JP2008254097A - Relative position calculating method between plurality of robots - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately calculate relative positions between a plurality of robots. <P>SOLUTION: A flange surface 17a of a first robot 1 and a joint surface 7a on one end side of a joining tool 7 are joined with each other, and a flange surface 27a of a second robot 2 and a joint surface 7b on the other end side of the joining tool 7 are joined with each other. While joint parts are moved to measuring points, measuring data indicating the position and posture of each robot 1, 2 is obtained. The measuring data of each robot 1, 2 obtained at three or more measuring points which does not exist on the same straight line is calculated to calculate the relative position between the robots 1, 2. Following changing of the position and the posture of the first robot 1, the position and the posture of the second robot 2 can be changed through the joining tool 7. Therefore, a point instructed by the first robot 1 and a point instructed by the second robot 2 are exactly same as each other. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for calculating a relative position between a plurality of robots working in cooperation.

As a method for calculating the relative position (position and posture) between a plurality of robots working in cooperation, there is a method described in Patent Document 1, for example.
JP 2005-125478 A

  By the way, there is a method in which each robot separately teaches at least three points and calculates the relative position between a plurality of robots. In this method, a point taught by one robot and a point taught by another robot are Since it is difficult to make them identical, it is difficult to accurately calculate the relative position. In addition, it is possible to increase the number of points that each robot teaches separately to provide redundancy, but in this method, the point taught by one robot and the point taught by another robot are made the same. There is a new problem of requiring time and labor.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method capable of accurately calculating a relative position between a plurality of robots.

  According to the first aspect of the present invention, the measurement data representing the position and orientation of each robot in a state where the flange surfaces provided on the arms of the plurality of robots are joined to each other and the joint location is moved to the measurement point. Is performed on three or more measurement points that do not exist on the same straight line, and the measurement data of each robot acquired at each measurement point is calculated to calculate the relative position between multiple robots. did. As a result, the joint location is moved to the measurement point in a state in which the flange surfaces of the plurality of robots are joined, so that the position and position of the other robot can be tracked (synchronized) following the change in the position and posture of one robot. The posture can be changed, and the point taught by one robot and the point taught by another robot can be surely made the same. Therefore, when measuring at three measurement points that do not have redundancy, the relative positions between the plurality of robots can be accurately calculated. Moreover, even when measuring at four or more measurement points in order to provide redundancy, the flange surfaces are joined to each other, so that it is difficult to generate a deviation when moving to four or more measurement points. And the relative position between the plurality of robots can be calculated accurately and quickly.

  According to the second aspect of the present invention, the flange surfaces are joined by moving the arm of at least one robot set in an operation mode that operates by remote teaching among a plurality of robots. As a result, as a method of changing the position and posture of the robot, a method by remote teaching (a method in which the operator changes the position and posture by remote operation by operating a teaching pendant without directly touching the robot) and a method by direct teaching There is a method (manually touching the robot to apply external force to change the position and posture manually), but the former can change the position and posture more finely than the latter, so remote teaching The flange surfaces can be joined to each other while finely adjusting the position and posture of the robot flange set to the operation mode operated by the above, and the flange surfaces can be joined accurately.

  According to the invention described in claim 3, after moving the arms of at least one robot set in the operation mode operated by direct teaching among a plurality of robots to bring the flanges close to each other, remote teaching among the plurality of robots is performed. At least one robot arm set to an operation mode that operates according to the above is moved to join the flange surfaces together. As a result, even when the flanges of multiple robots are far apart, an external force is applied to the robot set to the operation mode that operates by direct teaching to move the flange of the robot to the vicinity of the flange of another robot. Then, the flange surfaces can be joined accurately and quickly by performing the method described in claim 2.

  According to the invention described in claim 4, the flange surface provided on the arm of one of the plurality of robots and one joining surface of the joining jig are joined together, and the other of the plurality of robots is joined. Measurement data representing the position and orientation of each robot is obtained with the flange surface provided on the robot arm and the other joint surface of the joining jig joined, and one of the joints moved to the measurement point. The operation to be performed is performed on three or more measurement points that do not exist on the same straight line, and the measurement data of each robot acquired at each measurement point is calculated to calculate the relative position between the plurality of robots. As a result, the flange surface of one robot among the plurality of robots and one joint surface of the joining jig are joined, and the flange surface of another robot and the other joining surface of the joining jig are joined. Since one of the joints is moved to the measurement point, it can follow (synchronize) changing the position and posture of one robot and change the position and posture of another robot via the joint jig. The point taught by one robot and the point taught by another robot can be reliably made the same. Therefore, even in a configuration in which a plurality of robots are connected via a joining jig, in the same manner as described in claim 1, a plurality of robots are measured when measuring at three measurement points without redundancy. The relative position between the robots can be calculated accurately. Moreover, in this case as well, even if measurement is performed at four or more measurement points in order to provide redundancy, the flange surface and the bonding surface of the bonding jig are joined, so that four or more measurement points are used. It is possible to make it difficult for deviations to occur during movement, and it is possible to calculate the relative positions between a plurality of robots accurately and quickly.

  According to the fifth aspect of the present invention, the flange surface and the joining surface of the joining jig are joined by moving the arm of at least one robot set in the operation mode operated by remote teaching among the plurality of robots. I made it. As a result, it is possible to join the flange surface of the robot and the joining surface of the joining jig while finely adjusting the position and posture of the robot flange set to the operation mode operated by remote teaching. It is possible to accurately join the joining surface.

  According to the invention described in claim 6, after moving the arm of at least one robot set to the operation mode operated by direct teaching among a plurality of robots to bring the flange and the joining jig closer, The operation mode is set to operate by remote teaching, and the robot arm set to the operation mode to operate by remote teaching is moved to join the flange surface and the joining surface of the joining jig. As a result, even when the flanges of multiple robots and the joining jig are far apart, external force is applied to the robot set to the operation mode that operates by direct teaching, and the flanges of the robots are placed near the joining jig. The flange surface and the joining surface of the joining jig can be joined accurately and quickly by moving and approaching, and then carrying out the method described in claim 5 described above.

  According to the seventh aspect of the present invention, all of the plurality of robots are set to an operation mode that operates by direct teaching, and at least one arm of the plurality of robots set to the operation mode that operates by the direct teaching is moved. The joint was moved to the measurement point. Thus, the relative position between the plurality of robots can be accurately calculated when the operator directly touches the robot set to the operation mode that operates by direct teaching and gives an external force.

  According to the invention described in claim 8, at least one of a plurality of robots is set to an operation mode that operates by remote teaching, and the robot arm set to the operation mode that operates by remote teaching is moved and joined. The point was moved to the measurement point. Thereby, the relative position between the plurality of robots can be accurately calculated by operating the teaching pendant, for example, without the operator directly touching the robot set to the operation mode operated by remote teaching.

(First embodiment)
Hereinafter, as a first embodiment of the present invention, a case where a relative position between two robots is calculated will be described with reference to FIGS. 1 to 3. FIG. 1 shows a mode in which a first robot 1 and a second robot 2 are arranged. The first robot 1 and the second robot 2 are arranged close to each other. The first robot 1 and the second robot 2 work in cooperation. For example, the first robot 1 and the second robot 2 hold the work on the workbench at the same time and move it from the workbench to the pallet or store it. Grasping a workpiece at the same time, removing it from the pallet and moving it to the work table.

  The first robot 1 is, for example, a 6-axis vertical articulated type, and includes a base 11 fixed to the floor, a shoulder portion 12 supported by the base 11 so as to be able to turn in the horizontal direction, and a shoulder portion 12. The lower arm 13 is supported so as to be pivotable in the vertical direction, the first upper arm 14 is supported so as to be pivotable in the vertical direction on the lower arm 13, and the tip of the first upper arm 14 is twisted and rotated. The second upper arm 15 supported so as to be able to rotate, the wrist 16 supported so as to be rotatable in the vertical direction by the second upper arm 15, and the flange supported so as to be rotatable (twisted) by the wrist 16. 17. The shoulder portion 12, the lower arm 13, the first upper arm 14, the second upper arm 15, the wrist 16 and the flange 17 including the base 11 function as links. A hand (not shown) for gripping the workpiece can be attached to the flange 17 that functions as a state-of-the-art link.

  The second robot 2 has the same configuration as the first robot 1 described above. That is, the second robot 2 is, for example, a six-axis vertical articulated type, and includes a base 21 fixed to the floor, a shoulder portion 22 supported by the base 21 so as to be able to turn in the horizontal direction, and a shoulder. A lower arm 23 supported by the portion 22 so as to be pivotable in the vertical direction, a first upper arm 24 supported by the lower arm 23 so as to be pivotable in the vertical direction, and a distal end portion of the first upper arm 24; The second upper arm 25 supported to be twisted and rotated, the wrist 26 supported to be vertically rotatable on the second upper arm 25, and the wrist 26 to be rotatably (twisted) supported. And a flange 27. The shoulder portion 22, the lower arm 23, the first upper arm 24, the second upper arm 25, the wrist 26, and the flange 27 including the base 21 function as links. A hand (not shown) for gripping a workpiece can be attached to the flange 27 that functions as the most advanced link.

  FIG. 2 schematically shows an electrical connection mode of the first robot 1 and the second robot 2 described above. The first control device 3 transmits control data to the first robot 1 to control its operation and receives and acquires various data from the first robot 1 and stores an operation program. ROM, CPU that reads and executes an operation program from ROM, a drive circuit that drives each link 11 to 17 of the first robot 1, a detection circuit that detects the position and posture of the first robot 1, and an operator that operates A communication circuit for communicating with the first teaching pendant 5 and other robots is provided.

  In this case, the operator can set the operation mode of the first robot 1 by operating the first teaching pendant 5, and the operation mode (remote teaching operation mode) operated by remote teaching as the operation mode and direct teaching. It is possible to set the operation mode (direct teaching operation mode) that operates. The remote teaching here is a method in which the operator operates the first teaching pendant 5 without directly touching the first robot 1 to change the position and posture by remote operation. This is a method in which a person directly touches the first robot 1 and applies an external force to change the position and posture manually.

  The second control device 4 has the same configuration as the first control device 3 described above. That is, the second control device 4 transmits control data to the second robot 2 to control the operation and receives and acquires various data from the second robot 2 and stores an operation program. ROM, a CPU that reads and executes an operation program from the ROM, a drive circuit that drives each link 21 to 27 of the second robot 2, a detection circuit that detects the position and posture of the second robot 2, and an operator A second teaching pendant 6 to be operated and a communication circuit for communicating with other robots are provided.

  Also in this case, the operator can set the operation mode of the second robot 2 by operating the second teaching pendant 6, and the operation mode (remote teaching operation mode) operated by remote teaching as the operation mode and direct An operation mode that operates by teaching (direct teaching operation mode) can be set.

  Now, it is necessary to calculate the relative positions (positions and postures) of the first robot 1 and the second robot 2 before the first robot 1 and the second robot 2 work in cooperation. In this embodiment, the relative positions of the first robot 1 and the second robot 2 are calculated according to the procedure shown in FIG.

  First, the flange surface 17a of the first robot 1 and the flange surface 27a of the second robot 2 are joined (step S1). In this case, as a method of joining the flange surfaces 17a and 27a, one of the first robot 1 and the second robot 2 is set to the remote teaching operation mode, and the robot set to the remote teaching operation mode is used. There is a method of joining the flange surfaces 17a and 27a by operating the corresponding teaching pendant.

  Further, if the flanges 17 and 27 are largely separated from each other, either the first robot 1 or the second robot 2 is set to the direct operation mode, and the robot set to the direct teaching operation mode is set. By applying an external force, the flange of the robot is moved closer to the flange of another robot, and then either the first robot 1 or the second robot 2 is set to the remote teaching operation mode, There is a method of joining the flange surfaces 17a and 27a together by operating a teaching pendant corresponding to the robot set in the remote teaching operation mode. In addition, in order to hold | maintain joining of the flange surfaces 17a and 27a reliably, you may fix both by screwing, for example.

  Next, one of the operation modes of the first robot 1 and the second robot 2 is set (step S2). That is, as a subsequent process after this, the joint location where the flange surfaces 17a, 27a are joined is moved to the measurement point, but the operation mode is set according to the method of moving the joint location to the measurement point, The joint location where the flange surfaces 17a and 27a are joined is moved to the measurement point (step S3).

  Specifically, if the first robot 1 is set to the remote teaching operation mode, the first teaching pendant 5 corresponding to the first robot 1 is operated to join the flange surfaces 17a and 27a together. If the joint is moved to the measurement point and the first robot 1 is set to the direct teaching operation mode, an external force is applied to the first robot 1 to join the flange surfaces 17a and 27a together. The location will be moved to the measurement point. If the second robot 2 is set to the remote teaching operation mode, the second teaching pendant 6 corresponding to the second robot 2 is operated, and the joint portion where the flange surfaces 17a and 27a are joined is determined. If the second robot 2 is set to the direct teaching operation mode when the second robot 2 is set to the direct teaching operation mode, an external force is applied to the second robot 2 to measure the joint portion where the flange surfaces 17a and 27a are joined. It will be moved to the point.

  At this time, since the flange surfaces 17a and 27a are joined, the operation of changing the position and posture of the first robot 1 and the operation of changing the position and posture of the second robot 2 follow (synchronize). It will be. The robots 1 and 2 are normally operated in the remote teaching operation mode. When the operator sets the direct teaching operation mode, the robot 1 and 2 operate in the direct teaching operation mode. When the setting is canceled, the remote teaching operation mode may be restored to operate.

  Next, measurement data representing the positions and postures of the first robot 1 and the second robot 2 are acquired in a state where the joint is moved to the measurement point in this way (step S4). Then, the measurement data is acquired by changing the measurement points so as to satisfy the conditions that do not exist on the same straight line, and the measurement data of each robot 1 and 2 is obtained at three or more measurement points that do not exist on the same straight line ( "YES" in step S5), the measurement data of each robot 1 and 2 acquired at each measurement point is calculated to calculate the relative position between the robots 1 and 2 (step S6).

  As described above, according to the first embodiment, the flange surface 17a of the first robot 1 and the flange surface 27a of the second robot 2 are joined, and the joint location is moved to the measurement point. To obtain the measurement data representing the position and orientation of each robot 1 and 2, and calculate the measurement data of each robot 1 and 2 obtained at three or more measurement points that do not exist on the same straight line. Since the relative position of the first robot 1 is calculated, the position and posture of the second robot 2 can be changed following the change of the position and posture of the first robot 1. The point taught and the point taught by the second robot 2 can be reliably made the same. Therefore, the relative position between the robots 1 and 2 can be accurately calculated when measurement is performed at three measurement points that do not have redundancy. Moreover, even when measurement is performed at four or more measurement points in order to provide redundancy, the flange surfaces 17a and 27a are joined to each other, so that a deviation occurs when moving to four or more measurement points. The relative position between the robots 1 and 2 can be calculated accurately and quickly.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. In addition, description is abbreviate | omitted about the same part as above-mentioned 1st Embodiment, and a different part is demonstrated. In the first embodiment described above, the flange surfaces are joined to each other. On the other hand, the second embodiment is a joining jig made of a material having high rigidity (which cannot be easily deformed). Is used to join the flange surface of one robot and the joint surface on one end side of the joining jig, and join the flange surface of another robot and the joint surface on the other end side of the joining jig.

  In other words, the second embodiment corresponds to a case where the first robot 1 and the second robot 2 are arranged largely apart from each other and the flange surfaces 17a and 27a cannot be joined to each other. is there. In the present embodiment, a long joining jig 7 as shown in FIG. 4 is used as a joining jig, and the relative positions of the first robot 1 and the second robot 2 are calculated according to the procedure shown in FIG. .

  First, the flange surface 17a of the first robot 1 and the joining surface 7a on one end side of the joining jig 7 are joined (step S11). In this case, since the joining jig 7 in the free state is attached to the flange 17 of the first robot 1, the joining jig 7 in the free state is brought close to the flange 17 of the first robot 1 and the flange surface 17a and the joining surface 7a on one end side of the joining jig 7 are joined.

  Next, the flange surface 27a of the second robot 2 and the joining surface 7b on the other end side of the joining jig 7 are joined (step S12). In this case, as a method of joining the flange surface 27a and the joining surface 7b on the other end side of the joining jig 7, the joining jig 7 which is not in a free state by being attached to the flange 17 of the first robot 1 is used. Since the second robot 2 is attached to the flange 27 of the second robot 2, the second robot 2 is set to the remote teaching operation mode, and the second teaching pendant corresponding to the second robot 2 set to the remote teaching operation mode is set. 6, there is a method of joining the flange surface 27 a and the joining surface 7 b on the other end side of the joining jig 7.

  If the flange 27 and the joining jig 7 are largely separated, the second robot 2 is set to the direct operation mode, and an external force is applied to the second robot 2 set to the direct teaching operation mode. As a result, the flange 27 of the second robot 2 is moved closer to the joining jig 7, and then the second robot is set to the remote teaching operation mode, and the second teaching operation is set to the remote teaching operation mode. There is a method of joining the flange surface 27 a and the joining surface 7 b on the other end side of the joining jig 7 by operating the second teaching pendant 6 corresponding to the robot 2. In this case as well, in order to securely hold the joint between the flange surface 17a and the joint surface 7a, for example, both may be fixed by screwing, and the joint between the flange surface 27a and the joint surface 7b is securely held. Therefore, for example, both may be fixed by screwing.

  Next, also in this case, the operation mode of any one of the first robot 1 and the second robot 2 is set (step S13), and the joint location where the flange surface 17a and the joint surface 7a are joined, and the flange surface 27a, One of the joints joined to the joint surface 7b is moved to the measurement point (step S14), and the first robot 1 and the second robot 2 are moved in a state where any one of the joints is moved to the measurement point. Measurement data representing the position and orientation is acquired (step S15). At this time, since the flange surface 17a and the joint surface 7a are joined and the flange surface 27a and the joint surface 7b are joined, the operation of changing the position and posture of the first robot 1 and the second robot 2 The movement of the position and orientation is followed (synchronized) via the joining jig 7.

  Then, the measurement data is acquired by changing the measurement points so as to satisfy the conditions that do not exist on the same straight line, and the measurement data of each robot 1 and 2 is obtained at three or more measurement points that do not exist on the same straight line ( "YES" in step S16), the measurement data of each robot 1 and 2 acquired at each measurement point is calculated to calculate the relative position between the robots 1 and 2 (step S17).

  As described above, according to the second embodiment, the flange surface 17a of the first robot 1 and the joint surface 7a on one end side of the joining jig 7 are joined and the flange surface 27a of the second robot 2 is joined. And the joint surface 7b on the other end side of the joining jig 7 are joined, and measurement data representing the position and orientation of each robot 1 and 2 is acquired in a state where any joint location is moved to the measurement point. Since the measurement data of the robots 1 and 2 acquired at three or more measurement points that do not exist on a straight line is calculated and the relative position between the robots 1 and 2 is calculated, the position of the first robot 1 and The position and posture of the second robot 2 can be changed via the joining jig 7 following the change of posture, and the point taught by the first robot 1 and the second robot 2 teach. It is possible to ensure that the points are the same. Therefore, even in the configuration in which the robots 1 and 2 are connected via the joining jig 7, the measurement is performed at three measurement points that do not have redundancy in the same manner as described in the first embodiment. In this case, the relative position between the robots 1 and 2 can be accurately calculated. Moreover, even when measurement is performed at four or more measurement points in order to provide redundancy, the flange surface 17a and the joint surface 7a are joined and the flange surface 27a and the joint surface 7b are joined. It is possible to make it difficult for deviation to occur when moving to a measurement point that is greater than or equal to the point, and the relative position between the robots 1 and 2 can be calculated accurately and quickly.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be modified or expanded as follows.
In the second embodiment, three or more robot flanges are joined to one joining member, or two or more joining members are connected, so that the relative position between the three or more robots is increased. May be configured to calculate.
The configuration may be such that one control device transmits control data to two or more robots to control the operation, and receives and acquires various data from two or more robots.

The 1st Embodiment of the present invention is shown and the figure which shows the mode where the flange surfaces of a robot are joined. The figure which shows the electrical connection aspect of a robot roughly Flow chart showing the procedure for calculating the relative position The figure which shows the 2nd Embodiment of this invention and shows the aspect by which the flange surface of a robot and the joining surface of a joining jig are joined. 3 equivalent figure

Explanation of symbols

  In the drawings, 1 and 2 are robots, 13 to 15 and 23 to 25 are arms, 17 and 27 are flanges, 17a and 27a are flange surfaces, 7 is a joining jig, and 7a and 7b are joining surfaces.

Claims (8)

  There is no work on the same straight line to acquire measurement data representing the position and posture of each robot while joining the flange surfaces provided on the arms of multiple robots and moving the joints to the measurement points. A method for calculating a relative position between a plurality of robots, wherein the relative position between the plurality of robots is calculated by calculating the measurement data of each robot acquired at each of the measurement points and calculating the relative position between the plurality of robots. .   2. The relative position calculation method between a plurality of robots according to claim 1, wherein the flange surfaces are joined by moving an arm of at least one robot set in an operation mode operated by remote teaching among a plurality of robots. .   At least one of the plurality of robots set to the operation mode operated by remote teaching after moving the arm of at least one robot set to the operation mode operated by direct teaching and bringing the flanges close to each other. 3. The relative position calculation method between a plurality of robots according to claim 2, wherein the flange surfaces are joined by moving the arms of two robots.   The flange surface provided on the arm of one of the plurality of robots and the joint surface of one of the joining jigs are joined together, and the flange surface provided on the arm of the other robot among the plurality of robots There is no work on the same straight line for obtaining measurement data representing the position and posture of each robot in a state in which any other joint surface is joined to the measurement point by joining the other joining surfaces of the joining jig. A relative position calculation method between a plurality of robots, wherein the relative position between a plurality of robots is calculated by calculating measurement data of each robot obtained at each measurement point and calculating relative positions between the plurality of robots.   5. The flange surface and a joining surface of the joining jig are joined by moving an arm of at least one robot set in an operation mode that operates by remote teaching among a plurality of robots. A relative position calculation method between multiple robots.   Move the arm of at least one robot that is set to an operation mode that operates by direct teaching among multiple robots to bring the flange and the joining jig closer, and then set the robot to an operation mode that operates by remote teaching 6. The relative movement between a plurality of robots according to claim 5, wherein the robot arm set to an operation mode operated by the remote teaching is moved to join the flange surface and the joining surface of the joining jig. Position calculation method.   All robots are set to an operation mode that operates by direct teaching, and at least one arm of the plurality of robots that are set to an operation mode that operates by direct teaching is moved to move the joint to the measurement point. The method for calculating a relative position between a plurality of robots according to any one of claims 1 to 6.   At least one of a plurality of robots is set to an operation mode that operates by remote teaching, and the robot arm set to the operation mode that operates by remote teaching is moved to move the joint to a measurement point. A relative position calculation method between a plurality of robots according to any one of claims 1 to 6.

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