, whether the circle fitting error E is the smallest;

[0105] If not, return to step S702;

[0106] If yes, execute step S704 and end.

[0107] In a specific embodiment, Figure 8 As shown, a five-axis machine tool inspection method is also provided, comprising:

[0108] Step S801, moving the five-axis machine tool to the calibration plate to determine the position coordinates of the five-axis machine tool;

[0109] Step S802, scanning the calibration plate by a scanning camera to determine the calibration plate coordinates of the calibration plate during the scanning process of the scanning camera;

[0110] Step S803, performing coordinate analysis based on the pose coordinates and the calibration plate coordinates to determine the correlation between the machine tool coordinate system of the five-axis machine tool and the camera coordinate system;

[0111] Step S804, obtaining the second contour coordinates of the standard sphere in the camera coordinate system, and based on the association relationship between the machine tool coordinate system of the five-axis machine tool and the camera coordinate system, transforming the second contour coordinates to obtain the first contour coordinates of the standard sphere in the machine tool coordinate system;

[0112] Among them, the standard sphere is clamped by a five-axis machine tool;

[0113] Step S805, based on the first contour coordinates, determine the coordinates of the center of the standard sphere in the machine tool coordinate system, and for each rotation axis included in the five-axis machine tool, rotate the rotation axis to determine the coordinates of the center of the standard sphere during the rotation of the rotation axis.

[0114] Step S806, when at least one of the coordinate differences does not satisfy the difference condition, adjusting at least one coordinate axis in the machine tool coordinate system;

[0115] Step S807, returning to the step of obtaining the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool, until the coordinate differences between the machine tool sphere center coordinates and the center coordinates of each circle meet the difference conditions;

[0116] Step S808, for each to-be-processed point on the to-be-processed workpiece, determining an initial processing direction of the to-be-processed point and a laser direction of the laser emitted by the scanning camera;

[0117] Step S809, when the initial processing direction is not perpendicular to the laser direction, control the five-axis machine tool to clamp the workpiece to be processed and rotate until the updated processing direction of the point to be processed is perpendicular to the laser direction;

[0118] Step S810, using the rotation angle of the five-axis machine tool as the first rotation axis coordinate of the point to be processed;

[0119] The first rotation axis coordinate is used to instruct the five-axis machine tool to rotate the processing point according to the first rotation axis coordinate and then be scanned by the scanning camera;

[0120] Step S811, for each to-be-processed point, determining an initial normal vector of the to-be-processed point after rotation according to the first rotation axis coordinates;

[0121] Step S812, when the initial normal vector and the direction axis do not satisfy the angle condition, control the five-axis machine tool to clamp the workpiece to be processed and rotate until the updated normal vector of the point to be processed and the direction axis satisfy the angle condition;

[0122] Step S813, using the rotation angle of the five-axis machine tool as the second rotation axis coordinate of the point to be processed;

[0123] The second rotation axis coordinate is used to instruct the five-axis machine tool to rotate the processing point according to the second rotation axis coordinate and then process the processing point.

[0124] It should be understood that, although the steps in the flowcharts involved in the above embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0125] Based on the same inventive concept, the embodiment of the present application also provides a five-axis machine tool inspection device for implementing the five-axis machine tool inspection method involved above. The implementation solution provided by the device to solve the problem is similar to the implementation solution recorded in the above method, so the specific limitations in one or more five-axis machine tool inspection device embodiments provided below can refer to the limitations of the five-axis machine tool inspection method above, and will not be repeated here.

[0126] In an exemplary embodiment, Fig. 9 As shown, a five-axis machine tool inspection device 900 is provided, comprising: a first contour coordinate acquisition module 902, a spherical center coordinate determination module 904, a circle center coordinate determination module 906 and an inspection result determination module 908, wherein:

[0127] The first contour coordinate acquisition module 902 is used to acquire the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool; the standard sphere is clamped by the five-axis machine tool;

[0128] A sphere center coordinate determination module 904 is used to determine the sphere center coordinates of the standard sphere in the machine tool coordinate system based on the first contour coordinates;

[0129] The center coordinate determination module 906 is used to rotate the rotation axis for each rotation axis included in the five-axis machine tool, and determine the center coordinate of the rotation path of the center of the standard sphere during the rotation of the rotation axis;

[0130] The inspection result determination module 908 is used to determine the inspection result of the five-axis machine tool according to the coordinate differences between the sphere center coordinates and the circle center coordinates.

[0131] In an exemplary embodiment, the first contour coordinate acquisition module 902 is specifically used for:

[0132] Get the second contour coordinates of the standard sphere in the camera coordinate system;

[0133] Based on the association between the machine tool coordinate system of the five-axis machine tool and the camera coordinate system, the second contour coordinates are transformed to obtain the first contour coordinates of the standard sphere in the machine tool coordinate system.

[0134] In an exemplary embodiment, the five-axis machine tool inspection device 900 further includes a cycle adjustment module, which is specifically used to:

[0135] When at least one of the coordinate differences does not satisfy the difference condition, adjusting at least one coordinate axis in the machine tool coordinate system;

[0136] Return to the step of obtaining the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool, until the coordinate differences between the machine tool sphere center coordinates and the center coordinates of each circle meet the difference conditions.

[0137] In an exemplary embodiment, the five-axis machine tool inspection device 900 further includes a first rotation axis coordinate determination module, which is specifically used to:

[0138] For each to-be-processed point on the to-be-processed workpiece, determining an initial processing direction of the to-be-processed point and a laser direction of a laser emitted by a scanning camera;

[0139] When the initial processing direction is not perpendicular to the laser direction, the five-axis machine tool is controlled to clamp the workpiece to be processed and rotate until the updated processing direction of the point to be processed is perpendicular to the laser direction;

[0140] The rotation angle of the five-axis machine tool is used as the first rotation axis coordinate of the point to be processed; wherein the first rotation axis coordinate is used to instruct the five-axis machine tool to rotate the point to be processed according to the first rotation axis coordinate and then be scanned by the scanning camera.

[0141] In an exemplary embodiment, the five-axis machine tool inspection device 900 further includes a second rotation axis coordinate determination module, which is specifically used to: for each to-be-processed point, determine an initial normal vector of the to-be-processed point after rotation according to the first rotation axis coordinate;

[0142] When the initial normal vector and the direction axis do not meet the angle condition, the five-axis machine tool is controlled to clamp the workpiece to be processed and rotate until the updated normal vector of the point to be processed meets the angle condition with the direction axis;

[0143] The rotation angle of the five-axis machine tool is used as the second rotation axis coordinate of the point to be processed; wherein the second rotation axis coordinate is used to instruct the five-axis machine tool to rotate the processing point according to the second rotation axis coordinate and then process the point to be processed.

[0144] In an exemplary embodiment, the five-axis machine tool inspection device 900 further includes an association relationship determination module, which is specifically used to:

[0145] Move the five-axis machine tool to the calibration plate to determine the position coordinates of the five-axis machine tool;

[0146] Scanning the calibration plate with a scanning camera to determine the calibration plate coordinates of the calibration plate during the scanning process of the scanning camera;

[0147] Coordinate analysis is performed based on the pose coordinates and the calibration plate coordinates to determine the relationship between the machine tool coordinate system and the camera coordinate system of the five-axis machine tool.

[0148] Each module in the above-mentioned five-axis machine tool inspection device can be implemented in whole or in part by software, hardware and their combination. Each of the above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory in the computer device in the form of software, so that the processor can call and execute the corresponding operations of each of the above modules.

[0149] In an exemplary embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as shown in FIG. Fig.10 As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be realized through WIFI, a mobile cellular network, near field communication (NFC) or other technologies. When the computer program is executed by the processor, a five-axis machine tool inspection method is realized. The display unit of the computer device is used to form a visually visible picture, which can be a display screen, a projection device or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device shell, or an external keyboard, touchpad or mouse.

[0150] Those skilled in the art will understand that Fig.10 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0151] In one embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps of the above method when executing the computer program.

[0152] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0153] In one embodiment, a computer program product is provided, comprising a computer program, which implements the steps of the above method when executed by a processor.

[0154] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0155] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, an artificial intelligence (AI) processor, etc., but are not limited to this.

[0156] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0157] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A five-axis machine tool inspection method, characterized in that: The method comprises: Acquiring the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool; the standard sphere is clamped by the five-axis machine tool; Based on the first contour coordinates, determining the coordinates of the center of the standard sphere in the machine tool coordinate system; For each rotation axis included in the five-axis machine tool, rotate the rotation axis to determine the center coordinates of the rotation path of the center of the standard sphere during the rotation of the rotation axis; The inspection result of the five-axis machine tool is determined according to the coordinate differences between the spherical center coordinates and the circle center coordinates.

2. The method according to claim 1, characterized in that The step of obtaining the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool comprises: Get the second contour coordinates of the standard sphere in the camera coordinate system; Based on the association relationship between the machine tool coordinate system of the five-axis machine tool and the camera coordinate system, the second contour coordinates are transformed to obtain the first contour coordinates of the standard sphere in the machine tool coordinate system.

3. The method according to claim 1, characterized in that The method further comprises: When at least one of the coordinate differences does not satisfy the difference condition, adjusting at least one coordinate axis in the machine tool coordinate system; Return to the step of obtaining the first contour coordinates of the standard sphere in the machine tool coordinate system of the five-axis machine tool, until the coordinate differences between the machine tool sphere center coordinates and the circle center coordinates all meet the difference conditions.

4. The method according to claim 1, characterized in that: The method further comprises: For each to-be-processed point on the to-be-processed workpiece, determining an initial processing direction of the to-be-processed point and a laser direction of a laser emitted by a scanning camera; When the initial processing direction is not perpendicular to the laser direction, the five-axis machine tool is controlled to clamp the workpiece to be processed and rotate until the updated processing direction of the point to be processed is perpendicular to the laser direction; The rotation angle of the five-axis machine tool is used as the first rotation axis coordinate of the point to be processed; wherein the first rotation axis coordinate is used to instruct the five-axis machine tool to rotate the point to be processed according to the first rotation axis coordinate and then be scanned by the scanning camera.

5. The method according to claim 4, characterized in that The method further comprises: For each of the to-be-processed points, determining an initial normal vector of the to-be-processed point after the to-be-processed point is rotated according to the coordinates of the first rotation axis; When the angle condition is not satisfied between the initial normal vector and the direction axis, the five-axis machine tool is controlled to clamp the workpiece to be processed and rotate until the angle condition is satisfied between the updated normal vector of the point to be processed and the direction axis; The rotation angle of the five-axis machine tool is used as the second rotation axis coordinate of the point to be processed; wherein the second rotation axis coordinate is used to instruct the five-axis machine tool to rotate the processing point according to the second rotation axis coordinate and then process the point to be processed.

6. The method according to any one of claims 1 to 5, characterized in that The method further comprises: Moving the five-axis machine tool to a calibration plate to determine the position coordinates of the five-axis machine tool; Scanning the calibration plate by the scanning camera to determine the calibration plate coordinates of the calibration plate during the scanning process of the scanning camera; Coordinate analysis is performed based on the posture coordinates and the calibration plate coordinates to determine the association relationship between the machine tool coordinate system of the five-axis machine tool and the camera coordinate system.

7. A five-axis machine tool inspection device, characterized in that: The device comprises: A first contour coordinate acquisition module, used to acquire first contour coordinates of a standard sphere in a machine tool coordinate system of a five-axis machine tool; the standard sphere is clamped by the five-axis machine tool; A spherical center coordinate determination module, used for determining the spherical center coordinate of the standard sphere in the machine tool coordinate system based on the first contour coordinate; A circle center coordinate determination module, for rotating each rotation axis included in the five-axis machine tool, and determining the circle center coordinate of the rotation path of the center of the standard sphere during the rotation of the rotation axis; The inspection result determination module is used to determine the inspection result of the five-axis machine tool according to the coordinate differences between the spherical center coordinates and the circle center coordinates.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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