Optical processing calibration method, computer device and storage medium

Abstract

The present application relates to the technical field of optical processing, and particularly relates to an optical processing calibration method, computer equipment and a storage medium, a machining point of a machining tool is taken as a TCP to be calibrated, and a tool TCP position matrix is obtained; a preset angle is set, and a desired sensor TCP position matrix of a displacement sensor is obtained according to the preset angle and the tool TCP position matrix; a measurement path set is generated when an industrial robot takes the sensor TCP position matrix as a TCP according to machining requirements; the industrial robot is controlled to drive the displacement sensor to move along the measurement path set along a machining workpiece, a pose set of the movement of the industrial robot is obtained, and a machining track is determined; the machining workpiece is rotated at the preset angle, and the machining track completely covers the upper surface of the machining workpiece, and at this time, the optical processing calibration of the industrial robot is completed. The calibration operation method provided by the present application is simple, less equipment is required, and the calibration precision is high.

Description

Technical Field

[0001] This invention belongs to the field of optical processing technology, and particularly relates to an optical processing calibration method, computer equipment, and storage medium. Background Technology

[0002] With the rapid development of next-generation optical systems, higher demands are being placed on the quantity and quality of optical components in fields such as astronomy, photolithography, and laser fusion. As robotics technology advances, industrial robots play a crucial role in optical processing, particularly in precision machining and polishing. These robots can perform surface processing on optical components, removing minute unevenness and imperfections, and improving surface finish. Compared to expensive CNC machine tools, industrial robots offer higher dynamic performance, greater flexibility, and lower equipment costs. Currently, the integration of various tools with industrial robots, such as robotic magnetorheology, robotic small-head polishing, and robotic wheel polishing, further demonstrates the broad development prospects of industrial robots in the field of optical precision manufacturing.

[0003] However, robotic polishing is limited by the precision of the industrial robot itself. The motion mechanism of an industrial robot typically suffers from assembly errors, gear errors, wear issues, and its own elastic deformation, causing a significant difference between the robot's motion posture and the theoretical value. This spatial position error can often reach the sub-millimeter level. This results in a sub-millimeter level positional error between the tool tip and the theoretical machining point on the workpiece during optical processing, directly affecting the final accuracy of the optical processing. Therefore, accurate calibration of the industrial robot before processing optical components is crucial.

[0004] Existing calibration methods employ external 3D measuring equipment such as laser trackers to assess the spatial positional accuracy of six-axis industrial robots within their machining range, thereby ensuring good pose accuracy during workpiece processing. However, this calibration method involves expensive equipment and cumbersome operation. Furthermore, the elastic deformation and gear backlash between the joints of an industrial robot cause spatial positional errors to vary with pose changes, necessitating consideration of numerous parameters during calibration. Inappropriate algorithm selection or insufficient optimization can lead to inaccurate or unstable calibration results.

[0005] Besides using 3D measurement equipment such as laser trackers, most existing inventions involve installing displacement sensors at the end of the machining tool to calibrate the positional relationship between the tool and the workpiece during the industrial robot machining process. However, due to the size of the installed displacement sensors, the pose of the industrial robot at the calibration time is not exactly the same as the pose during actual machining. That is, the angles of each axis of the industrial robot at the calibration time are different from the pose during actual machining, resulting in inaccurate calibration results. Summary of the Invention

[0006] In view of this, the present invention aims to provide an optical processing calibration method, computer equipment and storage medium, using the workpiece being processed as a reference, a displacement sensor to provide absolute accuracy, and taking advantage of the good repeatability of industrial robots to perform limited accuracy calibration on the workpiece processing trajectory so as to meet the processing requirements.

[0007] To achieve the above objectives, the technical solution created by this invention is implemented as follows:

[0008] An optical processing calibration method for calibrating an industrial robot with a displacement sensor and a processing tool integrated at its free end, comprising:

[0009] S1: Using the machining points of the machining tool as TCP for calibration, the tool TCP position matrix is ​​obtained;

[0010] S2: Set a preset angle, and obtain the desired sensor TCP position matrix of the displacement sensor based on the preset angle and the tool TCP position matrix obtained in step S1.

[0011] S3: Based on the processing requirements, generate a set of measurement paths for the industrial robot when the sensor TCP position matrix obtained in step S2 is the TCP.

[0012] S4: Control the industrial robot to drive the displacement sensor to move along the workpiece according to the measurement path set in step S3, obtain the pose set of the industrial robot's motion, and determine the processing trajectory;

[0013] S5: Rotate the machining trajectory obtained in step S4 at the preset angle in step S2 so that the machining trajectory completely covers the upper surface of the workpiece. At this point, the optical machining calibration of the industrial robot is completed.

[0014] Furthermore, the displacement sensor is mounted on the free end of the industrial robot via a graduated motion mechanism, and the motion mechanism drives the displacement sensor to move; the workpiece is placed on a graduated two-dimensional motion worktable.

[0015] Furthermore, before step S1, the process includes: establishing a workpiece coordinate system based on the position of the industrial robot, adjusting the posture of the workpiece to make the xy plane of the workpiece coordinate system parallel to the surface to be processed of the workpiece.

[0016] Furthermore, the process of obtaining the sensor TCP position matrix in step S2 includes determining the relationship between the sensor TCP position matrix and the tool TCP position matrix using the following formula:

[0017] ;

[0018] Where T represents the inherent attitude matrix calculated based on the mechanical relationships and rotation angles between the mechanical axes of the industrial robot. Represents the sensor TCP position matrix. Represents the TCP coordinates of the displacement sensor. The TCP position matrix represents the tool. The TCP coordinates of the machining tool are represented by θ, the rotation angle is represented by α, the preset angle is represented by α, and the mechanical system parameters are represented by d. The position of the displacement sensor is continuously adjusted until the TCP of the displacement sensor that matches the relationship is found.

[0019] Furthermore, step S2 also includes controlling the displacement sensor to move until the displacement sensor's TCP matches the sensor's TCP position matrix.

[0020] Furthermore, the process of obtaining the pose set of the industrial robot in step S4 includes: controlling the industrial robot to drive the displacement sensor to move along the workpiece according to the measurement path set; during the movement, the displacement sensor measures the position error between the TCP coordinates of the machining tool and the corresponding machining point on the workpiece; adjusting the pose of the industrial robot according to the position error so that the position error is 0.

[0021] Furthermore, the machining trajectory in step S4 is as follows:

[0022] {T Tool2}={T Tool1_Correct_mn}+α;

[0023] Among them, {T Tool2} represents the processing trajectory, {T Tool1_Correct_mn} represents the pose set, and α represents the preset angle.

[0024] Furthermore, in step S5: if the workpiece is rotationally symmetrical, one axis of the industrial robot is rotated at a preset angle so that the processing trajectory completely covers the upper surface of the workpiece; if the workpiece is not rotationally symmetrical, the workpiece is rotated at a preset angle so that the processing trajectory completely covers the surface of the workpiece.

[0025] A computer device includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the optical processing calibration method provided by the present invention.

[0026] A non-transitory computer-readable storage medium storing computer instructions for causing a computer to execute the optical processing calibration method provided by the present invention.

[0027] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0028] In optical processing, industrial robots need to perform repetitive movements at equal intervals along the upper surface of the workpiece. High accuracy is required for displacement along the workpiece normal, while the accuracy requirements for the other two directions are relatively lower. To address this, this invention provides an optical processing calibration method, computer equipment, and storage medium. It uses displacement sensors for limited calibration of the industrial robot. Throughout the calibration process, the kinematic model of the industrial robot is combined with the high repeatability of the robot and the high surface accuracy of the workpiece. Displacement sensors are used to calibrate the industrial robot along the workpiece normal, using the workpiece as a reference. This method requires less equipment and is inexpensive, is simple, and offers high accuracy, meeting the needs of mass production scenarios such as factories. Attached Figure Description

[0029] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0030] Figure 1 A schematic flowchart of the optical processing calibration method described in the embodiments of the present invention;

[0031] Figure 2 A schematic diagram of the structure involved in the optical processing calibration method described in the embodiments of the present invention;

[0032] Figure 3 The calibration path and machining path diagram of the centrally symmetrical workpiece described in the embodiments of the present invention;

[0033] Figure 4 The present invention provides a calibration path, machining path, and workpiece position diagram after rotation applicable to non-centrosymmetric workpieces as described in the embodiments of the present invention.

[0034] Figure 5 A schematic diagram of the computer device described in an embodiment of the present invention.

[0035] Explanation of reference numerals in the attached figures:

[0036] 1. Displacement sensor; 2. Machining tool; 3. Industrial robot; 4. Motion mechanism; 5. Machining workpiece; 6. Two-dimensional motion table; 7. Tool holder; 8. Workpiece holder; 9. Electronic equipment; 10. External device; 11. Processing unit; 12. Bus; 13. Network adapter; 14. Display; 15. (I / O) interface; 16. System memory; 17. Random access memory; 18. Cache memory; 19. Storage system; 20. Utility tool; 21. Program module. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0038] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0039] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0040] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0041] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0042] like Figures 1 to 2 As shown, the optical processing calibration method described in this embodiment of the invention is used to calibrate an industrial robot 3 with a displacement sensor 1 and a processing tool 2 integrated at its free end. The industrial robot 3 serves as the execution unit in the entire calibration and processing process, and is responsible for driving the displacement sensor 1 and the processing tool 2 to calibrate and process the workpiece 5. In this embodiment of the invention, a six-axis robotic arm is specifically used as the industrial robot 3.

[0043] The method provided by this invention includes:

[0044] S1: Using the machining points of machining tool 2 as TCP for calibration, the tool TCP position matrix is ​​obtained. In this embodiment of the invention, the "six-point method" is used for TCP calibration in step S1.

[0045] In some embodiments, the displacement sensor 1 is mounted at the free end of the industrial robot 3 via a graduated motion mechanism 4, and the motion mechanism 4 drives the displacement sensor 1 to move; the workpiece 5 is placed on a graduated two-dimensional motion table 6.

[0046] In this embodiment of the invention, the processing tool 2 is mounted and fixed to the free end flange of the industrial robot 3 via a tool fixing plate 7. Specifically, the processing tool 2 is fixed to the tool fixing plate 7 with screws, and the tool fixing plate 7 is fixed to the free end flange of the industrial robot 3 with screws. The processing tool 2 can be a small grinding head, a magnetorheological polishing wheel, a lathe polishing wheel, or other processing tools. The workpiece 5 is placed on the two-dimensional motion worktable 6 via a workpiece fixing plate 8. Specifically, the workpiece 5 is fixed to the workpiece fixing plate 8 by a pressure plate, and the workpiece fixing plate 8 is fixed to the two-dimensional motion worktable 6 by welding or screws. In this embodiment of the invention, the motion mechanism 4 can be a lead screw mechanism; in other embodiments, it can also be a worm gear or other motion mechanism.

[0047] In some embodiments, before step S1, the method further includes: establishing a workpiece coordinate system based on the position of the industrial robot 3, and adjusting the posture of the workpiece 5 to make the xy plane of the workpiece coordinate system parallel to the surface to be processed of the workpiece 5. In this embodiment of the invention, specifically, the workpiece fixing plate 8 is adjusted to make the xy plane of the workpiece coordinate system parallel to the surface to be processed of the workpiece 5.

[0048] Homogeneous transformation is a commonly used transformation relationship in six-axis serial industrial robots. The homogeneous transformation matrix T is defined as follows: Tool as follows:

[0049] ;

[0050] in, Let P = (x, y, z) represent the rotation matrix, where each element is the rotation angle parameter when the six-axis robotic arm is used as the execution unit, and let P = (x, y, z) represent the translation matrix. At this point, if point P in the TCP contact base coordinate system of machining tool 2... C =(x C ,y C ,z C When ), point P can be... C =(x C ,y C ,z C Using the homogeneous transformation matrix T mentioned above Tool Convert to TCP coordinates for machining tool 2, as shown in the following formula:

[0051] ;

[0052] in, This represents the rotation matrix when the six-axis robotic arm drives the machining tool 2, where each element is a rotation angle parameter when the six-axis robotic arm acts as the execution unit to drive the machining tool 2. This yields the following coordinate system for the machining tool 2:

[0053] Tool TCP Position Matrix T Tool2 for ;

[0054] The TCP coordinates of machining tool 2 are .

[0055] S2: Set a preset angle, and obtain the desired sensor TCP position matrix of displacement sensor 1 based on the preset angle and the tool TCP position matrix obtained in step S1.

[0056] The selection principle for the preset angle α is that the preset angle α < 10°. If point P in the TCP contact base coordinate system of displacement sensor 1... C =(x C ,y C ,z C When ), point P can be... C =(x C ,y C ,z C Using the homogeneous transformation matrix T mentioned above Tool Converted to TCP coordinates of displacement sensor 1, as shown in the following formula:

[0057] ;

[0058] in, This represents the rotation matrix when the six-axis robotic arm drives the displacement sensor 1, where each element is a rotation angle parameter when the six-axis robotic arm acts as the actuator to drive the displacement sensor 1. This yields the following coordinate system in which the displacement sensor 1 moves:

[0059] Sensor TCP Position Matrix T Tool1 It can be represented as ;

[0060] The TCP coordinates of displacement sensor 1 are represented as follows: .

[0061] In some embodiments, the process of obtaining the sensor TCP location matrix includes:

[0062] The relationship between the sensor TCP position matrix and the tool TCP position matrix is ​​determined by the following formula:

[0063] ;

[0064] Where T represents the inherent posture matrix calculated based on the mechanical relationship and rotation angle between the mechanical axes in the industrial robot, θ represents the rotation angle of displacement sensor 1 or processing tool 2, α represents the preset angle, and d represents the mechanical system parameters;

[0065] The position of the displacement sensor is continuously adjusted until a TCP of the displacement sensor that matches the relationship is found.

[0066] In some embodiments, step S2 further includes controlling the displacement sensor to move until the displacement sensor's TCP matches the sensor's TCP position matrix.

[0067] For a six-axis robotic arm:

[0068] The position transformation relationship of the TCP of machining tool 2 at its free end relative to the base coordinate system is as follows:

[0069] T C_Tool2 =T Tool2_1 ×T Tool2_2 ×T Tool2_3 ×T Tool2_4 ×T Tool2_5 ×T Tool2_6 ×T Tool2 ;

[0070] Among them, T C_Tool2 This represents a point P in the TCP contact base coordinate system of the six-axis robotic arm driving the machining tool 2. C The TCP position matrix, a tool for timing, Tool2_1 T Tool2_2 T Tool2_3 T Tool2_4 TTool2_5 and T Tool2_6 This represents the inherent attitude matrix calculated based on the mechanical relationships (DH parameters, fixed parameters) and rotation angles between the mechanical axes of the industrial robot 3 (i.e., the six-axis robotic arm).

[0071] The position transformation relationship of the TCP of displacement sensor 1 at its free end relative to the base coordinate system is as follows:

[0072] T C_Tool1 =T Tool1_1 ×T Tool1_2 ×T Tool1_3 ×T Tool1_4 ×T Tool1_5 ×T Tool1_6 ×T Tool1 ;

[0073] Among them, T C_Tool1 This represents a point P in the TCP contact base coordinate system of displacement sensor 1. C The sensor TCP position matrix at time, T Tool1_1 T Tool1_2 T Tool1_3 T Tool1_4 T Tool1_5 and T Tool1_6 This represents the inherent posture matrix calculated based on the mechanical relationships (DH parameters, fixed parameters) and rotation angles between the mechanical axes of the industrial robot 3 (i.e., the six-axis robotic arm).

[0074] When industrial robot 3 uses sensor TCP position matrix T Tool1 and the TCP position matrix T Tool2 Point P in the contact base coordinate system C Since all 12 inherent attitude matrices mentioned above are known quantities, it is necessary to select an appropriate sensor TCP position matrix T. Tool1 and the TCP position matrix T Tool2 The relationship between them makes it possible for the TCP of industrial robot 3 to be determined by the sensor TCP position matrix T. Tool1 Switch to the tool TCP position matrix T Tool2 This can be achieved by rotating only one axis of the industrial robot 3 (i.e., the six-axis robotic arm). In this embodiment of the invention, taking the first axis of the six-axis robotic arm as an example, the following conditions exist:

[0075] ;

[0076] If the above conditions are met, the following must be present:

[0077] T C_Tool2 =T C_Tool1 ;

[0078] Further, there are:

[0079] T Tool2_1 ×T×T Tool2 =T Tool1_1 ×T×T Tool1 ;

[0080] in:

[0081] T=T Tool2_2 ×T Tool2_3 ×T Tool2_4 ×T Tool2_5 ×T Tool2_6 ;

[0082] The corresponding ones are:

[0083] T=T Tool1_2 ×T Tool1_3 ×T Tool1_4 ×T Tool1_5 ×T Tool1_6 .

[0084] Understandably, when rotating one of the other axes of the industrial robot 3 (i.e., the six-axis robotic arm), the inherent posture matrix in the above conditions is replaced. For example, when rotating the second axis of the industrial robot 3 (i.e., the six-axis robotic arm), the above conditions are adjusted accordingly:

[0085] ;

[0086] Correspondingly, to satisfy this condition, the following must be met:

[0087] T Tool2_2 ×T×T Tool2 =T Tool1_2 ×T×T Tool1 ;

[0088] in:

[0089] T=T Tool2_1 ×T Tool2_3 ×T Tool2_4 ×T Tool2_5 ×T Tool2_6 ;

[0090] The corresponding ones are:

[0091] T=T Tool1_1 ×T Tool1_3 ×T Tool1_4 ×T Tool1_5 ×T Tool1_6 .

[0092] The replacement methods for other axes in the rotating industrial robot 3 (i.e., the six-axis robotic arm) are the same as described above, and will not be repeated here.

[0093] As described above, under the aforementioned conditions, rotating only one axis of the industrial robot 3 (i.e., the six-axis robotic arm) achieves TCP (TCP position matrix) of the industrial robot 3, which is determined by the sensor TCP position matrix T. Tool1 Switch to the tool TCP position matrix T Tool2 Taking the first axis of a six-axis rotating robotic arm as an example, according to the DH model of industrial robot 3, we know that:

[0094] ;

[0095] Where, θ Tool1_1 This represents the rotation angle of the first axis. At this point:

[0096] ;

[0097] Wherein, the rotation angle θ of the first axis Tool1_1 The inherent attitude matrix T and the mechanical system parameter d are both known quantities. The TCP coordinates of machining tool 2 are also known. Since it is an invariant variable, the position of displacement sensor 1 is continuously adjusted by motion mechanism 4 until a TCP of displacement sensor 1 that matches the relationship is found.

[0098] S3: Based on the processing requirements, generate the set of measurement paths for industrial robot 3 when the sensor TCP position matrix obtained in step S2 is the TCP.

[0099] In this embodiment of the invention, the set of measurement paths is represented as follows:

[0100] {T sense =f(θ1,θ2,θ3,θ4,θ5,θ6,T Tool1 )};

[0101] Among them, {T sense} represents the set of measurement paths, T sense The measurement pose matrix of industrial robot 3 includes the six-axis rotation angles θ1, θ2, θ3, θ4, θ5, and θ6 of industrial robot 3 in its base coordinate system, and the sensor TCP position matrix T in the motion coordinate system of displacement sensor 1. Tool1 f represents the pose function of industrial robot 3, which is determined by the six joint angles of industrial robot 3.

[0102] The pose function f of industrial robot 3 is further elaborated as follows:

[0103] For each joint angle of industrial robot 3, there exists a transformation matrix T. i :

[0104] ;

[0105] Where i={1,2,3,4,5,6} represents the axis index of industrial robot 3, and d i τ i and a i The DH parameter represents the industrial robot 3, and is a known quantity.

[0106] The industrial robot 3 used in this embodiment of the invention has 6 joint angles, therefore the total transformation matrix T of the industrial robot 3 is... all for:

[0107] ;

[0108] The sensor TCP position matrix T is calculated using the following formula. Tool1 Perform a matrix transformation (Trans) to map the coordinates to the base coordinate system of the industrial robot 3:

[0109] ;

[0110] Where Q0, Q1, Q2, and Q3 represent the quaternions in the matrix transformation Trans.

[0111] At this point, the measurement pose matrix T of industrial robot 3 is obtained by the following formula. sense :

[0112] T sense =T all ×Trans(T Tool1 );

[0113] The above formula can be equivalent to:

[0114] T sense =f(θ1,θ2,θ3,θ4,θ5,θ6,T Tool1 ).

[0115] Typically, industrial robots 3 measure the set of paths {T} Tool1 During movement, the direction measured by displacement sensor 1 is the same as the normal direction of the measured point on the workpiece 5.

[0116] S4: Control the industrial robot 3 to drive the displacement sensor 1 to move along the workpiece 5 according to the measurement path set in step S3, obtain the pose set of the industrial robot 3, and determine the processing trajectory.

[0117] In some embodiments, the process of obtaining the pose set of the industrial robot 3 includes:

[0118] The industrial robot 3 drives the displacement sensor 1 to move along the workpiece 5 according to the measurement path set. During this process, the displacement sensor 1 measures the positional error between the TCP coordinates of the machining tool 2 and the corresponding machining point on the workpiece 5.

[0119] Adjust the pose of industrial robot 3 according to the position error to make the position error 0, and obtain the pose set of industrial robot 3.

[0120] In this embodiment of the invention, the method for adjusting the pose can be an iterative adjustment method, an interpolation method, or other methods. The pose set is represented as:

[0121] ;

[0122] Among them, {T Tool1_Correct_mn} represents the pose set, and θ1', θ2', θ3', θ4', θ5' and θ6' represent the six-axis rotation angles of the six-axis robotic arm after pose adjustment.

[0123] In some embodiments, the processing trajectory is:

[0124] {T Tool2}={T Tool1_Correct_mn}+α;

[0125] Among them, {T Tool2} represents the processing trajectory, {T Tool1_Correct_mn} represents the pose set.

[0126] In this embodiment of the invention, taking the first axis of a six-axis rotating robotic arm as an example, the machining trajectory is as follows:

[0127] ;

[0128] S5: Rotate the machining trajectory obtained in step S4 at the preset angle in step S2 so that the machining trajectory completely covers the surface to be processed of the workpiece 5. At this time, the optical machining calibration of the industrial robot 3 is completed.

[0129] In some embodiments, the process of adjusting the machining trajectory includes: if the workpiece 5 is rotationally symmetrical, rotating one axis of the industrial robot 3 by a preset angle so that the machining trajectory completely covers the surface of the workpiece 5. In this embodiment, this specifically refers to the first axis of the six-axis adjustment structure of the industrial robot 3; if the workpiece 5 is not rotationally symmetrical, rotating the workpiece 5 by a preset angle so that the machining trajectory completely covers the surface of the workpiece 5. In this embodiment, this specifically involves controlling the two-dimensional motion table 6 to drive the workpiece 5 to rotate by a preset angle α.

[0130] In this embodiment of the invention: when the workpiece 5 is a centrally symmetrical workpiece (such as a rectangular workpiece 5), the machining trajectory {T} Tool2 The displacement sensor 1 can cover the surface to be processed on the workpiece 5. That is, when the industrial robot 3 controls the displacement sensor 1 to move according to the pose set, the displacement sensor 1 leaves a mark. Figure 3The measurement trajectory shown is such that the industrial robot 3 controls the machining tool 2 along the machining trajectory {T}. Tool2 During the movement, only the first axis of the industrial robot 3 exhibits an angular deviation of a preset angle α. Therefore, the rotation angles of the other axes of the industrial robot 3 remain unchanged during this process. By adjusting the first axis according to the preset angle (i.e., rotating the first axis according to the preset angle), the machining calibration of the industrial robot 3 can be completed.

[0131] In some other embodiments, there may also be a rotational error on a certain axis (such as the first axis) of the industrial robot 3. (that is, when the first axis will rotate) (The angle, α represents the preset angle), the rotational error of the industrial robot 3 itself. The causes include friction caused by the mechanical structure of the industrial robot itself and motion delay caused by motion transmission, thus requiring consideration of rotational errors. Corrections are made, and the accuracy of this part can be guaranteed by the repeatability accuracy of the industrial robot 3. Therefore, in this embodiment of the invention, rotational error is addressed. The correction process includes: repeatedly adjusting the rotation angle of a certain axis (such as the first axis) of the industrial robot 3 according to a preset angle α until the machining trajectory completely covers the surface of the workpiece 5. At this point, the rotation error correction is completed. Corrections.

[0132] The rotation area of ​​the two-dimensional motion table 6 changes from {Max(θ1'),Min(θ1')} to {Max(θ1')+α,Min(θ1')+α}. Usually, the first axis of the industrial robot 3 has the largest load-bearing capacity and its deformation caused by load posture changes is small. Therefore, it is only necessary to calibrate the angular accuracy of the first axis of the industrial robot 3 within this range.

[0133] When machining workpiece 5 is a non-centrosymmetric workpiece, the machining trajectory {T} Tool2 The surface to be processed on workpiece 5 cannot be covered; that is, when industrial robot 3 controls displacement sensor 1 to move according to pose set, displacement sensor 1 leaves a mark such as... Figure 4 The measurement trajectory shown Figure 4 The black curve represents the initial measurement trajectory of workpiece 5, and the red curve represents the machining trajectory. At this point, the two-dimensional motion table 6 is rotated by a preset angle α, causing workpiece 5 to rotate by the preset angle α. The machining trajectory then completely covers the surface of workpiece 5 to be machined. Figure 4 The blue curve in the image.

[0134] Accordingly, according to embodiments of the present invention, the present invention also provides a computer device, a readable storage medium, and a computer program product.

[0135] Figure 5 This is a schematic diagram of the structure of an electronic device 9 provided in an embodiment of the present invention. Figure 5 A block diagram of an exemplary electronic device 9 suitable for implementing embodiments of the present invention is shown. Figure 5 The electronic device 9 shown is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of the present invention.

[0136] like Figure 5 As shown, electronic device 9 is represented in the form of a general-purpose computing device. Electronic device 9 is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic device 9 can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0137] The components of the electronic device 9 may include, but are not limited to: one or more processors or processing units 11, system memory 16, and bus 12 connecting different system components (including system memory 16 and processing unit 11).

[0138] Bus 12 represents one or more of several bus architectures, including a memory bus or memory controller, a peripheral bus, a graphics acceleration port, a processor, or a local bus using any of the various bus architectures. Examples of these architectures include, but are not limited to, the Industry Standard Architecture (ISA) bus, the Micro Channel Architecture (MAC) bus, the Enhanced ISA bus, the Video Electronics Standards Association (VESA) local bus, and the Peripheral Component Interconnect (PCI) bus.

[0139] Electronic device 9 typically includes a variety of computer system readable media. These media can be any available media that can be accessed by electronic device 9, including volatile and non-volatile media, removable and non-removable media.

[0140] System memory 16 may include computer system readable media in the form of volatile memory, such as random access memory (RAM) 17 and / or cache memory 18. Electronic device 9 may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, storage system 19 may be used to read and write non-removable, non-volatile magnetic media (…). Figure 5 Not shown; usually referred to as a "hard drive"). Although Figure 5Not shown, a disk drive for reading and writing to a removable non-volatile disk (e.g., a "floppy disk") and an optical disk drive for reading and writing to a removable non-volatile optical disk (e.g., a CD-ROM, DVD-ROM, or other optical media) may be provided. In these cases, each drive may be connected to bus 12 via one or more data media interfaces. Storage system 19 may include at least one program product having a set (e.g., at least one) of program modules configured to perform the functions of the embodiments of the present invention.

[0141] A program / utility 20 having a set (at least one) of program modules 21 can be stored in, for example, a storage system 19. Such program modules 21 include, but are not limited to, an operating system, one or more application programs, other program modules, and program data. Each or some combination of these examples may include an implementation of a network environment. Program modules 21 typically perform the functions and / or methods described in the embodiments of the present invention.

[0142] Electronic device 9 can also communicate with one or more external devices 10 (e.g., keyboard, pointing device, display 14, etc.), and with one or more devices that enable a user to interact with electronic device 9, and / or with any device that enables electronic device 9 to communicate with one or more other computing devices (e.g., network card, modem, etc.). This communication can be performed via input / output (I / O) interface 15. Furthermore, electronic device 9 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public networks, such as the Internet) via network adapter 13. As shown, network adapter 13 communicates with other modules of electronic device 9 via bus 12. It should be understood that, although not shown in the figures, other hardware and / or software modules can be used in conjunction with electronic device 9, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0143] The processing unit 11 executes various functional applications and data processing by running programs stored in the system memory 16, such as implementing the optical processing calibration method provided in the embodiments of the present invention.

[0144] This invention also provides a non-transitory computer-readable storage medium storing computer instructions, on which a computer program is stored, wherein the program, when executed by a processor, is the optical processing calibration method provided in all embodiments of this application.

[0145] The computer storage medium of this invention can be any combination of one or more computer-readable media. The computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. More specific examples (a non-exhaustive list) of computer-readable storage media include: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this document, a computer-readable storage medium can be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0146] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media may also be any computer-readable medium other than computer-readable storage media, capable of sending, propagating, or transmitting programs for use by or in connection with an instruction execution system, apparatus, or device.

[0147] The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, optical fiber, RF, etc., or any suitable combination thereof. The computer program code for performing the operations of this invention can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages—such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer can be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0148] This invention also provides a computer program product, including a computer program that, when executed by a processor, implements the optical processing calibration method described above.

[0149] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0150] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. An optical processing calibration method for calibrating an industrial robot with a displacement sensor and processing tool integrated at its free end, characterized in that, include: S1: Using the machining points of the machining tool as TCP for calibration, the tool TCP position matrix is ​​obtained; S2: Set a preset angle, and obtain the desired sensor TCP position matrix of the displacement sensor based on the preset angle and the tool TCP position matrix obtained in step S1. S3: Based on the processing requirements, generate a set of measurement paths for the industrial robot when the sensor TCP position matrix obtained in step S2 is the TCP. S4: Control the industrial robot to drive the displacement sensor to move along the workpiece according to the measurement path set in step S3, obtain the pose set of the industrial robot's motion, and determine the processing trajectory; The process of obtaining the pose set of the industrial robot motion in step S4 includes: controlling the industrial robot to drive the displacement sensor to move along the workpiece according to the measurement path set; During the movement, the displacement sensor measures the positional error between the TCP coordinates of the machining tool and the corresponding machining point on the workpiece; the pose of the industrial robot is adjusted according to the positional error to make the positional error zero. S5: Rotate the machining trajectory obtained in step S4 at the preset angle in step S2 so that the machining trajectory completely covers the upper surface of the workpiece. At this point, the optical machining calibration of the industrial robot is completed.

2. The optical processing calibration method according to claim 1, characterized in that, The displacement sensor is mounted on the free end of the industrial robot via a graduated motion mechanism, which drives the displacement sensor to move; the workpiece is placed on a graduated two-dimensional motion table.

3. The optical processing calibration method according to claim 1, characterized in that, The steps preceding step S1 also include: Establish a workpiece coordinate system based on the position of the industrial robot, and adjust the posture of the workpiece to make the xy plane of the workpiece coordinate system parallel to the surface to be processed on the workpiece.

4. The optical processing calibration method according to claim 1, characterized in that, The process of obtaining the sensor TCP position matrix in step S2 includes: The relationship between the sensor TCP position matrix and the tool TCP position matrix is ​​determined by the following formula: ； Where T represents the inherent attitude matrix calculated based on the mechanical relationships and rotation angles between the mechanical axes of the industrial robot. Represents the sensor TCP position matrix. Represents the TCP coordinates of the displacement sensor. The TCP position matrix represents the tool. The TCP coordinates represent the machining tool, θ represents the rotation angle, α represents the preset angle, and d represents the mechanical system parameters. The position of the displacement sensor is continuously adjusted until a TCP of the displacement sensor that matches the relationship is found.

5. The optical processing calibration method according to claim 1, characterized in that, Step S2 also includes controlling the displacement sensor to move until the displacement sensor's TCP matches the sensor's TCP position matrix.

6. The optical processing calibration method according to claim 1, characterized in that, The machining trajectory in step S4 is as follows: {T Tool2 }={T Tool1_Correct_mn }+α; Among them, {T Tool2 } represents the processing trajectory, {T Tool1_Correct_mn } represents the pose set, and α represents the preset angle.

7. The optical processing calibration method according to claim 1, characterized in that, In step S5: If the workpiece is rotationally symmetrical, one of the axes of the industrial robot is rotated at a preset angle so that the processing trajectory completely covers the upper surface of the workpiece. If the workpiece is not rotationally symmetrical, rotate the workpiece at a preset angle so that the machining trajectory completely covers the surface of the workpiece.

8. A computer device, characterized in that, include: At least one processor; as well as A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the optical processing calibration method according to any one of claims 1 to 7.

9. A non-transitory computer-readable storage medium storing computer instructions, characterized in that, The computer instructions are used to cause the computer to execute the optical processing calibration method according to any one of claims 1 to 7.

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