Robot teaching device and robot teaching method

Abstract

The application relates to the technical field of robot teaching, and provides a robot teaching device and a robot teaching method.The robot teaching device comprises a bottom plate, a first laser emitter and a second laser emitter, two laser emitters, laser intersection in a coincident light point, a visual camera and a distance sensor, the bottom plate is installed on the end mechanism of a robot, the visual camera is used for acquiring image information of laser projection on a to-be-measured plane, the distance sensor is used for determining height difference information of the bottom plate and the to-be-measured plane, and a controller is used for teaching the robot based on the image information and the height difference information.The controller adjusts the robot based on the image information of the visual camera, so that the coincident light point coincides with a certain mark point on the to-be-measured plane, the coordinates of the mark point are determined based on the coordinates of the robot and the relative position relationship between the robot and the coincident light point, automatic calibration of the robot is realized, and the teaching efficiency and the teaching precision are improved.

Description

Technical Field

[0001] This invention relates to the field of robotic arm teaching technology, and more particularly to a robotic arm teaching device and a robotic arm teaching method. Background Technology

[0002] Currently, in semiconductor equipment, the transfer of wafers between various processing units mainly relies on the handling of robotic arms. Due to the high precision requirements of semiconductor equipment, robotic arms need to achieve very high positioning accuracy when placing and picking up wafers from various workstations. However, there are many factors that affect whether robotic arms can accurately place and pick up wafers at various workstations, the most important of which is the teaching process.

[0003] Existing teaching methods mainly involve manually operating a teaching pendant to teach the robotic arm. This process is cumbersome, difficult, and the accuracy of the teaching depends heavily on the experience of the operator, resulting in poor stability. Some methods use through-beam sensors for calibration, but these sensors themselves have poor accuracy and are difficult to calibrate, leading to high teaching difficulty and low efficiency. Summary of the Invention

[0004] This invention aims to at least solve one of the technical problems existing in related technologies. To this end, this invention proposes a robotic arm teaching device to address the shortcomings of existing teaching methods, such as high teaching difficulty, low accuracy, and low efficiency.

[0005] The present invention also proposes a robot arm teaching method, which teaches the robot arm using the above-mentioned robot arm teaching device.

[0006] A robotic arm teaching device according to a first aspect of the present invention includes:

[0007] Base plate, suitable for mounting on the end effector of a robotic arm;

[0008] The first laser emitter and the second laser emitter are both installed on the base plate at a preset angle, and the lasers emitted by the first laser emitter and the second laser emitter intersect at a coincident light point outside the base plate;

[0009] A visual camera and a ranging sensor are mounted on the base plate. The visual camera is used to acquire image information of the lasers emitted by the first laser emitter and the second laser emitter projected onto the plane to be measured. The ranging sensor is used to determine the height difference information between the base plate and the plane to be measured.

[0010] A controller is adapted to connect to the vision camera, the ranging sensor, and the robotic arm, and to teach the robotic arm based on the image information and the height difference information.

[0011] According to an embodiment of the robotic arm teaching device of the present invention, the projections of the laser emitted by the first laser emitter and the laser emitted by the second laser emitter on the base plate are perpendicular.

[0012] According to a second aspect of the present invention, a robot arm teaching method is applied to the robot arm teaching device described above, the method comprising:

[0013] The first light spot and the second light spot are adjusted to coincide at the coincident light spot; wherein, the first light spot is the light spot projected onto the plane to be measured by the laser emitted by the first laser emitter, and the second light spot is the light spot projected onto the plane to be measured by the laser emitted by the second laser emitter; the plane to be measured is provided with marking points;

[0014] Obtain the height difference information between the base plate and the plane to be measured;

[0015] Based on the image information acquired by the vision camera, the horizontal offset between the overlapping light point and the marker point is determined;

[0016] The robotic arm is taught based on the height difference and the horizontal offset.

[0017] According to the robot arm teaching method of the present invention, the method for adjusting the first light spot and the second light spot to coincide includes:

[0018] The robotic arm is controlled to raise to a certain height, and the change in the distance between the first light spot and the second light spot is judged;

[0019] As the distance between the first light spot and the second light spot decreases, the robotic arm is controlled to rise until the first light spot and the second light spot coincide.

[0020] As the distance between the first light spot and the second light spot increases, the robotic arm is controlled to lower until the first light spot and the second light spot coincide.

[0021] The robotic arm teaching method according to an embodiment of the present invention further includes, before determining the horizontal offset between the coincident light point and the marker point based on the image information acquired by the vision camera:

[0022] Acquire visual calibration data and angle information of the end effector of the robotic arm;

[0023] Determining the horizontal offset between the overlapping light point and the marker point based on the image information acquired by the visual camera includes:

[0024] Based on the image information, determine the first pixel coordinates corresponding to the overlapping light point and the second pixel coordinates corresponding to the marker point;

[0025] Based on the visual calibration data, the angle information, the first pixel coordinates, and the second pixel coordinates, the horizontal offset between the overlapping light point and the marker point is determined.

[0026] According to the robot arm teaching method of the present invention, a visual calibration plate is provided on the plane to be tested, the image information includes an image of the visual calibration plate, and the visual calibration data is obtained based on the parsing of the image information.

[0027] According to an embodiment of the present invention, the method for teaching a robotic arm, wherein teaching the robotic arm based on the height difference and the horizontal offset includes:

[0028] Based on the height difference, determine the height coordinates of the plane to be measured;

[0029] Based on the horizontal offset, control the movement of the robotic arm;

[0030] Determine the first horizontal offset between the overlapping light point and the marker point after the robot arm moves;

[0031] If the first horizontal offset is less than a preset threshold, the coordinates of the robotic arm are recorded to complete the teaching process;

[0032] If the first horizontal offset is greater than the preset threshold, the robot arm is controlled to move according to the first horizontal offset.

[0033] According to an embodiment of the present invention, after controlling the movement of the robotic arm based on the first horizontal offset, the method further includes:

[0034] Determine the second horizontal offset between the coincident light point and the marker point after the robot arm moves;

[0035] If the second horizontal offset is greater than the preset threshold, control the robotic arm to descend;

[0036] Based on the image information, the coordinates of the third pixel and the fourth pixel are determined; the third pixel coordinates are the pixel coordinates corresponding to the first light point in the image information, and the fourth pixel coordinates are the pixel coordinates corresponding to the second light point in the image information.

[0037] The robotic arm is calibrated based on the first pixel coordinate, the third pixel coordinate, and the fourth pixel coordinate.

[0038] According to the robot arm teaching method of the present invention, the step of correcting the robot arm based on the first pixel coordinates, the third pixel coordinates, and the fourth pixel coordinates includes:

[0039] The deflection angle of the robotic arm is determined based on the first pixel coordinate, the third pixel coordinate, and the fourth pixel coordinate.

[0040] The actual positional deviation between the overlapping light point and the marker point is determined based on the third pixel coordinate, the fourth pixel coordinate, and the deflection angle.

[0041] The robotic arm is corrected based on the actual position deviation.

[0042] The robotic arm teaching method according to an embodiment of the present invention further includes:

[0043] Obtain the first distance between the coincident light point and the base plate, and the second distance between the plane to be measured and the coincident light point;

[0044] Determine the positional relationship information between the plane to be tested and the coincident light point, wherein the positional relationship information includes whether the plane to be tested is above the coincident light point or below the coincident light point;

[0045] Based on the positional relationship information, the first distance, and the second distance, the height difference between the base plate and the plane to be measured is determined.

[0046] The above-described one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0047] This invention provides a robot arm teaching device and method. The robot arm teaching device includes a base plate adapted to be mounted on the end effector of a robot arm; a first laser emitter and a second laser emitter, both mounted at a preset angle on the base plate, with the lasers emitted by the first and second laser emitters intersecting at a coincident point outside the base plate; a vision camera and a distance sensor mounted on the base plate, the vision camera acquiring image information of the projection of the lasers emitted by the first and second laser emitters onto a plane to be measured, and the distance sensor determining the height difference between the base plate and the plane to be measured; and a controller adapted to be connected to the vision camera, the distance sensor, and the robot arm, for teaching the robot arm based on the image information and the height difference information. The controller adjusts the robot arm based on the image information from the vision camera so that the coincident point coincides with a marker point on the plane to be measured. Based on the coordinates of the robot arm and the relative positional relationship between the robot arm and the coincident point, the coordinates of the marker point are determined, achieving automatic calibration of the robot arm and improving teaching efficiency and accuracy.

[0048] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 This is a simplified structural diagram of the robotic arm teaching device provided in an embodiment of the present invention;

[0051] Figure 2 This is a flowchart illustrating the robotic arm teaching method provided in an embodiment of the present invention;

[0052] Figure 3 This is a side view of the robotic arm teaching device provided in an embodiment of the present invention;

[0053] Figure 4 This is a schematic diagram of image information captured by a vision camera provided in an embodiment of the present invention;

[0054] Figure 5 This is a schematic diagram of the structure of the robotic arm teaching device provided in an embodiment of the present invention.

[0055] Figure label:

[0056] 1. Base plate; 2. First laser emitter; 3. Second laser emitter; 4. Vision camera; 5. Range sensor; 6. Mounting holes; 7. Vision calibration plate. Detailed Implementation

[0057] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0058] In the description of the embodiments of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0059] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" 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. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention based on the specific circumstances.

[0060] In embodiments of the present invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0061] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0062] One embodiment of the present invention, in conjunction with Figures 1 to 5 As shown, a robot arm teaching device and a robot arm teaching method are provided.

[0063] According to one embodiment of the present invention, such as Figure 1 and Figure 5As shown, the robot teaching device includes a base plate 1, suitable for mounting on the end effector of the robot; a first laser emitter 2 and a second laser emitter 3, both mounted on the base plate 1 at a preset angle, the lasers emitted by the first laser emitter 2 and the second laser emitter 3 intersecting at a coincident light point outside the base plate 1; a vision camera and a distance sensor 5, mounted on the base plate 1, the vision camera 4 being used to acquire image information of the projection of the lasers emitted by the first laser emitter 2 and the second laser emitter 3 onto the plane to be measured, and the distance sensor 5 being used to determine the height difference information between the base plate 1 and the plane to be measured; and a controller (not shown in the figure), suitable for connecting to the vision camera 4, the distance sensor 5 and the robot, and for teaching the robot based on the image information and the height difference information.

[0064] It is understood that one or more mounting holes 6 can be provided on the base plate 1, and the base plate 1 is mounted on the end effector of the robot through the mounting holes 6; the first laser emitter 2 and the second laser emitter 3 are both mounted on the base plate 1 at the same preset angle, which can be an acute angle or an obtuse angle, so that the lasers emitted by the first laser emitter 2 and the second emitter intersect at a coincident light point outside the base plate 1. The distance and relative position between the coincident light point and the base plate 1 are determined, and the distance and position between the base plate 1 and the center of the robot are also determined. Therefore, the controller can move the position of the robot based on the vision camera 4 so that the coincident light point coincides with a certain mark point on the plane to be measured. This mark point can be, for example, the center point of a certain workstation. Then, based on the coordinates of the robot and the relative positional relationship between the robot and the coincident light point, the coordinates of the mark point are determined, thereby realizing automatic calibration of the robot and improving teaching efficiency and teaching accuracy.

[0065] To facilitate image capture and simplify calculations, when the vision camera 4 and the distance sensor 5 are mounted on the base plate 1, it can be ensured that both the vision camera 4 and the distance sensor 5 are mounted perpendicular to the plane where the end effector of the robot is located.

[0066] According to one embodiment of the present invention, the projections of the laser emitted by the first laser emitter 2 and the laser emitted by the second laser emitter 3 onto the base plate 1 are perpendicular, which facilitates the calculation of the overlapping light points and the positional relationship between the first light point and the second light point. The first light point is the light point projected onto the plane to be measured by the laser emitted by the first laser emitter 2, and the second light point is the light point projected onto the plane to be measured by the laser emitted by the second laser emitter 3.

[0067] Furthermore, the distance between the first laser emitter 2 and the vision camera 4 can be adjusted to be equal to the distance between the second laser emitter 3 and the vision camera 4, and the overlapping light point is located in the direction directly facing the lens of the vision camera 4, which facilitates the analysis of the image information captured by the vision camera 4. Based on this, the robot arm teaching method of the following embodiment will be described.

[0068] Furthermore, such as Figure 4 As shown, a fixture can also be installed on the plane to be measured, and a vision calibration plate 7 can be installed on the fixture to correct the lens abrupt change of the vision camera and determine the conversion relationship between physical size and pixels.

[0069] In an alternative implementation, the position of the overlapping light point can also be aligned with the center point of the wafer when the robot grips the wafer. When the overlapping light point coincides with the mark point on the plane to be measured, the center point of the wafer also coincides with the mark point, which facilitates teaching.

[0070] Another embodiment of the present invention provides a method for teaching a robotic arm, such as... Figure 2 As shown, the method applied to the above-mentioned robotic arm teaching device includes:

[0071] S201, adjust the first light spot and the second light spot to coincide at the coincident light spot; wherein, the first light spot is the light spot projected onto the plane to be measured by the laser emitted by the first laser emitter, and the second light spot is the light spot projected onto the plane to be measured by the laser emitted by the second laser emitter; a marker point is set on the plane to be measured;

[0072] Understandably, the marker point can be the center point of the wafer at a certain workstation. First, the robot arm is moved to a coarse adjustment position at that workstation. Then, the robot arm is controlled to rise or fall so that the coincident light spot is precisely displayed on the plane to be measured. Optionally, the method for adjusting the first and second light spots to coincide can be:

[0073] The robot arm is raised to a certain height, and the change in the distance between the first and second light spots is judged. When the distance between the first and second light spots decreases, the robot arm is raised until the first and second light spots coincide. When the distance between the first and second light spots increases, the robot arm is lowered until the first and second light spots coincide.

[0074] When the robotic arm is raised to a certain height, the distance between the first and second light spots decreases compared to before the robotic arm was raised, indicating that the position of the overlapping light spot is below the plane to be measured. At this time, the controller controls the robotic arm to continue to raise until the vision camera detects that the first and second light spots on the plane to be measured coincide.

[0075] S202, Obtain the height difference information between the base plate and the plane to be measured;

[0076] In an optional implementation, the distance between the base plate and the plane to be measured can be obtained by a distance sensor, and the height difference information between the base plate and the plane to be measured can be obtained. Then, the height offset between the robot and the marker point can be determined, so as to compensate for the offset of the robot in the height direction.

[0077] In another alternative implementation, such as Figure 3 As shown, the methods for obtaining the height difference information between the base plate and the plane to be measured include:

[0078] Obtain the first distance H between the coincident light point C and the base plate, and the second distance H between the plane to be measured P and the coincident light point. AA’ Determine the positional relationship between the plane to be measured P and the coincident light point C. The positional relationship information includes whether the plane to be measured P is above or below the coincident light point C. Based on the positional relationship information, the first distance H and the second distance H AA’ Determine the height difference between the base plate and the plane P to be measured.

[0079] Understandably, since the position of the coincident light point C is fixed, the first distance H between the coincident light point C and the base plate can be predetermined. If the plane to be measured P is located above the coincident light point C, then the height difference information is HH. AA’ If the plane P to be measured is located below the coincident light point C, then the height difference information is H+H. AA’ The second distance H AA’ The calculation formula is:

[0080] H AA’＝ L A’C ×tgβ=L AB ×sin45°×tgβ

[0081] Where A' is the projection point of the first light point A onto the reference plane where the coincident light point C is located, and L A’C Let L be the distance between A' and C. AB β is the distance between the first light spot A and the second light spot B, and β is the angle between the first laser emitter and the second laser emitter and the base plate, which is the preset angle in the above embodiment.

[0082] S203, Based on the image information acquired by the vision camera, determine the horizontal offset between the overlapping light point and the marker point;

[0083] It is understandable that in this embodiment, in order to facilitate the correction of the image information acquired by the vision camera and determine the true distance between each light point on the plane to be measured, before determining the horizontal offset between the overlapping light point and the marker point, it is also necessary to acquire vision calibration data and the angle information of the end effector of the robot arm to help the controller determine the internal and external parameters of the vision camera, achieve accurate vision measurement and positioning, ensure that the calculated horizontal offset is more accurate, and improve the teaching accuracy.

[0084] In an optional implementation, a fixture can be set on the plane to be measured, i.e., the workstation, and a vision calibration plate can be installed on the fixture. The vision camera can simultaneously acquire the projection information of the lasers emitted by the first laser emitter and the second laser emitter on the plane to be measured, as well as the image of the vision calibration plate. The vision calibration data can be obtained by parsing the image information captured by the vision camera.

[0085] Understandably, visual calibration boards, when applied in machine vision, can be used to correct lens abrupt changes in visual cameras, determine the conversion relationship between physical dimensions and pixels, and determine the relationship between the three-dimensional geometric position of a point on the surface of a spatial object and its corresponding point in the image. This establishes the geometric model of the visual camera's imaging. By photographing an array of flat plates with a fixed-space pattern using the camera, and through calibration algorithm calculations, the geometric model of the visual camera can be derived. Furthermore, it can be used to provide a set of known feature points or patterns. By identifying and measuring the positions of these feature points in the image, the camera's internal parameters (such as focal length, principal point position, etc.) and external parameters (such as camera attitude, rotation and translation matrices, etc.) can be derived. These parameters are crucial for achieving accurate visual measurement and target localization. Further, the visual calibration board can be a checkerboard calibration board, a circular calibration board, or a grayscale calibration board, etc., and this embodiment does not specifically limit this.

[0086] Understandably, since the vision camera is mounted perpendicular to the plane where the end effector of the robot arm is located, the angle information of the robot arm will affect the shooting angle of the vision camera, thus having a certain impact on the image information.

[0087] In this embodiment, after determining the visual calibration data and angle information, the horizontal offset between the overlapping light point and the marker point is determined based on the visual calibration data, angle information, first pixel coordinates, and second pixel coordinates. The first and second pixel coordinates are calculated based on the visual calibration data and angle information to determine the actual coordinates of the overlapping light point and the marker point corresponding to the first and second pixel coordinates in the image information. Then, the horizontal offset between the overlapping light point and the marker point is calculated based on their actual coordinates. It is understood that the method of calculating pixel coordinates based on visual calibration data and angle information is existing technology in the field of machine recognition, and will not be described in detail in this embodiment.

[0088] S204 teaches the robot arm based on the height difference and horizontal offset.

[0089] It is understandable that methods for teaching a robotic arm based on height difference and horizontal offset can include:

[0090] Based on the height difference, the height coordinates of the plane to be measured are determined in order to perform coordinate compensation in the height direction for the robot arm.

[0091] Based on the horizontal offset, control the movement of the robot arm; determine the first horizontal offset between the overlapping light point and the marker point after the robot arm moves; if the first horizontal offset is less than a preset threshold, record the coordinates of the robot arm and complete the teaching; if the first horizontal offset is greater than the preset threshold, control the movement of the robot arm according to the first horizontal offset.

[0092] In this embodiment, after calculating the horizontal offset between the overlapping light point and the marker point, the robot arm is controlled to move based on the horizontal offset. Since the robot arm only moves in the horizontal direction, the overlapping light point will still be displayed on the plane to be measured and will move with the robot arm. The first horizontal offset between the overlapping light point and the marker point after the movement is calculated. When the first horizontal offset is less than a preset threshold, it can be considered that the overlapping light point and the marker point have basically overlapped. At this time, the coordinates of the robot arm can be recorded to complete the teaching. When the first horizontal offset is greater than or equal to the preset threshold, it indicates that the horizontal position of the overlapping light point has not been adjusted to the correct position. The robot arm can continue to be controlled to move based on the first horizontal offset to reduce the horizontal offset between the overlapping light point and the marker point.

[0093] According to one embodiment of the present invention, after controlling the movement of the robotic arm based on a first horizontal offset, the method further includes:

[0094] Determine the second horizontal offset between the overlapping light point and the marker point after the robot arm moves; if the second horizontal offset is greater than a preset threshold, control the robot arm to descend; based on image information, determine the third pixel coordinates and the fourth pixel coordinates; the third pixel coordinates are the pixel coordinates corresponding to the first light point in the image information, and the fourth pixel coordinates are the pixel coordinates corresponding to the second light point in the image information; correct the robot arm according to the first pixel coordinates, the third pixel coordinates, and the fourth pixel coordinates.

[0095] In this embodiment, after controlling the robot arm to move based on the first horizontal offset, the second horizontal offset between the overlapping light point and the marker point after the movement is calculated. If the second horizontal offset is less than the preset threshold, it can be considered that the overlapping light point and the marker point have basically overlapped. At this time, the coordinates of the robot arm can be recorded to complete the teaching. If the second horizontal offset is still greater than the preset threshold, and the overlapping light point is still not adjusted to overlap with the marker point after two adjustments of the robot arm, it may be due to the fact that the gripping direction of the robot arm is not perpendicular to the plane to be measured where the workstation is located. At this time, the robot arm can be lowered to a certain height to obtain the pixel coordinates corresponding to the first light point and the second light point, and the robot arm can be mechanically corrected in combination with the previous fourth pixel coordinates.

[0096] According to an embodiment of the present invention, the method for correcting the robotic arm based on the first pixel coordinate, the third pixel coordinate, and the fourth pixel coordinate may include:

[0097] The deflection angle of the robot is determined based on the coordinates of the first, third, and fourth pixels; the actual positional deviation between the coincident light point and the marker point is determined based on the coordinates of the third and fourth pixels and the deflection angle; and the robot is corrected based on the actual positional deviation.

[0098] In another alternative teaching method, the deflection angle α between the gripping direction of the robot and the normal of the measured plane can be determined based on the pixel coordinates of the first and second light points after the robot descends to a certain height, combined with the previous fourth pixel coordinates. Then, based on the third and fourth pixel coordinates, the actual positional deviation between the coincident light point and the marker point is re-determined, and the robot is corrected.

[0099] In this embodiment, for ease of calculation, the distance between the first laser emitter and the vision camera can be adjusted to be equal to the distance between the second laser emitter and the vision camera, and the overlapping light point is located in the direction directly opposite the lens of the vision camera, such as... Figure 4 As shown, the formula for calculating the actual position deviation is:

[0100] X C =X B -L AB ×sin45°×sinα

[0101] Y C =Y A -L AB ×sin45°×sinα

[0102] Where T represents a marker point on the plane to be measured, and a plane coordinate system is established with the marker point T as the origin, X C The x-coordinate of the coincident light point C is represented by Y. C The ordinate of the coincident light point C is represented by X. B L represents the x-coordinate of the second light spot B. AB Y represents the distance between the first light spot A and the second light spot B. A This represents the ordinate of the first light spot A.

[0103] After calculating the actual position deviation, the robot arm is compensated accordingly to achieve correction.

[0104] Understandably, the instructor can use the above method to teach each station of the wafer, thereby enabling the robot arm to automatically calibrate at each station.

[0105] Embodiments of the present invention provide a robot arm teaching device and a robot arm teaching method, comprising a base plate adapted to be mounted on the end effector of a robot arm; a first laser emitter and a second laser emitter, both mounted on the base plate at a preset angle, wherein the lasers emitted by the first laser emitter and the second laser emitter intersect at a coincident light point outside the base plate; a vision camera and a distance sensor, mounted on the base plate, wherein the vision camera is used to acquire image information of the projection of the lasers emitted by the first laser emitter and the second laser emitter onto a plane to be measured, and the distance sensor is used to determine the height difference information between the base plate and the plane to be measured; and a controller adapted to be connected to the vision camera, the distance sensor, and the robot arm, and to teach the robot arm based on the image information and the height difference information. The controller adjusts the robot arm based on the image information from the vision camera so that the coincident light point coincides with a marker point on the plane to be measured. Based on the coordinates of the robot arm and the relative positional relationship between the robot arm and the coincident light point, the coordinates of the marker point are determined, thereby achieving automatic calibration of the robot arm and improving teaching efficiency and accuracy.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of this application.

Claims

1. A method for teaching a robotic arm, characterized in that, This is applied to a robotic arm teaching pendant, the robotic arm teaching pendant comprising: Base plate, suitable for mounting on the end effector of a robotic arm; The first laser emitter and the second laser emitter are both installed on the base plate at a preset angle, and the lasers emitted by the first laser emitter and the second laser emitter intersect at a coincident light point outside the base plate; A visual camera and a ranging sensor are mounted on the base plate. The visual camera is used to acquire image information of the lasers emitted by the first laser emitter and the second laser emitter projected onto the plane to be measured. The ranging sensor is used to determine the height difference information between the base plate and the plane to be measured. A controller is adapted to connect to the vision camera, the ranging sensor, and the robotic arm, and to teach the robotic arm based on the image information and the height difference information; The projections of the laser emitted by the first laser emitter and the laser emitted by the second laser emitter onto the base plate are perpendicular; The method includes: The first light spot and the second light spot are adjusted to coincide at the coincident light spot; wherein, the first light spot is the light spot projected onto the plane to be measured by the laser emitted by the first laser emitter, and the second light spot is the light spot projected onto the plane to be measured by the laser emitted by the second laser emitter; the plane to be measured is provided with marking points; Obtain the height difference information between the base plate and the plane to be measured; Based on the image information acquired by the vision camera, the horizontal offset between the overlapping light point and the marker point is determined; The robotic arm is taught based on the height difference and the horizontal offset. Before determining the horizontal offset between the coincident light point and the marker point based on the image information acquired by the vision camera, the method further includes: Acquire visual calibration data and angle information of the end effector of the robotic arm; Determining the horizontal offset between the overlapping light point and the marker point based on the image information acquired by the visual camera includes: Based on the image information, determine the first pixel coordinates corresponding to the overlapping light point and the second pixel coordinates corresponding to the marker point; Based on the visual calibration data, the angle information, the first pixel coordinates, and the second pixel coordinates, the horizontal offset between the coincident light point and the marker point is determined; the teaching of the robotic arm based on the height difference and the horizontal offset includes: Based on the height difference, determine the height coordinates of the plane to be measured; Based on the horizontal offset, control the movement of the robotic arm; Determine the first horizontal offset between the overlapping light point and the marker point after the robot arm moves; If the first horizontal offset is less than a preset threshold, the coordinates of the robotic arm are recorded to complete the teaching process; If the first horizontal offset is greater than the preset threshold, the robot arm is controlled to move according to the first horizontal offset; After controlling the movement of the robotic arm according to the first horizontal offset, the method further includes: Determine the second horizontal offset between the coincident light point and the marker point after the robot arm moves; If the second horizontal offset is greater than the preset threshold, control the robotic arm to descend; Based on the image information, the coordinates of the third pixel and the fourth pixel are determined; the third pixel coordinates are the pixel coordinates corresponding to the first light point in the image information, and the fourth pixel coordinates are the pixel coordinates corresponding to the second light point in the image information. The robotic arm is calibrated based on the first pixel coordinate, the third pixel coordinate, and the fourth pixel coordinate.

2. The robotic arm teaching method according to claim 1, characterized in that, The method for adjusting the first light spot and the second light spot to coincide includes: The robotic arm is controlled to raise to a certain height, and the change in the distance between the first light spot and the second light spot is judged; As the distance between the first light spot and the second light spot decreases, the robotic arm is controlled to rise until the first light spot and the second light spot coincide. As the distance between the first light spot and the second light spot increases, the robotic arm is controlled to lower until the first light spot and the second light spot coincide.

3. The robotic arm teaching method according to claim 1, characterized in that, A visual calibration plate is provided on the plane to be tested, the image information includes an image of the visual calibration plate, and the visual calibration data is obtained by parsing the image information.

4. The robotic arm teaching method according to claim 1, characterized in that, The step of correcting the robotic arm based on the first pixel coordinates, the third pixel coordinates, and the fourth pixel coordinates includes: The deflection angle of the robotic arm is determined based on the first pixel coordinate, the third pixel coordinate, and the fourth pixel coordinate. The actual positional deviation between the overlapping light point and the marker point is determined based on the third pixel coordinate, the fourth pixel coordinate, and the deflection angle. The robotic arm is corrected based on the actual position deviation.

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