TW202406708A - Calibration system for multi-axis robotic arm and definition method of processing coordinates including a platform and measuring devices with adjustable heads for measuring displacement - Google Patents

Abstract

A calibration system for a multi-axis robotic arm is disclosed, which includes a platform, and a first, a second, and a third measuring devices set up on the platform, each equipped with a first, a second, and a third displacement meter, respectively. These displacement meters have a first, a second, and a third measuring heads that can be adjusted to extend in three mutually orthogonal directions to measure displacement in each direction. Through the calibration system, spatial positioning points and calibration coordinates required for calibrating the multi-axis robotic arm can be established. The invention also provides a method for defining the machining coordinates of a multi-axis robotic arm using the calibration system.

Description

Calibration system of multi-axis robotic arm and definition method of processing coordinates

This case is about a correction system, specifically a tool correction system for a multi-axis robot arm, and a method of defining the processing coordinates of a multi-axis robot arm using the aforementioned correction system.

With the rise of Industry 4.0, my country's manufacturing model is gradually moving towards precision and small-volume diversified production. Most automation equipment and precision processing equipment are equipped with multi-axis robotic arms and are used in manufacturing and electronics industry production lines, using the end of multi-axis robotic arms. Equipped with various end tools, such as cutting tools, clamping tools, grinding tools or welding tools, etc., to perform various precision assembly or processing tasks. However, the end tool of the multi-axis robot arm must define an end point, called the Tool Center Pont (hereinafter referred to as TCP). The TCP of the end tool is the same as the end-effect point of the multi-axis robot arm. The displacement amount must be accurately obtained and pre-set. Thus, when the multi-axis robot arm is equipped with an end tool and is running, the controller of the arm can be calibrated according to the obtained displacement amount so that the end point of the end tool The position can accurately run on the path trajectory and position of the action program.

The multi-axis robot arms used in the above industrial applications are mostly articulated multi-axis robot arms, which are highly flexible and suitable for various precision assembly and processing applications. Due to the increasing demand for correction of multi-axis robot arms, it is relatively Increasing attention is paid to the correction quality and errors of multi-axis robotic arms. The calibration method of the multi-axis robot arm is to use the measuring equipment and the multi-axis robot arm to measure and record the same positioning points in a specific direction in the same space in different postures, and send multiple sets of positioning point information back to the machine. The arm controller calculates and obtains the result of the positioning point. Specifically, the above correction method projects the base coordinates (Base Frame, World Frame) of the multi-axis robotic arm to the tool coordinates ( Tool Frame, Tool Center Point) and the processing coordinates of the processing space (User Frame, Part Frame) to complete the correction of the tool coordinates and processing coordinates of the multi-axis robot arm.

At present, in order to facilitate the correction of the TCP of the end tool of a multi-axis robot arm, human judgment or optical measurement methods are mostly used to confirm and measure the positioning point information in the coordinate space; however, judgment by the human eye will vary depending on the operation of different personnel. There are operational errors, and personnel must accumulate the above correction methods several times during the calibration process, generating many sets of anchor point information groups and calculating them through the controller to have objective data or results; if optical tools are used for calibration, traditional tools Most of them are infrared sensors, which are relatively expensive. The conditions of use environment and calibration fixture are more stringent. If the light source of the measurement environment is insufficient or the water mist generated in the environment will cause damage to the lens surface of the optical tool, Water or oil stains may occur, which may lead to malfunction or reduced accuracy. In addition, in order to prevent the measurement of optical instruments from being affected, the surface of the matching calibration fixture needs to be specially processed according to the type of optical instrument, such as ultra-fine micro-matte. Pearl blasting treatment or mirror surface treatment is used to facilitate accurate measurement under various light sources. However, these special treatments will increase the processing cost and storage cost of the calibration fixture. Secondly, if optical instruments such as laser tracking equipment are used for calibration, although the TCP of the end tool of a multi-axis robotic arm can be calibrated quickly and accurately, these optical instruments are not only very expensive to build, but also very expensive to maintain. high.

In view of the above deficiencies, the main purpose of the present invention is to provide a correction system for a multi-axis robotic arm and a method for defining processing coordinates, which is particularly suitable for tool calibration operations of a multi-axis robotic arm, has low cost and can achieve high-precision correction effects. By.

In order to achieve the above object, the present invention provides a calibration system for a multi-axis robotic arm, which includes a platform, a first measuring device, a second measuring device and a third measuring device. The first measuring device is disposed on the platform so that its posture can be adjusted and includes a first displacement meter. The first displacement meter has a first measuring head extending in a first direction for measuring along the A first displacement amount in a first direction; the second measuring device is disposed on the platform so as to adjust its attitude and includes a second displacement meter, the second displacement meter has a second displacement meter extending in a second direction. Two measuring heads are used to measure a second displacement along the second direction, wherein the second direction intersects with the first direction at an intersection point; the third measuring device is arranged to adjust its posture. A third displacement meter is included on the platform, and the third displacement meter has a third measuring head extending in a third direction for measuring a third displacement amount along the third direction, wherein the The third direction passes through the intersection; in particular, the first direction, the second direction and the third direction are orthogonal to each other.

Through the above technical features, the correction system of the multi-axis robot arm provided by the present invention can establish the spatial positioning points and correction coordinates required for the correction of the multi-axis robot arm, so as to facilitate the correction of the tool coordinates and processing coordinates of the multi-axis robot arm, and Compared with manual and optical instrument calibration methods, the calibration system of the present invention can not only be simple to operate and save time, but also significantly reduce the cost of the calibration system, and can be implemented in a wide range of small or large multi-axis robotic arms and various styles. Calibration of end tools.

Preferably, the postures of the first, second and third measuring devices are adjusted such that the first direction, the second direction and the third direction are orthogonal to each other. In this way, the first, second and third measuring heads can form a sensing space to facilitate the correction of tool coordinates and processing coordinates of the multi-axis robot arm.

Preferably, the first displacement meter, the second displacement meter and the third displacement meter can respectively be dial indicators. In this way, by taking advantage of the advantages that the accuracy error of these scales is smaller than the positioning accuracy of the multi-axis robot arm and that the standard measurement tool is reasonably priced and easy to obtain, the calibration system provided by the present invention can be used for the calibration purpose of most multi-axis robot arms. .

Preferably, the correction system of the multi-axis robot arm further includes a base and a rotating shaft, the rotating shaft is pivotally connected between the base and the platform, so that the platform can be positioned around a central axis of the rotating shaft. Rotating relative to the base, the extending direction of the central axis of the rotating shaft passes through the intersection point. Thereby, the user can change the posture of the correction system by rotating the platform, providing the robotic arm with more room for retreat when performing corrections in different postures.

Preferably, the calibration system of the multi-axis robot arm may include a calibration tool with a ball part, the calibration tool is detachably fixed on the platform, the ball part can be connected with the first, second and third measuring The probes are in contact, and the first, second and third displacements measured by the contact of the first, second and third probes are reset to zero, so that the center of the ball part coincides with the intersection point. In this way, before using the calibration system, the calibration tool can be used to calibrate the values and directions measured by the calibration system.

Another object of the present invention is to provide a method for defining the processing coordinates of a multi-axis robot arm using the above correction system. Aiming at a processing plane provided with a workpiece to be processed, a ball tool is installed at the end of an arm and has been calibrated. The multi-axis robot arm with a tool coordinate origin defines the XY plane coordinates of a processing coordinate system of the multi-axis robot arm. The method of defining the processing coordinates includes defining a coordinate origin and an X on the processing plane. Steps a), b) and c) of axial positioning point and a Y-axis positioning point, and using the coordinate origin of the processing coordinate system, the X-axis positioning point and the Y-axis positioning point to complete the multi-axis Step d) of defining the XY plane coordinates of the processing coordinate system of the robot arm. Wherein, the steps a), b) and c) respectively include the following steps: fix the above correction system on the processing plane, select a first, second and third positioning point, and make the first, second and third measuring points The intersection points of the first, second and third directions of the probe coincide with the first, second and third positioning points respectively in the Z-axis direction; the first, second and third measuring probes are calibrated to zero; the multiple The ball tool of the axis robot arm is moved into a sensing space formed by the first, second and third measuring heads and comes into contact with the first, second and third measuring heads; and, the attitude of the ball tool is adjusted until The spherical center of the spherical tool coincides with the intersection point, whereby the multi-axis robot arm defines the coordinate origin, X-axis positioning point and Y-axis positioning point of the processing coordinate system.

Preferably, in the method of defining the processing coordinates of the multi-axis robot arm, the correction system used in steps a), b) and c) is the same correction system. In this way, only one calibration system is needed to perform the above definition method, which can effectively reduce costs.

Preferably, in the method for defining the processing coordinates of the multi-axis robot arm, in steps a), b) and c), whether the center of the sphere of the ball tool coincides with the intersection point is determined by using the multi-axis robot arm. When the ball tool of the axis robot arm comes into contact with the first, second and third measuring heads, it is judged whether the first, second and third measuring heads measure the displacement in the first, second and third directions respectively. In this way, the user can accurately move the position and direction of the multi-axis robot arm through the displacement amounts, so that the center of the ball tool and the intersection point coincide with each other.

Preferably, in steps a), b) and c), a fixed latch is used to fix the first, second and third positioning points respectively, and the extending direction of a central axis of the fixed latch passes through The intersection. In this way, the positions of the first, second and third positioning points can be easily determined.

The detailed structure, features, assembly or usage of the correction system of a multi-axis robotic arm and the method of defining processing coordinates provided by the present invention will be described in the subsequent detailed description of the implementation.

The applicant would like to first explain that in the entire description, including the embodiments introduced below and the claims in the patent application scope, terms related to directionality are based on the direction in the drawings. Secondly, in the embodiments and drawings to be introduced below, the same component numbers represent the same or similar components or structural features.

Please refer to FIG. 1 , which shows a calibration system 20 provided by an embodiment of the present invention being used with a multi-axis robotic arm 10 . In this embodiment, a ball tool 12 having a ball 13 is provided at the end of the multi-axis robot arm 10 , and the ball center 132 of the ball tool 12 is located on an end axis 102 of the multi-axis robot arm 10 . Secondly, the calibration system 20 has a platform 21, a first measuring device 30, a second measuring device 40, and a third measuring device 50. In addition, optionally, the calibration system 20 can be further configured with a base. 60. A rotating shaft 62 is pivotally connected between the base 60 and the platform 21, and a driving member 63 (such as a handle or a driving motor) provided on the rotating shaft 62. By operating the driving member 63 or turning the platform 21, the The platform 21 rotates relative to the base 60 around the central axis of the rotating shaft 62 . Furthermore, the first measuring device 30 is disposed on the platform 21 in an attitude-adjustable manner (described in detail below) and includes a first displacement meter 31 , and the first displacement meter 31 has a first displacement meter 33 extending in a first direction 33 . The first measuring head 35 is used to measure a first displacement along the first direction 33. Similarly, the second and third measuring devices 40 and 50 are respectively arranged on the platform 21 in such a manner that their postures can be adjusted. And respectively include a second and third displacement meter 41, 51, and the second displacement meter 41 has a second measuring head 45 extending in a second direction 43, for measuring a third direction along the second direction 43. and the third displacement meter 51 has a third measuring head 55 extending in a third direction 53 for measuring a third displacement along the third direction 53 . The postures of the first, second, and third measuring devices 30, 40, and 50 can be adjusted so that the second direction 43 intersects the first direction 33 at an intersection 22, and the third direction 53 passes through the intersection 22, that is, The first, second, and third directions 33, 43, and 53 intersect at the aforementioned intersection point 22. During use, the user can use conventional contact and non-contact measuring instruments to adjust and fix the postures of the first measuring device 30 , the second measuring device 40 and the third measuring device 50 so that the first measuring device , the first measuring head 35, the second measuring head 45 and the third measuring head 55 of the second and third displacement meters 31, 41, 51 are spaced apart from each other, and define a ball that can accommodate the multi-axis robot arm 10 The sensing space 18 of the ball part 13 of the tool 12 (as the positioning point space required to calibrate the multi-axis robot arm), and the first, second, and third directions 33, 43, and 53 extend and intersect in a space located in the aforementioned sensing space 18 The intersection point 22. To be more specific, when the calibration system 20 is in use, the first, second and third measuring devices 30, 40 and 50 are adjusted and fixed to specific postures so that the first, second and third displacement meters 31, The extension directions of 41 and 51 are orthogonal to each other, that is, the first direction 33, the second direction 43 and the third direction 53 are orthogonal to each other at the aforementioned intersection 22, and allow the extension direction of the central axis of the rotating shaft 62 disposed below the platform 21 to pass through This intersection point 22 allows the user to change the posture of the entire correction system 20 when the user rotates the platform 21 around the central axis of the rotation axis 62. At this time, the intersection 22 of the extension direction of the central axis of the rotation axis 62 and the correction system 20 can still be Keeping on the same axis, in this way, in addition to ensuring the positioning accuracy of the correction system, it can also provide the ball 13 of the ball tool 12 of the multi-axis robot arm 10 with various postures when entering or exiting the aforementioned sensing space 18. There is more room for concession, that is, when the opening direction of the sensing space 18 provided by the first, second, and third displacement meters 31, 41, and 51 is not conducive to the entry of the ball portion 13 of the ball tool 12 of the multi-axis robot arm 10 When in the aforementioned sensing space 18, the posture of the entire correction system 20 can be changed (change the opening direction of the sensing space 18), so that the ball portion 13 of the ball tool 12 of the multi-axis robot arm 10 can enter the aforementioned sensing space at a convenient angle. In the measurement space 18, in this way, the tool center point of the end tool can be quickly found, and the time for personnel to correct the tool center point can be shortened. Since the usage of the above-mentioned contact and non-contact measuring instruments is the same as that of conventional users, the applicant is not allowed to describe it in detail here.

In addition, regarding the above-mentioned posture adjustment, the first measuring device 30 , the second measuring device 40 and the third measuring device 50 all have a multi-axis fixing frame that can adjust and fix their postures, such as a mechanical magnetic frame. , since the structures and functions of the first measuring device 30 , the second measuring device 40 and the third measuring device 50 are exactly the same, the following only takes the first measuring device 30 as an example to describe its structure, function and its relationship with other devices. The configuration relationship of components.

Specifically, as shown in FIG. 2 , the first measuring device 30 has a support rod 36 fixed on the platform 21 , a universal joint 37 and an extension arm 38 , wherein the universal joint 37 is connected between the support rod 36 and the extension arm 38 . between the extension arms 38, and the end of the extension arm 38 can be fixed to the first displacement meter 31 using a linear slide and a slide rail set or other means. In this way, through the aforementioned universal joint 37, the extension arm 38 can be operated. The relative support rod 36 is moved and fixed at a specific position, thereby changing the posture of the first displacement meter 31 . In this embodiment, the first displacement meter 31 is a dial indicator. However, in other feasible embodiments, the first displacement meter 31 can be an infrared sensing tool or other optical tools, as long as the edge can be measured. The first, second and third displacement amounts of the first direction 33, the second direction 43 and the third direction 53 are sufficient.

Please refer to Figure 2 again. In this embodiment, the calibration system 20 can optionally be configured with a calibration tool 70 having a ball portion 71. The calibration tool 70 can be detachably fixed through various appropriate positioning methods. on the platform 21 of the calibration system 20 . In this way, before or during use of the calibration system 20, the calibration tool 70 can be fixed on the platform 21 of the calibration system 20, and the first measuring device 30, the second measuring device 40 and the third measuring device 50 can be adjusted. The extension arm 38 makes the first measuring head 35 , the second measuring head 45 and the third measuring head 55 extend along the first, second and third directions 33 , 43 and 53 and are orthogonal to each other and the calibration tool 70 The spherical surface of the ball part 71 is in contact, and the first, second, and third displacement meters 31, 41, and 51 are calibrated and reset to zero. At this time, the spherical center 711 of the calibration tool 70 coincides with the intersection point 22 of the calibration system 20, and then the By removing the calibration tool 70 , the calibration and zeroing operation of the values and directions measured before or during use of the calibration system 20 can be completed.

Please refer to FIG. 3 . FIG. 3 is a flow chart for performing tool center point correction on a multi-axis robot arm using the correction system 20 provided by the above embodiment of the present invention. It mainly shows the situation of correction at a first positioning point. As shown in the figure, tool center point correction includes the following steps: As shown in step S1a, the calibration system 20 is fixed at a position that does not move with the multi-axis robot arm; Carry out the calibration and zeroing operation SC of the calibration system 20: first, fix the calibration tool 70 on the platform 21 of the calibration system 20 (as shown in step S1b); secondly, use the calibration method described above to make the calibration system 20 The first measuring head 35, the second measuring head 45 and the third measuring head 55 touch the ball part 71 of the calibration tool 70, and the three components are composed of the first, second and third displacement meters 31, 41 and 51 in orthogonal directions. The read displacement amount is reset to zero (as shown in step S1c); furthermore, as shown in step S1d, the calibration tool 70 is removed from the platform 21, thereby completing the calibration and zeroing operation; As shown in step S1e, the calibration personnel operate the multi-axis robotic arm 10 to drive the end ball tool 12 to move the ball 13 of the ball tool 12 to the above-mentioned position between the first, second, and third measuring heads 35, 45, and 55. In the sensing space 18 formed by the detection tip; Make the center 132 of the ball 13 of the ball tool 12 coincide with the intersection point 22: To achieve this step, the calibration personnel can operate the multi-axis robotic arm 10 to make the ball 13 move slightly in the sensing space 18. At this time, As shown in steps S1f to S1k, when the calibration personnel observe with the naked eye or the computer automatically determines the first, second, and third measuring heads 35, 45 through the output values of the first, second, and third measuring heads 35, 45, and 55, , 55 respectively measure the displacement in the first, second, and third directions 33, 43, and 53 (which can represent the displacement in the X-axis, Y-axis, and Z-axis directions), it means that the center of the ball 132 has not yet reached the intersection point 22 At this time, the calibration personnel can continue to operate the multi-axis robotic arm 10 to make the ball 13 move slightly in the sensing space 18 in a manner that compensates for the previously measured displacement and returns it to zero, until the first, second, and second Until the three-measurement probes 35, 45, and 55 cannot measure the displacement in the first, second, and third directions 33, 43, and 53, it means that the center 132 of the ball tool 12 has coincided with the intersection point 22. It must be noted that there is no order in which the judgment steps S1f, S1h, and S1j are executed. Whichever is performed first or later is acceptable, as long as it is ensured that the first, second, and third measuring heads 35, 45, and 55 measure the first and last values. The displacement in the second and third directions 33, 43, and 53 can be zero; and As shown in step S1m, the position coordinate information of the current posture of the multi-axis robot arm is recorded, that is, the position coordinate information when the multi-axis robot arm 10 drives the end ball tool 12 in the first posture to make the ball center 132 coincide with the intersection point 22 is recorded. information to complete the measurement of the coordinate information of the first positioning point of the tool center point of the multi-axis robotic arm 10.

The above measured first positioning point coordinate information that defines the tool center point of the multi-axis robot arm 10 can be used as the tool center point coordinates of the multi-axis robot arm 10. However, in order to provide higher positioning accuracy, the multi-axis machine can be adjusted The posture of the end ball tool 12 of the arm 10 is used to perform positioning correction of the tool center point coordinates of the multi-axis robot arm 10 in another or more postures. For example, FIG. 4 and FIG. 5 respectively show a flow chart of tool center point correction of a multi-axis robot arm with a second positioning point and a third positioning point. In the correction process disclosed in FIG. 4 and FIG. 5 , when adjusting multiple After steps S2e and S3e of the posture of the multi-axis robot arm, perform steps S2f to S2k and steps S3f to S3k respectively to obtain the coordinate information of the second and third positioning points of the tool center point of the multi-axis robot arm 10, such as steps S2m and S3m shown. In this way, by recording to the controller of the multi-axis robot arm 10 the coordinate information of the first, second and third positioning points measured by the multi-axis robot arm 10 in different postures, the multi-axis robot arm can be defined. The tool center point at the end of 10, as shown in step S3p. It should be noted that the specific contents of the aforementioned steps S2e to S2k and steps S3e to S3k are similar to the above-mentioned steps S1e to S1k, so they will not be described again here.

In the above, the correction system 20 provided by the embodiment of the invention is used to perform TCP correction of the multi-axis robot arm 10, and the coordinates of multiple positioning points at the same position in the same space under different postures of the multi-axis robot arm 10 are used. However, the use of the calibration system 20 provided by the present invention is not limited to TCP calibration of the multi-axis robotic arm 10 . For example, please refer to FIG. 6 . FIG. 6 schematically shows how to use the correction system 20 of the multi-axis robot arm provided by the above embodiment of the present invention to define the processing coordinates of the multi-axis robot arm 10 , that is, using the calibrated tool. The multi-axis robot arm 10 at the center point cooperates with the above-mentioned correction system 20 to define the XY plane coordinates of a processing coordinate system of the multi-axis robot arm 10 . As shown in FIG. 6 , the workpiece 81 to be processed is fixed on a processing plane 82 , and one or three sets of correction systems 20 are used in conjunction with the multi-axis robotic arm 10 for correction. To be more specific, taking the use of three sets of correction systems 20 as an example, each set of correction systems 20 is equipped with a fixed pin 90 for positioning, wherein the central axis extension direction 91 of the fixed pin 90 will pass through the orthogonal intersection point 22 of the correction system 20 , through the fixed pins 90, the three sets of correction systems 20 can be respectively installed at a first positioning point 83 (as the coordinate origin), a second positioning point 85 (as the X-axis positioning point) and a third positioning point 87 (as the Y-axis positioning point), and define the processing coordinates of the multi-axis robot arm 10 as described below.

Specifically, the present invention provides a method for defining the processing coordinates of a multi-axis robotic arm, which is used to target a processing plane 82 provided with a workpiece 81, using a ball tool 13 installed at the end of an arm and calibrated The multi-axis robot arm 10 passing through the tool coordinate origin defines the XY plane coordinates of a processing coordinate system of the multi-axis robot arm 10. The method of defining the processing coordinates mainly includes the following steps: a) on the processing plane 82 Steps of defining a coordinate origin 83 on the above, b) Steps of defining an X-axis positioning point 85 on the processing plane 82, c) Steps of defining a Y-axis positioning point 87 on the processing plane 82 , and d) use the coordinate origin 83 , the X-axis positioning point 85 and the Y-axis positioning point 87 to complete the definition of the XY plane coordinates of the processing coordinate system of the multi-axis robot arm 10 .

Furthermore, FIG. 7 , FIG. 8 and FIG. 9 respectively show the flow chart of how the processing coordinate definition method defines the coordinate origin, X-axis coordinate and Y-axis coordinate of the multi-axis robot arm. Among them, Figure 7 shows step a) of defining a coordinate origin on the processing plane 82, which includes:

Step a1: Select a first positioning point 83 on the processing plane 82 (as the coordinate origin), and fix a correction system 20 on the first positioning point 83 of the processing plane 82 through the pin 90. At this time, the first, second and third The intersection 22 of the first, second and third directions 33, 43 and 53 of the measuring heads 35, 45 and 55 should coincide with the first positioning point 83 in the Z-axis direction. If not, adjust the first and second positioning points 83. And the attitude of the three-measurement probes 35, 45, 55 is such that the intersection point 22 coincides with the first positioning point 83 in the Z-axis direction;

Step a2: Calibrate and reset the first, second and third measuring heads 35, 45 and 55 to re-calibrate the values and directions measured by the calibration system 20. Since it is similar to the SC correction step described in detail above, it will not be described again here;

Step a3: The calibration personnel operate the ball tool 12 of the multi-axis robotic arm 10 to move into a sensing space 18 formed by the first, second and third measuring heads 35, 45 and 55 in the calibration system 20, so that the ball The ball portion 13 of the tool 12 is in contact with the first, second, and third measuring heads 35, 45, and 55; and

Step a4: Adjust the posture of the ball tool 12 until the center 132 of the ball tool 12 coincides with the intersection point 22, that is, perform steps a41 to a46 shown in Figure 7, thereby completing the processing coordinates of the multi-axis robot arm 10 The coordinate origin point 83 of the system is calibrated (ie step a47). Since the aforementioned steps a41 to a46 are similar to the steps S1f to S1k described in detail above, they will not be described again.

Similarly, FIG. 8 shows step b) of defining an X-axis positioning point on the machining plane 82, and FIG. 9 shows step c) of defining a Y-axis positioning point on the machining plane 82. Steps b1 to b4 (including b41 to b47) and steps c1 to c4 (including c41 to c47) shown in Figures 8 and 9 are similar to the steps shown in Figure 7 and will not be described again here. Finally, in step d in Figure 9 , using the coordinates of the coordinate origin, the coordinates of the X-axis positioning point, and the coordinates of the Y-axis positioning point, the XY plane of the processing coordinate system of the multi-axis robot arm 10 can be completed. Definition of coordinates. It must be noted that the controllers of various brands of robotic arms currently used in commercial applications will automatically generate Z-axis coordinates. Therefore, combined with the aforementioned XY plane coordinates, the XYZ coordinates of the complete processing coordinate system can be defined.

It is worth mentioning that in the above-mentioned steps a), b) and c), whether the center 122 of the ball tool 12 coincides with the intersection point 22 depends on the use of the multi-axis robot arm 10 and the ball tool 12. When the first measuring head 35 , the second measuring head 45 and the third measuring head 55 are in contact, whether the first measuring head 35 , the second measuring head 45 and the third measuring head 55 respectively measure the first direction. 33. The first displacement amount, the second displacement amount and the third displacement amount in the second direction 43 and the third direction 53 are judged by adjusting the posture of the multi-axis robot arm 10 until the first displacement amount, the second displacement amount When the values of the displacement amount and the third displacement amount gradually become smaller and approach zero, it can be judged that the center 122 of the ball tool 12 has coincided with the orthogonal intersection point 22 .

Secondly, the definition method 80 of the processing coordinates fixes the correction system 20 at a position that does not move with the multi-axis robot arm 10 and is located on the same processing plane 82. Therefore, the structural design of the correction system 20 of the present invention The weight of the multi-axis robot arm 10 is not limited to a specific configuration, and can be used in a wide range of specifications and different styles from small to large-scale multi-axis robot arms, thereby achieving the diverse applicability of the correction system 20 of the present invention.

In addition, the calibration system 20 mentioned in step a), step b) and step c) in the second embodiment of the present invention can be the same calibration system. To further illustrate, the user can calibrate the accuracy of the workpiece 81 as needed. Or the allowable error size of the measurement tool is used to determine whether the workpiece 81 to be processed needs to use three correction systems 20 to execute the method 80 of defining the processing coordinates, and it does not exclude the simultaneous execution of the above step a) by the three correction systems 20. , step b) and step c).

To sum up, the calibration system of the multi-axis robotic arm provided by the present invention not only has a simple structure, but also can provide the spatial positioning points and calibration coordinates required to calibrate the multi-axis robotic arm 10, which is helpful for the multi-axis robotic arm 10. Calibration of tool coordinates and processing coordinates; in addition, the operation mode can be switched according to needs, and the user can manually confirm the measurement results of each measuring head of the calibration system 20 and use it as a basis for judging the movement direction of the multi-axis robot arm 10 , or the first, second, and third measuring heads 35, 45, and 55 of the calibration system 20 respectively measure the displacements in the first, second, and third directions 33, 43, and 53, and the displacement results are returned It is transmitted to the computer or logic controller for automatic judgment to facilitate the user to operate the multi-axis robot arm 10; and compared with the traditional manual and optical instrument calibration methods, the calibration system of the present invention can be easily operated and save time, and can also significantly The purpose of the present invention is achieved by reducing the cost of the calibration system and being able to implement calibration operations on a wide range of small or large multi-axis robotic arms and various types of end tools.

Finally, it must be stated again that those with ordinary knowledge in the field of the present invention should be able to understand that these detailed descriptions and specific examples for implementing the present invention are only suitable for illustrating the present invention and are not intended to limit the patent application of the present invention. The substitution or change of other equivalent components shall also be covered by the patentable scope of the present invention.

10:Multi-axis robotic arm 102:Terminal axis 12: Ball tool 13: Ball Club 132: center of ball 18: Sensing space 20:Calibration system 21:Platform 22: Orthogonal intersection point 30: First measuring device 31: The first displacement meter 33:First direction 35: First measuring probe 36:Support rod 37:Universal joint 38:Extended arm 40: Second measuring device 41: Second displacement meter 43:Second direction 45: Second measuring head 50: The third measuring device 51: The third displacement meter 53:Third direction 55: The third measuring head 60: base 62:Rotating axis 63:Driving parts 70:Calibration tools 71: Ball Club 711: center of ball 81: Parts to be processed 82: Processing plane 83: First positioning point (coordinate origin) 85: Second positioning point (X-axis positioning point) 87: Third positioning point (Y-axis positioning point) 90:Fixed latch 91:Central axis S1a～S1m,SC: steps S2e～S2m: steps S3e～S3p: steps a1～a4, a41～a47: steps b1～b4, b41～b47: steps c1～c4,c41～c47,d: step

FIG. 1 is a schematic diagram of a multi-axis robot arm correction system and a multi-axis robot arm provided by an embodiment of the present invention. FIG. 2 is a schematic diagram of a calibration tool installed in the calibration system of the multi-axis robotic arm provided by the above embodiment of the present invention. FIG. 3 is a flow chart of using the calibration system of the multi-axis robot arm provided by the above embodiment of the present invention to perform the tool center point calibration of the multi-axis robot arm, showing the situation of a first positioning point being calibrated. Figure 4 is a flow chart of using the calibration system of the multi-axis robot arm provided by the above embodiment of the present invention to perform the tool center point correction of the multi-axis robot arm, showing the situation of performing correction at a second positioning point. FIG. 5 is a flow chart of using the correction system of the multi-axis robot arm provided by the above embodiment of the present invention to perform the tool center point correction of the multi-axis robot arm, showing the situation of performing correction at a third positioning point. FIG. 6 is a schematic diagram showing how to define the processing coordinates of the multi-axis robot arm using the correction system of the multi-axis robot arm provided by the above embodiment of the present invention. FIG. 7 is a flow chart showing how to use the correction system of the multi-axis robot arm provided by the above embodiment of the present invention to define the coordinate origin of the processing coordinates of the multi-axis robot arm. FIG. 8 is a flow chart showing how to use the correction system of the multi-axis robot arm provided by the above embodiment of the present invention to define the X-axis coordinate of the processing coordinate of the multi-axis robot arm. FIG. 9 is a flow chart showing how to use the correction system of the multi-axis robot arm provided by the above embodiment of the present invention to define the Y-axis coordinate of the processing coordinate of the multi-axis robot arm.

10:Multi-axis robotic arm

102:Terminal axis

12: Ball tool

13: Ball Club

132: center of ball

18: Sensing space

20:Calibration system

21:Platform

22: Orthogonal intersection point

30: First measuring device

31: The first displacement meter

33:First direction

35: First measuring probe

40: Second measuring device

41: Second displacement meter

43:Second direction

45: Second measuring head

50: The third measuring device

51: The third displacement meter

53:Third direction

55: The third measuring head

60: base

62:Rotating axis

63:Driving parts

Claims (9)

A correction system for a multi-axis robotic arm, including: a platform; A first measuring device is arranged on the platform in an adjustable manner and includes a first displacement meter. The first displacement meter has a first measuring head extending in a first direction for measuring. a first displacement amount along the first direction; A second measuring device is arranged on the platform in an adjustable manner and includes a second displacement meter. The second displacement meter has a second measuring head extending in a second direction for measuring. a second displacement amount along the second direction, wherein the second direction intersects the first direction at an intersection point; and A third measuring device is arranged on the platform in an adjustable manner and includes a third displacement meter. The third displacement meter has a third measuring head extending in a third direction for measuring. A third amount of displacement along the third direction, wherein the third direction passes through the intersection point. The calibration system of a multi-axis robot arm as claimed in claim 1, wherein the postures of the first, second and third measuring devices are adjusted so that the first direction, the second direction and the third direction are orthogonal to each other. pay. As claimed in claim 1, the correction system of the multi-axis robot arm, wherein the first displacement meter, the second displacement meter and the third displacement meter are respectively micrometers. The correction system of the multi-axis robotic arm as described in claim 1 further includes a base and a rotating shaft, the rotating shaft is pivotally connected between the base and the platform, so that the platform can rotate around a central axis of the rotating shaft When rotating relative to the base, the extending direction of the central axis of the rotating shaft passes through the intersection point. The correction system of the multi-axis robot arm as described in claim 1 further includes a correction tool having a ball part, the correction tool is detachably fixed on the platform, so that the center of the ball part coincides with the intersection point , and the ball part can be in contact with the first measuring head, the second measuring head and the third measuring head. A method of defining the processing coordinates of a multi-axis robot arm is used to target a processing plane provided with a workpiece to be processed, using a multi-axis robot arm equipped with a spherical tool at the end of an arm and the origin of the tool coordinates has been corrected, Define the XY plane coordinates of a processing coordinate system of the multi-axis robot arm. The method of defining the processing coordinates includes the following steps: a) The steps to define a coordinate origin on the processing plane include: a1) Fix a correction system as described in claim 2 on the processing plane to select a first positioning point, and make the intersection of the first, second and third directions of the first, second and third measuring heads, Coincident with the first positioning point in a Z-axis direction; a2) Calibrate and reset the first, second and third measurement probes to zero; a3) Displace the ball tool of the multi-axis robot arm into a sensing space formed by the first, second and third measuring heads to contact the first, second and third measuring heads; and a4) Adjust the posture of the spherical tool until the center of the spherical tool coincides with the intersection point, whereby the multi-axis robot arm defines the coordinate origin of the processing coordinate system; b) The steps to define an X-axis positioning point on the processing plane include: b1) Fix a correction system as described in request item 2 on the processing plane to select a second positioning point, and make the intersection of the first, second and third directions of the first, second and third measuring heads, Coincident with the second positioning point in a Z-axis direction; b2) Calibrate and reset the first, second and third measurement probes to zero; b3) Displace the ball tool of the multi-axis robot arm into a sensing space formed by the first, second and third measuring heads to contact the first, second and third measuring heads; and b4) Adjust the posture of the spherical tool until the center of the spherical tool coincides with the intersection point, whereby the multi-axis robot arm defines the X-axis positioning point of the processing coordinate system; c) The steps to define a Y-axis positioning point on the processing plane include: c1) Fix a correction system as described in claim 2 on the processing plane to select a third positioning point, and make the intersection of the first, second and third directions of the first, second and third measuring heads, Coincident with the third positioning point in a Z-axis direction; wherein a line connecting the third positioning point and the first positioning point is orthogonal to a line connecting the second positioning point and the first positioning point; c2) Calibrate and reset the first, second and third measuring probes to zero; c3) Displace the ball tool of the multi-axis robot arm into a sensing space formed by the first, second and third measuring heads to contact the first, second and third measuring heads; and c4) Adjust the posture of the spherical tool until the center of the spherical tool coincides with the intersection point, whereby the multi-axis robot arm defines the Y-axis positioning point of the processing coordinate system; and d) Use the coordinate origin of the processing coordinate system, the X-axis positioning point and the Y-axis positioning point to complete the definition of the XY plane coordinates of the processing coordinate system of the multi-axis robot arm. The method for defining processing coordinates as described in claim 6, wherein the correction system used in step a), step b) and step c) is the same correction system. The method for defining processing coordinates as described in claim 6, wherein in steps a), step b) and step c), whether the center of the sphere of the ball tool coincides with the intersection point is determined by using the multi-axis robot arm. When the ball tool is in contact with the first, second and third measuring heads, it is judged whether the first, second and third measuring heads measure the displacement in the first, second and third directions respectively. The method for defining processing coordinates as described in claim 6, wherein the correction system used in step a) has a fixed pin, the extending direction of a central axis of the fixed pin passes through the intersection point of the correction system, and the fixed pin The bolt lock is fixed at the first positioning point, or the correction system used in step b) has a fixed bolt, the extending direction of a central axis of the fixed bolt passes through the intersection point of the correction system, and the fixed bolt lock is fixed At the second positioning point, or the correction system used in step c), there is a fixed bolt, the extending direction of a central axis of the fixed bolt passes through the intersection point of the correction system, and the fixed bolt is locked on the third Three anchor points.