JP7140826B2 - Grip control device - Google Patents

Description

The present invention relates to a gripping control device for gripping a linear object using a robot hand.

2. Description of the Related Art Robots that recognize an object with a three-dimensional camera or the like and hold it autonomously are becoming more popular. Regarding gripping a linear object, for example, Japanese Patent Application Laid-Open No. 2014-176917 (Patent Document 1) discloses a robot apparatus for assembling a linear object, in which a fixed end of a linear object is fixed at one end. A device is described in which, after gripping the vicinity, the gripping part is slid along a predetermined trajectory to move to the other end. It is said that this makes it possible to quickly grasp the other end of an electric wire, which is an example of a linear object, which is difficult to accurately estimate due to the peculiarity of the wire.

Japanese Patent Application Laid-Open No. 2016-192138 (Patent Document 2) discloses an invention relating to a wire harness manufacturing method and an image processing method. is performed to specify the machining position.

JP 2014-176917 A JP 2016-192138 A

It is conceivable that a gripping portion of a robot hand grips a linear object, such as a wire harness, and performs control to move the tip of the wire harness to a predetermined target position. For example, it is assumed that the tip of the wire harness is inserted into a through-hole provided in the object.

In this case, since the wire harness often has relatively low rigidity, if the wire harness is gripped at only one point using the gripping portion of the robot hand, the distal end side from the gripping portion becomes unstable. Furthermore, the wire harness may be continuously connected to the opposite side (rear end side) of the wire harness gripped by the gripping portion. In this case, the weight of the wire harness on the rear end side is added to the gripping portion of the robot hand, and there is concern that the gripping portion of the wire harness may become unstable.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems, and to provide a gripping control device having a configuration capable of stably gripping a linear object when the gripping portion of a robot hand grips the linear object. to provide.

This gripping control device is a gripping control device that notifies a robot equipped with a linear object gripping device capable of gripping a linear object of gripping information of the linear object to the robot. a three-dimensional camera that obtains a three-dimensional shape of the three-dimensional shape, recognizes a first gripping position based on the three-dimensional shape, calculates a second gripping position by a predetermined method, and calculates the first gripping position and the second gripping position and a processing unit that notifies the robot of.

In another aspect, the second gripping position is calculated based on at least one of the three-dimensional shape, the shape of the linear object gripping device, and the range of motion of the linear object gripping device.

In another aspect, the processing unit also notifies the gripping postures when the linear object gripping device grips the first gripping position and the second gripping position.

In another aspect, the gripping posture is a posture in which the linear object and the gripping portion of the linear object gripping device are perpendicular to each other at the first gripping position.

In another embodiment, the linear article is a multifilamentary wire in which a plurality of thin wires are covered with a covering material, and includes an exposed thin wire portion in which the plurality of thin wires are exposed and a covered bundle portion covered with the covering material. wherein the first gripping position is located at the exposed thin wire portion, and the second gripping position is located at the covered bundle portion.

In another aspect, the robot is a single multi-joint robot, and the processing unit sets the first gripping position and the second gripping position that can be gripped by a robot hand provided in the multi-joint robot to the multi-joint robot. Notify the joint robot.

According to this gripping control device, it is possible to provide a gripping control device having a configuration capable of stably gripping a linear object when the gripping portion of the robot hand grips the linear object.

It is a figure which shows the whole system which performs the linear object grasping method in related technology. It is a process flow diagram of a linear object gripping method in the related art. It is a process flow diagram of a determination process of a linear object gripping method in the related art. 1 is a diagram showing a first interference region and a first extended interference region in related art; FIG. FIG. 2 is a diagram showing a second interference region and a second extended interference region in related art; It is a figure for demonstrating the magnitude|size of the 1st interference area|region in related technology. It is a figure for demonstrating the 1st determination process in related technology. It is a figure for demonstrating the 1st preliminary|backup determination process in related technology. FIG. 4 is a schematic diagram showing a gripping position of a linear object; 1 is a schematic diagram showing a configuration of a linear object gripping device according to an embodiment; FIG.

A grip control device according to an embodiment of the present invention will be described below with reference to the drawings. In the embodiments described below, when referring to the number, amount, etc., the scope of the present invention is not necessarily limited to the number, amount, etc., unless otherwise specified. The same reference numbers are given to the same parts and equivalent parts, and redundant description may not be repeated. It is planned from the beginning to use the configurations in the embodiments in combination as appropriate. In the drawings, the actual dimensional ratios are not shown, but the ratios are partially changed in order to facilitate understanding of the structure.

In the following description, a wire is used as an example of the linear object, but the wire is not limited to the wire. A linear object in this description may be any object having an elongated shape. Examples of linear objects include electric wires, wire harnesses, solder, cords, threads, fibers, glass fibers, optical fibers, tubes, dried noodles, and the like. It is not limited to an electric wire in which thin wires are bundled, but also includes an electric wire or the like composed of a single wire. In particular, in the case of a linear object whose shape changes due to bending or the like, or a linear object that is not straight, the effects of the present embodiment are more pronounced.

(Related technology: linear object gripping method and control device)
Hereinafter, an example of a linear object gripping method and a control device will be described as related art with reference to FIGS. 1 to 8. FIG.

In FIG. 1, an overall system 10 for carrying out a linear object gripping method has a robot 20, a three-dimensional camera 31, and a control device 32. As shown in FIG. A wire harness W including electric wires W1, W2, and W3 is arranged in the work space.

As the robot 20, a well-known articulated robot can be preferably used. A robot hand 22 is provided at the tip of the robot arm 21 , and a linear object is gripped by a pair of gripping portions 23 , 23 of the robot hand 22 .

The three-dimensional camera 31 is not particularly limited as long as it can measure the three-dimensional shapes of the electric wire W1, the electric wire W2, and the electric wire W3. A stereo camera is preferably used. A stereo camera is preferable for measuring the three-dimensional shape of a linear object at high speed.

The stereo camera includes two cameras, and the corresponding points of the points to be measured on the two images taken from different viewpoints are obtained. Calculate the position. Regarding the three-dimensional measurement of linear objects by the stereo method, for example, Japanese Patent Application Laid-Open No. 2-309202 discloses that a large number of linear objects are imaged by two cameras, and the inclination of the bright lines and the distance between the bright lines in the two images are measured. It is described that the corresponding points are determined by collation using the distance of .

In the stereo method, a straight line that connects the viewpoint of one image and the measurement point is projected onto the other image (see Japanese Patent Application No. 2017-221045). Corresponding points on the image are always projected onto the epipolar line on the other image.

Using this fact, in order to find the corresponding point of a certain point on the linear object, it is sufficient to find the intersection of the linear object and the epipolar line on the other image, and the three-dimensional shape of the linear object can be obtained at high speed. can be measured. If the linear objects are colored differently from each other, a color camera can be used to extract the corresponding color from the image and then find the corresponding points, thereby speeding up the three-dimensional shape of each linear object. can be asked for.

The control device 32 communicates with the three-dimensional camera 31 through a communication unit (not shown), and obtains the three-dimensional shapes of the electric wire W1, the electric wire W2, and the electric wire W3 from the stereo camera. Based on the three-dimensional shape obtained from the stereo camera, the control device determines whether or not the robot hand 22 interferes with another linear object when grasping the linear object by a calculation unit (not shown), and grasps the linear object. Various operations are performed to determine the target linear object to be scaled.

The control device notifies the robot 20 of the gripping position of the target linear object to be gripped based on the calculation result via the communication unit. In addition to directly notifying the robot 20 of the gripping position, another device (for example, a robot controller, a control personal computer, etc.) is provided between the control device 32 and the robot 20 to control the operation of the robot. You can notify us.

The linear object gripping method of the related art will be described below with reference to FIG. The linear object gripping method of this related art comprises a step (S1) of measuring three-dimensional shapes of a plurality of electric wires W1, W2 and W3, and a robot hand 22 picking up a linear object based on the measured three-dimensional shapes. It includes a determination step (S2) of determining whether or not another linear object interferes when gripped, and a step (S3) of gripping the target linear object determined based on the determination result in the determination step S2.

A step S1 of measuring the three-dimensional shapes of the plurality of electric wires W1, W2, and W3 is performed by the three-dimensional camera 31. FIG. The stereo camera captures an image of a work space in which the linear object is present, and arithmetically processes the two images to acquire the three-dimensional shapes of the electric wires W1, W2, and W3. A three-dimensional shape of a linear object is represented by an orthogonal coordinate system or an oblique coordinate system, preferably by an orthogonal coordinate system.

The determination step S2 is performed by the control device 32 . Details of the determination process will be described later.

Step S<b>3 of gripping the target linear object is performed by the robot 20 . The robot is notified of the gripping position of the target linear object to be gripped by the control device 32, and moves the robot arm 21 and the robot hand 22 to perform gripping operations.

The determination step S2 will be described in detail below.
Referring to FIG. 3, in the determination step S2 of the related art, acquisition of the three-dimensional shape of the linear object (S21), selection of the linear object of interest (S22), determination of the gripping position of the linear object of interest (S23). ), acquisition of the robot hand standby position (S24), setting of various interference areas (S51 to S54), and various interference determinations (S61 to S64).

The control device 32 first acquires the three-dimensional shapes of the electric wire W1, the electric wire W2, and the electric wire W3 from the three-dimensional camera 31 (S21).

Next, the control device 32 selects a target linear object to be gripped by the robot hand 22 (S22). In the following description, the target wire object to be gripped by the wire W1, the wire W2 and the wire W3 are described as wire objects other than the target wire object (other wire objects). The control device may receive a specification such as the color of the electric wire from the outside and determine the target linear object based on the specification. Preferably, the control device selects the target linear object for the autonomous reference number (see Japanese Patent Application No. 2017-221045).

For example, when the electric wire W1, the electric wire W2, and the electric wire W3 are placed on a table, the highest position based on the obtained three-dimensional shape, that is, the highest linear object is selected as the target linear object. can be done. This is because even when linear objects are placed on top of each other, the higher the linear object is, the lower the probability that other linear objects will interfere when the linear object is gripped.

Next, the control device 32 determines the gripping position of the wire W1 of interest (S23). For example, based on a predetermined condition such as how many mm from the tip of the target linear object, the control device calculates the gripping position of the target linear object as three-dimensional coordinates.

Next, the control device 32 acquires the standby position of the robot hand 22 (S24). When the standby position of the robot hand 22 is determined in advance, its coordinates are acquired as the standby position. When the standby position is determined based on the three-dimensional shape of the linear object, for example, when it is determined at a predetermined distance above the linear object, the standby position is obtained by calculation.

The control device 32 acquires the current position of the robot hand 22 from the robot 20, and moves the robot hand 22 to the standby position when the current position of the robot hand 22 is different from the standby position. A line segment connecting the standby position of the robot hand 22 and the gripping position of the electric wire W1 gives an approximate movement path when the robot hand 22 executes the gripping operation.

Next, the control device 32 sets several interference areas including the gripping position of the target linear object for interference judgment between the robot hand 22 and the other electric wires W2 and W3. In FIG. 3, the first interference area, the first extended interference area, the second interference area, and the second extended interference area are set in this order. Interference determination is performed for each of all the other linear objects to determine whether or not the other linear object is included in each of the interference areas.

Interference determination for each linear object is made by shifting a point or line segment on the linear object in the length direction and determining whether the point is within the interference area or whether the line segment intersects the interference area. can be done by In FIG. 3, the second preliminary determination for the second extended interference region, the second determination for the second interference region, the first preliminary determination for the first extended interference region, and the first determination for the first interference region are performed in this order. Although different from the order in FIG. 3, each interference area and interference determination for that area will be described below.

Referring to FIG. 4, a first determination step S61 for the first interference area 51 determines whether the robot hand 22 interferes with the other wires W2 and W3 when gripping the wire W1.

The first interference area 51 is a planar area including the gripping position P of the electric wire W1 and having a predetermined shape and size. The first interference area preferably includes the grip position P at its center. Although the shape of the first interference region is not particularly limited, it is preferably polygonal, circular, or elliptical. If the first interference region is polygonal, it is preferably quadrangular, more preferably square. This is because the calculation load is lightened and high-speed determination is possible. When the first interference area is a polygon, a square having sides parallel to a plane formed by any two axes of a coordinate system representing the three-dimensional shape of a linear object (hereinafter simply referred to as the "coordinate system") is the first One interference region is particularly preferred.

This is because the efficiency of the first preliminary determination can be improved by making the first extended interference region, which will be described later, smaller. If the first interference region is not polygonal, it is preferably circular. Similarly, this is because the calculation load is lightened, and high-speed determination is possible.

If the size of the first interference region 51 is too large, the probability of erroneous determination of interference when there is no actual interference increases. Referring to FIG. 6, if the smallest circle circumscribing the maximum cross section of robot hand 22 is circle C1, the first interference area is preferably included in a circle having a diameter 2.0 times as large as circle C1. It is a size, and more preferably a size that is included in a circle having the same size as the circle C1.

On the other hand, if the first interference region is too small, the probability of erroneously determining that there is no interference when there is actual interference increases. Referring to FIG. 6, if the smallest circle circumscribing the maximum cross-section of gripping portion 23 operated by robot hand 22 to grip a linear object is circle C2, the first interference region is preferably circle C2 (See Japanese Patent Application No. 2017-221045).

The first interference region 51 is preferably perpendicular to the wire W1. The expression that the first interference region is perpendicular to the linear object of interest means that the direction in which the linear object of interest extends at the grip position P is perpendicular to the first interference region. This is because the equation of the plane containing the first interference region can be easily obtained. Also, when gripping a linear object with the robot hand 22, it is often the case that the linear object is gripped directly from the side, that is, from a direction perpendicular to the linear object. When another linear object exists in the first interference area orthogonal to the linear object of interest, the robot hand 22 cannot grasp the linear object of interest even if the robot hand 22 does not grip the linear object of interest from the side. This is because there is a high probability of interference with the linear objects of

Referring to FIG. 7, the first determination step S61 can be performed by determining the intersection between the line segment L on the other target electric wire W2 and the first interference region 51. Referring to FIG. The line segment L can be a line segment between two adjacent points S and T in the point group representing the three-dimensional shape of the electric wire W2. If the line segment L intersects the first interference area, then some point on the line segment L is included in the first interference area. Intersection determination can be performed by a known method. For example, if the inner product of the normal vector N of the plane U including the first interference region 51 and the vectors PS and PT from the gripping position P to both ends S and T of the line segment L is taken, and the signs of the two inner products are different: A line segment L intersects the plane U. If the line segment L and the plane U intersect, it may be determined whether or not the intersection is within the first interference area 51 .

Referring to FIG. 4, the first preliminary determination step S62 for the first extended interference area 52 is performed prior to the first determination, and the case where the robot hand 22 and the other wires W2 and W3 do not interfere can be calculated at a higher speed. Do to discover in.

The first extended interference area 52 is a spatial area including the first interference area 51 . The shape and size of the first extended interference region are not particularly limited, but preferably the smallest hexahedron that includes the first interference region and has all sides parallel to one of the axes of the coordinate system is the first Set as 1 extended interference area. If the coordinate system is an orthogonal coordinate system, this hexahedron is a rectangular parallelepiped. As a result, the first preliminary determination can be performed simply by comparing the magnitudes of the coordinates.

Specifically, referring to FIG. 8, the coordinates of the eight vertices A to H of the first extended interference region 52 are as shown in FIG. zS), if x1 ≤ xS ≤ x2, y1 ≤ yS ≤ y2, and z1 ≤ zS ≤ z2, then point S is within the first extended interference region; 1 is outside the extended interference region.

Since the first extended interference area 52 includes the first interference area 51, the first determination can be omitted if the result of the first preliminary determination is that the hand does not interfere with another linear object.

Referring to FIG. 5, the second determination step (S63) for the second interference area 53 determines whether or not the robot hand 22 interferes with the other wires W2 and W3 on the path along which the robot hand 22 moves to the gripping position P of the wire W1. determine whether

The second interference area 53 is a planar area that includes a line segment PQ connecting the gripping position P of the wire W1 and the standby position Q of the robot hand 22, spreads on both sides of the line segment PQ, and has a predetermined width. The second interference region preferably includes a line segment PQ at the center in its width direction. The shape of the second interference region is not particularly limited, but is preferably rectangular or parallelogram, and more preferably rectangular with line segment PQ as the axis of symmetry. This is to lighten the computational load and speed up the determination.

If the width of the second interference region 53 is too wide, the probability of erroneous determination of interference when there is no actual interference increases. The width of the second interference area is preferably equal to or less than the diameter of circle C1 in FIG. On the other hand, if the width of the second interference region is too narrow, the probability of erroneously determining that there is no interference when there is interference in practice increases (see Japanese Patent Application No. 2017-221045). The width of the second interference area is preferably equal to or greater than the diameter of circle C2 in FIG.

The second interference region 53 is preferably set such that the angle of intersection with the wire W1 is maximized. This is because, when the robot hand 22 approaches the electric wire W1, the grasping portions 23, 23 often advance within such a plane.

As in the first determination step S61, the second determination step S63 can be performed by determining the intersection of the line segment L on the other target electric wire W2 and the second interference region 53. FIG.

The second preliminary determination step (S64) for the second extended interference area 54 is performed prior to the second determination, and is used to discover the case where the robot hand 22 does not interfere with the other electric wires W2 and W3 by faster calculation. do it on

A second extended interference area 54 is a spatial area that includes the second interference area 53 . The shape and size of the second extended interference region are not particularly limited, but preferably the smallest hexahedron that includes the second interference region and has all sides parallel to one of the axes of the coordinate system is the first 2 Set as an extended interference area. If the coordinate system is an orthogonal coordinate system, this hexahedron is a rectangular parallelepiped. As a result, the second preliminary determination can be performed simply by comparing the magnitudes of the coordinates.

Since the second extended interference area 54 includes the second interference area 53, the second determination can be omitted if the result of the second preliminary determination is that the hand does not interfere with another linear object.

The determination steps S61 to S64 are repeated while shifting the line segment L to be determined in the length direction of the electric wire W2, and when the interference determination with the other electric wire W2 is completed, the same processing is performed for the next other electric wire W3. do

When it is determined that none of the other electric wires W2 and W3 are included in the interference areas 51 to 54, the controller 32 determines that the robot hand 22 does not interfere with other linear objects when the robot hand 22 grips the gripping position of the electric wire W1. determine that there is no After that, the robot 20 is notified of the gripping position of the electric wire W1 as the target linear object.

When it is determined in either the first determination or the second determination that the line segment L is included in the first interference area or the second interference area, the control device 32 grips the gripping position of the electric wire W1 with the robot hand 22. It is determined that there is interference from other linear objects. The subsequent determination steps are omitted, the process returns to step S22, and the same process is repeated with a different linear object of interest. When the control device 32 autonomously selects the next target linear object, for example, based on the three-dimensional shapes of the electric wires W1 to W3 previously acquired from the three-dimensional camera 31, the next highest linear object is selected. An object can be selected as a line object of interest.

If it is determined that there is interference with other linear objects regardless of which linear object is focused, rotate the entire linear object to change its orientation, or shake or vibrate the linear object. Each step may be performed again after changing the positional relationship between the linear objects. The distance from the gripping position of each target linear object to the nearest other linear object may be calculated as an interference distance, and the linear objects having the longest interference distance may be gripped first. Accordingly, it is possible to instruct the robot to perform the gripping motions in the order in which the gripping is likely to be successful. The interference distance can be easily calculated by using the distance from the intersection of the first interference area or the second interference area and another linear object in the interference determination to the gripping position.

As described above, according to the linear object gripping method of the related art, the gripping operation is executed based on the determination result as to whether or not the linear object interferes with another linear object. One linear object (see Japanese Patent Application No. 2017-221045) can be selected from the robot hand 22 and gripped by the robot hand 22 .

The presence or absence of interference of the robot hand 22 with another linear object is determined by calculating the presence or absence of intersection with a polyhedron using the CAD data on the robot hand 22 side and the three-dimensional shape data of the linear object. good too. However, although this method is excellent in accuracy of determination, it is a time-consuming process.

In this related art, whether or not a linear object other than the linear object of interest exists in the first interference area can be determined by judging the intersection between the planar first interference area and the linear object, so the amount of calculation is reduced. The presence or absence of interference can be determined at high speed. When there is no linear object other than the target linear object within the first interference area, there is a high probability that the robot hand 22 can grip the target linear object without interfering with other linear objects. The same applies to the second interference area.

The order of performing each determination step is not particularly limited except that the first preliminary determination is performed prior to the first determination, and the second preliminary determination is performed prior to the second determination. In the above embodiment, the second determination step is performed first, and the first determination step is performed later, but this order may be reversed. In the above related art, all determination steps are performed for each line segment while shifting the line segment L in the length direction of the linear object. step), another determination step (for example, the second determination step) may be performed again for the same linear object.

In the above-described related art, the linear object of interest is selected (S22) prior to obtaining the standby position of the robot hand 22 (S24). You can choose a shape. In that case, the linear object closest to the standby position can be selected as the target linear object. A linear object having the shortest distance between the coordinates of the standby position and the coordinates of the gripping position of the linear object may be selected as the linear object closest to the standby position. This is preferable in that it is possible to preferentially select linear objects that are less likely to interfere with other linear objects when gripped.

The posture (gripping posture) when the robot hand 22 grips the linear object is preferably such that the gripping portion and the linear object form a substantially right angle. This is because, if the direction of the linear object on the tip side from the gripping position is substantially perpendicular to the gripping portion, the robot can be easily controlled when inserting the linear object into a processing machine or the like after gripping. Preferably, the posture of the robot hand 22 is adjusted so that the gripping portion and the linear object form a right angle when gripped at the standby position. After that, the robot hand 22 moves along the second interference area from the waiting position toward the gripping position. As a result, the posture of the robot hand 22, the direction of movement of the robot hand 22, and the directions of the planes of the first and second interference areas are matched, so that highly accurate interference determination is possible.

The robot hand 22 that grips the linear object according to the present embodiment may convey the linear object to various manufacturing apparatuses and processing apparatuses. For example, the tip of the gripped electric wire may be moved by the robot hand 22 and inserted into a coating stripping machine, a terminal crimping machine, or the like. You may use for the process which inserts the front-end|tip of an electric wire in various components, such as a connector, and manufactures a wire harness.

(Embodiment: gripping control device and linear object gripping device)
A case of gripping the linear object using the gripping portion 23 of the robot hand 22 described above will be examined. Specifically, in this embodiment, a device that controls the gripping posture and gripping position of the linear object by the gripping portion 23 of the robot hand 22 is called a gripping control device 40 .

Again, referring to FIG. 1, the gripping control device 40 recognizes the first gripping position H1 based on the three-dimensional camera 31 that acquires the three-dimensional shape of the wire harness W and the three-dimensional shape, which will be described below. a processing unit that calculates the second gripping position H2 by a predetermined method and notifies the robot 20 of the first gripping position H1 and the second gripping position H2. This processing unit may be included in the control device 32, or may be configured as a separate device. In this embodiment, the control device 32 includes a processing unit.

The processing unit acquires the three-dimensional shape of the linear object (wire harness W) from the three-dimensional camera 31 that acquires the three-dimensional shape of the linear object W1, and acquires the position of the tip of the linear object from this three-dimensional shape. Then, based on the position of the tip of the linear object, it is assumed that the robot 20 having the robot hand 22 is notified of information on the grip posture and grip position.

The overall system 10 shown in FIG. 1 is configured to have a robot 20 having a robot hand 22, a three-dimensional camera 31, and a control device 32. In FIG. This control device 32 may be a control device independent of the robot 20 and the three-dimensional camera 31 , a control device provided with the robot 20 , or a control device provided with the three-dimensional camera 31 .

Since this embodiment is a mechanism that can grip and handle a linear object at two positions with one robot arm 21, a mechanism for gripping a linear object at two positions using two robot arms can be used. Compared to , it is possible to achieve accurate transportation at lower cost and space for each stage. Although two three-dimensional cameras 31 are shown in FIG. good.

After the gripping position of the linear object is determined as described above, when the linear object is gripped using the gripping unit 23 of the robot hand 22, one point near the tip of the linear object is gripped. can be considered. However, since the rigidity of a linear object is relatively low in many cases, if the linear object is gripped only at one point using the gripping portion 23, the distal end side from the gripping portion 23 may become unstable. . In such a case, even if the linear object is gripped and moved to be inserted into a predetermined machining hole, there is a concern that the tip cannot be inserted because the tip side is unstable.

Furthermore, the linear object may be continuously connected to the opposite side (rear end side) of the linear object gripped by the gripping portion 23 . In this case, the weight of the linear object on the rear end side is applied to the gripping portion 23 of the robot hand, and there is concern that gripping of the linear object by the gripping portion 23 may become unstable.

When a linear object is grasped and moved to a predetermined position, there is concern that the linear object may come into contact with other parts or obstacles during movement due to bending of the linear object. When a robot grips a linear object and stores it in a specified case, it may not be possible to store the linear object in the specified case if the shape of the linear object becomes unexpected while it is being gripped. .

Therefore, in the present embodiment, a gripping control device and a linear object gripping device are provided with a configuration capable of gripping a linear object at two positions so that the linear object can be stably gripped and moved. will be described below.

A linear object gripping device 220 according to the present embodiment will be described with reference to FIGS. 9 and 10. FIG. The robot hand 22 described above includes a linear object gripping device 220 . FIG. 9 is a schematic diagram showing the gripping position of the linear object, and FIG. 10 is a schematic diagram showing the configuration of the linear object gripping device 220. As shown in FIG.

Referring to FIG. 9, a wire harness W in which an electric wire W1, an electric wire W2 and an electric wire W3 are bundled is used as a wire-shaped object used in the present embodiment. The wire W1, the wire W2, and the wire W3 are in a state of being exposed (exposed thin wire portion) by removing the covering from the tip portion of the covered bundle portion W10 of the wire harness W. As shown in FIG.

In this embodiment, it is assumed that the tip of the electric wire W1 is conveyed to a predetermined position. The linear object gripping device 220 has an exposed thin wire portion (first gripping position H1) located at a predetermined distance L1 from the tip side of the electric wire W1, and a position farther from the tip side of the wire harness W than the first gripping position H1. The coated bundle W10 at the position L1+L2 (second gripping position H2) is gripped.

Which wire to select and the first gripping position H1 of the selected wire W1 are determined by adopting the gripping position determination process described above. The second gripping position H2 of the covered bundle W10 is determined by a determination method or a calculation method described later. In this embodiment, the distance L1 from the tip of the wire W1 is set to about 10 mm as the first gripping position H1. A distance L2 between the first gripping position H1 and the second gripping position H2 was set to approximately 100 mm. The distance L1 and the distance L2 can be appropriately set to optimal distances according to the type and weight of the linear object.

Referring to FIG. 10, linear object gripping device 220 includes first gripping device 22A for gripping electric wire W1 at first gripping position H1 and second gripping device 22B for gripping wire harness W at second gripping position H2. include. The first gripping device 22A and the second gripping device 22B are integrally connected by a bridge member 25 . Furthermore, a connecting member 26 connected to the distal end side of the robot arm 21 is attached to the bridge member 25 .

The first gripping device 22A has a first main body device 24A. A pair of grip hands 23a, 23a for gripping the first gripping position H1 of the wire W1 is provided at the tip of the first main unit 24A.

The pair of grip hands 23a, 23a are provided so as to be openable and closable in the direction of arrow P in the figure by an actuator (not shown) provided inside the first main unit 24A. The opening and closing operations of the grip hands 23a, 23a are controlled by the control device 32 described above.

A flat member is used for the pair of grip hands 23a, 23a. As a result, even a wire W1 having a relatively small wire diameter can be stably gripped.

Like the first gripping device 22A, the second gripping device 22B also has a second main unit 24B. A pair of grip hands 23b, 23b for gripping the second gripping position H2 of the covering bundle W10 is provided at the tip of the second main unit 24B.

The pair of grip hands 23b, 23b are provided so as to be openable and closable in the direction of arrow P in the drawing by an actuator (not shown) provided inside the second main unit 24B. The opening and closing operations of the pair of grip hands 23b, 23b are controlled by the control device 32 described above.

In FIG. 10, if the direction in which the wire harness W extends is the X direction, the direction in which the first gripping device 22A and the second gripping device 22B are positioned is the Z direction orthogonal to the X direction. That is, the gripping posture of the wire harness is such that the wire harness and the gripping hands 23a, 23a and 23b, 23b, which are the gripping portions, are perpendicular to each other at the first gripping position and the second gripping position. The arrow P direction in the figure in which the pair of grip hands 23a, 23a and the pair of grip hands 23b, 23b open and close is the Y direction orthogonal to both the X direction and the Z direction. Here, even if "perpendicular" is not 90 degrees in the strict sense, it includes some errors within the range where the effects of the present embodiment described below can be obtained.

A flat member is used for the pair of grip hands 23b, 23b. As a result, even a wire W1 having a relatively small wire diameter can be stably gripped.

As described above, according to the linear object gripping device 220 of the present embodiment, the wire W1 is gripped at the first gripping position H1 by the first gripping device 22A, and the coated bundle portion W10 is gripped by the second gripping device 22B. . As a result, the linear object gripping device 220 holds the wire harness W at two positions. As a result, the wire harness W can be stably held, and the tip portion of the electric wire W1 can be accurately conveyed to a predetermined position using the robot hand 22 .

The second gripping position H2 is determined by providing the second gripping device 22B at a position a predetermined distance away from the first gripping position H1, but the determination method is not limited to this. For example, when another robot arm has already grasped a linear object (such as when receiving a wire harness from another robot arm), the second grasping position H2 is determined from the position information grasped by the other robot arm. You may

Further, the second gripping position H2 may be calculated based on at least one of the three-dimensional shape of the wire harness W, the shape of the linear object gripping device 220, and the range of motion of the linear object gripping device 220. “Determined based on the range of motion of the linear object gripping device 220” means that the movable range determination is performed to determine whether or not the second gripping position H2 is within the operation range of the robot 20 and the linear object gripping device 220. do If the determination result is outside the movable range, another gripping position may be re-determined as the second gripping position, or information (rotation, movement, etc.) for changing the posture of the wire harness W is notified to the robot 20 . may

The linear object to be gripped is not limited to the wire harness W. Wires, solders, strings, threads, fibers, glass fibers, optical fibers, tubes, dried noodles, and the like.

It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above description, and is intended to include all changes within the scope and meaning equivalent to the scope of the claims.

10 overall system, 20 robot, 21 robot arm, 22 robot hand, 31 three-dimensional camera (stereo camera), 32 control device, 40 grip control device, 51 first interference area, 52 first extended interference area, 53 second interference Region, 54 Second Extended Interference Region. 22A first gripping device 22B second gripping device 23 gripping part 23a, 23b gripping hand 24A first main unit 24B second main unit 25 bridge member 26 connecting member 220 linear object gripping device H1 first gripping position, H2 second gripping position;

Claims (6)

A gripping control device for notifying a robot equipped with a linear object gripping device capable of gripping a linear object of gripping information of the linear object to the robot,
a three-dimensional camera for acquiring the three-dimensional shape of the linear object;
a processing unit that recognizes a first gripping position based on the three-dimensional shape, calculates a second gripping position by a predetermined method, and notifies the robot of the first gripping position and the second gripping position;
A gripping control device comprising: the second gripping position is calculated based on at least one of the three-dimensional shape, the shape of the linear object gripping device, and the range of motion of the linear object gripping device;
A grip control device according to claim 1 . The processing unit also notifies a gripping posture when the linear object gripping device grips the first gripping position and the second gripping position.
3. A gripping control device according to claim 1 or 2. The gripping posture is a posture in which the linear object and the gripping portion of the linear object gripping device are perpendicular to each other at the first gripping position.
A grip control device according to claim 3. The linear object is a multifilamentary wire in which a plurality of thin wires are covered with a covering material, and includes an exposed thin wire portion in which the plurality of thin wires are exposed and a covered bundle portion covered with the covering material,
The first gripping position is located at the exposed thin wire portion,
The gripping control device according to any one of claims 1 to 4, wherein the second gripping position is located at the coated bundle portion. The robot is one articulated robot,
The processing unit notifies the articulated robot of the first gripping position and the second gripping position that can be gripped by a robot hand provided in the articulated robot.
The grip control device according to any one of claims 1 to 5.

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