Robot Hand and Vine Crop Harvesting Device Equipped with the Robot Hand

Abstract

To provide a robot hand capable of certainly holding up work objects to transport and reducing the pressure application on the work objects, and a vine crop harvesting device equipped with the hand.SOLUTION: A robot hand is equipped with a plurality of link mechanisms supported by an arm mechanism, and a plurality of finger tip members that are respectively coupled to the plurality of link mechanisms to hold up work objects. Each link mechanism is equipped with a first link member that is fixed to a tip end portion of the arm mechanism at one end and is inserted by a first rotary shaft at the other end, and second, third, and fourth link members. Each finger tip member is journaled to a second rotary shaft of each of the plurality of link mechanisms at a generally center portion and is formed to gradually decrease thickness toward a tip end, and is configured to be inserted by a fourth rotary shaft of each of the plurality of link mechanisms at a rear end. If a base end portion of the third link member is operated, each finger tip member is rotated through the fourth link member and the second link member is rotated about the first rotary shaft.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a robot hand for performing a harvesting operation of vine crops such as pumpkins, watermelons, and melons, and a vine crop harvesting apparatus equipped with this robot hand.

Background Art

[0002] Among conventional harvesting machines for vine crops such as pumpkins, there are some that crush the fruits of vine crops and harvest only the seeds, but there are none for harvesting fresh fruits. Therefore, the harvesting operation of vine crops sold as fresh fruits has to be carried out manually, and mechanization has not advanced.

[0003] For this reason, when harvesting heavy crops such as pumpkins, it is necessary for humans to lift each pumpkin scattered in the field one by one from the ground and collect them, which imposes a physical burden on the harvesting workers.

[0004] Therefore, in order to promote mechanization and improve work efficiency, a harvesting robot has been proposed that can perform individual harvesting of vine crops (for example, heavy crops such as pumpkins) without impairing the value as fresh fruits (Non-Patent Document 1). The harvesting robot described in this Non-Patent Document 1 is equipped with a dedicated hand that can grasp the fruit without damaging it.

[0005] In addition, a watermelon harvesting apparatus for harvesting heavy fruit vegetables such as watermelons has been proposed (Patent Document 1). The watermelon harvesting apparatus described in this Patent Document 1 is attached to the tip of a manipulator that can freely move within a certain range in a three-dimensional space, and has a plurality of suction pads that adsorb and hold the surface of the watermelon. Each suction pad is attached to a frame via an elastic body and is independently provided with a vacuum source.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Non-Patent Document

[0007]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] However, the harvesting robot described in Non-Patent Document 1 has problems such as the possibility that its operation may stop without being able to break the vine when grasping the vine together with the target fruit, and the high possibility of dropping the fruit due to the tensile force from the vine because the fruit is hard, heavy, and spherical.

[0009] In addition, when performing the harvesting work of vine crops, it is difficult to completely remove the vines of the plants growing thickly in the field. Therefore, in order to proceed with the harvesting work, it was essential to take measures against the vines.

[0010] Further, the watermelon harvesting device described in Patent Document 1 has a problem of high cost because a vacuum source for each suction pad is required. In addition, when there are irregularities on the surface of vine crops such as pumpkins, air leakage occurs between the suction pad and the skin, and there is also a problem that reliable suction by the suction pad cannot be achieved.

[0011] Therefore, an object of the present invention is to provide a robot hand that can surely pick up and convey a work object and can reduce the pressure load applied to the work object, and a vine crop harvesting device equipped with this robot hand.

[0012] Another object of the present invention is to provide a robot hand capable of removing the vines of vine crops and avoiding rework due to the vines, and a vine crop harvesting apparatus equipped with this robot hand.

Means for Solving the Problems

[0013] According to the present invention, there is provided a robot hand including a plurality of link mechanisms supported by an arm mechanism, and a plurality of fingertip members respectively connected to the plurality of link mechanisms for lifting an object to be worked on. Each of the plurality of link mechanisms includes a first link member having one end fixed to the tip of the arm mechanism and a first rotation shaft inserted into the other end, a second link member having one end pivotally attached to the first rotation shaft and a second rotation shaft inserted into the other end, a third link member having a substantially central portion pivotally attached to the first rotation shaft, a base end portion connected to a drive mechanism, and a third rotation shaft inserted into the tip portion, and a fourth link member having one end pivotally attached to the third rotation shaft and an insertion hole through which a fourth rotation shaft is inserted into the other end. Each of the plurality of fingertip members has a substantially central portion pivotally attached to the second rotation shaft of each of the plurality of link mechanisms, is formed such that the thickness gradually decreases toward the tip, and is configured such that the fourth rotation shaft of each of the plurality of link mechanisms is inserted into the rear end. When the base end portion of the third link member is operated by a drive mechanism, each of the plurality of fingertip members is rotated via the fourth link member, and the second link member is configured to rotate about the first rotation shaft.

[0014] In this way, the robot hand includes a plurality of link mechanisms and a plurality of fingertip members respectively connected to the plurality of link mechanisms for lifting an object to be worked on. Each link mechanism is a four-bar link mechanism composed of four link members connected to each fingertip member. When the base end portion of the third link member is operated by a drive mechanism, the fingertip member is rotated via the fourth link member, and the second link member is configured to rotate about the first rotation shaft. Thereby, an object to be worked on (for example, a fruit such as a pumpkin) can be reliably lifted from the ground or the like and transported, and the pressure load applied to the object to be worked on can be reduced.

[0015] Each of the plurality of fingertip members is composed of a base end portion and a tip end portion. The base end portion and the tip end portion are connected by a second rotation axis so as to be rotatable within a predetermined range so as to form a substantially "C" shape, and a first elastic body that biases the tip end portion in a direction to open with respect to the second rotation axis is preferably attached. As a result, the "C" shape formed by the base end portion and the tip end portion can only move in the closing direction (upper direction) as a free angle. Therefore, when feeding the fingertip (the tip end portion of the fingertip member) to the bottom of the work object, it is possible to prevent the work object from being dropped when the plurality of link mechanisms are fully closed while accommodating the unevenness of the ground.

[0016] The insertion hole at the other end of the fourth link member is an arc-shaped long hole through which the fourth rotation axis can slide. It is preferable that a second elastic body that biases the fourth rotation axis along the arc-shaped long hole toward this other end portion is provided at the other end of the fourth link member. As a result, when the fingertip (the tip end portion of the fingertip member) is caught by a vine and receives a strong force, only the fingertip can be rotated downward, and the vine can be removed. Therefore, it is possible to avoid redoing the work due to the vine being caught by the robot hand. Further, after removing the caught vine, the fingertip (the tip end portion of the fingertip member) can be reset by the second elastic body.

[0017] The tip end portion of the fingertip member is formed so that the thickness gradually decreases toward the tip end, and a roller having a horizontal rotation axis is provided at the tip end portion. It is preferable that the outer peripheral surface of this roller is configured to be exposed from the surface of the tip end portion. As a result, the fingertip (the tip end portion of the fingertip member) can smoothly enter the bottom of the work object.

[0018] It is preferable that a surrounding member for surrounding the work object is provided on the second link member. As a result, it is possible to prevent the work object from falling between the link mechanisms.

[0019] According to the present invention, the vine crop harvesting device includes the robot hand of the present invention described above, a drive mechanism for driving this robot hand, and an arm mechanism for freely moving the robot hand and the drive mechanism within a predetermined range in three-dimensional space. Thereby, when performing the harvesting operation of vine crops such as pumpkins, watermelons, and melons, the work object can be surely lifted from the ground or the like and conveyed, and the pressure load applied to the work object can be reduced. In addition, the vines of the vine crops can be removed, and rework due to vine entanglement can be avoided.

Effect of the Invention

[0020] According to the present invention, when the vine crop harvesting device equipped with a robot hand performs the harvesting operation of vine crops such as pumpkins, watermelons, and melons, even if the fingertips of the robot hand catch the work object (fruit) and the vines together, it can automatically remove the caught vines. The work object can be surely lifted from the ground or the like and conveyed, and the pressure load applied to the work object can be reduced. In addition, since the vines of the vine crops can be removed, rework due to vine entanglement can be avoided. Furthermore, the fingertips of the robot hand ensure flexibility and can suppress the contact resistance with the uneven ground.

Brief Explanation of Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0022] Hereinafter, embodiments of the robot hand according to the present invention and a vine crop harvesting device equipped with this robot hand will be described with reference to the drawings.

[0023] FIG. 1 schematically shows a vine crop harvesting device 1000 equipped with a robot hand 100 according to an embodiment of the present invention, and FIG. 2 shows the configuration of a link mechanism 100a of the robot hand 100 in FIG. 1. FIG. 3 shows the operating state of the link mechanism 100a of the robot hand 100. In the figure, (A) is the open state of the link mechanism 100a, and (B) is the closed state of the link mechanism 100a. FIG. 4 shows the fingertip member 50 and the first elastic body 60 attached to the second rotation axis S2, and FIG. 5 shows the operating state of the second elastic body 70 provided at the other end of the fourth link member 40 of the link mechanism 100a. Note that FIGS. 2 to 5 show a state in which the surrounding member 80 surrounding the work object P provided on the second link member 20 is omitted.

[0024] As shown in Fig. 1, the vine crop harvesting device 1000 includes a robot hand 100 that lifts the work object P from the ground or the like, a drive mechanism 200 for driving the robot hand 100, and an arm mechanism 300 that freely moves the robot hand 100 and the drive mechanism 200 within a predetermined range in three-dimensional space. The robot hand 100 includes a plurality of link mechanisms 100a and a plurality of fingertip members 50 that are respectively connected to the plurality of link mechanisms 100a and lift the work object P from the ground or the like. In the present embodiment, a plurality of link mechanisms 100a and a plurality of fingertip members 50 (see Fig. 2) are arranged at 90-degree intervals on a circumference separated by a predetermined distance from the central axis C of the drive mechanism 200.

[0025] As shown in Figs. 1 to 5, the link mechanism 100a and the fingertip member 50 include a first link member 10 having one end fixed to the tip of the arm mechanism 300, a second link member 20 rotatably connected to the other end of the first link member 10, a third link member 30 having a base end connected to the drive mechanism 200, a fourth link member 40 having one end rotatably connected to the tip of the third link member 30 and having an insertion hole 41 at the other end, a fingertip member 50 composed of a base end portion 50a and a tip end portion 50b, a first elastic body 60 mounted on the second rotation axis S2, a second elastic body 70 provided at the other end of the fourth link member 40, a surrounding member 80 that surrounds the work object P provided on the second link member 20, a first rotation axis S1 inserted into the other end of the first link member 10, a second rotation axis S2 inserted into the other end of the second link member 20, a third rotation axis S3 inserted into the tip of the third link member 30, and a fourth rotation axis S4 inserted into the rear end of the base end portion 50a of the fingertip member 50.

[0026] One end of the first link member 10 is fixed to the drive mechanism 200 provided at the tip of the arm mechanism 300, the first rotation axis S1 is inserted into the other end, and the first rotation axis S1 is connected to one end of the second link member 20 and is also connected to the central portion of the third link member 30.

[0027] One end of the second link member 20 is pivotally attached to the first rotation axis S1, and a second rotation axis S2 parallel to the first rotation axis S1 is inserted at the other end. One end of this second link member 20 is rotatably connected to the first link member 10, and the other end is connected to the fingertip member 50. Note that the second rotation axis S2 being parallel to the first rotation axis S1 is not a limitation.

[0028] The third link member 30 has its substantially central portion pivotally attached to the first rotation axis S1, its base end portion connected to the drive mechanism 200 via the connection axis S0, and a third rotation axis S3 parallel to the first rotation axis S1 is inserted at the tip end portion. One end of the fourth link member 40 is movably connected to the tip end portion of this third link member 30 via the third rotation axis S3. Note that the third rotation axis S3 being parallel to the first rotation axis S1 is not a limitation.

[0029] One end of the fourth link member 40 is pivotally attached to the third rotation axis S3, and the other end has an insertion hole 41 through which a fourth rotation axis S4 parallel to the first rotation axis S1 is inserted. This insertion hole 41 is an arc-shaped long hole in which the fourth rotation axis S4 can slide. The other end of this fourth link member 40 is connected to the rear end of the base end portion 50a of the fingertip member 50 via the fourth rotation axis S4. Also, an elastic body storage portion 42 for storing the second elastic body 70 is provided at the other end of the fourth link member 40. Note that the fourth rotation axis S4 being parallel to the first rotation axis S1 is not a limitation.

[0030] The fingertip member 50 is composed of a base end portion 50a and a tip end portion 50b. The front end of the base end portion 50a and the rear end of the tip end portion 50b are rotatably connected by a second rotation axis S2, and the base end portion 50a has rotation restricting portions 52 and 53 for restricting the rotation of the tip end portion 50b within a predetermined range. Further, the tip end portion 50b is urged by a first elastic body 60 attached to the second rotation axis S2 to rotate in the opening direction. Thereby, the base end portion 50a and the tip end portion 50b are configured to form a substantially "J" shape. Further, a fourth rotation axis S4 is inserted into the rear end of the base end portion 50a, the tip end portion 50b is formed so that the thickness gradually decreases toward the tip, and a roller 51 having a horizontal rotation axis S5 is provided on the tip end portion 50b. The outer peripheral surface of this roller 51 is configured to be exposed from the surface (upper surface and lower surface) of the tip end portion 50b.

[0031] The first elastic body 60 is, for example, a torsion spring. As shown in FIG. 4, this first elastic body 60 is attached to the second rotation axis S2 and is configured to urge the tip end portion 50a of the fingertip member 50 to rotate in the opening direction. With this configuration, the tip end portion 50b of the fingertip member 50 can rotate only by a predetermined angle (rotation range in FIG. 4) in the closing direction (upper direction), and when feeding the tip end portion 50b of the fingertip member 50 to the bottom of the work object P, it is possible to cope with the unevenness of the ground and prevent the work object P from being dropped when the plurality of link mechanisms 100a are fully closed.

[0032] The second elastic body 70 is, for example, a compression coil spring. This second elastic body 70 is provided in the elastic body housing portion 42 of the fourth link member 40 and is configured to urge the fourth rotation axis S4 along an arc-shaped long hole (insertion hole 41) toward the other end of the fourth link member 40. With this configuration, when the fingertip (tip end portion 50b of the fingertip member 50) of the robot hand 100 is caught by a vine and receives a strong force, only the fingertip can be moved downward to remove the catch of the vine (see FIG. 5). Therefore, it is possible to reduce the rework of the work due to the vine catch of the robot hand 100. Further, after removing the caught vine, the second elastic body 70 can reset the fingertip (tip end portion 50b of the fingertip member 50).

[0033] The surrounding member 80 is formed in a ring shape and is provided inside the second link member 20. By providing this surrounding member 80, when lifting the work object P, it is possible to prevent the work object P from falling between the plurality of link mechanisms 100a and the fingertip member 50.

[0034] The vine crop harvesting device 1000 of the present invention described above can be mounted on a vehicle such as a tractor to perform harvesting work while moving.

[0035] Next, with reference to FIGS. 6 to 8, the operation of the vine crop harvesting device 1000 equipped with the robot hand 100 of the present invention will be described.

[0036] As shown in FIGS. 6 to 8, when harvesting a pumpkin or the like using the vine crop harvesting device 1000, first, the arm mechanism 300 moves the robot hand 100 above the work object P (see FIG. 6(A)). In this case, the plurality of link mechanisms 100a and the fingertip member 50 of the robot hand 100 are in an expanded state. Next, the robot hand 100 is lowered from above the work object P, the tip portion 50b of the fingertip member 50 is brought into contact with the ground, and the tip portion 50b alone is rotated in a closing direction (upper direction) so as to be substantially parallel to the ground (see FIG. 6(B)). Next, when the movable part 200a of the drive mechanism moves upward with respect to the fixed part 200b of the drive mechanism, the plurality of link mechanisms 100a and the fingertip member 50 of the robot hand 100 start to contract in the direction of the central axis C (central part) (see FIG. 7(A)). Next, the plurality of link mechanisms 100a and the fingertip member 50 are contracted in the direction of the central axis C (central part) so that the fingertips (tip portions 50b of the fingertip member 50) move to the lower part of the work object P (see FIG. 7(B)). Next, the plurality of fingertips (tip portions 50b of the fingertip member 50) are inserted between the lower part of the work object P and the ground (see FIG. 8(A)). Then, the arm mechanism 300 raises the robot hand 100 to lift the work object P (see FIG. 8(B)). In this way, individual harvesting of vine crops (for example, heavy crops such as pumpkins) is performed.

[0037] The experimental results of harvesting pumpkins using the vine crop harvesting device 1000 equipped with the robot hand 100 of the present invention will be described below. Table 1 shows the dimensions, shapes, etc. of the pumpkins used in the experiment.

[0038] [Table 1]

[0039] When one vine is caught by the robot hand 100, the experimental results of pumpkin harvesting are shown in Table 2. As shown in Table 2, when one vine is caught, the success probability of lifting is 90%. [Table 2]

[0040] When multiple vines are caught by the robot hand 100, the experimental results of pumpkin harvesting are shown in Table 3. As shown in Table 3, when multiple vines are caught, the success probability of lifting is 85%. [Table 3]

[0041] As described in detail above, according to the present embodiment, the vine crop harvesting device 1000 includes a robot hand 100 for lifting the work object P, a drive mechanism 200 for driving the robot hand 100, and an arm mechanism 300 for freely moving the robot hand 100 and the drive mechanism 200 within a predetermined range in three-dimensional space. The robot hand 100 includes a plurality of link mechanisms 100a for lifting the work object P from the ground or the like and a plurality of fingertip members 50.

[0042] The link mechanism 100a includes a first link member 10 having one end fixed to the drive mechanism movable part 200a at the tip of the arm mechanism 300, a second link member 20 rotatably connected to the other end of the first link member 10, a third link member 30 having a base end connected to the drive mechanism movable part 200a, and a fourth link member 40 having one end rotatably connected to the tip of the third link member 30 and having an insertion hole 41 at the other end. The fingertip member 50 is composed of a base end portion 50a and a tip end portion 50b. The link mechanism 100a further includes a first elastic body 60 mounted on the second rotation shaft, a second elastic body 70 provided at the other end of the fourth link member 40, an enclosure member 80 provided on the second link member 20 to surround the work object P, a first rotation shaft S1 inserted into the other end of the first link member 10, a second rotation shaft S2 inserted into the other end of the second link member 20, a third rotation shaft S3 inserted into the tip of the third link member 30, and a fourth rotation shaft S4 inserted into the rear end of the base end portion 50a of the fingertip member 50.

[0043] Thereby, the harvesting work of heavy crops such as pumpkins can be mechanized and labor-saving, and when performing the harvesting work of vine crops such as pumpkins, watermelons, and melons, the work object P can be surely lifted and conveyed from the ground or the like, and the pressure load applied to the work object P can be reduced. In addition, since the vines of the vine crops can be removed, it is possible to avoid reworking due to vine entanglement. Furthermore, the fingertips of the robot hand 100 have flexibility, and the contact resistance with the uneven ground can be suppressed.

[0044] In the above-described embodiment, an example in which the robot hand 100 has four link mechanisms 100a and the fingertip member 50 has been described, but the present invention is not limited to this. For example, three or five or more link mechanisms and fingertip members may be provided, and the four link mechanisms may be inclined in a spiral direction with respect to the central axis C.

[0045] Also, in the above-described embodiment, an example in which the fingertip member 50 is composed of a base end portion 50a and a tip end portion 50b has been described, but the present invention is not limited to this. For example, the fingertip member may be composed of one member.

[0046] Furthermore, in the above-described embodiment, an example in which the robotic hand 100 is a vine crop as the work object P has been described, but the present invention is not limited to this. The present invention can also be applied to work objects other than vine crops.

[0047] Furthermore, in the above-described embodiment, an example in which the second elastic body 70 is provided at the lower end portion of the fourth link member 40 has been described, but the present invention is not limited to this. For example, as shown in FIG. 9, it may be provided at a position higher than the lower end of the fourth link member 40. In this case, it is possible to prevent soil, dust, etc. from entering the elastic body housing portion 42.

[0048] The above-described embodiments illustrate the present invention and do not limit it. The present invention can be implemented in various other modified and changed forms. Therefore, the scope of the present invention is defined only by the scope of the claims and their equivalent scope.

Industrial Applicability

[0049] The robotic hand and vine crop harvesting device of the present invention can be used for the purpose of mechanizing the harvesting work of vine crops such as pumpkins, watermelons, and melons and reducing the labor burden.

Explanation of Reference Numerals

[0050] 10 First link member 20 Second link member 30 Third link member 40, 40A Fourth link member 41 Insertion hole (arc-shaped long hole) 42 Elastic body housing portion 50 Fingertip member 50a Base end portion 50b tip 51 roller 52, 53 rotation restricting parts 60 first elastic body 70 second elastic body 80 surrounding member 100 robot hand 100a link mechanism 200 drive mechanism 200a movable part of drive mechanism 200b fixed part of drive mechanism 300 arm mechanism 1000 vine crop harvesting device C central axis P object to be worked on S0 connecting shaft S1 first rotation axis S2 second rotation axis S3 third rotation axis S4 fourth rotation axis S5 rotation axis

Claims

1. A robot hand comprising a plurality of link mechanisms supported by an arm mechanism and a plurality of fingertip members respectively connected to the plurality of link mechanisms for lifting an object to be worked from the ground, each of the plurality of link mechanisms comprising a first link member having one end fixed to the tip of the arm mechanism and a first rotation shaft inserted through the other end, a second link member having one end pivotally attached to the first rotation shaft and a second rotation shaft inserted through the other end, a third link member having a substantially central portion pivotally attached to the first rotation shaft, a base end portion connected to a movable portion of a drive mechanism, and a third rotation shaft inserted through a tip end portion, and a fourth link member having one end pivotally attached to the third rotation shaft and an insertion hole through which a fourth rotation shaft is inserted through the other end, each of the plurality of fingertip members having a substantially central portion pivotally attached to the second rotation shaft of each of the plurality of link mechanisms, being formed such that the thickness gradually decreases toward the tip, and being configured such that the fourth rotation shaft of each of the plurality of link mechanisms is inserted through a rear end, when the base end portion of the third link member is operated by the movable portion of the drive mechanism, each of the plurality of fingertip members is rotated via the fourth link member, and the second link member is configured to rotate about the first rotation shaft, and the robot hand is characterized in that when the movable portion of the drive mechanism moves upward, the plurality of link mechanisms and the plurality of fingertip members are configured to contract in the direction of the central axis.

2. A robot hand comprising a plurality of link mechanisms supported by an arm mechanism and a plurality of fingertip members respectively connected to the plurality of link mechanisms for lifting an object to be worked, each of the plurality of link mechanisms comprising a first link member having one end fixed to the tip of the arm mechanism and a first rotation shaft inserted through the other end, a second link member having one end pivotally attached to the first rotation shaft and a second rotation shaft inserted through the other end, a third link member having a substantially central portion pivotally attached to the first rotation shaft, a base end portion connected to a movable portion of a drive mechanism, and a third rotation shaft inserted through a tip end portion, and a fourth link member having one end pivotally attached to the third rotation shaft and an insertion hole through which a fourth rotation shaft is inserted through the other end, Each of the plurality of fingertip members has a substantially central portion axially attached to the second rotation axis of each of the plurality of link mechanisms, is formed such that the thickness gradually decreases toward the tip, and is configured such that the fourth rotation axis of each of the plurality of link mechanisms is inserted into the rear end. When the base end portion of the third link member is operated by the movable portion of the drive mechanism, each of the plurality of fingertip members is rotated via the fourth link member, and the second link member is configured to rotate about the first rotation axis. Each of the plurality of fingertip members is composed of a base end portion and a tip end portion. The base end portion and the tip end portion are connected to be rotatable within a predetermined range by the second rotation axis so as to form a substantially "H" shape, and a first elastic body that biases the tip end portion in a direction to open with respect to the second rotation axis is mounted. The robot hand is characterized by this.

3. Each of the plurality of fingertip members is composed of a base end portion and a tip end portion. The base end portion and the tip end portion are connected to be rotatable within a predetermined range by the second rotation axis so as to form a substantially "H" shape, and a first elastic body that biases the tip end portion in a direction to open with respect to the second rotation axis is mounted. The robot hand according to claim 1, characterized by this.

4. The insertion hole at the other end through which the fourth rotation axis of the fourth link member is inserted is an arc-shaped long hole in which the fourth rotation axis is slidable. A second elastic body that biases the fourth rotation axis along the arc-shaped long hole to the side opposite to the third rotation axis is provided at the other end of the fourth link member through which the fourth rotation axis of the fourth link member is inserted. The robot hand according to any one of claims 1 to 3, characterized by this.

5. The tip end portion of the fingertip member is formed such that the thickness gradually decreases toward the tip, and a roller having a horizontal rotation axis is provided at the tip end portion, and the outer peripheral surface of the roller is configured to be exposed from the surface of the tip end portion. The robot hand according to claim 3 or 4, characterized by this.

6. The robot hand according to any one of claims 1 to 5, A drive mechanism for driving the robot hand, A vine crop harvesting device characterized by comprising an arm mechanism that freely moves the robot hand and the drive mechanism within a predetermined range in three-dimensional space.

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