Processing system, robot system, control device, teaching method, program, and storage medium

Abstract

To provide a processing system, a robot system, a control unit, a teaching method, a program, and a storage medium with which a teaching point can be simply set.SOLUTION: A robot includes a detector that includes a plurality of detection elements arranged along a first direction and a second direction intersecting the first direction, and a manipulator that is attached with the detector. A processing system causes the detector to execute an investigation to perform transmission of an ultrasonic wave and detection of a reflected wave for a welded part of a joined body, and calculates a center position of the welded part on a first surface along the first direction and the second direction on the basis of first intensity data indicating intensity of the reflected wave obtained through the investigation. When a distance between the center position and a first position of the detector on the first surface is equal to or less than a first threshold, the processing system sets a teaching point of the robot on the basis of, the first position. When the distance exceeds the first threshold, the processing system moves the detector to a second position along the first surface to reduce the distance and sets the teaching point on the basis of, the second position.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] An embodiment of the present invention relates to a processing system, a robot system, a control device, a teaching method, a program, and a storage medium. [Background technology]

[0002] There is a robot that inspects joints. There is a demand for a technology that can more easily set teaching points for this robot during inspection. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-278809 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a processing system, a robot system, a control device, a teaching method, a program, and a storage medium that enable teaching points to be set more easily. [Means for solving the problem]

[0005] A processing system according to an embodiment teaches an operation to a robot. The robot includes a detector including a plurality of detection elements arranged along a first direction and a second direction intersecting the first direction, and a manipulator to which the detector is attached. The processing system causes the detector to perform an exploration of a welded portion of a joint by transmitting ultrasonic waves and detecting reflected waves. The processing system calculates a center position of the welded portion on a first surface along the first direction and the second direction based on first intensity data indicating the intensity of the reflected waves obtained by the exploration. When a distance between the center position and a first position of the detector on the first surface is equal to or less than a first threshold value, the processing system sets a teaching point of the robot based on the first position. When the distance exceeds the first threshold value, the processing system moves the detector to a second position along the first surface so as to reduce the distance, and sets the teaching point based on the second position. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic diagram illustrating a robot system according to an embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing the structure of a detector and a joint body. [Diagram 3] 1A and 1B are schematic diagrams for explaining the operation of a processing system according to an embodiment. [Figure 4] FIG. 13 is a schematic diagram illustrating intensity data obtained by exploration. [Diagram 5] 4 is a flowchart illustrating a teaching method according to the embodiment. [Figure 6] FIG. 4 is a schematic diagram showing the intensity distribution of a reflected wave obtained by processing the intensity data. [Figure 7] FIG. 4 is a schematic diagram illustrating an identified welded portion. [Figure 8] 13 is a flowchart showing a teaching method according to a first modified example of the embodiment. [Figure 9] FIG. 2 is a schematic diagram showing a detector. [Figure 10] 1 is an example of an image obtained during an inspection. [Figure 11] FIG. 4 is a schematic diagram showing the intensity distribution of a reflected wave. [Figure 12] 13 is a flowchart showing a teaching method according to a second modified example of the embodiment. [Figure 13] FIG. 11 is a schematic diagram for explaining a teaching method according to a second modified example of the embodiment. [Figure 14] 4 is a flowchart showing an inspection process according to the embodiment. [Figure 15] FIG. 13 is a schematic diagram showing the structure of another detector. [Figure 16] FIG. 2 is a schematic diagram showing a hardware configuration. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as those in reality. Even when the same part is shown, the dimensions and ratios of each part may be different depending on the drawing. In this specification and each drawing, elements similar to those already explained are given the same reference numerals and detailed explanations are omitted as appropriate.

[0008] FIG. 1 is a schematic diagram showing a robot system according to an embodiment. 1, a robot system 2 according to the embodiment includes a processing system 1 and a robot 20. The processing system 1 includes a control device 10, an operation terminal 11, and a processing device 12. The processing system 1 teaches the robot 20 an operation.

[0009] The control device 10 controls the operation of the robot 20. The control device 10 is a so-called robot controller. The control device 10 includes a control circuit, a servo control unit, a power supply unit, etc. The control device 10 controls the operation of the robot 20 by controlling the servo motors of each axis according to a pre-stored operation program, teaching data set by an operation terminal 11, etc.

[0010] The operation terminal 11 is a terminal device for operating the robot 20. The operation terminal 11 is a so-called teaching pendant. The operation terminal 11 is connected to the control device 10, and accepts input of an operation program for the robot 20, input of settings, etc. Furthermore, a user can use the operation terminal 11 to change, modify, or newly create teaching data. The teaching data is data for teaching the robot 20 the operation of the robot 20.

[0011] The robot 20 includes a manipulator 21 and a detector 22 attached to the manipulator 21. For example, the manipulator 21 is a vertical multi-joint type. The detector 22 is provided at the tip of the manipulator 21 as an end effector. The manipulator 21 may be a horizontal multi-joint type or a parallel link type. The manipulator 21 may include a combination of two or more types selected from the vertical multi-joint type, the horizontal multi-joint type, and the parallel link type. The manipulator 21 preferably has six or more degrees of freedom.

[0012] The detector 22 performs probing of the target. The probing involves transmitting ultrasonic waves toward the target and detecting (receiving) the reflected waves. The detector 22 obtains intensity data indicating the intensity of the reflected waves through the probing. The detector 22 transmits the intensity data to the processing device 12.

[0013] 1, a dispenser 25 is further provided as an end effector. The dispenser 25 dispenses couplant liquid onto a target surface.

[0014] The target of the exploration is a joint in which a plurality of members are joined by welding. The plurality of members are joined at a welded portion. The processing device 12 processes the strength data and acquires data related to the welded portion. For example, the processing device 12 executes an inspection process on the welded portion using the strength data. The robot system 2 executes the inspection process on each of a plurality of joints 50 of the same type.

[0015] FIG. 2 is a schematic diagram showing the structure of the detector and the bonded body. In the example of FIG. 2, the target of detection by detector 22 is a joined body 50. Joined body 50 includes a metal plate 51 (first member) and a metal plate 52 (second member). Metal plate 51 and metal plate 52 are joined at a welded portion 53. That is, in welded portion 53, there is no boundary surface between metal plate 51 and metal plate 52. In welded portion 53, there is a solidified portion 54 formed by mixing of molten metals. Welded portion 53 is formed by resistance spot welding.

[0016] As shown in FIG. 2, the detector 22 includes a detection element 22a, a propagation portion 22b, a housing 22c, and a sensor 22d.

[0017] The detection elements 22a are two-dimensionally arranged along the X direction (first direction) and the Y direction (second direction). The X direction and the Y direction intersect with each other. In this example, the Y direction is perpendicular to the X direction. For example, the detection elements 22a are transducers and emit ultrasonic waves with a frequency of 1 MHz or more and 100 MHz or less. The detection elements 22a transmit ultrasonic waves along the Z direction (third direction). The Z direction is perpendicular to the XY plane (first plane).

[0018] The multiple detection elements 22a are provided at the tip of the housing 22c and are covered by the propagation part 22b. When the detector 22 is brought into contact with the joint 50, the propagation part 22b is located between the detection elements 22a and the joint 50. When the detection elements 22a emit ultrasonic waves, the ultrasonic waves propagate through the propagation part 22b and are transmitted to the outside of the detector 22. When the ultrasonic waves are reflected, the reflected waves propagate through the propagation part 22b and reach the detection elements 22a.

[0019] The detection element 22a detects the reflected wave. The intensity of the signal detected by the detection element 22a corresponds to the intensity of the reflected wave. The detector 22 obtains a signal (intensity data) indicating the reflected wave intensity and transmits it to the processing device 12.

[0020] The propagation part 22b is made of a resin material through which ultrasonic waves can easily propagate. The propagation part 22b can suppress deformation, damage, etc. of the detection element 22a when the detector 22 comes into contact with the welded part 53. The propagation part 22b has sufficient hardness to suppress deformation, damage, etc. when it comes into contact with the welded part 53.

[0021] The sensor 22d is attached to the housing 22c, and detects contact of the detector 22 with the joint 50. The sensor 22d is, for example, a force sensor, an acceleration sensor, an angular velocity sensor, a light blocking sensor, or a distance measuring sensor.

[0022] During the inspection, a couplant liquid 55 is applied to the surface of the bonded body 50 so that ultrasonic waves can easily propagate between the detector 22 and the bonded body 50. Each of the detection elements 22a transmits ultrasonic waves US toward the bonded body 50 to which the couplant liquid 55 has been applied.

[0023] For example, as shown in Fig. 2, one detection element 22a transmits ultrasonic waves US toward the bonded body 50. A part of the ultrasonic waves US is reflected by the upper or lower surface of the bonded body 50. Each of the multiple detection elements 22a detects the reflected waves RW. In the inspection, each detection element 22a transmits ultrasonic waves US in sequence, and each reflected wave RW is detected by the multiple detection elements 22a.

[0024] The processing device 12 executes various processes using the strength data. For example, the processing device 12 inspects the welded portion 53. The processing device 12 may identify the position of the welded portion 53 in the joined body 50. The processing device 12 may calculate the center position of the welded portion 53. The processing device 12 may calculate the diameter of the welded portion 53.

[0025] 3(a) to 3(c) are schematic views for explaining the operation of the processing system according to the embodiment. As shown in FIG. 3( a ), the ultrasonic wave US is reflected by the surface of the propagation portion 22 b , the upper surface 51 a and the lower surface 51 b of the metal plate 51 , and the upper surface 53 a and the lower surface 53 b of the welded portion 53 .

[0026] The positions in the Z direction of the surfaces of the propagation portion 22b, the upper surface 51a, the upper surface 53a, the lower surface 51b, and the lower surface 53b are different from one another. That is, the distances in the Z direction between these surfaces and the detection element 22a are different from one another. When the detection element 22a detects the reflected waves from these surfaces, peaks of the reflected wave intensity are detected. After transmitting the ultrasonic wave US, the time until each peak is detected is calculated, thereby making it possible to determine from which surface the ultrasonic wave US is reflected.

[0027] Each of FIG. 3(b) and FIG. 3(c) is a graph illustrating the relationship between the time after transmitting ultrasonic waves US and the intensity of the reflected wave RW at one point in the XY plane. In FIG. 3(b) and FIG. 3(c), the horizontal axis represents the intensity of the detected reflected wave RW. The vertical axis represents the elapsed time after transmitting ultrasonic waves US. The time corresponds to the position in the Z direction. The graph of FIG. 3(b) illustrates the detection result of the reflected wave RW from the surface, upper surface 51a, and lower surface 51b of the propagation part 22b. That is, the graph of FIG. 3(b) illustrates the detection result of the reflected wave RW from a point that is not joined. The graph of FIG. 3(c) illustrates the detection result of the reflected wave RW from the surface, upper surface 53a, and lower surface 53b of the propagation part 22b. That is, the graph of FIG. 3(c) illustrates the detection result of the reflected wave RW from a point that is joined.

[0028] 3(b) and 3(c), peak Pe10 is based on the reflected wave RW from the surface of the propagation portion 22b. Peak Pe11 is based on the reflected wave RW from the upper surface 51a. Peak Pe12 is based on the reflected wave RW from the lower surface 51b. The times from the transmission of the ultrasonic wave US to the detection of peak Pe11 and peak Pe12 correspond to the positions in the Z direction of the upper surface 51a and lower surface 51b, respectively.

[0029] Similarly, peak Pe13 is based on the reflected wave RW from the upper surface 53a. Peak Pe14 is based on the reflected wave RW from the lower surface 53b. The times from the transmission of the ultrasonic wave US to the detection of peaks Pe13 and Pe14 correspond to the positions of the upper surface 53a and the lower surface 53b in the Z direction, respectively.

[0030] The processing device 12 determines whether or not a peak Pe12 exists in the reflected wave intensity distribution in the Z direction at each point in the XY plane. Specifically, the processing device 12 detects a peak in a range in the Z direction in which the peak Pe12 can be detected. The processing device 12 compares the peak intensity with a threshold value. The range in the Z direction and the threshold value are set in advance.

[0031] If the peak intensity exceeds the threshold value, the processing device 12 determines that the peak is peak Pe12. The presence of peak Pe12 indicates that a lower surface 51b exists at that point, and that the metal plates 51 and 52 are not joined. The processing device 12 determines that the points at which peak Pe12 is detected are not joined. The processing device 12 determines that the points at which peak Pe12 is not detected are joined. The processing device 12 sequentially determines whether each point in the XY plane is joined. The processing device 12 identifies a set of points determined to be joined as a welded portion 53.

[0032] For example, in the inspection process, the processing device 12 identifies the welded portion 53 and calculates the diameter of the welded portion 53. The processing device 12 compares the diameter with a preset threshold value. If the diameter exceeds the threshold value, the processing device 12 determines that the welded portion 53 is acceptable. If the diameter is equal to or smaller than the threshold value, the processing device 12 determines that the welded portion 53 is unacceptable. The diameter compared with the threshold value is the major diameter or minor diameter of the welded portion 53.

[0033] In the examples of FIG. 3(b) and FIG. 3(c), the intensity of the reflected wave RW is expressed as an absolute value. The intensity of the reflected wave may be expressed in any manner. For example, the reflected wave intensity output from the detection element 22a includes positive and negative values ​​depending on the phase. Various processes may be performed based on the reflected wave intensity including positive and negative values. The reflected wave intensity including positive and negative values ​​may be converted to an absolute value. The average value of the reflected wave intensity may be subtracted from the reflected wave intensity at each time. Alternatively, the weighted average value, weighted moving average value, etc. of the reflected wave intensity may be subtracted from the reflected wave intensity at each time. Filtering may be performed so that only frequency components of a specific period are extracted. Even when the results of applying these processes to the reflected wave intensity are used, the various processes described in the present application can be performed.

[0034] FIG. 4 is a schematic diagram illustrating intensity data obtained by the exploration. In the exploration, as described above, each detection element 22a sequentially transmits ultrasonic waves, and the reflected waves are detected by the multiple detection elements 22a. In the specific example shown in FIG. 2, 8×8, or 64, detection elements 22a are provided. In this case, the 64 detection elements 22a sequentially transmit ultrasonic waves. Each detection element 22a repeatedly detects the reflected wave 64 times. A detection result of the reflected wave intensity distribution in the Z direction is output 64 times from one detection element 22a. The intensity distributions of the 64 reflected waves output from one detection element 22a are summed. The summed intensity distribution becomes the intensity distribution at the coordinates where one detection element 22a is provided in one exploration. The same process is performed on the detection results by each of the 64 detection elements 22a. Aperture synthesis may be performed on the detection results of each detection element 22a in order to improve the resolution in the X and Y directions. By the above process, the intensity distribution of the reflected wave in the Z direction is generated at each point in the XY plane (first plane). That is, three-dimensional intensity data including the reflected wave intensity at each point in the X, Y, and Z directions is obtained.

[0035] Fig. 4 shows a schematic diagram of the three-dimensional intensity distribution. The schematic diagram of Fig. 4 shows the state of the vicinity of the welded part 53 in the three-dimensional intensity data. In Fig. 4, the parts with high brightness are parts where the reflected wave intensity of the ultrasonic waves is relatively high. In the example of Fig. 4, reflected waves from the upper and lower surfaces of the welded part 53 and reflected waves that are multiple-reflected between these upper and lower surfaces appear.

[0036] When obtaining data on a welded portion in the inspection process, the control device 10 operates the manipulator 21 so that the tip of the detector 22 comes into contact with the welded portion 53. The position and orientation of the tip of the detector 22 when exploration is performed in the inspection process is set in advance as a teaching point. The position and orientation of another part corresponding to the position and orientation of the tip of the detector 22 may also be set as a teaching point. In this case, too, the position and orientation of the tip of the detector 22 can be considered to be set as a teaching point.

[0037] The control device 10 operates the manipulator 21 according to an operation program so that the position and orientation of the tip of the detector 22 are set to the position and orientation of the teaching point. Specifically, the control device 10 acquires data indicating the rotation angle of each actuator from an encoder provided at each joint of the manipulator 21. The control device 10 generates a control signal based on the stored teaching point and the acquired data. The control device 10 transmits the generated control signal to the robot 20, and moves the manipulator 21 by operating each actuator.

[0038] The processing system 1 according to the embodiment teaches an operation to the robot 20. The processing system 1 can be used to set teaching points of the robot 20. The processing system 1 uses intensity data transmitted from the detector 22 to set the teaching points.

[0039] FIG. 5 is a flowchart showing a teaching method according to the embodiment. The user brings the tip of the detector 22 close to the welded portion 53. Couplant liquid is applied to the welded portion 53. The detector 22 comes into contact with the welded portion 53 (step S1). For example, the user moves the manipulator 21 by hand or using the operation terminal 11 to bring the tip of the detector 22 into contact with the welded portion 53. Alternatively, after the user brings the detector 22 close to the welded portion 53, the control device 10 may move the manipulator 21 to bring the detector 22 into contact with the welded portion 53. The processing system 1 executes a position teaching process (step S10).

[0040] In the position teaching process, the processing device 12 causes the detector 22 to perform an exploration while the detector 22 is in contact with the welded portion 53 (step S11). The detector 22 acquires intensity data (first intensity data) indicating the intensity of the reflected wave by the exploration (step S12). The processing device 12 receives the intensity data from the detector 22. The processing device 12 calculates the center position of the welded portion 53 on the XY plane based on the intensity data (step S13). The processing device 12 transmits the center position to the control device 10. The control device 10 refers to the position (first position) of the detector 22 on the XY plane. The control device 10 compares the distance between the received center position and the first position with a preset threshold value (first threshold value) (step S14).

[0041] For example, the position of detector 22 on the XY plane corresponds to the center position of the intensity data on the XY plane. In this case, the center position of welded portion 53 calculated based on the intensity data corresponds to the distance between the center position of welded portion 53 and the center position of the intensity data on the XY plane. Therefore, in step S14, control device 10 compares the received center position of welded portion 53 with a preset threshold value (first threshold value).

[0042] If the distance is equal to or less than the threshold, the control device 10 sets the teaching point based on the first position (step S15). For example, the control device 10 sets the first position as the position of the teaching point. The control device 10 may set a position obtained by calculation for the first position as the position of the teaching point.

[0043] If the distance exceeds the threshold, the control device 10 moves the detector 22 along the XY plane so as to decrease the distance (step S16). At this time, the control device 10 may move the detector 22 away from the joined body 50 to avoid friction between the detector 22 and the joined body 50. After moving the detector 22 away from the joined body 50, the control device 10 moves the detector 22 along the XY plane. Then, the control device 10 brings the detector 22 into contact with the joined body 50.

[0044] The control device 10 refers to the position (second position) of the detector 22 on the XY plane after the movement. The control device 10 sets the teaching point based on the second position (step S17). For example, the control device 10 sets the second position as the position of the teaching point. The control device 10 may set a position obtained by calculation for the second position as the position of the teaching point.

[0045] The control device 10 may execute step S14 again after step S16. In this case, the distance between the center position and the position of the detector 22 is compared with the threshold again. Step S16 is repeated until the distance becomes equal to or less than the threshold. This allows the position of the teaching point to be set more appropriately. The control device 10 saves the set teaching point (step S18).

[0046] The XYZ coordinate system shown in Fig. 2 may be different from the robot coordinate system used to express the teaching point. The control device 10 or the processing device 12 may convert the center position calculated in step S13 into the robot coordinate system as appropriate. When setting the teaching point, the control device 10 or the processing device 12 may convert the position of the detector 22 on the XY plane into the robot coordinate system as appropriate.

[0047] A method for calculating the center position of welded portion 53 in the above teaching method will be described below. The center position can be calculated using any of the following methods.

[0048] 6(a) to 6(c) are schematic diagrams showing the intensity distribution of the reflected wave obtained by processing the intensity data. Processing device 12 processes the intensity data to obtain the data shown in Figures 6(a) to 6(c). Figure 6(a) shows the intensity distribution of the reflected wave in the XY plane near welded portion 53. Figure 6(b) shows the intensity distribution of the reflected wave in the YZ plane near welded portion 53. Figure 6(c) shows the intensity distribution of the reflected wave in the XZ plane near welded portion 53.

[0049] The data in FIG. 6(a) is obtained by adding up the intensities in the Z direction at each point on the XY plane. The data in FIG. 6(b) is obtained by adding up the intensities in the X direction at each point in the Z direction. The data in FIG. 6(c) is obtained by adding up the intensities in the Y direction at each point in the Z direction. In FIG. 6(a) to FIG. 6(c), the intensity of the reflected wave is shown in a schematic binarized form. A white point indicates that the intensity of the reflected wave at that point is relatively high. A black point indicates that the intensity of the reflected wave at that point is relatively low.

[0050] For example, the processing device 12 calculates the position of the center of intensity for the intensity distribution of the reflected wave on the XY plane shown in Fig. 6(a) as the center position of the welded part 53. For example, as shown in Fig. 6(a), the position of the center of intensity may be calculated for a binarized image. Alternatively, the position of the center of intensity may be calculated for an image in which each pixel has a pixel value of three or more levels (for example, 0 to 255).

[0051] Alternatively, the processing device 12 may extract the reflected wave component from the welded portion 53 in the Z direction and calculate the center of gravity position. For example, as shown in Figs. 6(b) and 6(c), the period in which the reflected wave from the welded portion 53 is detected is different from the period in which the reflected wave from other portions is detected. The processing device 12 filters the intensity distribution in the Z direction using a preset thickness of the welded portion 53. In this way, the processing device 12 extracts the reflected wave component from the welded portion 53. The processing device 12 calculates the center of gravity position of the intensity distribution in the XY plane after filtering as the center position of the welded portion 53.

[0052] Alternatively, the processing device 12 may identify the welded portion 53 and calculate the center position based on the identified welded portion 53.

[0053] FIG. 7 is a schematic diagram illustrating the identified welded portion. FIG. 7 shows the result of the determination of whether each point is bonded or not bonded at each point on the XY plane where the search is performed. The range in the X direction and the Y direction of the region where the determination of whether the bonded or not bonded is performed corresponds to the range in the X direction and the Y direction where the strength data is obtained. As an example, the range in the X direction and the Y direction of the two-dimensional data shown in FIG. 7 correspond to the range in the X direction and the Y direction of the three-dimensional strength data shown in FIG. 4, respectively. A part of the range where the strength data is obtained in the X direction and the Y direction may be extracted, and the determination of whether the bonded or not bonded may be performed for the extracted region. In FIG. 7, the points determined to be bonded based on the strength data are shown in white. The points determined to be not bonded are shown in black. A set of points determined to be bonded is specified as the welded portion 53. The processing device 12 generates the two-dimensional data shown in FIG. 7 using the determination result of the bond at each point.

[0054] The processing device 12 may calculate the position of the center of gravity of the identified welded portion 53 on the XY plane as the center position of the welded portion 53. As described above, the welded portion 53 can be identified by determining whether each point on the XY plane is joined or unjoined. The processing device 12 may calculate the center of a circle inscribed or circumscribed on the XY plane for the identified welded portion 53 as the center position of the welded portion 53.

[0055] Once the teaching point is set, the robot system 2 thereafter executes an inspection process using the teaching point. For example, the robot system 2 refers to the teaching point and executes an inspection process for a welded portion 53 of another joined body 50. When executing the inspection process, the control device 10 moves the manipulator 21 and sets the position and orientation of the tip of the detector 22 to the position and orientation of the teaching point.

[0056] When a plurality of welds 53 are formed in one joined body 50, teaching points are set for each of the welds 53. After the plurality of teaching points are set, inspection processing is performed on each of the plurality of welds 53 of another joined body 50.

[0057] Advantages of the embodiment will be described. In order to automatically inspect the joint 50 using the manipulator 21, it is necessary to teach in advance the position and orientation of the detector 22 during inspection. Teaching is performed by a teaching playback method. The following is a teaching method according to a reference example. A user of the robot 20 prepares the joint 50. The user visually checks the welded portion 53 of the joint 50. The user moves the manipulator 21 by hand or with the operation terminal 11, and brings the tip of the detector 22 into contact with the center of the welded portion 53. The control device 10 sets the position and orientation of the tip of the detector 22 at that time as a teaching point.

[0058] In order to bring the tip of the detector 22 into contact with the center of the welded portion 53, the position of the detector 22 needs to be finely adjusted. If the user is not familiar with this task, it takes a long time to set the teaching point. The taught position also varies. During teaching, the detector 22 may come into contact with the joint 50, which may damage the detector 22. In addition, a weld mark exists at the position where the welded portion 53 is formed. The user takes the center of the weld mark as the center of the welded portion 53 and brings the detector 22 into contact with the center of the weld mark. However, the center of the weld mark may deviate from the center of the actual welded portion 53. If the position of the detector 22 deviates from the center of the welded portion 53, the accuracy of the inspection may decrease. For this reason, a technology that can more easily set the center of the welded portion 53 as a teaching point is desired.

[0059] Regarding this problem, in the processing system 1 according to the embodiment, a position teaching process is executed. In the position teaching process, it is automatically determined whether the position of the detector 22 is deviated from the center position of the welded portion 53 based on the strength data obtained by the exploration. If the position of the detector 22 is deviated from the center position of the welded portion 53, the processing system 1 controls the manipulator 21 so that the detector 22 approaches the center position of the welded portion 53. Therefore, the user does not need to adjust the position of the detector 22. The variation in the taught position can also be suppressed. Damage to the detector 22 during teaching can be suppressed. In addition, the position of the detector 22 can be aligned with the center position of the welded portion 53, which cannot be visually confirmed by the user. According to the embodiment, the center position of the welded portion 53 can be set as a teaching point more easily.

[0060] (First Modification) FIG. 8 is a flowchart showing a teaching method according to a first modified example of the embodiment. The posture of the detector 22 affects the intensity data obtained by the inspection. The posture of the detector 22 is preferably perpendicular to the surface of the welded portion 53. As shown in Fig. 8, the processing system 1 may execute a posture teaching process (step S20) in addition to the position teaching process (step S10).

[0061] In the posture teaching process, the processing device 12 causes the detector 22 to perform an exploration while the detector 22 is in contact with the welded portion (step S21). The detector 22 acquires intensity data (second intensity data) indicating the intensity of the reflected wave by the exploration (step S22). The processing device 12 calculates, based on the intensity data, how much the posture (first posture) of the detector 22 at the time of the exploration is inclined with respect to the welded portion 53 (step S23). The processing device 12 transmits the calculated inclination to the control device 10. The control device 10 compares the inclination with a preset threshold value (second threshold value) (step S24).

[0062] If the inclination is equal to or smaller than the threshold, the control device 10 sets the attitude of the teaching point based on the first attitude (step S25). For example, the control device 10 sets the first attitude as the attitude of the teaching point. The control device 10 may set the attitude obtained by calculation for the first attitude as the attitude of the teaching point.

[0063] If the tilt exceeds the threshold, the control device 10 rotates the detector 22 around the X direction or the Y direction so as to reduce the tilt (step S26). For example, the tip of the detector 22 is set as the center of rotation. The control device 10 refers to the attitude (second attitude) of the detector 22 after the rotation. The control device 10 sets the attitude of the teaching point based on the second attitude (step S27). For example, the control device 10 sets the second attitude as the attitude of the teaching point. The control device 10 may set the attitude obtained by calculation for the second attitude as the attitude of the teaching point.

[0064] After step S26, the control device 10 may execute step S24 again. In this case, the slope is compared with the threshold again. Step S is repeated until the slope is equal to or smaller than the threshold. 26 is This is repeated. This makes it possible to set the orientation of the teaching point more appropriately. The control device 10 stores the teaching point that has been set (step S28).

[0065] FIG. 9 is a schematic diagram showing a detector. The posture corresponds to the direction D1 of the detector 22 shown in Fig. 9, for example. The direction D1 is perpendicular to the arrangement direction of the multiple detection elements 22a. The inclination is represented by the angle θx about the X direction and the angle θy about the Y direction between the direction D1 of the detector 22 and the normal direction D2 of the welded portion 53.

[0066] The angle representing the posture shown in Fig. 8 may be different from the angle in the robot coordinate system used to express the teaching point. The control device 10 or the processing device 12 may convert the inclination calculated in step S23 into the robot coordinate system as appropriate. When setting the teaching point, the control device 10 or the processing device 12 may convert the angle representing the posture of the detector 22 into an angle in the robot coordinate system as appropriate.

[0067] 10(a) to 10(c) are examples of images obtained during the inspection. A method for calculating the slope will now be described. Fig. 10(a) is an image showing the intensity distribution of the reflected wave in the XY plane near the welded portion 53. Fig. 10(b) is an image showing the intensity distribution of the reflected wave in the YZ plane near the welded portion 53. Fig. 10(c) is an image showing the intensity distribution of the reflected wave in the XZ plane near the welded portion 53. In each of the images in Figs. 10(a) to 10(c), the brightness corresponds to the intensity of the reflected wave. That is, the brighter the color of a pixel, the higher the reflected wave intensity at that point.

[0068] The angle θx is calculated based on the detection result in the YZ plane as shown in Fig. 10(b). The angle θy is calculated based on the detection result in the XZ plane as shown in Fig. 10(c). Specifically, the processing device 12 calculates the average of the three-dimensional brightness gradient. The processing device 12 uses the average of the gradient around the X direction as the angle θx. The processing device 12 uses the average of the gradient around the Y direction as the angle θy.

[0069] The attitude teaching process may be performed before or after the position teaching process. The position teaching process and the attitude teaching process may be performed based on the result of one search.

[0070] 11(a) and 11(b) are schematic diagrams showing the intensity distribution of the reflected wave. Preferably, the posture teaching process is performed after the position teaching process. When the center position of the welded portion 53 is shifted from the position of the detector 22 and the detector 22 is inclined with respect to the welded portion 53, as shown in FIG. 11(a), multiple reflected waves from the welded portion 53 may not be detected by the detector 22. Multiple reflected waves are reflected waves detected at a deep position in the Z direction. If multiple reflected waves are not detected, the accuracy of the calculated posture of the detector 22 may decrease. By performing the position teaching process before the posture teaching process, multiple reflected waves from the welded portion 53 are more easily detected as shown in FIG. 11(b). This allows the posture of the detector 22 to be calculated with higher accuracy.

[0071] (Second Modification) Fig. 12 is a flowchart showing a teaching method according to a second modified example of the embodiment. Fig. 13(a) and Fig. 13(b) are schematic diagrams for explaining the teaching method according to the second modified example of the embodiment. 5, the teaching method according to the second modified example includes step S19 instead of step S1. Also, the teaching method according to the second modified example includes steps S15a and S17a instead of steps S15 and S17.

[0072] In step S19, the processing system 1 sets the distance in the Z direction between the detector 22 and the welded portion 53 to a first distance. The first distance is longer than a second distance in the Z direction between the detector 22 and the welded portion 53 when the inspection process is performed. At this time, as shown in FIG. 13(a), the detector 22 is in contact with the bonded body 50 via the couplant liquid 55. The detector 22 is not in direct contact with the bonded body 50.

[0073] Thereafter, the processing system 1 executes steps S11 to S14 in the same manner as the teaching method shown in Fig. 5. In step S15a, the processing system 1 sets a teaching point based on the first position. At this time, the control device 10 sets the distance in the Z direction between the detector 22 and the welded portion 53 to the second distance. This causes the detector 22 to approach the welded portion 53. For example, as shown in Fig. 13(b), the detector 22 comes into direct contact with the bonded body 50. The processing system 1 sets a teaching point based on the first position in the XY plane and the position of the detector 22 in the Z direction after approach.

[0074] Similarly, in step S17a, the processing system 1 sets a teaching point based on the second position. At this time, the control device 10 sets the distance in the Z direction between the detector 22 and the welded portion 53 to the second distance. The processing system 1 sets the teaching point based on the second position in the XY plane and the position of the detector 22 in the Z direction after approach.

[0075] The first distance can be set by moving the detector 22 closer to the bonded body 50 while performing the search. If the detector 22 is far from the bonded body 50 and the couplant liquid 55, the ultrasonic waves are attenuated and the reflected waves are not detected. When the detector 22 comes into contact with the couplant liquid 55, the ultrasonic waves propagate through the couplant liquid 55 and the reflected waves are detected. The control device 10 gradually moves the detector 22 closer to the bonded body 50 and stops the detector 22 when the reflected waves are detected. This sets the distance between the detector 22 and the bonded body 50 to the first distance.

[0076] Alternatively, the first distance may be set by bringing the detector 22 into contact with the bonded structure 50 and then moving the detector 22 slightly away from the bonded structure 50. The control device 10 moves the detector 22 closer to the bonded structure 50 until the sensor 22d detects the detector 22's contact with the bonded structure 50. After the contact is detected, the control device 10 moves the detector 22 slightly away from the bonded structure 50. The distance by which the detector 22 is moved away is set in advance. Thus, the distance between the detector 22 and the bonded structure 50 is set to the first distance.

[0077] After the contact is detected, the detector 22 may be gradually moved away from the bonded structure 50 while the search is being performed. The control device 10 gradually moves the detector 22 away from the bonded structure 50 while the reflected wave is being detected. When the reflected wave is no longer detected, the control device 10 moves the detector 22 to the position in the Z direction where the reflected wave was last detected. This sets the distance between the detector 22 and the bonded structure 50 to the first distance.

[0078] When step S16 is performed, the distance in the Z direction between the detector 22 and the welded portion 53 is set to a first distance. That is, when step S16 is performed, the control device 10 moves the detector 22 along the XY plane without moving the detector 22 away from the welded portion 53. At this time, the detector 22 is in contact with the bonded body 50 via the couplant liquid. Therefore, when the detector 22 moves, friction between the detector 22 and the bonded body 50 can be reduced. In addition, since the operation of moving the detector 22 away from the welded portion 53 is not required, the time required to perform the teaching method can be shortened.

[0079] In the teaching method according to the second modification, a posture teaching process may be further executed, similarly to the first modification. As described above, the posture teaching process is preferably executed after the position teaching process.

[0080] FIG. 14 is a flowchart showing the inspection process according to the embodiment. When the teaching point is set by any of the teaching methods described above, the robot system 2 executes an inspection process (step S30). The control device 10 causes the dispenser 25 to discharge the couplant liquid 55 to the bonded body 50 (step S31). The control device 10 operates the manipulator 21 to set the position and orientation of the detector 22 to the position and orientation of the teaching point (step S32). The control device 10 causes the detector 22 to perform an inspection of the welded portion 53 (step S33). The processing device 12 identifies the welded portion 53 based on the obtained strength data (third strength data) (step S34). The processing device 12 inspects the welded portion 53 (step S35). In the inspection, for example, the diameter of the welded portion 53 is compared with a threshold value. The processing device 12 stores the inspection result (step S36).

[0081] According to the processing method including the teaching method and the inspection processing, the center position of the welded portion 53 can be set as a teaching point more easily, and the welded portion 53 can be inspected using the set teaching point.

[0082] FIG. 15 is a schematic diagram showing the structure of another detector. In the above, an example has been described in which the couplant liquid 55 is used when performing the exploration. If the detector is provided with a propagation member that can deform according to the shape of the welded portion 53, the couplant liquid 55 can be omitted.

[0083] The detector 23 shown in Fig. 15 includes a first propagation member 22b1 and a second propagation member 22b2. The first propagation member 22b1 is attached to a housing 22c of the detector 23. The first propagation member 22b1 is capable of propagating ultrasonic waves. For example, the first propagation member 22b1 is in contact with the multiple detection elements 22a. Alternatively, another member capable of propagating ultrasonic waves may be provided between the first propagation member 22b1 and the multiple detection elements 22a.

[0084] The second propagation member 22b2 is attached to the first propagation member 22b1. The second propagation member 22b2 may be adhered to the first propagation member 22b1 or may be fixed to the first propagation member 22b1 by a fixture (not shown). The first propagation member 22b1 is located between the multiple detection elements 22a and the second propagation member 22b2. The second propagation member 22b2 is capable of propagating ultrasonic waves. The ultrasonic waves propagating through the first propagation member 22b1 propagate through the second propagation member 22b2 and are transmitted to the outside of the detector 23.

[0085] The first propagation member 22b1 is solid. The first propagation member 22b1 has sufficient hardness so that substantial deformation does not occur even when the detector 22 is in operation. The second propagation member 22b2 is gel-like, not liquid. The second propagation member 22b2 is softer than the first propagation member 22b1. That is, the hardness of the second propagation member 22b2 is smaller than the hardness of the first propagation member 22b1. Therefore, the second propagation member 22b2 is more easily deformed than the first propagation member 22b1. The first propagation member 22b1 has sufficient softness so that it can deform according to the surface shape of the inspection target during inspection.

[0086] The first propagation member 22b1 and the second propagation member 22b2 include resin. As a specific example, the first propagation member 22b1 includes acrylic. The second propagation member 22b2 includes segmented polyurethane. The acoustic impedance of a typical steel plate used for joining is 4.5×10 7 (Pa·s / m). In order to allow sufficient propagation of ultrasonic waves between the detector 22 and the bonded body 50, the acoustic impedance of each of the first propagation member 22b1 and the second propagation member 22b2 is about 1.0×10 5 (Pa s / m) greater than 1.0×10 8 It is preferable that the acoustic impedance is smaller than (Pa·s / m). The acoustic impedance can be measured in accordance with JIS A1405-1 (ISO 10534-1).

[0087] The processing system 1 may execute the above-mentioned teaching method for the robot 20 including the detector 23 instead of the detector 22. However, in step S16 in any teaching method, when the detector 23 is moved along the XY plane, it is preferable that the control device 10 moves the detector 23 away from the joined body 50. Since the second transmission member 22b2 is gel-like, friction between the second transmission member 22b2 and the joined body 50 is large. If the detector 22 is moved in a state where the second transmission member 22b2 is in contact with the joined body 50, the second transmission member 22b2 may be damaged. By moving the detector 23 along the XY plane after moving the detector 23 away from the joined body 50, damage to the second transmission member 22b2 can be suppressed.

[0088] FIG. 16 is a schematic diagram showing a hardware configuration. The control device 10, the operation terminal 11, and the processing device 12 each include, for example, the configuration of a computer 90 shown in Fig. 16. The computer 90 includes a CPU 91, a ROM 92, a RAM 93, a storage device 94, an input interface 95, an output interface 96, and a communication interface 97.

[0089] The ROM 92 stores a program for controlling the operation of the computer 90. The ROM 92 stores a program necessary for causing the computer 90 to realize each of the above-mentioned processes. The RAM 93 functions as a storage area in which the programs stored in the ROM 92 are expanded.

[0090] The CPU 91 includes a processing circuit. The CPU 91 uses a RAM 93 as a working memory and executes a program stored in at least one of a ROM 92 and a storage device 94. During execution of the program, the CPU 91 controls each component via a system bus 98 and executes various processes.

[0091] The storage device 94 stores data necessary for executing the programs and data obtained by executing the programs.

[0092] The input interface (I / F) 95 connects the computer 90 and the input device 95a. The input I / F 95 is, for example, a serial bus interface such as USB. The CPU 91 can read various data from the input device 95a via the input I / F 95.

[0093] The output interface (I / F) 96 connects the computer 90 and the output device 96a. The output I / F 96 is, for example, a video output interface such as a Digital Visual Interface (DVI) or a High-Definition Multimedia Interface (HDMI (registered trademark)). The CPU 91 transmits data to the output device 96a via the output I / F 96 and can cause the output device 96a to display an image.

[0094] The communication interface (I / F) 97 connects the computer 90 to a server 97a external to the computer 90. The communication I / F 97 is, for example, a network card such as a LAN card. The CPU 91 can read various data from the server 97a via the communication I / F 97.

[0095] The storage device 94 includes one or more selected from a hard disk drive (HDD) and a solid state drive (SSD). The input device 95a includes one or more selected from a mouse, a keyboard, a microphone (audio input), and a touch pad. The output device 96a includes one or more selected from a monitor and a projector. A device having the functions of both the input device 95a and the output device 96a, such as a touch panel, may be used.

[0096] The functions of the control device 10 and the processing device 12 may be realized by cooperation of three or more computers. The functions of the control device 10 and the processing device 12 may be realized by one computer. The subject of the various processes described above can be appropriately changed between the control device 10 and the processing device 12.

[0097] The various data processing operations described above may be recorded as a program that can be executed by a computer on a magnetic disk (such as a flexible disk or a hard disk), an optical disk (such as a CD-ROM, CD-R, CD-RW, DVD-ROM, DVD±R, DVD±RW), a semiconductor memory, or other non-transitory computer-readable storage medium.

[0098] For example, information recorded on a recording medium can be read by a computer (or an embedded system). The recording medium may have any recording format (storage format). For example, the computer reads a program from the recording medium and causes a CPU to execute instructions described in the program based on the program. The computer may acquire (or read) the program via a network.

[0099] According to the processing system, the robot system, the control device, the teaching method, or the processing method described above, the center position of the welded portion can be set as the teaching point more easily. By using a program that causes a computer to execute the teaching method or the processing method, the center position of the welded portion can be set as the teaching point more easily.

[0100] Although some embodiments of the present invention have been illustrated above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, modifications, etc. can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims. In addition, the above-mentioned embodiments can be implemented in combination with each other. [Explanation of symbols]

[0101] 1: processing system, 2: robot system, 10: control device, 11: operation terminal, 12: processing device, 20: robot, 21: manipulator, 22: detector, 22a: detection element, 22b: propagation part, 22b1: first propagation member, 22b2: second propagation member, 22c: housing, 22d: sensor, 23: detector, 25: discharger, 50: joint, 51: metal plate, 51a: upper surface, 51b: lower surface, 52: metal plate, 53: welded part, 53a: upper surface, 53b: lower surface, 54: solidified part, 55: couplant liquid, 90: computer, 91: CPU, 92: ROM, 93: RAM, 94: storage device, 95: input interface, 95a: input device, 96: output interface, 96a: output device, 97: communication interface, 97a: server, 98: system bus, Pe10 to Pe14: peak, RW: reflected wave, US: ultrasonic wave

Claims

1. A processing system for teaching an operation to a robot including: a detector including a plurality of detection elements arranged along a first direction and a second direction intersecting the first direction; and a manipulator to which the detector is attached, The detector is caused to carry out an inspection of the welded portion of the joint by transmitting ultrasonic waves and detecting reflected waves; calculating a center position of the weld on a first surface along the first direction and the second direction based on first intensity data indicating an intensity of the reflected wave obtained by the exploration; when a distance between the center position and a first position of the detector on the first plane is equal to or less than a first threshold, a teaching point of the robot is set based on the first position; if the distance exceeds the first threshold, moving the detector along the first surface to a second position to decrease the distance, and setting the taught point based on the second position. A processing system that executes a position teaching process.

2. causing the detector to perform the probing on the weld; calculating an inclination of the detector in a first position with respect to the welded portion based on second intensity data indicating an intensity of the reflected wave obtained by the exploration; When the inclination is equal to or smaller than a second threshold value, the teaching point is set based on the first attitude; If the tilt exceeds the second threshold, moving the detector to a second orientation so as to reduce the tilt, and setting the teaching point based on the second orientation. The processing system according to claim 1 , further comprising a posture teaching process.

3. The processing system according to claim 2 , wherein the attitude teaching process is executed after the position teaching process.

4. A processing system as described in any one of claims 1 to 3, wherein, in the position teaching process, if the distance exceeds the first threshold, the detector is moved away from the weld along a third direction perpendicular to the first surface, and then the detector is moved to the second position.

5. In the position teaching process, The reflected wave is detected by the detector in a state where the detector is in contact with the bonded body via a liquid; When setting the teaching point, the detector is brought close to the welding portion along a third direction perpendicular to the first surface, and the teaching point is set based on either the first position or the second position and a position in the third direction after the detector has approached the welding portion. The processing system according to any one of claims 1 to 3.

6. Setting the position of the detector to the position of the teaching point; causing the detector to perform the probe on a weld of another joint; inspecting the welded portion based on third intensity data indicating the intensity of the reflected wave obtained by the exploration; 6. The processing system according to claim 1, wherein an inspection process is executed after the position teaching process.

7. 7. The processing system according to claim 1, wherein a center position of intensity in the first intensity data is calculated as the central position.

8. A processing system according to any one of claims 1 to 7; The robot; A robot system having

9. A control device that causes a robot including a detector and a manipulator to which the detector is attached to perform an exploration of a welded portion of a joint by transmitting ultrasonic waves and detecting reflected waves, and teaches the robot an operation based on a result of the exploration, when a distance between a center position of the weld calculated from the result of the exploration and a first position of the detector is equal to or less than a first threshold value on a first surface along a two-dimensional arrangement direction of a plurality of detection elements included in the detector, a teaching point related to a position when the robot performs the exploration is set based on the first position; A controller that moves the detector along the first surface to a second position to decrease the distance if the distance exceeds the first threshold, and sets the taught point based on the second position.

10. A teaching method for teaching an operation to a robot including: a detector including a plurality of detection elements arranged along a first direction and a second direction intersecting the first direction; and a manipulator to which the detector is attached, the method comprising: The detector is caused to carry out an inspection of the welded portion of the joint by transmitting ultrasonic waves and detecting reflected waves; calculating a center position of the weld on a first surface along the first direction and the second direction based on first intensity data indicating an intensity of the reflected wave obtained by the exploration; when a distance between the center position and a first position of the detector on the first plane is equal to or less than a first threshold, a teaching point of the robot is set based on the first position; if the distance exceeds the first threshold, moving the detector along the first surface to a second position to decrease the distance, and setting the taught point based on the second position. A teaching method including position teaching.

11. causing the detector to perform the probing on the weld; calculating an inclination of the detector in a first position with respect to the welded portion based on second intensity data indicating an intensity of the reflected wave obtained by the exploration; When the inclination is equal to or smaller than a second threshold value, the teaching point is set based on the first attitude; If the tilt exceeds the second threshold, moving the detector to a second orientation so as to reduce the tilt, and setting the teaching point based on the second orientation. The teaching method according to claim 10 , further comprising the step of: teaching a posture.

12. The teaching method according to claim 11 , further comprising the step of: teaching the posture after teaching the position.

13. In the position teaching, The reflected wave is detected by the detector in a state where the detector is in contact with the welded portion via a liquid; When setting the teaching point, the detector is brought close to the welding portion along a third direction perpendicular to the first surface, and the teaching point is set based on either the first position or the second position and a position in the third direction after the detector has approached the welding portion. The teaching method according to any one of claims 10 to 12.

14. The teaching method according to any one of claims 10 to 13, wherein a center position of the intensity in the first intensity data is calculated as the central position.

15. A teaching method for teaching an operation to the robot based on a result of the exploration, the method comprising: causing a robot including a detector and a manipulator to which the detector is attached to perform an exploration of a welded portion of a joint by transmitting ultrasonic waves and detecting reflected waves; when a distance between a center position of the weld calculated from the result of the exploration and a first position of the detector is equal to or less than a first threshold value on a first surface along a two-dimensional arrangement direction of a plurality of detection elements included in the detector, a teaching point related to a position when the robot performs the exploration is set based on the first position; If the distance exceeds the first threshold, moving the detector along the first surface to a second position to decrease the distance, and setting the teaching point based on the second position.

16. A program for causing a computer to execute the teaching method according to any one of claims 10 to 15.

17. A storage medium storing a program for causing a computer to execute the teaching method according to any one of claims 10 to 15.

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