JP7674124B2 - Robot Hand System - Google Patents

Description

The present invention relates to a light-projecting device, a light-projecting method, and a robot hand system.

Industrial robots equipped with robotic hands are widely used in industrial production sites to grasp objects. In order for a robotic hand to grasp or pick up an object, information is required regarding the distance between the robotic hand and the object, as well as information regarding the posture (tilt) of the object.

A technology for obtaining information regarding the distance between a robot hand and an object to be grasped is disclosed, for example, in Patent Document 1. In this technology, a robot hand has multiple fingers for grasping an object to be grasped, and two different fingers irradiate collimated light of different colors so that they intersect near the object to be grasped. Based on the color of the spot formed by the collimated light, it is possible to identify which light source formed the spot, and based on the positional relationship and the distance between the spots, information regarding the distance from the robot hand to the object to be grasped can be obtained.

Furthermore, a technology for grasping the posture of a grasped object is disclosed, for example, in Patent Document 2. In this technology, a three-dimensional image capturing device is used to capture a three-dimensional image of the grasped object, a three-dimensional point cloud corresponding to the grasped object is obtained based on this three-dimensional image, and the posture of the grasped object is calculated based on this three-dimensional point cloud.

JP 2005-297100 A JP 2021-016910 A

The technology in Patent Document 1 can obtain information about distance, but has the problem of not being able to obtain information about the posture of the object to be grasped.

In addition, the technology in Patent Document 2 uses a three-dimensional image capture device to capture three-dimensional images, which poses the problem of the device being expensive.

The present invention was made in consideration of the above problems, and aims to provide a light-projecting device that is inexpensive and can display information about the distance from a robot hand to an object to be grasped, and information about the posture of the object to be grasped as viewed from the robot hand.

To solve the above problem, the light-projecting device of the present invention has a first light-projecting means fixed at a first position relative to a robot hand attached to a robot arm, and a second light-projecting means fixed at a second position different from the first position relative to the robot hand, the first light-projecting means emitting a first light beam that forms an image of a first predetermined figure on the surface of an object to be grasped by the robot hand, and the second light-projecting means emitting a second light beam in a direction different from the direction of the first light beam that forms an image of a second predetermined figure on the surface of the object to be grasped by the robot hand.

The light projection method of the present invention includes emitting a first light beam from a first light projection means fixed at a first position relative to a robot hand attached to a robot arm, the first light beam forming an image of a first predetermined figure on the surface of an object to be grasped by the robot hand, and emitting a second light beam from a second light projection means fixed at a second position different from the first position relative to the robot hand, in a direction different from the first light beam, the second light beam forming an image of a second predetermined figure on the surface of an object to be grasped by the robot hand.

In addition, the robot hand system of the present invention includes the above-mentioned floodlight device, a camera that captures an image including an image of the first specified figure and an image of the second specified figure, a display that displays the image captured by the camera, a robot that drives the robot hand, a robot driving unit that drives the robot, and a robot operating unit that operates the robot driving unit.

The effect of the present invention is to provide a light-projecting device that is inexpensive and can provide information about the distance from the robot hand to the object to be grasped and information about the posture of the object to be grasped as seen by the robot hand.

1 is a schematic side view showing a configuration of a floodlight device according to a first embodiment. 2 is a schematic side view showing a first operating state of the floodlight device of the first embodiment. FIG. 4 is a schematic side view showing a second operating state of the floodlight device of the first embodiment. FIG. 11 is a schematic side view showing a third operating state of the floodlight device of the first embodiment. FIG. FIG. 11 is a schematic side view showing the configuration of a floodlight device according to a second embodiment. FIG. 11 is a schematic side view showing a first operating state of the floodlight device of the second embodiment. FIG. 11 is a schematic side view showing a second operating state of the floodlight device of the second embodiment. FIG. 13 is a block diagram showing a robot hand system according to a third embodiment. FIG. 13 is a block diagram showing a robot hand system according to a fourth embodiment. 13 is a flowchart showing the operation of the robot hand system according to the fourth embodiment.

Below, an embodiment of the present invention will be described in detail with reference to the drawings. However, the embodiment described below has limitations that are technically preferable for implementing the present invention, but does not limit the scope of the invention to the following. Note that similar components in each drawing are given the same numbers, and descriptions may be omitted.

(First embodiment)
1 is a schematic side view showing the configuration of a light-projecting device 10 according to the present embodiment. The light-projecting device 10 has a robot hand 1, a first light-projecting means 2, and a second light-projecting means 3.

The robot hand 1 is attached to the robot arm and grasps the object to be grasped 20.

The first light projecting means 2 is fixed at a first position relative to the robot hand 1. The first light projecting means 2 emits a first light beam 2a that forms an image of a first predetermined figure on the surface of the grasped object 20.

The second light projecting means 3 emits a second light beam 3a in a direction different from the first light beam 2a, which forms an image of a second predetermined figure on the surface of the grasped object 20.

Figure 2(a) is a schematic side view showing the first operating state of the light projector 10. Figure 2(b) is a plan view showing the image 2b of the first predetermined figure and the image 3b of the second predetermined figure on the surface of the object to be grasped 20 in this state. In the example of Figure 2, the direction of the second light ray 3a is set to a direction that has an intersection with the first light ray 2a. However, this direction is just one example, and the second light ray 3a can be in any direction as long as it can form the image 3b of the second predetermined figure on the object to be grasped 20 and is different from the direction of the first light ray 2a. It is also not necessary to have an intersection.

In the example of FIG. 2, the first light projecting means 2 emits a first light beam 2a that forms an image of a substantially circular first predetermined figure, and the second light projecting means 3 emits a second light beam 3a that forms an image of a substantially circular second predetermined figure. Here, the state in FIG. 2 in which the robot hand 1 and the object to be grasped 20 face each other is assumed to have been created in advance by a method different from that of this embodiment. In this embodiment, the state of FIG. 2 is used as a reference state that serves as a reference for comparison with other states. Although not shown, the first light beam 2a and the second light beam 3a are made to have different colors, so that the image of the first predetermined figure 2b and the image of the second predetermined figure 3b can be distinguished. In addition, as will be described later, the image formed by which light beam can also be distinguished by making the image of the first predetermined figure 2b and the image of the second predetermined figure 3b have different shapes. In this embodiment, the emission directions of the first light beam 2a and the second light beam 3a are determined, and the emission directions are made to intersect. Therefore, it is possible to present information for inferring the distance between the robot hand 1 and the object to be grasped 20 from the positional relationship between the image 2b of the first predetermined figure and the image 3b of the second predetermined figure, and the distance between them.

For example, as shown in FIG. 2, if the shapes of the image 2b of the first predetermined figure and the image 3b of the second predetermined figure when the robot hand 1 and the surface of the grasped object 20 are facing each other are taken as their respective reference shapes, the figures will be distorted when the grasped object 20 is tilted. From the changes in these images, information that is useful for inferring the tilt of the grasped object 20 can be presented.

Figure 3(a) is a schematic side view showing the second operating state of the light projecting device 10. Figure 3(b) is a plan view showing the image 2b of the first predetermined figure and the image 3b of the second predetermined figure on the surface of the grasped object 20 in this state.

In the example of FIG. 3, the surface of the object to be grasped 20 is tilted with respect to the line segment connecting the robot hand 1 and the surface of the object to be grasped 20. In this case, the image 2b of the first predetermined figure and the image 3b of the second predetermined figure are distorted from their shapes in the reference state. This distortion of shape indicates that the object to be grasped 20 is in an inclined position relative to the robot hand 1. In other words, as shown in FIG. 3, the light projecting device 10 of this embodiment can present information regarding the position of the surface of the object to be grasped 20 relative to the robot hand 1.

Figure 4(a) is a schematic side view showing the third operating state of the light projecting device 10. Figure 4(b) is a plan view showing the image 2b of the first predetermined figure and the image 3b of the second predetermined figure on the surface of the grasped object 20 in this state.

The image 2b of the first predetermined figure and the image 3b of the second predetermined figure in FIG. 4 are similar to those in FIG. 2. From this, it can be understood that the surface of the grasped object 20 is directly facing the robot hand 1. Furthermore, the image 2b of the first predetermined figure and the image 3b of the second predetermined figure are overlapped. When the state in FIG. 4(b) is observed, the robot hand 1 is directly facing the surface of the grasped object 20, and the robot hand 1 and the surface of the grasped object 20 are at a special distance determined by the arrangement of the first light-projecting means 2 and the second light-projecting means 3. Therefore, for example, this state can be set as the reference state.

As described above, this embodiment can provide a light-projecting device that is inexpensive and can present information about the distance from the robot hand to the object to be grasped and information about the posture of the object to be grasped as seen by the robot hand.

Second Embodiment
5 is a side schematic diagram showing the configuration of a light projecting device 1000 of the second embodiment. The light projecting device 1000 has a robot hand 110, a first light projecting means 120, and a second light projecting means 130. The robot hand 110 is an example of the robot hand 1 of the first embodiment, the first light projecting means 120 is an example of the first light projecting means 2, and the second light projecting means 130 is an example of the second light projecting means 3. The first light projecting means 120 of this embodiment emits a first light beam 121 that forms an image 122 of a first predetermined figure that is substantially circular. The second light projecting means 130 emits a second light beam 131 that forms an image 132 of a second predetermined figure that is cross-shaped. The first light projecting means 120 and the second light projecting means 130 can emit the first light beam 121 and the second light beam 131, for example, by a combination of a light source that emits light radially and a slit. Alternatively, a laser scanning method may be used.

In the example of FIG. 5, the surface of the object to be grasped 200 faces directly toward the robot hand 1. The image of the first predetermined figure 122 and the image of the second predetermined figure 132 are separated by a certain distance.

Figure 6(a) is a schematic side view showing the first operating state of the light projector 1000. Figure 6(b) is a plan view showing the image 122 of the first predetermined figure and the image 132 of the second predetermined figure on the surface of the grasped object 200 in this state.

In the example of FIG. 6, the surface of the object to be grasped 200 is inclined with respect to the line segment connecting the robot hand 110 and the surface of the object to be grasped 200. In this case, the image 122 of the first predetermined figure and the image 132 of the second predetermined figure have shapes distorted from their reference state shapes, as shown in FIG. 6(b). In other words, similar to the first embodiment, it is possible to present information that the surface of the object to be grasped 200 is inclined with respect to the robot hand 110.

Figure 7(a) is a schematic side view showing the second operating state of the light projector 1000. Figure 7(b) is a plan view showing the image 122 of the first predetermined figure and the image 132 of the second predetermined figure on the surface of the grasped object 200 in this state.

In the example of Figure 7, the surface of the object to be grasped 200 faces the robot hand 110. Furthermore, the image 122 of the first predetermined figure and the image 132 of the second predetermined figure overlap. When the state of Figure 7(b) is observed, the robot hand 110 faces the surface of the object to be grasped 200, and the robot hand 110 and the surface of the object to be grasped 200 are at a special distance determined by the arrangement of the first light-projecting means 120 and the second light-projecting means 130. Therefore, for example, this state can be set as the reference state.

In the above explanation, an example was used in which the image of the first predetermined figure and the image of the second predetermined figure were a circle and a crosshair, but these images are not limited to the above example and any predetermined shape can be used.

As described above, according to this embodiment, like the first embodiment, it is possible to provide a light-projecting device that can provide information about the distance from the robot hand to the object to be grasped and information about the posture of the object to be grasped as seen by the robot hand, with an inexpensive configuration.

In the above explanation, two light projecting means are used, but three or more may be used.

Third Embodiment
In this embodiment, a robot hand system using the first or second light projecting device will be described. Fig. 8 is a block diagram showing an example of this robot hand system.

The robot hand system 10000 includes the robot hand 1000 of the second embodiment, a display 2000, a robot 3000, a robot driving unit 4000, and a robot operation unit 5000. The robot hand 1000 is also provided with a camera 1400 that captures an image including an image of a first predetermined figure and an image of a second predetermined figure. The display 2000 displays the image captured by the camera 1400. The robot 3000 includes a multi-joint arm 3100, and the robot hand 1000 is fixed to the tip of the arm 3100. The robot driving unit 4000 drives the robot 3000, the arm 3100, and the robot hand 1000 according to a control signal output from the robot operation unit 5000. The robot operation unit 5000 includes a human interface and receives robot operation input from an operator.

The robot hand system 10000 of this embodiment is controlled by the operation of an operator. The display 2000 and the robot operation unit 5000 are, for example, located at a location away from the robot 3000. The operator can obtain information about the inclination and distance between the robot hand 1000 and the object to be grasped 200 from the image on the display 2000. Then, based on that image, the operator operates the robot operation unit 5000 to adjust the angle of the robot hand 1000 to make it easy to grasp the object to be grasped 2000. Furthermore, by having the robot hand 1000 perform a grasping operation at that angle, the object to be grasped 200 can be easily grasped.

As described above, the robot hand system of this embodiment allows the angle of the robot hand relative to the object to be grasped to be remotely controlled, allowing the robot hand to perform a smooth grasping operation.

(Fourth embodiment)
In the third embodiment, a robot hand system in which the robot hand 1000 and the robot 3000 are operated by an operator has been described, but it is also possible to construct a robot hand system that performs this operation automatically.

Figure 9 is a block diagram showing a robot hand system 11000 that automatically operates a robot. The robot hand system 11000 includes a robot automatic control unit 6000 instead of the robot operation unit 5000 of the robot hand system 10000 of the third embodiment. Although not shown, a robot operation unit 5000 similar to that of the third embodiment may also be included. The other configurations are the same as those of the third embodiment.

In this embodiment, the robot hand system 11000 automatically adjusts the angle of the robot hand 1000 relative to the object to be grasped 200.

Figure 10 is a flowchart showing an example of the operation of the robot hand system 11000. First, a reference state of the angle of the robot hand 1000 with respect to the object to be grasped 200 is created in advance by a method different from that of this embodiment. The method of determining the reference state is arbitrary, but for example, as in the first embodiment, the robot hand 1000 and the object to be grasped 200 can be set to a state in which they face each other directly and the distance between them is a predetermined reference value. Then, the image of the first predetermined figure and the image of the second predetermined figure at that time are stored as templates (S1). Next, the image of the first predetermined figure and the image of the second predetermined figure on the surface of the object to be grasped 200 to be grasped are monitored (S2). Next, the image on the monitor is compared with the template, and the angle of the robot hand is adjusted so that the monitor image approaches the template (S3). This adjustment can be performed using any known technique, but for example, it can be performed by repeatedly fine-tuning the angle so that the difference between the shape of the monitor image and the template becomes small.

As described above, according to this embodiment, the angle of the robot hand can be automatically adjusted to an angle that makes it easy to grasp the object to be grasped.

The present invention has been described above using the above-mentioned embodiment as an exemplary example. However, the present invention is not limited to the above-mentioned embodiment. In other words, the present invention can be applied in various aspects that can be understood by a person skilled in the art within the scope of the present invention.

Reference Signs List 1, 110 Robot hand 2, 120 First light projecting means 3, 130 Second light projecting means 10, 1000 Light projecting device 20, 200 Grasp target object 1400 Camera 2000 Display 3000 Robot 3100 Arm 4000 Robot driving section 5000 Robot operation section 6000 Robot automatic control section 10000, 11000 Robot hand system

Claims (6)

a first light-projecting means fixed to a first position relative to a robot hand attached to a robot arm, and a second light-projecting means fixed to a second position different from the first position relative to the robot hand,
the first light projecting means emits a first light beam that forms an image of a first predetermined figure on a surface of an object to be grasped by the robot hand;
the second light projecting means emits a second light beam in a direction different from that of the first light beam, the second light beam forming an image of a second predetermined figure on a surface of an object to be grasped by the robot hand;
A floodlight device;
a camera that captures an image including an image of the first predetermined figure and an image of the second predetermined figure;
a display for displaying the image captured by the camera;
a robot that drives the robot hand; a robot driving unit that drives the robot; and a robot automatic control unit that automatically controls the robot driving unit based on the image.
having
the robot automatic control unit, in the automatic control, compares the image with a template including an image of the first predetermined figure and an image of the second predetermined figure in a reference state, and repeatedly adjusts the angle of the robot hand so that a difference between a shape of the image and the template becomes small.
Robotic hand system. The first light beam and the second light beam are different colors.
The robot hand system according to claim 1 . The first predetermined figure and the second predetermined figure have different shapes.
The robot hand system according to claim 1 or 2. At least one of the first light projecting means and the second light projecting means,
A combination of a light source that emits light radially and a slit is included.
The robot hand system according to any one of claims 1 to 3. At least one of the first light projecting means and the second light projecting means,
A combination of a laser and a laser scanning means for scanning the laser.
The robot hand system according to any one of claims 1 to 4. A robot operation unit that operates the robot driving unit
The robot hand system according to claim 1 , further comprising:

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