JP7466780B1 - Gripper, gripping device, and attachment for robot hand - Google Patents

Abstract

The gripping device of the disclosed technology is a gripping device that grips an object to be gripped based on the principle of driven kirigami, and is generally sheet-like and roughly (almost) diamond-shaped overall, with a slit or large hole near the center, which makes it easy to impart a deformation tendency to achieve a center fold or a cover fold.

Description

The disclosed technology relates to gripping tools, gripping devices, and attachments for robotic hands.

In the technical field of robot hands that can grasp objects, there are known robots whose grasping parts (hereafter referred to as "gripping tools") have been inspired by origami. For example, there is the "origami hand," a gripping tool made entirely from paper. Because the "origami hand" is made entirely from paper, it is expected to find application in the medical and food industries, where disposable items are assumed to be used for hygienic reasons.

Patent Document 1 discloses a Gripping Device inspired by an origami "flapping bird" and operating on the same principle. Figure 1 is an explanatory diagram showing a flapping bird created with origami. As shown in Figure 1, when the neck and tail parts of the origami "flapping bird" are held with both hands and pulled toward each other, the left and right wings close as if flapping. The Gripping Device in Patent Document 1 is realized by making cuts in a sheet of flexible material, and by pulling two actuating tabs corresponding to the neck and tail parts, the upper and lower jaw parts corresponding to the left and right wings close, making it possible to grip an object.

International Publication No. 2020/237058

The Gripping Device shown in Patent Document 1 has a great concept of being made from a single sheet of flexible material, but it has some practical drawbacks due to its excessive focus on this concept. One of these, as can be seen from FIG. 6B in Patent Document 1, is that the actuation tab cannot be pulled strongly because shear stress is concentrated in the notch when the actuation tab is pulled.

The present disclosure aims to provide a practical gripping tool by improving a gripping device related to conventional technology in order to solve the above problems.

The gripping device according to the disclosed technology is a gripping device that grips an object to be gripped based on the principle of Driven Kirigami, and is generally (almost) diamond-shaped in sheet form overall, has a set of operating tabs and a set of fingertip portions, and has a slit or large hole near the center, which makes it easy to impart a deformation tendency to achieve a center split fold or a cover fold, and the principle of Driven Kirigami is that the force that bends the set of operating tabs so that they approach each other due to the deformation tendency is converted into a gripping force on the fingertip portions.

Because the gripping device of the disclosed technology has the above-mentioned configuration, it is able to pull the operating tab strongly, making it more practical than conventional ones.

FIG. 1 is an explanatory diagram showing a flapping bird made from origami paper. FIG. 2 is an explanatory diagram showing the features of the gripping tool 100 according to the first embodiment. FIG. 3 is a cross-sectional view taken along line AA of FIG. FIG. 4 is an assembly diagram showing attachment and detachment of fingertip portion 150 in gripping tool 100 according to embodiment 1. As shown in FIG. FIG. 5 is an isometric view showing the appearance of the gripping tool 100 according to the first embodiment. FIG. 6 is an isometric view showing the appearance of the gripping device according to the first embodiment. FIG. 7 is an isometric view showing the appearance of a gripping device according to the second embodiment. FIG. 8 is an explanatory diagram showing the mechanism by which the pulling portion 130 is attached to and detached from the arm portion 200. As shown in FIG. FIG. 9 is a diagram of an origami folding process for explaining the principle of the technique according to the third embodiment. FIG. 10 is a top view showing an example of a shape pattern of a gripping tool or an attachment according to the third embodiment. FIG. 11 is an explanatory diagram showing the process of deformation of the gripping tool or attachment according to the third embodiment, which corresponds to an origami folding diagram. FIG. 12 is an explanatory diagram (side view) showing the deformation process when the attachment according to embodiment 3 is gripped by a commercially available robot hand. FIG. 13 is an explanatory diagram (front view) showing the deformation process when the attachment according to embodiment 3 is gripped by a commercially available robot hand. FIG. 14 is an explanatory diagram (viewed from below) showing the deformation process when the attachment according to embodiment 3 is gripped by a commercially available robot hand. FIG. 15 is an explanatory diagram illustrating a method for imparting a deformation habit to the gripping tool or attachment according to the third embodiment. FIG. 16 is an explanatory diagram showing variations in the method of using the gripping tool or attachment according to the third embodiment. FIG. 17 is a photograph showing a state in which a liquid object to be grasped is grasped using the grasping tool or attachment according to embodiment 3. FIG. 18 is a photograph showing the state of gripping an egg yolk using the gripping tool or attachment according to embodiment 3.

Embodiment 1.
Fig. 2 is an explanatory diagram showing the characteristics of the gripping tool 100 according to embodiment 1. As shown in Fig. 2, the gripping tool 100 according to embodiment 1 includes a gripping portion 110, a tendon portion 120, a pulling portion 130, and a socket portion 140. The tendon portion 120 has a thread portion 122 therein.
Fig. 3 is a cross-sectional view taken along line A-A in Fig. 2. As shown in Fig. 3, the gripping part 110 constituting the gripping tool 100 preferably has a two-layer structure consisting of a coating layer 112 and a core layer 114. In addition, as shown in Figs. 2 and 3, the core layer 114 may have a plurality of holes 116 formed therein in order to adjust the rigidity.

Figure 4 is an assembly diagram showing the attachment and detachment of the fingertip portion 150 in the gripping tool 100 according to embodiment 1. The fingertip portion 150 is detachable from the socket portion 140 constituting the gripping tool 100.

Fig. 5 is an isometric view showing the appearance of gripping tool 100 according to embodiment 1. The two solid black arrows in Fig. 5 indicate the directions in which fingertip portion 150 moves as if the fingers are closing when gripping an object, and this is achieved by pulling two pulling portions 130 in the directions of the white arrows. This driving principle is the same as that of the origami "flapping bird" shown in Fig. 1.
Origami flapping birds are not well known overseas. Another example of something based on the same principle is the mechanism in a pop-up picture book. Overseas, the mechanism in a pop-up picture book is sometimes called "kirigami." Kirigami is also recognized overseas as a type of origami. Therefore, in this specification, this driving principle is referred to as the "principle of driven kirigami."

<<Holding portion 110 constituting holding tool 100>>
The gripping portion 110 constituting the gripping tool 100 is a sheet-like component that covers an object to be gripped. Figuratively speaking, the gripping portion 110 is a component that corresponds to the palm and back of a human hand.
As described above, the gripping part 110 constituting the gripping tool 100 is preferably a two-layer structure consisting of a coating layer 112 and a core layer 114. The coating layer 112 may be made of a synthetic resin such as silicone resin. The coating layer 112 may be made of a soft rubber-like material with high friction such as urethane rubber, in addition to silicone resin. The core layer 114 may be made of a synthetic resin such as PET (Polyethylene terephthalate). Such a two-layer structure gripping part 110 can be manufactured by a method of pouring resin into a mold. The core layer 114 may be made of a plastic material produced from plant-derived lactic acid such as PLA resin, in addition to PET. The core layer 114 is used to increase the rigidity that cannot be obtained by the coating layer 112 alone, so a material suitable for increasing the rigidity is selected.
The gripping portion 110 as a whole needs to have the strength and properties to be able to elastically deform without breaking so that the principle of driving kirigami can be exerted.

Tendon portion 120 constituting gripping tool 100
The tendon 120 constituting the gripping tool 100 is a component that transmits the force pulling the gripping part 110 from both sides, and is a component that corresponds to a human tendon in a metaphorical sense. In other words, the gripping device having the gripping tool 100 according to the disclosed technology can be said to be a tendon-driven robot.
The tendons 120 have a default V-shape as shown in FIG. 2, but when tension is applied the angle of the V becomes smaller.
As described above, the tendon portion 120 has a structure including the thread portion 122 therein. The thread portion 122 may be, for example, a synthetic fiber such as a high-density polyethylene fiber or a chemical fiber. The thread portion 122 may be a nylon fishing line. Furthermore, the thread portion 122 may be a metal wire. The material of the tendon portion 120 that covers the thread portion 122 may be the same as that of the covering layer 112.
The tendon portion 120 as a whole must have the strength and properties to allow the gripping portion 110 to be pulled from both sides without stretching or breaking.

<<Tensioning portion 130 constituting the gripping tool 100>>
The tensioning portion 130 constituting the gripping tool 100 is a component corresponding to the Actuation Tab in Patent Document 1. In terms of function, the tensioning portion 130 constituting the gripping tool 100 is a component that connects the tendon portion 120 and the arm portion 200 described below. As shown in Figures 2 and 5, the tensioning portion 130 functions like a pulley and can pull the thread portion 122. The tensioning portion 130 is provided with an axial hole for attachment and detachment to the arm portion 200.

<<Socket portion 140 constituting the gripping tool 100>>
The socket portion 140 constituting the gripping tool 100 is a component that connects the gripping portion 110 and the fingertip portion 150. The socket portion 140 enables the fingertip portion 150 to be attached to and detached from the gripping portion 110.
Providing the socket portion 140 and making the fingertip portion 150 detachable allows a variety of fingertip portions 150 to be prepared in advance according to the anticipated grasping object, and during operation, a fingertip portion 150 with properties suitable for grasping the object can be selected. Providing the socket portion 140 and making the fingertip portion 150 detachable also has the advantage of facilitating replacement for hygienic reasons and facilitating maintenance.

Fingertip portion 150 constituting gripping tool 100
The fingertip parts 150 constituting the gripping tool 100 are parts that come into direct contact with the object to be gripped, and are metaphorically equivalent to human fingers. However, in Fig. 2 to Fig. 7 which explain the technology disclosed herein, the fingertip parts 150 are not depicted as being independently movable like human fingers.
The fingertip portion 150 may be made of the same material as the gripping portion 110. The fingertip portion 150 may also have the same two-layer structure as the gripping portion 110. However, an advantageous effect of the gripping tool 100 according to the present disclosure is that the fingertip portion 150 is detachable, so that a material and structure suitable for gripping an object to be gripped can be adopted. The conventional Gripping Device shown in Patent Document 1 is limited to the concept of being manufactured from a single sheet of flexible material, and therefore has a practical disadvantage in that the rigidity of the portion corresponding to the fingertip is not necessarily sufficient. The feature of the present disclosure, which includes the socket portion 140 and the fingertip portion 150, is an ingenuity for overcoming this practical disadvantage.
It is important that the fingertip 150 has the rigidity and friction to prevent the object from slipping off when being grasped. It is also important that the fingertip 150 has flexibility so as not to damage the object when being grasped.

As described above, it is conceivable to prepare multiple types of fingertip 150 according to the intended objects to be grasped. This idea is the same as the fact that tweezers are prepared with various tip shapes according to the purpose of use.
For example, if the object to be grasped is a plate-like object such as a board or a card, the fingertip 150 may have a thin tip and a shape that is slightly curved inward in the grasping direction. By designing the fingertip 150 in this way, it is possible to grasp and lift up a plate-like object placed on a table.

Figure 6 is an isometric view showing the appearance of the gripping device according to embodiment 1. As shown in Figure 6, the gripping device according to embodiment 1 includes a gripping tool 100, an arm portion 200-A, and a drive portion 300.

<<Arm 200 constituting the gripping device>>
The arm 200 constituting the gripping device is a component that connects the gripping tool 100 and the drive unit 300. As its name suggests, the arm 200 can be said to be a component that corresponds to a human arm, figuratively speaking. As shown in Fig. 6, when emphasizing that the arm 200 is the aspect in the first embodiment, the reference symbol -A is added to the arm 200, and the arm 200-A is displayed.

The arm portion 200-A has, for example, a shaft-like shape at its lower tip (hereinafter referred to as the “detachable shaft”), and can hold the gripping tool 100 by passing the detachable shaft through an axial hole provided in the tensioning portion 130.
6, when the pulling portion 130 of the arm 200-A is pulled in the direction indicated by the white arrow, the restoring force of the gripping portion 110 pulls the arm 200-A in the opposite direction to the white arrow. The gripping tool 100 is held by a force based on the restoring force of the gripping portion 110. If the arm 200-A is driven in the direction opposite to the white arrow to loosen the thread portion 122, the restoring force of the gripping portion 110 weakens. In other words, the gripping device according to the disclosed technology can easily remove the gripping tool 100 from the arm 200-A by driving the arm 200-A to loosen the tension on the thread portion 122.

Fig. 8 is an explanatory diagram showing the mechanism by which the tensioning part 130 is attached to and detached from the arm part 200. As shown in Fig. 8, a detachment shaft is provided on the arm part 200, and a shaft hole is provided on the tensioning part 130. In order to easily remove the gripping tool 100 from the arm part 200, it is preferable that the diameter of the shaft hole is larger than the diameter of the detachment shaft.
In addition, the arm portion 200 may be provided with a taper or step on the detachment shaft to prevent the detachment shaft from slipping out of the shaft hole when the object to be grasped is heavy.

<<Drive unit 300 constituting the gripping device>>
The driving unit 300 constituting the gripping device is a component that drives the arm unit 200. Specifically, the driving unit 300 may be realized by an electric slider. The electric slider includes a motor and a mechanism that converts rotational motion into linear motion. Since it is sufficient for the driving unit 300 to realize linear motion, a linear motor may be adopted.

The gripping device must control not only the opening and closing of the gripping tool 100, but also the position and posture of the gripping tool 100 required to grip the object to be gripped. Figure 6 shows a drive unit 300 that realizes the opening and closing of the gripping tool 100, but does not show all of the components required for the gripping device. Although not shown in Figure 6, the gripping device has a mechanism and drive source that change the position and posture of the gripping tool 100.

The advantageous effect of the gripping tool 100 of embodiment 1 is that since the gripping tool 100 is equipped with a tendon portion 120 having a thread portion 122 therein and a pulling portion 130 that functions like a pulley, shear stress is not concentrated in the cut portion of the sheet, and the pulling portion 130, which is the operating tab, can be pulled strongly.

Another advantageous effect of the gripping device 100 of embodiment 1 is that by making the fingertip portion 150 detachable, a material and structure suitable for gripping the object to be gripped can be adopted, and the rigidity of the fingertip portion 150 necessary for gripping can be ensured.

The advantageous effect of the gripping device of embodiment 1 is that since the pulling portion 130 is provided with an axial hole for attachment and detachment to the arm portion 200-A, and the arm portion 200-A is provided with a detachment axis, by driving the arm portion 200-A to release the tension on the thread portion 122, the gripping tool 100 can be easily removed from the arm portion 200-A.
Therefore, the gripping device according to the disclosed technique can provide a disposable gripping tool 100 together with the gripped object to be discarded, for example, at a site where contaminated medical waste or radioactive materials are handled, thereby contributing to automation.

As described above, the gripping tool 100 and gripping device of embodiment 1 are more practical than those of the prior art.

Embodiment 2.
The gripping device according to the second embodiment is a modified example of the gripping device according to the disclosed technique.
Unless otherwise specified, the same reference numerals as those used in the first embodiment are used in the second embodiment. Furthermore, in the second embodiment, descriptions that overlap with those in the first embodiment are omitted as appropriate.
When emphasizing that the arm portion 200 is the aspect in the second embodiment, the reference numeral will be followed by -B, and the arm portion will be displayed as "arm portion 200-B."

FIG. 7 is an isometric view showing the appearance of a gripping device according to the second embodiment.
In the gripping device according to the first embodiment shown in Fig. 6, arm 200-A moves in the horizontal direction indicated by the white arrow, thereby causing fingertip 150 to grip. On the other hand, in the gripping device according to the second embodiment shown in Fig. 7, arm 200-B moves in the vertical direction indicated by the white arrow, thereby causing fingertip 150 to grip. The drive direction of arm 200 is converted from the horizontal direction to the vertical direction by two guide rollers 210, as shown in Fig. 7. When viewed from thread portion 122, guide roller 210 functions as a pulley, similar to tension portion 130.

An effect unique to the gripping device of embodiment 2 is that the driving direction of arm 200-B is converted to the vertical direction, thereby making it possible to reduce the area occupied by the device compared to embodiment 1.

Another effect unique to the gripping device of embodiment 2 is that, by providing two guide rollers 210, it is possible to prevent the gripping tool 100 from becoming unstable, in that the gripping tool 100 would rotate around the axis along which it is pulled.

As described above, the gripping device of embodiment 2, like the gripping device of embodiment 1, is more practical than those of the prior art.

Embodiment 3.
The technology according to the third embodiment is a modified example of the technology disclosed herein. In the first and second embodiments, a structure for converting a pulling force into a gripping force is shown, but the technology disclosed herein is not limited thereto. The third embodiment clarifies a structure for converting a gripping force into another gripping force. The technology disclosed herein shown in the third embodiment can be applied to, for example, realizing a commercially available robot hand (arm-type robot) to indirectly grip a gripping target without directly gripping the target. Specifically, the technology disclosed herein shown in the third embodiment can be applied as an attachment for a robot hand.

FIG. 9 is a diagram of origami paper to explain the principle of the technique according to the third embodiment. FIG. 9 is a folding diagram of a gripping tool (or an attachment for a robot hand) created using diamond-shaped origami paper as a whole. SE (from Short-Edge) that appears in FIG. 9 represents an obtuse-angled edge. SE can also be said to be the edge on the side that is closer to the center. LE (from Long-Edge) that appears in FIG. 9 represents an acute-angled edge. LE can also be said to be the edge on the side that is farther from the center.
Figure 9A is a development of a paper model of a gripping tool made using diamond-shaped origami paper. In the development, the valley folds are shown with dashed lines and the mountain folds are shown with dashed lines.
Figure 9B shows the first step in the folding diagram. Specifically, Figure 9B shows how the origami paper has been slightly deformed by the fold lines.
Fig. 9C shows the second step in the folding diagram. Specifically, Fig. 9C shows the shape of the origami when the SE of the origami is lightly held by a human hand.
Figure 9D shows the final step in the folding diagram. In Figure 9D, the origami is gripping the object (a rubber band in this example). As shown in Figure 9D, the origami (final form) realized by this folding method can be said to convert the gripping force of the human hand into another gripping force (the force to grip the object).

The inventors of the disclosed technology have discovered that origami folding methods that convert a gripping force into another gripping force include "middle split fold" or "cover fold". A structure that includes a "middle split fold" or "cover fold" can be said to be an example that embodies the principle of Drive Kirigami. In FIG. 9A, the fold line from the center of the origami toward the LE changes from a mountain fold line to a valley fold line. This type of folding method realizes a "middle split fold". Conversely, a folding method in which the fold line from the center toward the corner changes from a valley fold line to a mountain fold line is a "cover fold".

When the raw material is paper, as in the origami shown in Figure 9, the final shape is realized by making creases in the paper.
However, as described above, the gripping tool or attachment envisioned by the present disclosure is made of synthetic resin such as silicon resin, PET, etc., or plastic material such as PLA resin, etc. It can be said that the present disclosure relates to a structure that realizes the same effect on resin as on paper.

Figure 10 is a top view showing example shape patterns of a gripper or attachment according to embodiment 3. Eight patterns (CA1, CA2, CB1, CB2, CC1, CC2, CD1, CD2) are shown in Figure 10, all of which are generally (almost) diamond-shaped overall, with a slit or large hole near the center. The inventors of the disclosed technology have found that providing a slit or large hole near the center is effective as a structure that achieves the same effect in resin, etc. as creases in paper.

Of the shape patterns shown in Fig. 10, CD1 and CD2 both have a large hole in the center. The length of the large hole, indicated as s, of CD2 is larger than that of CD1. Regardless of the mechanism, the inventors of the disclosed technology have found that CD2, which has a large large hole, generates a larger gripping force than CD1.
The slit or large hole provided near the center of the gripping tool or attachment plays a large role in determining the shape when gripping an object (hereinafter referred to as the "grip shape").

Fig. 11 is an explanatory diagram showing the process of deformation of a gripping tool or attachment according to embodiment 3, which corresponds to an origami folding diagram. More specifically, Fig. 11 explains the process of deformation of a gripping tool or attachment realized in the shape pattern of CD2 shown in Fig. 10 using silicon resin as a raw material.
11A to 11D are stop-motion images of the continuous movements of a human hand as it grasps a gripping tool or attachment in a time series.
FIG. 11D shows that the aforementioned “cover fold” is achieved in which the fold line from the center to the corner changes from a valley fold to a mountain fold.

As mentioned above, in origami, the final shape is realized by making folds along the development diagram. The gripping tool or attachment according to the disclosed technology can also achieve the gripping shape shown in Figs. 11A to 11D by giving it the deformation habit shown in Figs. 11A to 11D, and can function as a gripping tool or attachment. When the raw material is silicone resin, gravity also assists in the deformation to Figs. 11A to 11D by holding the gripping tool or attachment in the orientation shown in Fig. 11. The inventors of the disclosed technology have found that it is sufficient to perform the work of giving it the deformation habit shown in Figs. 11A to 11D just once.

FIG. 12 is an explanatory diagram (side view) showing the deformation process when the attachment according to embodiment 3 is gripped by a commercially available robot hand.
12A to 12D are stop-motion images of the continuous movements of the robot hand as it grasps an attachment in chronological order.
FIG. 12D also shows that the aforementioned “cover fold” in which the fold line from the center to the corner changes from a valley fold to a mountain fold can be achieved.
In FIG. 12, the gripping direction of the robot hand is the direction connecting the front and back of the paper, but the direction in which the object is gripped is the direction connecting the right and left of the paper.

FIG. 13 is an explanatory diagram (front view) showing the deformation process when the attachment according to embodiment 3 is gripped by a commercially available robot hand.
Figures 13A to 13D are stop-motion images of the continuous movement of a robot hand as it grasps an attachment in a time series. In the example of Figure 13, the robot hand grasps the long side of the attachment, i.e., LE, and the short side of the attachment, i.e., SE, grasps the object to be grasped. Also, as shown in Figure 13, the robot hand may change the angle of the hand so as to lift both sides of the attachment (see especially Figure 13D).
From Fig. 13, it can be seen that the large hole provided in the center of the attachment makes it easy to realize "cover folding". The shape of the large hole itself is not limited to a simple circle or ellipse, but should be designed to make it easy to realize "cover folding" (for example, see Fig. 14A described later).

FIG. 14 is an explanatory diagram (viewed from below) showing the deformation process when the attachment according to embodiment 3 is gripped by a commercially available robot hand.
14A to 14D are stop-motion images of the continuous movements of the robot hand as it grasps an attachment in chronological order.
The shape of the large hole shown in Figure 14A has two angular, non-curved portions in the long direction of the attachment. Such a feature makes it easier to "fold over".

FIG. 15 is an explanatory diagram illustrating a method for imparting a deformation habit to the gripping tool or attachment according to the third embodiment.
FIG. 15A shows a case where the gripping tool or attachment is realized with silicon resin, and as described above, the deformation habit in this case can be imparted by human hand only once.
15B shows a gripper or attachment made of plastic material. When made of plastic material, the gripper or attachment is fixed to a cylindrical metal jig and heated to about 80°C for about 1 hour in a thermostatic chamber or the like. By going through this process, the gripper or attachment made of plastic material is given a deformation habit.
Fig. 15C also shows a gripping tool or attachment made of a plastic material. Fig. 15C shows an attachment member having a curved slit. The attachment member having a curved slit can also impart a deformation habit to a gripping tool or attachment made of a plastic material.

FIG. 16 is an explanatory diagram showing variations in the method of using the gripping tool or attachment according to the third embodiment.
16A is an explanatory diagram showing a method of gripping an object with two LEs (the corners farther from the center). When gripping an object with two LEs, the gripping force is weak, but delicate movements can be realized.
16B is an explanatory diagram showing a method of using the device to grasp an object with two SEs (the corners closer to the center). When the object is grasped with two SEs, the grasping force is strong and it is easy to give the object a deformation habit.
16, the gripping tool or attachment according to the disclosed technology can realize a gripping force according to the application by designing the ratio of the distance between LE and SE. It can be said that the ratio of the distance between LE and SE has a property in common with the gear ratio between two gears.

Figure 17 is a photograph showing how a liquid-like object is grasped using a grasping tool or attachment according to embodiment 3. As shown in Figure 17, the shape of the grasping tool or attachment according to the disclosed technology is also suitable for a liquid-like object.

Figure 18 is a photograph showing an egg yolk being grasped using a grasping tool or attachment according to embodiment 3. As shown in Figure 18, the shape of the grasping tool or attachment according to the disclosed technology is suitable for foods that need to be handled delicately, such as egg yolk.

The technical feature unique to the gripping tool or attachment of embodiment 3 is that it is generally sheet-like and rhomboidal in shape, with a slit or large hole near the center.
By having this technical feature, the gripping tool or attachment according to embodiment 3 can easily impart a deformation tendency to achieve a "middle fold" or a "cover fold."
The gripping tool or attachment of embodiment 3 is "center-folded" or "cover-folded," so that the gripping force of a commercially available robot hand can be converted into a different gripping force for gripping the object to be gripped.
As described above, the gripping tool or attachment of embodiment 3 does not require pulling on the actuation tab, and therefore solves the problem of the prior art in which shear stress is concentrated in the notch when the actuation tab is pulled, causing it to break.

(Additional Note)
The claims as originally filed in the application from which this application claims priority are as follows, with semicolons used instead of the comma and line break combinations in the original claims:
[Claim 1]
A gripping device for gripping an object based on the principle of driven Kirigami, comprising: a sheet-like gripping portion which covers the object; a tendon portion which has a thread portion inside and transmits a force pulling the gripping portion from both sides; a pulling portion which is connected to the tendon portion and functions as a pulley; and a fingertip portion which is attached to and detached from the gripping portion via a socket portion; the gripping portion has a two-layer structure consisting of a covering layer and a core layer.
[Claim 2]
The gripping tool according to claim 1, wherein the gripping portion has: the covering layer made of a silicone resin or a urethane rubber; and the core layer made of a plastic material.
[Claim 3]
A gripping device comprising: a gripping tool as described in claim 1; and an arm portion connecting the gripping tool and a drive unit; the drive unit drives the arm portion in a direction in which the gripping tool deforms due to tension and grasps the object to be grasped.
[Claim 4]
The gripping device of claim 3, wherein the arm has a detachment shaft; the tensioning portion has an axial hole having a larger diameter than the detachment shaft; the gripping tool is held on the arm by passing the detachment shaft through the axial hole; and the gripping tool can be removed from the arm by driving the arm with the driving portion to release the tension.
[Claim 5]
The gripping device according to claim 4 , wherein the detachment shaft has a taper or a step.
[Claim 6]
The gripping device according to claim 4 , wherein the gripping tool is disposable together with the gripped object to be discarded.

The gripping tool, gripping device, and attachment for a robot hand according to the disclosed technology can be applied to robotic automation in the medical and food fields, for example, and has industrial applicability.
In particular, the disclosed technology can provide an attachment for a disposable robot hand in sites where contaminated medical waste or radioactive materials are handled, thereby contributing to automation.

100 gripping tool, 110 gripping portion, 112 covering layer, 114 core layer, 116 hole, 120 tendon portion, 122 thread portion, 130 tension portion, 140 socket portion, 150 fingertip portion, 200 (200-A, 200-B) arm portion, 210 guide roller, 300 drive portion.

Claims (5)

A gripping tool that grips a gripping object based on the principle of driven Kirigami,
The overall shape is roughly diamond-shaped,
a pair of actuation tabs and a pair of fingertips;
A slit or a large hole is provided near the center,
The slit or the large hole can easily impart a deformation tendency for realizing a middle fold or a cover fold,
The principle of the driving kirigami is to convert the force of bending the pair of actuation tabs toward each other into a gripping force on the fingertips by the deformation habit.
Grip tool. The material is silicone resin, urethane rubber, or plastic material.
The gripping tool according to claim 1. Disposable together with the grasped object to be discarded;
The gripping tool according to claim 1. The gripping tool according to claim 1 , which is an attachment for a robot hand. The gripping tool according to claim 1 ;
an arm for gripping the actuation tab of the gripper;
and a drive unit that drives the arm portion and deforms the gripping tool by a bending force applied by the arm portion so that the pair of actuation tabs approach each other, thereby gripping the gripping object.
Grip device.

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