JP2010149225A - Robot system, device and method for controlling robot system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a robot system, and a device and method for controlling the robot system, which accurately and efficiently performs teaching. <P>SOLUTION: In the robot system, a visual sensor moves together with a control point of a robot, and obtains image information of a workpiece that is an objective to work for the robot. A memory part stores position relation data R indicating position relation between the control point of the robot and a specific position within a visual field of the visual sensor. A control part detects a current position P of the control point of the robot. The control part computes a target position PP of the control point of the robot to position a characteristic point at the specific position within the visual field of the visual sensor based on the position relation data R considering a detected current position P of the control point as a position of the characteristic point of the workpiece. Besides, the control part controls the robot to move the robot control point to the target position PP. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a robot system, a control apparatus for the robot system, and a control method.

  In the robot system, the position of the workpiece is taught to the robot in advance, and the robot performs work with the taught position as the position of the workpiece. In recent years, a robot system has been used in which a robot can perform a desired operation even if the work position is deviated from the teaching position by detecting the position of the work with a visual sensor and obtaining a deviation amount from the teaching position. In such a conventional robot system, image information of a workpiece is acquired by a visual sensor. Then, the image processing apparatus analyzes the acquired image information and detects the position of the workpiece. The robot controller corrects the target position of the operation of the robot by obtaining the amount of deviation between the position of the work taught in advance and the position of the work detected by the image processing apparatus during production.

  In the conventional robot system as described above, it is necessary to move the feature point of the workpiece to a specific position (for example, the center position) in the visual field of the visual sensor during teaching work. In this case, the operator needs to operate the teaching device while checking the workpiece image acquired by the visual sensor on the monitor of the image processing device. However, since the monitor and the teaching device cannot be carried together, it is difficult to perform the teaching work while looking at both.

Therefore, in the robot system described in Patent Document 1, an image acquired by the visual sensor can be displayed on the display of the teaching device. In this robot system, the operator can confirm the image acquired by the visual sensor by the image displayed on the display of the teaching device.
JP-A-9-183088

  However, in the robot system described in Patent Document 1 as described above, in teaching work, the operator needs to operate the teaching device so that the workpiece is positioned at a specific position within the visual field of the visual sensor. In this case, in order to correct the positional deviation of the workpiece during production with high accuracy, it is necessary to accurately align the workpiece with a specific position. For this reason, the robot is moved at a low speed, and it takes time to move the workpiece to a specific position.

  Further, when the work is not located within the visual field of the visual sensor at the start of the teaching work, the operator operates the teaching device so that the work is within the visual field. However, when the work is not within the visual field of the visual sensor, the operator cannot confirm the position of the work with a monitor or a display. For this reason, the operator has to operate the teaching device by trial and error until the workpiece enters the field of view.

  As described above, the robot system described in Patent Document 1 still takes time for teaching work and is inefficient.

  An object of the present invention is to provide a robot system, a robot system control device, and a control method capable of performing teaching work with high accuracy and efficiency.

  A robot system according to a first invention includes a robot, a teaching device, a visual sensor, a storage unit, and a control unit. The teaching device is a device operated by an operator to instruct the operation of the robot. The visual sensor moves together with the control point of the robot and acquires image information of a work that is a work target of the robot. The storage unit stores positional relationship data indicating a positional relationship between a control point of the robot and a specific position in the visual field of the visual sensor. The control unit detects the current position of the control point of the robot. The control unit regards the current position of the detected control point as the position of the feature point of the workpiece, and controls the robot such that the feature point is located at a specific position in the visual field of the visual sensor based on the positional relationship data. Calculate the target position of the point. Then, the control unit controls the robot so that the control point of the robot moves to the target position.

  A control device for a robot system according to a second aspect of the present invention provides a robot, a teaching device operated by an operator for instructing the operation of the robot, and image information of a work that is moved along with the control point of the robot and is a work target of the robot. A robot system control device comprising: a visual sensor to acquire. The control device includes a storage unit and a control unit. The storage unit stores positional relationship data indicating a positional relationship between a control point of the robot and a specific position in the visual field of the visual sensor. The control unit detects the current position of the control point of the robot. The control unit regards the current position of the detected control point as the position of the feature point of the workpiece, and controls the robot such that the feature point is located at a specific position in the visual field of the visual sensor based on the positional relationship data. Calculate the target position of the point. Then, the control unit controls the robot so that the control point of the robot moves to the target position.

  According to a third aspect of the present invention, there is provided a robot system control method comprising: a robot; a teaching device operated by an operator to instruct the operation of the robot; and image information of a work that is moved along with the control point of the robot and is a work target of the robot And a storage unit storing positional relationship data indicating a positional relationship between a control point of the robot and a specific position within the visual field of the visual sensor. This control method includes a step of detecting the current position of the control point of the robot, and the feature point is detected by the visual sensor on the basis of the positional relationship data by regarding the detected current position of the control point as the position of the feature point of the workpiece. And calculating a target position of the control point of the robot such that the robot is positioned at a specific position in the field of view, and controlling the robot such that the control point of the robot moves to the target position.

  In the robot system, the robot system control device and the control method described above, the operator first operates the teaching device to move the robot control point to the workpiece feature point. Then, the current position of the control point of the robot is detected in a state where the control point of the robot is located at the feature point of the workpiece. That is, the position of the feature point of the workpiece is detected by detecting the current position of the control point of the robot. Here, since the visual sensor is fixed to the robot, the positional relationship between the control point of the robot and the visual sensor is constant regardless of the posture of the robot. Therefore, based on the current position of the detected control point and the positional relationship data stored in the storage unit, the target position of the robot control point where the feature point is located at a specific position within the visual sensor field of view Can be calculated. Then, when the robot is controlled so that the control point of the robot moves to the calculated target position, the feature point of the workpiece moves to a specific position within the visual field of the visual sensor.

  As described above, in the teaching work, the operator may operate the teaching device and move the control point of the robot to the feature point of the workpiece. Here, since the control point of the robot is set at the tip of the welding torch in, for example, a welding robot, the operator can visually recognize it. Also, the feature points of the workpiece can be visually recognized. Therefore, it is easy for the operator to operate the teaching device and move the control point of the robot to the feature point of the workpiece. Therefore, in this robot system, the robot system control device and the control method, the teaching work can be performed with high accuracy and efficiency.

  A robot system according to a fourth invention includes a robot, a visual sensor, an image analysis device, a storage unit, and a control unit. The visual sensor moves together with the control point of the robot and acquires image information of a work that is a work target of the robot. The image analysis device analyzes the image information acquired by the visual sensor and detects the position of the feature point of the work within the visual field of the visual sensor. The storage unit stores positional relationship data indicating a positional relationship between a control point of the robot and a specific position in the visual field of the visual sensor. The control unit detects the current position of the control point of the robot. Based on the positional relationship data, the position of the feature point of the workpiece detected by the image analysis device, and the detected current position of the control point of the robot, the control unit detects the feature point within the visual sensor field of view. The target position of the control point of the robot that is located at a specific position is calculated. Then, the control unit controls the robot so that the control point of the robot moves to the target position.

According to a fifth aspect of the present invention, there is provided a robot system control device, comprising: a robot; a visual sensor that moves together with a robot control point and acquires image information of a workpiece that is a work target of the robot; An image analysis device that detects a position of a feature point of a work within a visual field of a visual sensor. The control device includes a storage unit and a control unit. The storage unit stores positional relationship data indicating a positional relationship between a control point of the robot and a specific position in the visual field of the visual sensor. The control unit detects the current position of the control point of the robot. Based on the positional relationship data, the position of the feature point of the workpiece detected by the image analysis device, and the detected current position of the control point of the robot, the control unit detects the feature point within the visual sensor field of view. The target position of the control point of the robot that is located at a specific position is calculated. Then, the control unit controls the robot so that the control point of the robot moves to the target position. The control method of the robot system according to the sixth aspect of the invention moves with the robot and the control point of the robot and is a work target of the robot. A visual sensor for acquiring image information of the workpiece, an image analysis device for analyzing the image information acquired by the visual sensor to detect the position of the feature point of the workpiece in the visual field of the visual sensor, a control point of the robot, and a visual sensor And a storage unit that stores positional relationship data indicating a positional relationship with a specific position in the field of view. In this control method, a step of acquiring image information of a workpiece by a visual sensor and an image analysis device analyzing the image information acquired by the visual sensor to detect a position of a feature point of the workpiece in the visual field of the visual sensor. A step, a step of detecting a current position of a control point of the robot, the positional relationship data, a position of a feature point of the workpiece detected by the image analyzer, and a control point of the robot detected by the current position detector And calculating the target position of the robot control point such that the feature point is located at a specific position within the visual sensor field of view, and the robot so that the robot control point moves to the target position. Controlling.

  In the robot system, the robot system control apparatus, and the control method described above, first, image information of a workpiece is acquired by a visual sensor. Next, the position of the feature point of the workpiece is detected by analyzing the acquired image information. Also, the current position of the robot control point is detected. Here, since the visual sensor moves together with the control point of the robot, the positions of the control point of the robot and the visual sensor are relatively fixed. Therefore, based on the positional relationship data stored in the storage unit, the position of the feature point of the workpiece, and the current position of the control point of the robot, the feature point of the workpiece is positioned at a specific position in the visual field of the visual sensor. The target position of the robot control point can be calculated. Then, when the robot is controlled so that the control point of the robot moves to the calculated target position, the feature point of the workpiece moves to a specific position within the visual field of the visual sensor.

  As described above, the robot is automatically controlled so that the feature point of the workpiece is located at a specific position within the visual field of the visual sensor. Therefore, in this robot system, the robot system control device and the control method, the teaching work can be performed with high accuracy and efficiency.

  With the robot system, the robot system control apparatus, and the control method according to the present invention, teaching work can be performed with high accuracy and efficiency.

<First Embodiment>
〔Constitution〕
The configuration of the robot system according to the first embodiment of the present invention is shown in FIG. 1 and FIG. This robot system includes a robot 1, a visual sensor 2, an image processing device 3, a robot controller 4, and a teaching device 5.

  The robot 1 is a welding robot, and as shown in FIG. 3, an articulated robot arm 14 composed of a plurality of arm members 11 to 13 rotatably connected to each other, and a plurality of motors 61 that drive the robot arm 14. ˜66 (see FIG. 2) and a welding torch 15 provided at the tip of the robot arm 14. The robot arm 14 is fixed to the pedestal 16. The robot 1 moves the welding torch 15 by driving the robot arm 14 with a plurality of motors 61 to 66. As a result, the robot 1 welds the workpiece W. Further, as shown in FIG. 2, encoders 71 to 76 are attached to the plurality of motors 61 to 66, respectively. The encoders 71 to 76 detect the rotation angles of the motors 61 to 66 and send them to the robot controller 4.

  The visual sensor 2 acquires image information of the workpiece W. As shown in FIG. 4, the visual sensor 2 is fixed to the tip of the robot arm 14 together with the welding torch 15 and moves together with the welding torch 15. As illustrated in FIG. 5A, the visual sensor 2 includes a slit light source (not shown) such as a semiconductor laser, a camera 21 such as a CCD camera or a CMOS camera, and a filter 22. The slit light source irradiates the workpiece WW with laser light obliquely. The filter 22 transmits only light having the same wavelength as the laser light. The camera 21 detects the laser light reflected from the workpiece W. The visual sensor 2 detects, for example, an image as shown in FIG. 5B with respect to the workpiece W shown in FIG. In the image acquired by the visual sensor 2, a change point on the surface of the workpiece W appears as a feature point P0 on the image. Further, when the actual position of the workpiece W is shifted vertically and horizontally, the position of the workpiece W is also shifted vertically and horizontally on the image detected by the visual sensor 2.

  The image processing device 3 detects the feature point of the workpiece W by analyzing the image information acquired by the visual sensor 2. The image processing apparatus 3 is provided with a monitor, and the acquired image information is displayed on the monitor. As illustrated in FIG. 2, the image processing apparatus 3 includes an image processing unit 31 and a storage unit 32.

  For example, when the original image as shown in FIG. 6A is acquired by the visual sensor 2, the image processing unit 31 performs image processing on the original image and calculates the characteristic points as shown in FIG. 6B. Find P0. In this example, a break point is obtained as the feature point P0.

  The storage unit 32 stores positional relationship data. The positional relationship data is data indicating the positional relationship between the control point of the robot 1 and the central position in the visual field of the visual sensor 2. The positional relationship data is used in alignment control described later.

  The robot controller 4 has a control unit 41. The control unit 41 controls the robot 1 in accordance with a preset production program. For example, a location to be welded to the workpiece W is set in the production program, and the control unit is configured to weld the location set in the production program based on the position of the feature point of the workpiece W taught in advance. To control the robot. The robot controller 4 defines the tip of the welding torch 15 as a control point Pc (see FIG. 4), and controls the position of the control point Pc viewed from the robot coordinates Xr-Yr-Zr shown in FIG. The operation of the robot 1 is controlled. Here, the robot coordinates Xr-Yr-Zr is a coordinate system fixed to the base 16 of the robot 1. Further, the robot controller 4 defines tool coordinates Xt-Yt-Zt shown in FIG. 4 and sensor coordinates Xs-Ys shown in FIG. The tool coordinates Xt-Yt-Zt is a coordinate system fixed to the welding torch 15 with the control point Pc as the origin. The sensor coordinates Xs-Ys is a coordinate system fixed to the visual field Vw of the visual sensor 2. In FIG. 4, the visual field Vw of the visual sensor 2 that cannot be seen by the operator is virtually indicated by a two-dot chain line. Here, the visual field Vw of the visual sensor 2 indicates an area projected on the Xr-Yr plane at a predetermined Zr coordinate when the arm member 11 that is the wrist axis of the robot 1 takes a vertically downward posture.

  Further, the control unit 41 corrects the operation of the robot 1 based on the position of the workpiece W detected by the image processing device 3 during production. For example, the control unit 41 receives the position (Xm, Xm) of the feature point P0 of the workpiece W at the time of teaching shown in FIG. 7A and the workpiece W at the time of production shown in FIG. The position (Xp, Yp) of the feature point P0 is acquired. The control unit calculates a difference (ΔX, ΔY) between the teaching position (Xm, Xm) and the production position (Xp, Yp). Since (ΔX, ΔY) is sensor coordinates, it is converted into a position difference (ΔXR, ΔYR) in robot coordinates. Then, the controller 41 shifts the movement position of the robot 1 (ΔXR, ΔYR) from the position set by the production program during production. Thereby, the robot 1 can perform welding at a correct position even if the workpiece W is deviated from the teaching position.

  The teaching device 5 has a monitor and operation buttons, and the robot 1 can be operated by an operator. Specifically, in the teaching work, the operator can arbitrarily move the control point Pc of the robot 1 by operating the teaching device 5. The teaching device 5 is provided with a setting button for instructing execution of alignment control described later. The teaching device 5 is connected to the robot controller 4, and the operation content by the teaching device 5 is transmitted to the robot controller 4. The operator can also set a production program using the teaching device 5.

(Positioning control)
Hereinafter, the characteristic alignment control in the present invention will be described based on the flowchart shown in FIG.

  First, in step S1, the operator sets the workpiece W at a predetermined work position for teaching, and operates the teaching device 5 to adjust the control point Pc to the feature point P0 of the workpiece W. That is, as shown in FIG. 9, the operator moves the welding torch 15 so that the tip of the welding torch 15 matches the feature point P0 of the workpiece W.

  In step S <b> 2, the operator presses a setting button provided on the teaching device 5.

  Then, in step S3, the positional relationship data R stored in advance in the storage unit 32 is read (see the following formula 1). Here, the positional relationship data R is a vector representing the relationship between the center position of the visual field Vw in the tool coordinates and the tool coordinate origin, that is, the control point Pc. Since the welding torch 15 and the visual sensor 2 are provided so that their positional relationship is fixed, the positional relationship data R can be obtained at the time of designing or manufacturing the robot system.

  In step S4, the control unit 41 calculates a tool coordinate / robot coordinate conversion matrix MT from the current angles of the motors 61 to 66 of the robot 1 (see the following formula 2).

The element mtij (ij = 1 to 3) is a function of the current angle Θ of each of the motors 61 to 66, and θ1 to θ6 are the angles of the motors 61 to 66 detected by the encoders 71 to 76 described above. .

  In step S5, the control unit 41 calculates a vector RR from the center position of the visual field Vw of the visual sensor 2 in the robot coordinates to the feature point P0 of the workpiece W based on the matrix MT and the positional relationship data R (hereinafter described as follows). (See Equation 3). That is, the positional relationship data R, which is a vector indicating the positional relationship between the control point Pc in the tool coordinates and the center position of the visual field Vw, is converted into robot coordinates.

  In step S6, the control unit 41 detects the current position P of the control point Pc. Here, the control unit 41 calculates the current position P of the control point Pc from the current angle Θ of each of the motors 61 to 66 detected by the encoders 71 to 76. That is, the current position P of the control point Pc is expressed as a function of the current angle Θ of each motor 61-66.

  In step S7, the control unit 41 calculates a target position PP of the control point Pc in the robot coordinates based on the current position P of the control point Pc and the vector RR (see the following formula 4).

  In step S8, the control unit 41 sends a command to the robot 1 to move the control point Pc to the target position PP.

  In step S9, it is determined whether or not the control point Pc has reached the target position PP. When the control point Pc reaches the target position PP, the alignment control is finished. At this time, as shown in FIG. 10, the feature point P0 of the work W has moved to the center position of the visual field Vw of the visual sensor 2, and the feature point P0 of the work W is located within the visual field Vw of the visual sensor 2. Yes. Further, as shown in FIG. 7A, an image in which the feature point P0 of the workpiece W is located at the center position of the visual field of the visual sensor 2 is acquired by the visual sensor 2.

〔Characteristic〕
In this robot system, the teaching operation can be easily performed by performing the above-described alignment control at the start of the teaching operation. At this time, the operator may perform an operation of matching the control point Pc of the robot 1 with the feature point P0 of the workpiece W. Then, when the operator presses the setting button, the robot 1 is automatically controlled so that the feature point P0 of the workpiece W moves to the center position of the visual field of the visual sensor 2. Here, since the operator can directly recognize the control point Pc of the robot 1 and the feature point P0 of the workpiece W, the feature point P0 of the workpiece W is located outside the visual field of the visual sensor 2. Even so, the operator can easily perform the above-described operation. Thereby, in this robot system, teaching work can be performed accurately and efficiently.

<Second Embodiment>
Positioning control in the robot system according to the second embodiment of the present invention will be described based on the flowchart of FIG. The configuration of the robot system is the same as that of the first embodiment. In the present embodiment, it is assumed that the feature point P0 of the workpiece W is located in the visual field Vw of the visual sensor 2 in advance.

  First, in step S <b> 11, the operator presses a setting button provided on the teaching device 5.

  Then, in step S12, the positional relationship data M (see the following formula 5) stored in advance in the storage unit 32 is read. The positional relationship data M is a matrix that represents the posture relationship between tool coordinates and sensor coordinates. Since the welding torch 15 and the visual sensor 2 are fixed to each other, the positional relationship data M can be obtained at the time of designing or manufacturing the robot system.

  In step S13, the control unit 41 acquires a position Vs = (Xw, Yw, 0) from the center position of the visual field Vw of the feature point P0 of the workpiece W. Here, the control unit 41 calculates the above Vs from the position (Xw, Yw) of the feature point P0 of the workpiece W at the sensor coordinates detected by the image processing device 3.

  In step S14, the control unit 41 determines the visual field Vw of the visual sensor 2 in the tool coordinates based on the position Vs of the feature point P0 of the workpiece W from the central position of the visual field Vw of the visual sensor 2 and the positional relationship data M. A vector RS from the center position to the feature point P0 of the workpiece W is calculated (see the following number).

  In step S15, the control unit 41 calculates a tool coordinate / robot coordinate conversion matrix MT from the current angles of the motors 61 to 66 of the robot 1 (see the following Expression 7).

The element mtij (ij = 1 to 3) is a function of the current angle Θ of each of the motors 61 to 66, and θ1 to θ6 are the angles of the motors 61 to 66 detected by the encoders 71 to 76 described above. .

  In step S16, the control unit 41 visually determines the robot coordinates based on the vector RS from the center position of the visual field Vw of the visual sensor 2 in the tool coordinates to the feature point P0 of the workpiece W and the tool coordinates / robot coordinate transformation matrix MT. A vector RR from the center position of the field of view Vw of the sensor 2 to the feature point P0 of the workpiece W is calculated (see the following formula 8). That is, the vector from the center position of the visual field Vw of the visual sensor 2 to the feature point P0 of the workpiece W is converted from tool coordinates to robot coordinates.

  In step S17, the control unit 41 detects the current position P of the control point Pc. Here, the control unit 41 calculates the current position P of the control point Pc from the current angle Θ of each of the motors 61 to 66 detected by the encoders 71 to 76. That is, the current position P of the control point Pc is expressed as a function of the current angle Θ of each motor 61-66.

  In step S18, the control unit 41 calculates a target position PP of the control point Pc in the robot coordinates based on the current position P of the control point Pc and the vector RR (see Equation 9 below and FIG. 12).

  In step S19, the control unit 41 sends a command to the robot 1 to move the control point Pc to the target position PP.

  In step S20, it is determined whether or not the control point Pc has reached the target position PP. When the control point Pc reaches the target position PP, the alignment control is finished. At this time, as in the first embodiment, as shown in FIG. 10, the feature point P0 of the workpiece W has moved to the center position of the visual field Vw of the visual sensor, and the workpiece W is the visual field Vw of the visual sensor 2. Located in. Thereby, as shown in FIG. 7A, an image in which the feature point P0 of the workpiece W is located at the center position of the visual field Vw is acquired by the visual sensor 2.

〔Characteristic〕
In this robot system, when the operator presses the setting button in a state where the workpiece W is positioned in the visual field Vw of the visual sensor 2, the feature point P0 of the workpiece W moves to the center position in the visual field Vw of the visual sensor 2. Thus, the robot 1 is automatically controlled. Therefore, in this robot system, teaching work can be performed accurately and efficiently.

<Third Embodiment>
In the alignment control in the robot system according to the third embodiment of the present invention, the alignment control in the first embodiment and the alignment control in the second embodiment are continuously performed. In other words, after step S9 of the flowchart of FIG. 8, the processing after step S12 of the flowchart of FIG. 11 is performed. The configuration of the robot system is the same as that of the first embodiment.

  In the robot system according to the present embodiment, the feature point P0 of the workpiece W is easily moved within the field of view Vw of the visual sensor 2 even when the feature point P0 of the workpiece W is located outside the visual field of the visual sensor 2. Can be made. Moreover, even if the position of the feature point P0 of the workpiece W is shifted from the center position of the visual sensor 2 after the execution of step S9, the position of the feature point P0 of the workpiece W is corrected by the processing after step S12. The visual sensor 2 can be accurately moved to the center position. For this reason, in this robot system, the teaching work can be performed with higher accuracy.

<Other embodiments>
(A) The configuration and control method of the robot system are not limited to those described above, and can be changed without departing from the gist of the present invention. For example, the structure of the robot 1 is not limited to that described above, and another type of robot such as a handling robot that holds and moves the workpiece W may be used. Further, the configuration of the visual sensor 2 and the image processing method by the image processing device 3 are not limited to those described above. For example, a two-dimensional visual sensor and an image processing apparatus that process brightness information may be used, and the present invention is applicable to a visual sensor that projects a plurality of pattern lights to obtain three-dimensional coordinates.

  (B) In the above embodiment, the storage unit 32 is provided in the image processing device 3, but may be provided in another device such as the robot controller 4.

  (C) In the above embodiment, the alignment control is started by pressing the setting button provided on the teaching device 5, but another operation member may be provided instead of the setting button.

  (D) The specific position in the visual field Vw of the visual sensor 2 is not limited to the center position, and may be another position in the visual field Vw.

  (E) The control point Pc of the robot 1 may not be the tip of the welding torch 15 but may be another position where the positional relationship with respect to the visual sensor 2 does not change.

  INDUSTRIAL APPLICABILITY The present invention has an effect that teaching work can be performed accurately and efficiently, and is useful as a robot system, a robot system control device, and a control method.

Schematic which shows the structure of a robot system. The block diagram which shows the structure of a robot system. The figure which shows the structure and robot coordinate of a robot. The figure which shows a welding torch and a visual sensor. The figure which shows an example of a structure of a visual sensor, and the image acquired. The figure which shows an example of the image processing by an image processing apparatus. The figure which shows the example of detection of the feature point of the workpiece | work W by an image processing apparatus. The flowchart which shows the alignment control which concerns on 1st Embodiment. The figure which shows the position of the feature point of the welding torch and the workpiece | work W at the time of the start of alignment control. The figure which shows the feature point of the workpiece | work W at the time of completion of alignment control, and the visual field of a visual sensor. The flowchart which shows the alignment control which concerns on 2nd Embodiment. The figure which shows the relationship between the present position P of the control point Pc in the robot coordinate, the vector RR from the center position of the visual field Vw to the feature point P0 of the workpiece W, and the target position PP of the control point Pc.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Robot 2 Visual sensor 5 Teaching apparatus 32 Memory | storage part 41 Control part

Claims (6)

With robots,
A teaching device operated by an operator to instruct the operation of the robot;
A visual sensor that moves together with the control point of the robot and acquires image information of a work that is a work target of the robot;
A storage unit that stores positional relationship data indicating a positional relationship between a control point of the robot and a specific position in the visual field of the visual sensor;
The current position of the control point of the robot is detected, the current position of the detected control point is regarded as the position of the feature point of the workpiece, and the feature point is within the visual field of the visual sensor based on the positional relationship data. A control unit that calculates a target position of the control point of the robot so as to be located at the specific position, and controls the robot so that the control point of the robot moves to the target position;
A robot system comprising: A robot, a teaching device operated by an operator to instruct the operation of the robot, and a visual sensor that moves together with a control point of the robot and acquires image information of a work that is a work target of the robot A control device for a robot system,
A storage unit that stores positional relationship data indicating a positional relationship between a control point of the robot and a specific position in the visual field of the visual sensor;
The current position of the control point of the robot is detected, the current position of the detected control point is regarded as the position of the feature point of the workpiece, and the feature point is within the visual field of the visual sensor based on the positional relationship data. A control unit that calculates a target position of the control point of the robot so as to be located at the specific position, and controls the robot so that the control point of the robot moves to the target position;
A control device for a robot system comprising: A robot, a teaching device operated by an operator to instruct the operation of the robot, a visual sensor that moves together with a control point of the robot and acquires image information of a work that is a work target of the robot, and the robot A storage unit that stores positional relationship data indicating a positional relationship between the control point of the visual sensor and a specific position within the visual field of the visual sensor,
Detecting a current position of a control point of the robot;
The current position of the control point detected by the position detection unit is regarded as the position of the feature point of the workpiece, and based on the positional relationship data, the feature point is positioned at a specific position in the visual field of the visual sensor. Calculating a target position of the control point of the robot;
Controlling the robot such that a control point of the robot moves to the target position;
A method for controlling a robot system comprising: With robots,
A visual sensor that moves together with the control point of the robot and acquires image information of a work that is a work target of the robot;
An image analyzer for analyzing the image information acquired by the visual sensor and detecting the position of the feature point of the workpiece in the visual field of the visual sensor;
A storage unit that stores positional relationship data indicating a positional relationship between a control point of the robot and a specific position in the visual field of the visual sensor;
Detecting the current position of the control point of the robot, and based on the positional relationship data, the position of the feature point of the workpiece detected by the image analyzer, and the detected current position of the control point of the robot Calculating a target position of the control point of the robot such that the feature point is located at a specific position in the visual field of the visual sensor, and controlling the robot so that the control point of the robot moves to the target position A control unit;
A robot system comprising: A robot, a visual sensor that moves with a control point of the robot, acquires image information of a work that is a work target of the robot, and analyzes the image information acquired by the visual sensor, and the visual sensor in the visual field of the visual sensor A control device of a robot system comprising an image analysis device for detecting a position of a feature point of a workpiece,
A storage unit that stores positional relationship data indicating a positional relationship between a control point of the robot and a specific position in the visual field of the visual sensor;
Detecting the current position of the control point of the robot, and based on the positional relationship data, the position of the feature point of the workpiece detected by the image analyzer, and the detected current position of the control point of the robot Calculating a target position of the control point of the robot such that the feature point is located at a specific position in the visual field of the visual sensor, and controlling the robot so that the control point of the robot moves to the target position A control unit;
A control device for a robot system comprising: A robot, a visual sensor that moves with a control point of the robot, acquires image information of a work that is a work target of the robot, and analyzes the image information acquired by the visual sensor, and the visual sensor in the visual field of the visual sensor An image analysis device that detects the position of a feature point of a workpiece, and a storage unit that stores positional relationship data indicating a positional relationship between a control point of the robot and a specific position in the visual field of the visual sensor. A control method,
Obtaining image information of the workpiece by the visual sensor;
Analyzing the image information acquired by the visual sensor by the image analysis device to detect the position of the feature point of the workpiece in the visual field of the visual sensor;
Detecting a current position of a control point of the robot;
Based on the positional relationship data, the position of the feature point of the workpiece detected by the image analysis device, and the current position of the control point of the robot detected by the current position detection unit, the feature point is Calculating a target position of the control point of the robot such that it is located at a specific position in the visual field of the visual sensor;
Controlling the robot such that a control point of the robot moves to the target position;
A method for controlling a robot system comprising: