Robot tool coordinate system calibration apparatus and method

Abstract

The application provides a robot tool coordinate system calibration device and method. The robot tool coordinate system calibration device comprises a control device configured to be in communication connection with a robot; a laser device, the laser device comprising a laser emitting module and a laser receiving module, both of which are in communication connection with the control device, the laser emitting module being configured to be capable of forming a cross-shaped laser beam, the laser receiving module being capable of receiving the cross-shaped laser beam, two first laser beams forming the cross-shaped laser beam being perpendicular to each other. The technical scheme of the application can solve the problem of low calibration accuracy and efficiency of the calibration mode of the prior art.

Description

Technical Field

[0001] This invention relates to the field of robot calibration technology, and more specifically, to a robot tool coordinate system calibration device and method. Background Technology

[0002] In the field of modern industrial automation and intelligent manufacturing, robots play a vital role. Their precise motion control and efficient working capabilities are key to achieving production line automation and improving manufacturing precision. The calibration of the robot tool coordinate system, as the cornerstone of ensuring robot operational accuracy, has a decisive impact on the performance of industrial robots.

[0003] Traditional robot tool coordinate system calibration methods primarily rely on manual operation. Operators must coordinate their hands and eyes, using measuring tools or reference points, to determine the precise position and orientation of the robot's end effector in space. This method is not only time-consuming and labor-intensive, but also suffers from limitations in achieving high-precision calibration due to human visual and operational errors. This limitation is particularly pronounced in situations requiring frequent tool changes or micrometer-level precision. With the expanding applications of industrial robots, especially in precision assembly, high-precision machining, and complex trajectory welding—operations demanding extremely high precision—relying solely on manual tool coordinate system calibration is no longer sufficient to meet the demands of modern manufacturing technology. The low efficiency and inconsistent accuracy of manual calibration have become bottlenecks restricting the improvement of robot automation levels and production efficiency. Summary of the Invention

[0004] The main objective of this invention is to provide a robot tool coordinate system calibration device and method that can solve the problems of low calibration accuracy and efficiency in existing calibration methods.

[0005] To achieve the above objectives, according to one aspect of the present invention, a robot tool coordinate system calibration device is provided, comprising: a control device configured to communicate with a robot; and a laser device including a laser emitting module and a laser receiving module, both of which are communicatively connected to the control device. The laser emitting module is configured to form a cross-shaped laser beam, and the laser receiving module is configured to receive the cross-shaped laser beam, wherein two first laser beams forming the cross-shaped laser beam are perpendicular to each other.

[0006] Furthermore, the laser emitting module is configured to also form an outer laser beam, with the cross-shaped laser beam located within the area enclosed by the outer laser beam, and the laser receiving module is able to receive the outer laser beam.

[0007] Furthermore, the outer laser beam is rhomboid or square, and the outer laser beam includes four second laser beams, with the cross-shaped laser beam forming the diagonal of the rhomboid or square.

[0008] Furthermore, the laser emitting module includes two first laser emitting units, and the laser receiving module includes two first laser receiving units. The two first laser emitting units and the two first laser receiving units are arranged in a one-to-one correspondence. The first laser receiving unit is used to receive the first laser beam emitted by the corresponding first laser emitting unit, and the first laser beams emitted by the two first laser emitting units form a cross-shaped laser beam.

[0009] Furthermore, the laser emitting module also includes four second laser emitting units, and the laser receiving module also includes four second laser receiving units. The four second laser emitting units and the four second laser receiving units are arranged in a one-to-one correspondence. The second laser receiving units are used to receive the second laser beam emitted by the corresponding second laser emitting unit, and the second laser beams emitted by the four second laser emitting units form an outer laser beam.

[0010] Furthermore, the laser device also includes four laser components, which are arranged circumferentially at intervals. Two first laser emitting parts are respectively disposed on two of the laser components, and two first laser receiving parts are respectively disposed on the other two laser components to form a cross-shaped laser beam. Four second laser emitting parts and four second laser receiving parts are disposed on the four laser components to form an outer laser beam.

[0011] Furthermore, the laser assembly includes an arc-shaped mounting base with its two end faces perpendicular to each other, and a single end face of the arc-shaped mounting base is used to mount a second laser emitter or a second laser receiver.

[0012] According to another aspect of the present invention, a method for calibrating a robot tool coordinate system is provided, utilizing the robot tool coordinate system calibration device as described above. The calibration method includes: S1: moving the robot tool until its end point contacts one of the first laser beams forming a cross-shaped laser beam, and calibrating the position of the first coordinate axis; S2: moving the robot tool until its end point contacts the intersection of the two first laser beams forming the cross-shaped laser beam, and recording the coordinates of the first calibration point; S3: changing the posture and position of the robot tool, repeating the operations of S1 and S2 above, and recording the coordinates of the second calibration point; S4: changing the posture and position of the robot tool, repeating the operations of S1 and S2 above, and recording the coordinates of the third calibration point.

[0013] Further, after the step of calibrating the position of the first coordinate axis, the robot tool is moved until its end contacts another first laser beam forming a cross-shaped laser beam, and the position of the second coordinate axis is calibrated.

[0014] Furthermore, the step of moving the robot tool until its end contacts the intersection of the two first laser beams forming the cross-shaped laser beam includes: moving the robot tool along the second coordinate axis until its end contacts the intersection of the two first laser beams forming the cross-shaped laser beam.

[0015] Furthermore, the step of moving the robot tool until its end point contacts the intersection of the two first laser beams forming the cross-shaped laser beam includes: making the robot tool perform an arc motion until it contacts another first laser beam in the cross-shaped laser beam to confirm the position of the intersection of the two first laser beams forming the cross-shaped laser beam; and then moving the robot tool toward the position of the intersection of the two first laser beams forming the cross-shaped laser beam until it contacts the intersection of the two first laser beams forming the cross-shaped laser beam.

[0016] Furthermore, the step of moving the robot tool until its end contacts the intersection of the two first laser beams forming the cross-shaped laser beam includes: moving the robot tool until it contacts the intersection of the two first laser beams forming the cross-shaped laser beam; then moving the robot tool vertically upward until its end leaves the intersection of the two first laser beams forming the cross-shaped laser beam; stopping the robot tool and recording the coordinates of the first calibration point.

[0017] Furthermore, prior to the step of controlling the movement of the robotic tool until the end of the robotic tool comes into contact with one of the first laser beams forming the cross-shaped laser beams, the procedure includes: moving the robotic tool into the area enclosed by the outer laser beams.

[0018] The technical solution of this invention includes a control device and a laser device. The laser device includes a laser emitting module and a laser receiving module, both of which are communicatively connected to the control device. The laser emitting module is configured to form a cross-shaped laser beam. The process of obtaining calibration points using the robot tool coordinate system calibration device of this application is as follows: The laser emitting module is turned on, forming a cross-shaped laser beam. The laser receiving module is in a standby state, ready to receive changes in the laser signal. When the robot starts the automated calibration process, under the instruction of the control device, the end effector of the robot tool moves to the position of the cross-shaped laser beam. At this time, the control device guides the end effector of the robot tool to move towards the position of the X-axis or Y-axis. During the calibration process, the end effector of the robot tool can first contact the first laser beam as the X-axis or the first laser beam as the Y-axis. Assuming the robot tool's end effector moves under the control of the control device until it contacts the first laser beam (representing the X-axis), it indicates that the robot tool has reached the X-axis. The laser receiving module detects the change in the laser signal and quickly feeds the signal back to the control device via the communication link. After receiving the signal, the control device causes the robot to complete the X-axis position calibration. Then, under the control of the control device, the robot tool's end effector moves until it contacts the first laser beam (representing the Y-axis), indicating that the robot tool has reached the X-axis. The laser receiving module detects the change in the laser signal and quickly feeds the signal back to the control device via the communication link. After receiving the signal, the control device causes the robot to complete the X-axis position calibration. Finally, the robot tool moves along the X-axis until its end effector contacts the intersection of the two first laser beams. At this point, it indicates that the robot tool has reached the Y-axis. Upon reaching the origin, the laser receiving module detects the change in the laser signal and quickly feeds the signal back to the control device via the communication link. Upon receiving the signal, the control device records the robot's joint angles and the coordinates of the robot tool's end effector as data for the first calibration point. To obtain the second calibration point, the robot, guided by the control device, changes the robot tool's posture and position to ensure that the robot tool's end effector is different from the origin's position and posture. This process is repeated until the robot tool's end effector again simultaneously touches the intersection of the two first laser beams. The control device records the robot's joint angles and the robot tool's end effector coordinates as data for the second calibration point. Finally, the robot readjusts the robot tool's posture and position to ensure a difference from the previous two postures and positions, and then repeats the process to obtain the third calibration point. As can be seen, the entire calibration process fully utilizes the high-precision detection capabilities of the laser emitting and receiving modules, combined with the intelligent control and data processing capabilities of the control device, to achieve automatic calibration of the robot tool's coordinate system, reducing manual intervention and improving both calibration accuracy and efficiency. Attached Figure Description

[0019] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0020] Figure 1 A schematic diagram of the structure of a robot tool coordinate system calibration device according to an embodiment of the present invention is shown;

[0021] Figure 2 It shows Figure 1 Enlarged view of point A in the middle;

[0022] Figure 3 A flowchart of the robot tool coordinate system calibration method of the present invention is shown.

[0023] The above figures include the following reference numerals:

[0024] 10. Control device; 20. Robot; 21. Robot tool; 30. Laser device; 31. First laser emitter; 33. Second laser emitter; 34. Second laser receiver; 35. Laser assembly; 36. Arc-shaped mounting base; 37. Roller; 38. Base; 40. Cross-shaped laser beam; 41. First laser beam; 50. Peripheral laser beam; 51. Second laser beam; 60. First communication line; 70. Second communication line. Detailed Implementation

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] See also Figure 1 and Figure 2 As shown, the present invention provides a robot tool coordinate system calibration device, which includes: a control device 10 configured to communicate with a robot 20; and a laser device 30, which includes a laser emitting module and a laser receiving module, both of which are communicatively connected to the control device 10. The laser emitting module is configured to form a cross-shaped laser beam 40, and the laser receiving module is configured to receive the cross-shaped laser beam 40. The two first laser beams 41 forming the cross-shaped laser beam 40 are perpendicular to each other.

[0027] In this embodiment, the control device 10 is communicatively connected to the robot 20 and is used to send control commands to the robot 20, instructing the robot 20 to move to a specific position and posture for calibration. Simultaneously, the control device 10 can receive status information from the robot 20, including its current position, posture data, and joint angles, for real-time monitoring of the robot 20's motion state and position, ensuring the accuracy of the calibration process. Both the laser emitting module and the laser receiving module are communicatively connected to the control device 10, enabling the control device 10 not only to control the laser emission but also to receive signal changes detected by the laser receiving module in real time. When the end of the robot tool 21 touches or approaches the laser beam, the laser receiving module detects a change or interruption in the laser signal intensity and immediately sends information to the control device 10 via the communication connection. The robot tool 21 is mounted on the end of the robot 20 (e.g., a robotic arm).

[0028] The robot tool coordinate system calibration device of this application is used to obtain and determine the calibration point of the tool coordinate system. The laser emission module can form a cross-shaped laser beam 40. The two first laser beams 41 that form the cross-shaped laser beam 40 serve as the X-axis and Y-axis of the robot tool coordinate system, respectively, and the intersection of the two first laser beams 41 serves as the origin.

[0029] Specifically, the process of obtaining calibration points using the robot tool coordinate system calibration device of this application is as follows: the laser emitting module is turned on to form a cross-shaped laser beam 40, and the laser receiving module is in standby mode to receive changes in the laser signal. When the robot 20 starts the automated calibration process, under the instruction of the control device 10, the end of the robot tool 21 is moved to the position of the cross-shaped laser beam 40. At this time, the control device 10 guides the end of the robot tool 21 to move towards the position of the X-axis or Y-axis. During the calibration process, the end of the robot tool 21 can first contact the first laser beam 41 as the X-axis or the first laser beam 41 as the Y-axis. Assuming that the end effector of robot tool 21 moves under the control of control device 10 to contact the first laser beam 41 (which serves as the X-axis), it indicates that robot tool 21 has reached the X-axis. The laser receiving module detects the change in the laser signal and quickly feeds the signal back to control device 10 via the communication link. After receiving the signal, control device 10 causes robot 20 to complete the calibration of its X-axis position. Then, under the control of control device 10, the end effector of robot tool 21 moves to contact the first laser beam 41 (which serves as the Y-axis), indicating that robot tool 21 has reached the X-axis. The laser receiving module detects the change in the laser signal and quickly feeds the signal back to control device 10 via the communication link. After receiving the signal, control device 10 causes robot 20 to complete the calibration of its X-axis position. Then, robot tool 21 moves along the X-axis until the end effector of robot tool 21 contacts the intersection of the two first laser beams 41. At this point, it indicates that robot tool 21 has reached the X-axis. Having reached the origin, the laser receiving module detects the change in the laser signal and quickly feeds the signal back to the control device 10 via the communication link. Upon receiving the signal, the control device 10 records the joint angles of the robot 20 and the coordinates of the end effector of the robot tool 21 as the data for the first calibration point. To obtain the second calibration point, the robot 20, guided by the control device 10, changes the posture and position of the robot tool 21 to ensure that the end effector of the robot tool 21 is different from the origin in both position and posture. This process is repeated until the end effector of the robot tool 21 simultaneously touches the intersection of the two first laser beams 41 again. The control device 10 records the joint angles of the robot 20 and the coordinates of the end effector of the robot tool 21 as the data for the second calibration point. Finally, the robot 20 readjusts the posture and position of the robot tool 21 to ensure that it differs from the previous two postures and positions, and then repeats the process to obtain the third calibration point. After obtaining the data for the three calibration points, the control device 10 can perform data processing, calculating the translation and rotation parameters of the robot tool coordinate system based on the calibration points, and finally determining the tool coordinate system of the robot 20.As can be seen from the above, the entire calibration process makes full use of the high-precision detection capabilities of the laser emitting module and the laser receiving module, combined with the intelligent control and data processing capabilities of the control device 10, which can realize the automatic calibration of the robot tool coordinate system, reduce manual intervention, and improve both the accuracy and efficiency of calibration.

[0030] It should be noted that the calibration device of this application is capable of real-time calibration of the robot tool coordinate system.

[0031] In one embodiment, the laser emitting module is a laser transmitter, and the laser receiving module is a laser receiver. The structures of the laser transmitter and laser receiver adopt existing technologies and will not be described in detail here. (See also...) Figure 1 and Figure 2 As shown, in one embodiment of the present invention, the laser emitting module is configured to also form an outer laser beam 50, and a cross-shaped laser beam 40 is located in the area enclosed by the outer laser beam 50, and the laser receiving module is able to receive the outer laser beam 50.

[0032] In this embodiment, during the automated calibration process, the robot tool 21 can move freely within the area enclosed by the peripheral laser beams 50. The laser receiving module can receive the laser signals of all the laser beams forming the peripheral laser beams 50. Once the robot tool 21 comes into contact with the peripheral laser beams 50, the control device 10 can immediately receive an alarm signal and adjust the movement of the robot 20 in a timely manner, thereby reducing the time it takes for the robot tool 21 to move to the intersection of the cross-shaped laser beams 40, thus speeding up the calibration process.

[0033] See also Figure 1 and Figure 2 As shown, in one embodiment of the present invention, the peripheral laser beam 50 is rhomboid or square, and the peripheral laser beam 50 includes four second laser beams 51, and the cross-shaped laser beam 40 forms the diagonal of the rhomboid or square.

[0034] In this embodiment, the outer laser beam 50 of the rhombus or square shape serves as a boundary, which can monitor in real time whether the robot tool 21 is approaching or exceeding the calibration range, so that the robot tool 21 can quickly locate the area where the cross-shaped laser beam 40 is located, reducing the time of blind searching by the robot tool 21.

[0035] It should be noted that the outer laser beam 50 can also be a quadrilateral other than a rhombus or a square, including but not limited to a rectangle, parallelogram, trapezoid, etc.

[0036] See also Figure 1 and Figure 2As shown, in one embodiment of the present invention, the laser emitting module includes two first laser emitting units 31, and the laser receiving module includes two first laser receiving units. The two first laser emitting units 31 and the two first laser receiving units are arranged in a one-to-one correspondence. The first laser receiving unit is used to receive the first laser beam emitted by the corresponding first laser emitting unit 31. The first laser beams emitted by the two first laser emitting units 31 form a cross-shaped laser beam 40.

[0037] With the above settings, a cross-shaped laser beam 40 can be formed.

[0038] See also Figure 1 and Figure 2 As shown, in one embodiment of the present invention, the laser emitting module further includes four second laser emitting units 33, and the laser receiving module further includes four second laser receiving units 34. The four second laser emitting units 33 and the four second laser receiving units 34 are arranged in a one-to-one correspondence. The second laser receiving units 34 are used to receive the second laser beam emitted by the corresponding second laser emitting unit 33. The second laser beams emitted by the four second laser emitting units 33 form an outer laser beam 50.

[0039] With the above settings, an outer laser beam 50 can be formed to serve as a boundary, thereby enabling the robot tool 21 to quickly locate the area where the cross-shaped laser beam 40 is located, reducing the time spent by the robot tool 21 blindly searching.

[0040] See also Figure 1 and Figure 2 As shown, in one embodiment of the present invention, the laser device 30 further includes four laser components 35, which are arranged at intervals along the circumference. Two first laser emitting parts 31 are respectively disposed on two of the laser components 35, and two first laser receiving parts are respectively disposed on the other two laser components 35 to form a cross-shaped laser beam 40. Four second laser emitting parts 33 and four second laser receiving parts 34 are disposed on the four laser components 35 to form a peripheral laser beam 50.

[0041] In this embodiment, four laser components 35 are arranged in two rows and two columns. The first laser emitting part 31 and the first laser receiving part are respectively arranged on two laser components 35 arranged diagonally to form a cross-shaped laser beam 40. Eight components (i.e., four second laser emitting parts 33 and four second laser receiving parts 34) are evenly arranged on the four laser components 35, that is, each laser component 35 is provided with two components (both components are second laser emitting parts 33; or both are second laser receiving parts 34; or one is a second laser emitting part 33 and the other is a second laser receiving part 34) to finally form the outer laser beam 50.

[0042] In one embodiment, the peripheral laser beam 50 is square. The four laser components 35 are named laser component A, laser component B, laser component C, and laser component D, respectively. Laser components A and B are arranged diagonally, as are laser components C and D. Laser component A has two second laser emitting parts 33 and one first laser emitting part 31, with the first laser emitting part 31 located between the two second laser emitting parts 33. Laser component B has two second laser receiving parts 34 and one first laser receiving part, with the first laser receiving part located between the two second laser receiving parts 34. Laser component C has one second laser receiving part 34, one first laser emitting part 31, and one second laser emitting part 33. Component D is provided with a second laser emitting part 33, a first laser receiving part, and a second laser receiving part 34. The first laser emitting part 31 on laser component A is correspondingly arranged with the first laser receiving part on laser component B. The two second laser emitting parts 33 on laser component A are correspondingly arranged with the two second laser receiving parts 34 on laser component B. The second laser receiving part 34 on laser component C is correspondingly arranged with the second laser emitting part 33 on laser component D. The first laser emitting part 31 on laser component C is correspondingly arranged with the first laser receiving part on laser component D. The second laser emitting part 33 on laser component C is correspondingly arranged with the second laser receiving part 34 on laser component D.

[0043] See also Figure 1 and Figure 2 As shown, in one embodiment of the present invention, the laser assembly 35 includes an arc-shaped mounting base 36, the two end faces of the arc-shaped mounting base 36 being perpendicular to each other, and a single end face of the arc-shaped mounting base 36 being used to mount a second laser emitting part 33 or a second laser receiving part 34.

[0044] In this embodiment, the two end faces of the arc-shaped mounting base 36 are perpendicular to each other, which can achieve precise alignment of the second laser emitting part 33 and the second laser receiving part 34 within a limited space.

[0045] See also Figure 1 and Figure 2 As shown, in one embodiment of the present invention, the laser device 30 further includes a base 38, the laser component 35 is mounted on the base 38, and the bottom of the base 38 is provided with rollers 37 to facilitate the movement of the laser device 30.

[0046] See also Figure 1 and Figure 2 As shown, in one embodiment of the present invention, the laser device 30 further includes a first communication line 60 and a second communication line 70. The control device 10 is connected to the laser device 30 via the first communication line 60, and the control device 10 is connected to the robot 20 via the second communication line 70.

[0047] like Figure 3 As shown, the present invention also provides a robot tool coordinate system calibration method. This robot tool coordinate system calibration method utilizes the robot tool coordinate system calibration device described above. The calibration method includes: S1: moving the robot tool 21 until the end of the robot tool 21 contacts one of the first laser beams 41 forming the cross-shaped laser beam 40, and calibrating the position of the first coordinate axis; S2: moving the robot tool 21 until the end of the robot tool 21 contacts the intersection point of the two first laser beams 41 forming the cross-shaped laser beam 40, and recording the coordinates of the first calibration point; S3: changing the posture and position of the robot tool 21, repeating the above operations S1 and S2, and recording the coordinates of the second calibration point; S4: changing the posture and position of the robot tool 21, repeating the above operations S1 and S2, and recording the coordinates of the third calibration point.

[0048] In this embodiment, the first coordinate axis is either the first laser beam serving as the X-axis or the first laser beam serving as the Y-axis. The robot tool 21 is moved towards the location of the cross-shaped laser beam 40 until its end touches one of the first laser beams in the cross-shaped laser beam 40 (assuming it touches the first laser beam serving as the Y-axis). At this point, the laser receiving module detects a change in the laser signal and sends a feedback signal to the control device 10, indicating that the end of the robot tool 21 has reached the Y-axis position, thus completing the calibration of the first coordinate axis (Y-axis). Subsequently, the robot tool 21 is further controlled to move until it contacts the intersection of the two first laser beams 41 forming the cross-shaped laser beam 40. When the robot tool 21 touches the intersection, the laser receiving module detects a signal change and feeds this information back to the control device 10. The control device 10 records the joint angle of the robot 20 and the coordinates of the end of the robot tool 21 at this time as data for the first calibration point. Then, the posture and position of the robot tool 21 are changed, and different... The robot tool 21 is in a certain state during steps S1 and S2. Steps S1 and S2 are repeated until the end of the robot tool 21 contacts the intersection of the two first laser beams 41 that form the cross-shaped laser beam 40. At this time, the control device 10 records the joint angle of the robot 20 and the coordinates of the end of the robot tool 21 as the data of the second calibration point. Finally, the posture and position of the robot tool 21 are changed again so that the posture and position of the robot tool 21 are different from the posture and position when the first and second calibration points are obtained. Steps S1 and S2 are repeated until the end of the robot tool 21 contacts the intersection of the two first laser beams 41 that form the cross-shaped laser beam 40. At this time, the control device 10 records the joint angle of the robot 20 and the coordinates of the end of the robot tool 21 as the data of the third calibration point, combined with the data of the first two calibration points. The above calibration process utilizes the cooperation of the control device 10, the laser emitting module, and the laser receiving module. By repeatedly changing the posture and position of the robot tool 21, data from three calibration points can be obtained. Moreover, the above process does not require manual intervention and can achieve automated calibration, which greatly improves the efficiency and accuracy of calibration.

[0049] It should be noted that more than three calibration points can be obtained according to actual calibration needs. The specific steps are the same as above, that is, change the posture and position of the robot tool 21 so that the end of the robot tool 21 contacts the intersection of the two first laser beams 41 that form the cross-shaped laser beam 40 again.

[0050] Furthermore, after obtaining three or more calibration points, how to obtain the final robot tool coordinate system? Taking the acquisition of three calibration points as an example, the specific steps are as follows: By analyzing the joint angle data of the three measurements, the change in the robot 20's posture is calculated. This involves calculating the rotation matrix, which can be represented by quaternions or Euler angles, and then converted into a rotation matrix. Since the end of the robot tool 21 contacts the intersection of the two first laser beams 41 that form the cross-shaped laser beam 40 in all three measurements, this point can be considered as the origin of the robot tool coordinate system in the calibration device coordinate system. In this way, the translation vector of the robot tool coordinate system in space can be determined, that is, the distance between the origin of the robot tool coordinate system and the origin of the calibration device. Then, the rotation matrix and translation vector obtained above are combined to construct the homogeneous transformation matrix of the robot tool coordinate system relative to the calibration device coordinate system. Finally, the position and posture in the robot tool coordinate system are transformed to the robot 20 base coordinate system using the homogeneous transformation matrix. The rotation matrix, translation vector, homogeneous transformation matrix, and steps for transforming the position and orientation of the robot tool coordinate system to the robot's 20-base coordinate system mentioned above can be achieved using existing technologies and will not be elaborated here.

[0051] In one embodiment of the present invention, after the step of calibrating the position of the first coordinate axis, the method includes: moving the robot tool 21 until the end of the robot tool 21 contacts another first laser beam 41 forming the cross-shaped laser beam 40, and then calibrating the position of the second coordinate axis. The step of moving the robot tool 21 until the end of the robot tool 21 contacts the intersection of the two first laser beams 41 forming the cross-shaped laser beam 40 includes: moving the robot tool 21 along the second coordinate axis until the end of the robot tool 21 contacts the intersection of the two first laser beams 41 forming the cross-shaped laser beam 40.

[0052] In this embodiment, the position of the second coordinate axis is calibrated after the position of the first coordinate axis is calibrated. This makes it easier to find the intersection of the first and second coordinate axes. During the calibration process, the robot tool 21 only needs to be moved along the extension direction of the second coordinate axis, which can improve the calibration efficiency.

[0053] In one embodiment of the present invention, the step of moving the robot tool 21 until the end of the robot tool 21 contacts the intersection of the two first laser beams 41 forming the cross-shaped laser beam 40 includes: making the robot tool 21 perform an arc motion until it contacts another first laser beam 41 in the cross-shaped laser beam 40 to confirm the position of the intersection of the two first laser beams 41 forming the cross-shaped laser beam 40; and then moving the robot tool 21 toward the position of the intersection of the two first laser beams 41 forming the cross-shaped laser beam 40 until it contacts the intersection of the two first laser beams 41 forming the cross-shaped laser beam 40.

[0054] By adopting the above settings, the contact rate between the end of the robot tool 21 and the intersection of the two first laser beams 41 forming the cross-shaped laser beam 40 can be increased, thereby improving the calibration efficiency.

[0055] In one embodiment of the present invention, the step of moving the robot tool 21 until the end of the robot tool 21 contacts the intersection of the two first laser beams 41 forming the cross-shaped laser beam 40 includes: moving the robot tool 21 until it contacts the intersection of the two first laser beams 41 forming the cross-shaped laser beam 40; then moving the robot tool 21 vertically upward until the end of the robot tool 21 leaves the intersection of the two first laser beams 41 forming the cross-shaped laser beam 40; stopping the robot tool 21 and recording the coordinates of the first calibration point.

[0056] Through the above settings, by confirming the contact with the intersection of the two first laser beams that form the cross-shaped laser beam 40, the control device 10 can accurately record the position of the robot tool 21 in space, that is, the coordinates of the first calibration point, thus ensuring the accuracy of the robot tool coordinate system in subsequent calculations.

[0057] In one embodiment of the present invention, before the step of controlling the robot tool 21 to move until the end of the robot tool 21 contacts one of the first laser beams in the cross-shaped laser beams 40, the method includes: moving the robot tool 21 into the area enclosed by the peripheral laser beams 50.

[0058] The above settings can prevent the end of the robot tool 21 from exceeding the calibration area of ​​the robot tool coordinate system.

[0059] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects: a control device and a laser device are provided. The laser device includes a laser emitting module and a laser receiving module. Both the laser emitting module and the laser receiving module are communicatively connected to the control device. The laser emitting module is configured to form a cross-shaped laser beam. The process of obtaining the calibration point using the robot tool coordinate system calibration device of this application is as follows: the laser emitting module is turned on to form a cross-shaped laser beam. The laser receiving module is in a standby state, ready to receive changes in the laser signal. When the robot starts the automated calibration process, under the instruction of the control device, the end of the robot tool is moved to the position of the cross-shaped laser beam. At this time, the control device guides the end of the robot tool to move towards the position of the X-axis or the Y-axis. During the calibration process, the end of the robot tool can first contact the first laser beam as the X-axis or the first laser beam as the Y-axis. Assuming the robot tool's end effector moves under the control of the control device until it contacts the first laser beam (representing the X-axis), it indicates that the robot tool has reached the X-axis. The laser receiving module detects the change in the laser signal and quickly feeds the signal back to the control device via the communication link. After receiving the signal, the control device causes the robot to complete the X-axis position calibration. Then, under the control of the control device, the robot tool's end effector moves until it contacts the first laser beam (representing the Y-axis), indicating that the robot tool has reached the X-axis. The laser receiving module detects the change in the laser signal and quickly feeds the signal back to the control device via the communication link. After receiving the signal, the control device causes the robot to complete the X-axis position calibration. Finally, the robot tool moves along the X-axis until its end effector contacts the intersection of the two first laser beams. At this point, it indicates that the robot tool has reached the Y-axis. Upon reaching the origin, the laser receiving module detects the change in the laser signal and quickly feeds the signal back to the control device via the communication link. Upon receiving the signal, the control device records the robot's joint angles and the coordinates of the robot tool's end effector as data for the first calibration point. To obtain the second calibration point, the robot, guided by the control device, changes the robot tool's posture and position to ensure that the robot tool's end effector is different from the origin's position and posture. This process is repeated until the robot tool's end effector again simultaneously touches the intersection of the two first laser beams. The control device records the robot's joint angles and the robot tool's end effector coordinates as data for the second calibration point. Finally, the robot readjusts the robot tool's posture and position to ensure a difference from the previous two postures and positions, and then repeats the process to obtain the third calibration point. As can be seen, the entire calibration process fully utilizes the high-precision detection capabilities of the laser emitting and receiving modules, combined with the intelligent control and data processing capabilities of the control device, to achieve automatic calibration of the robot tool's coordinate system, reducing manual intervention and improving both calibration accuracy and efficiency.

[0060] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0061] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A robot tool coordinate system calibration apparatus, characterized by, include: The control device (10) is configured to communicate with the robot (20); The laser device (30) includes a laser emitting module and a laser receiving module. Both the laser emitting module and the laser receiving module are communicatively connected to the control device (10). The laser emitting module is configured to form a cross-shaped laser beam (40), and the laser receiving module is capable of receiving the cross-shaped laser beam (40). The two first laser beams (41) forming the cross-shaped laser beam (40) are perpendicular to each other. The laser emitting module is configured to also form an outer laser beam (50), the cross-shaped laser beam (40) is located in the area enclosed by the outer laser beam (50), and the laser receiving module is capable of receiving the outer laser beam (50). The laser emitting module includes two first laser emitting units (31), and the laser receiving module includes two first laser receiving units. The two first laser emitting units (31) and the two first laser receiving units are arranged in a one-to-one correspondence. The first laser receiving unit is used to receive the first laser beam (41) emitted by the corresponding first laser emitting unit (31). The first laser beam (41) emitted by the two first laser emitting units (31) forms the cross-shaped laser beam (40). The laser emitting module further includes four second laser emitting units (33), and the laser receiving module further includes four second laser receiving units (34). The four second laser emitting units (33) and the four second laser receiving units (34) are arranged in a one-to-one correspondence. The second laser receiving units (34) are used to receive the second laser beam (51) emitted by the corresponding second laser emitting unit (33). The second laser beam (51) emitted by the four second laser emitting units (33) forms the peripheral laser beam (50).

2. The robotic tool coordinate system calibration apparatus of claim 1, wherein, The peripheral laser beam (50) is rhomboid or square, and the peripheral laser beam (50) includes four second laser beams (51). The cross-shaped laser beam (40) forms the diagonal of the rhomboid or square.

3. The robotic tool coordinate system calibration apparatus of claim 1, wherein, The laser device (30) further includes four laser components (35), which are arranged circumferentially at intervals. Two first laser emitting parts (31) are respectively disposed on two of the laser components (35), and two first laser receiving parts are respectively disposed on the other two laser components (35) to form the cross-shaped laser beam (40). Four second laser emitting parts (33) and four second laser receiving parts (34) are disposed on the four laser components (35) to form the peripheral laser beam (50).

4. The robotic tool coordinate system calibration apparatus of claim 3, wherein, The laser assembly (35) includes an arc-shaped mounting base (36) with its two end faces perpendicular to each other. A single end face of the arc-shaped mounting base (36) is used to mount the second laser emitting part (33) or the second laser receiving part (34).

5. A robot tool frame calibration method, characterized by, The calibration method, using the robot tool coordinate system calibration device as described in any one of claims 1 to 4, comprises: S1: Move the robot tool (21) until the end of the robot tool (21) contacts one of the first laser beams (41) forming the cross-shaped laser beams (40) to perform position calibration of the first coordinate axis; S2: Move the robot tool (21) until the end of the robot tool (21) contacts the intersection of the two first laser beams (41) that form the cross-shaped laser beam (40), and record the coordinates of the first calibration point; S3: Change the posture and position of the robot tool (21), repeat the above operations S1 and S2, and record the coordinates of the second calibration point; S4: Change the posture and position of the robot tool (21), repeat the above operations S1 and S2, and record the coordinates of the third calibration point.

6. The robot tool coordinate system calibration method of claim 5, wherein, After the step of calibrating the position of the first coordinate axis, the robot tool (21) is moved until the end of the robot tool (21) contacts another first laser beam (41) forming the cross-shaped laser beam (40), and the position of the second coordinate axis is calibrated.

7. The robot tool coordinate system calibration method of claim 6, wherein, The step of moving the robot tool (21) until the end of the robot tool (21) contacts the intersection of the two first laser beams (41) forming the cross-shaped laser beam (40) includes: moving the robot tool (21) along the second coordinate axis until the end of the robot tool (21) contacts the intersection of the two first laser beams (41) forming the cross-shaped laser beam (40).

8. The robot tool frame calibration method of claim 5, wherein, The step of moving the robot tool (21) until the end of the robot tool (21) contacts the intersection of the two first laser beams (41) forming the cross-shaped laser beam (40) includes: The robot tool (21) is made to make an arc motion until it comes into contact with another first laser beam (41) in the cross-shaped laser beam (40) to confirm the position of the intersection of the two first laser beams (41) forming the cross-shaped laser beam (40); Then, the robot tool (21) is moved to the location of the intersection of the two first laser beams (41) that form the cross-shaped laser beam (40) until it contacts the intersection of the two first laser beams (41) that form the cross-shaped laser beam (40).

9. The robot tool frame calibration method of claim 5, wherein, The step of moving the robot tool (21) until the end of the robot tool (21) contacts the intersection of the two first laser beams (41) forming the cross-shaped laser beam (40) includes: Move the robot tool (21) until it contacts the intersection of the two first laser beams (41) that form the cross-shaped laser beam (40); Then the robot tool (21) is moved vertically upward until the end of the robot tool (21) leaves the intersection of the two first laser beams (41) that form the cross-shaped laser beam (40); Stop the robot tool (21) from moving and record the coordinates of the first calibration point.

10. The robot tool frame calibration method according to any one of claims 5 to 9, wherein, The step of moving the robot tool (21) until the end of the robot tool (21) is in contact with forming one of the first laser beams (41) of the cross-shaped laser beam (40) comprises moving the robot tool (21) into an area enclosed by a peripheral laser beam (50).

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