JP2022189234A - Robot hand and vine crop harvesting device equipped with robot hand - Google Patents

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

The present invention relates to a robot hand for harvesting climbing crops such as pumpkins, watermelons, and melons, and a climbing crop harvesting apparatus equipped with this robot hand.

Conventional harvesting machines for climbing crops such as pumpkins include those for pulverizing fruits of climbing crops and harvesting only seeds, but not for fruits and vegetables. Therefore, the harvesting of climbing crops sold for fruits and vegetables had to be done manually, and mechanization had not progressed.

For this reason, when harvesting pumpkins, which are heavy crops, for example, it is necessary for humans to pick up the pumpkins scattered in the field one by one from the ground. It was a heavy financial burden.

Therefore, in order to promote mechanization and improve work efficiency, a harvesting robot has been proposed that can individually harvest climbing crops (for example, heavy crops such as squash) without impairing the value of fruits and vegetables. Non-Patent Document 1). The harvesting robot described in Non-Patent Document 1 is equipped with a dedicated hand capable of grasping fruit without damaging it.

Also, a watermelon harvesting apparatus for harvesting heavy fruit vegetables such as watermelons has been proposed (Patent Document 1). The watermelon harvesting device described in Patent Document 1 has a plurality of suction pads attached to the tip of a manipulator that can move freely within a certain range within a three-dimensional space, and that suctions and holds the surface of the watermelon. , each suction pad is mounted on the frame via an elastic member, and is independently provided with a vacuum source.

JP-A-10-70936

“AI, drones, and robots work together to efficiently harvest large pumpkins,” Newswitch, [online], May 29, 2019, Nikkan Kogyo Shimbun, “Searched April 30, 2021” , Internet <URL: https://newswitch.jp/p/17833>

However, when the harvesting robot described in Non-Patent Document 1 grabs the vine together with the target fruit, the operation may stop without tearing off the vine, and the fruit is hard and heavy. Due to the spherical shape, there were problems such as a high possibility of dropping the fruit due to the pulling force from the vine.

In addition, when harvesting climbing crops, it is difficult to completely remove the vines that grow thickly in the field, so it was essential to take measures against the vines in order to proceed with the harvesting work. .

In addition, the watermelon harvesting device described in Patent Document 1 requires a vacuum source for each suction pad, which causes a problem of high cost. In addition, when the surface of climbing crops such as pumpkins is uneven, air leaks from between the suction pad and the epidermis, and there is also the problem that the suction pad cannot reliably suction the crop.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a robot hand capable of reliably picking up and transporting a work object and reducing the pressure load applied to the work object, and a sleek robot hand equipped with the robot hand. To provide a crop harvesting device.

Another object of the present invention is to provide a robot hand capable of unhooking the vines of a climbing crop and avoiding rework due to the vines getting caught, and a climbing crop harvesting apparatus equipped with this robot hand. to do.

According to the present invention, a robot hand is provided that includes a plurality of link mechanisms supported by an arm mechanism, and a plurality of fingertip members that are respectively connected to the plurality of link mechanisms and hold up a work object. Each of the plurality of link mechanisms includes a first link member having one end fixed to the distal end of the arm mechanism and having the other end inserted with the first rotation shaft, and one end connected to the first rotation shaft. a second link member having a second pivot shaft inserted into the other end; a substantially central portion pivotally attached to the first pivot shaft; a base end connected to a drive mechanism; a third link member into which a third rotating shaft is inserted; one end of which is pivotally attached to the third rotating shaft; and a fourth link member. 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, and is formed so that the thickness gradually decreases toward the tip, and a plurality of fingertip members are provided at the rear end. It is configured such that each fourth pivot shaft of the link mechanism is inserted. When the base end portion of the third link member is operated by the drive mechanism, each of the plurality of fingertip members is rotated via the fourth link member, and the second link member moves along the first rotation shaft. is configured to rotate around the

As described above, the robot hand includes a plurality of link mechanisms and a plurality of fingertip members that are connected to the plurality of link mechanisms and lift up the work object. Each link mechanism is a four-bar link mechanism composed of four link members connected to each fingertip member, and when the base end of the third link member is operated by the drive mechanism, the fourth link member The second link member is configured to rotate about the first rotation shaft while the fingertip member is rotated via the. As a result, the work object (for example, a fruit such as a pumpkin) can be reliably picked up from the ground and conveyed, and the pressure load applied to the work object can be reduced.

Each of the plurality of fingertip members is composed of a base end portion and a tip end portion, and the base end portion and the tip end portion are rotated within a predetermined range by a second rotation shaft so as to form a substantially "F" shape. It is preferable that a first elastic body, which is movably connected and urged to rotate in a direction to open the distal end portion, is attached to the second rotating shaft. As a result, it is possible to move only in the closing direction (upward direction) with the free angle of the "F" shape consisting of the base end and the tip end, so that the fingertip (fingertip member) The work object can be prevented from being dropped when the plurality of link mechanisms are closed while coping with the unevenness of the ground when feeding the tip part).

The insertion hole at the other end of the fourth link member is an arc-shaped elongated hole in which the fourth rotation shaft can slide. A second elastic body is preferably provided along the hole to bias the other end. As a result, when the fingertip (the tip of the fingertip member) is caught by the temple and receives a strong force, only the fingertip can be rotated downward, so that the temple can be disengaged. Therefore, it is possible to avoid redoing the work due to the robot hand being caught by the vine. In addition, after the hooked temple is removed, the fingertip (tip of the fingertip member) can be repositioned by the second elastic body.

The tip of the fingertip member is formed so that the thickness gradually decreases toward the tip, and the tip is provided with a roller having a horizontal axis of rotation. It is preferably configured to be exposed. As a result, the fingertip (tip of the fingertip member) can smoothly enter the bottom of the work object.

It is preferable that the second link member is provided with an enclosing member that encloses the work object. As a result, the work object can be prevented from falling from between the link mechanisms.

According to the present invention, the climbing crop harvesting apparatus includes the above-described robot hand of the present invention, a drive mechanism for driving the robot hand, and a robot hand and the drive mechanism that can be freely moved within a predetermined range in a three-dimensional space. and an arm mechanism for moving. As a result, when harvesting climbing crops such as pumpkins, watermelons, and melons, the work object can be reliably picked up from the ground and conveyed, and the pressure load applied to the work object can be increased. can be reduced. In addition, it is possible to unhook the vines of climbing crops, thereby avoiding rework due to the vines getting caught.

According to the present invention, a climbing crop harvesting apparatus equipped with a robot hand is designed so that when harvesting climbing crops such as pumpkins, watermelons, and melons, the fingertips of the robot hand touch the work object (fruit). Even if you hook it together, you can automatically remove the hooked vine. The work object can be reliably picked up from the ground or the like and conveyed, and the pressure load applied to the work object can be reduced. In addition, since it is possible to unhook the vines of climbing crops, it is possible to avoid redoing work due to the vines getting caught. Furthermore, the fingertips of the robot hand are flexible enough to reduce contact resistance with uneven ground.

1 is a perspective view schematically showing the configuration of a climbing crop harvesting device equipped with a robot hand according to an embodiment of the present invention; FIG. FIG. 2 is a perspective view schematically showing a configuration example of a link mechanism of the robot hand in FIG. 1; FIG. 2 is a side view showing an open state and a closed state of a link mechanism of the robot hand in FIG. 1; FIG. 2 is a side view showing a rotation range of a distal end portion of a fingertip member of a link mechanism of the robot hand shown in FIG. 1 and a configuration of a first elastic body; 2 shows the operating state of the second elastic body provided at the other end of the fourth link member of the link mechanism of the robot hand in FIG. 1; 1 is a diagram (1) showing an operating state of a climbing crop harvesting apparatus equipped with a robot hand of the present invention; FIG. FIG. 2 is a diagram (part 2) showing the operating state of the climbing crop harvesting device equipped with the robot hand of the present invention; FIG. 3 is a diagram (3) showing the operating state of the climbing crop harvesting device equipped with the robot hand of the present invention; FIG. 11 is a partial cross-sectional view schematically showing another configuration example of the fourth link member;

DETAILED DESCRIPTION OF THE INVENTION Embodiments of a robot hand according to the present invention and a climbing crop harvesting apparatus provided with the robot hand will be described below with reference to the drawings.

FIG. 1 schematically shows a climbing crop harvesting device 1000 equipped with a robot hand 100 according to one embodiment of the present invention, and FIG. 2 shows the configuration of the link mechanism 100a of the robot hand 100 of FIG. . 3A and 3B show the operating state of the link mechanism 100a of the robot hand 100. FIG. 3A shows the open state of the link mechanism 100a, and FIG. 3B shows the closed state of the link mechanism 100a. 4 shows the fingertip member 50 and the first elastic body 60 attached to the second rotation shaft S2, and FIG. 5 shows the second elastic body 60 provided at the other end of the fourth link member 40 of the link mechanism 100a. 2 shows the operating state of the elastic body 70 of FIG. 2 to 5 show a state in which the enclosing member 80 surrounding the work target P provided on the second link member 20 is omitted.

As shown in FIG. 1, a climbing crop harvesting apparatus 1000 includes a robot hand 100 that picks up a work P from the ground or the like, a drive mechanism 200 for driving the robot hand 100, the robot hand 100 and the drive mechanism. and an arm mechanism 300 for freely moving the robot 200 within a predetermined range in a three-dimensional space. The robot hand 100 includes a plurality of link mechanisms 100a, and a plurality of fingertip members 50 that are connected to the plurality of link mechanisms 100a and hold up the work object P from the ground or the like. In this embodiment, a plurality of link mechanisms 100a and a plurality of fingertip members 50 (see FIG. 2) are arranged at intervals of 90 degrees on a circle spaced apart from the central axis C of the drive mechanism 200 by a predetermined distance.

As shown in FIGS. 1 to 5, the link mechanism 100a and the fingertip member 50 are composed of a first link member 10 fixed at one end to the distal end of the arm mechanism 300 and A second link member 20 rotatably connected, a third link member 30 whose proximal end is connected to the drive mechanism 200, and one end of which is rotatable to the distal end of the third link member 30. A fourth link member 40 having an insertion hole 41 at the other end thereof, a fingertip member 50 composed of a proximal end portion 50a and a distal end portion 50b, and a second rotating shaft S2. a second elastic body 70 provided at the other end of the fourth link member 40; 80, 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 rotating shaft S3 inserted at the tip of the third link member 30 and a fourth rotating shaft S4 inserted at the rear end of the base end 50a of the fingertip member 50 are provided. ing.

One end of the first link member 10 is fixed to the drive mechanism 200 provided at the tip of the arm mechanism 300, and the other end is inserted with the first rotation shaft S1. It is connected to one end of the second link member 20 via the rotation shaft S<b>1 and also connected to the central portion of the third link member 30 .

One end of the second link member 20 is pivotally attached to the first rotation shaft S1, and the other end of the second link member 20 is provided with a second rotation shaft S2 parallel to the first rotation shaft S1. The second link member 20 has one end rotatably connected to the first link member 10 and the other end connected to the fingertip member 50 . In addition, it is not limited that the second rotation axis S2 is parallel to the first rotation axis S1.

The third link member 30 has a substantially central portion that is axially attached to the first rotation shaft S1, a base end portion that is connected to the drive mechanism 200 via a connection shaft S0, and a tip portion that is connected to the first rotation shaft S1. A third pivot shaft S3 is inserted parallel to the shaft S1. One end of a fourth link member 40 is movably connected to the tip of the third link member 30 via a third rotation shaft S3. In addition, it is not limited that the 3rd rotation axis S3 is parallel to the 1st rotation axis S1.

One end of the fourth link member 40 is pivotally attached to the third rotation shaft S3, and the other end thereof is an insertion hole 41 through which the fourth rotation shaft S4 parallel to the first rotation shaft S1 is inserted. have The insertion hole 41 is an arcuate slot through which the fourth rotating shaft S4 can slide. The other end of the 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 shaft S4. 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 . In addition, it is not limited that the fourth rotation axis S4 is parallel to the first rotation axis S1.

The fingertip member 50 is composed of a proximal end portion 50a and a distal end portion 50b. The front end of the proximal end portion 50a and the rear end of the distal end portion 50b are rotatably connected by a second rotating shaft S2, and the proximal end portion 50a regulates the rotation of the distal end portion 50b within a predetermined range. It has rotation restricting portions 52 and 53 . Further, the tip portion 50b is urged to rotate in the opening direction by the first elastic body 60 attached to the second rotating shaft S2. As a result, the proximal end portion 50a and the distal end portion 50b form a substantially "F" shape. A fourth rotating shaft S4 is inserted into the rear end of the base end portion 50a. A roller 51 is provided having a directional axis of rotation S5. The outer peripheral surface of the roller 51 is exposed from the surface (upper surface and lower surface) of the tip portion 50b.

The first elastic body 60 is, for example, a torsion spring. As shown in FIG. 4, the first elastic body 60 is attached to the second rotating shaft S2 and configured to bias the fingertip member 50 so as to rotate in the direction of opening the distal end portion 50a. there is With this configuration, the distal end portion 50b of the fingertip member 50 can be rotated in the closing direction (upward direction) only by a predetermined angle (rotating range in FIG. It is possible to prevent the work object P from being dropped when the plurality of link mechanisms 100a are completely closed while coping with the unevenness of the ground when the part 50b is fed.

The second elastic body 70 is, for example, a compression coil spring. The second elastic body 70 is provided in the elastic body housing portion 42 of the fourth link member 40, and the fourth rotation shaft S4 extends along the arcuate long hole (insertion hole 41) into the fourth link member. It is configured to bias toward the other end of 40 . With this configuration, when the fingertip (tip 50b of the fingertip member 50) of the robot hand 100 is caught by a temple and receives a strong force, only the fingertip can be moved downward to release the hook from the temple (see FIG. 5). ). Therefore, rework due to the robot hand 100 being caught by the vine can be reduced. In addition, after the hooked temple is removed, the second elastic body 70 can restore the fingertip (the distal end portion 50b of the fingertip member 50).

The surrounding member 80 is ring-shaped and provided inside the second link member 20 . By providing the enclosing member 80, the work object P can be prevented from falling from between the plurality of link mechanisms 100a and the fingertip members 50 when the work object P is picked up.

The climbing crop harvesting apparatus 1000 of the present invention described above can be mounted on a vehicle such as a tractor to perform harvesting while moving.

Next, the operation of the climbing crop harvesting apparatus 1000 equipped with the robot hand 100 of the present invention will be described with reference to FIGS. 6 to 8. FIG.

As shown in FIGS. 6 to 8, when harvesting pumpkins or the like using the climbing crop harvesting apparatus 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 members 50 of the robot hand 100 are in the expanded state. Next, the robot hand 100 is lowered from above the work object P, the tip 50b of the fingertip member 50 is brought into contact with the ground, and only the tip 50b is closed (upper direction) so as to be substantially parallel to the ground. Rotate (see FIG. 6(B)). Next, the drive mechanism movable portion 200a moves upward with respect to the drive mechanism fixed portion 200b, thereby starting contraction of the plurality of link mechanisms 100a and the fingertip members 50 of the robot hand 100 in the direction of the central axis C (central portion). (See FIG. 7A). Next, the plurality of link mechanisms 100a and the fingertip members 50 are contracted in the direction of the central axis C (central portion) so that the fingertips (tips 50b of the fingertip members 50) move to the lower portion of the work object P (FIG. 7). (B)). Next, a plurality of fingertips (tips 50b of the fingertip members 50) are inserted between the lower part of the work object P and the ground (see FIG. 8A). Then, the arm mechanism 300 raises the robot hand 100 to lift the work object P (see FIG. 8B). In this way, individual harvesting of climbing crops (eg, heavy crops such as pumpkins) is performed.

Experimental results of harvesting pumpkins using the climbing crop harvesting apparatus 1000 equipped with the robot hand 100 of the present invention will be described below. Table 1 shows the dimensions, shape, etc. of the pumpkins used in the experiment.

Table 2 shows the results of a pumpkin harvesting experiment in which one vine was caught in the robot hand 100 . As shown in Table 2, if one vine is caught, the picking success rate is 90%.

Table 3 shows the results of a pumpkin harvesting experiment in which a plurality of vines were caught on the robot hand 100 . As shown in Table 3, when multiple vines are caught, the probability of successful picking up is 85%.

As described in detail above, according to the present embodiment, the climbing crop harvesting apparatus 1000 includes the robot hand 100 that lifts up the work object P, the drive mechanism 200 for driving the robot hand 100, the robot It has an arm mechanism 300 that freely moves the hand 100 and the drive mechanism 200 within a predetermined range in a three-dimensional space. The robot hand 100 includes a plurality of link mechanisms 100a and a plurality of fingertip members 50 for lifting the work object P from the ground or the like.

The link mechanism 100a is rotatably connected to the first link member 10, one end of which is fixed to the drive mechanism movable portion 200a at the tip of the arm mechanism 300, and the other end of the first link member 10. A second link member 20, a third link member 30 whose proximal end is connected to the drive mechanism movable portion 200a, one end rotatably connected to the distal end of the third link member 30, and the other and a fourth link member 40 having an insertion hole 41 at its end. The fingertip member 50 is composed of a proximal end portion 50a and a distal end portion 50b. The link mechanism 100a further includes a first elastic body 60 attached to the second rotating shaft, a second elastic body 70 provided at the other end of the fourth link member 40, and a second The enclosing member 80 surrounding the work object P provided on the link member 20, the first rotation shaft S1 inserted at the other end of the first link member 10, and the second link member 20 The second rotating shaft S2 inserted at the other end, the third rotating shaft S3 inserted at the tip of the third link member 30, and the base end 50a of the fingertip member 50 and a fourth rotating shaft S4 inserted at the rear end.

As a result, the harvesting of heavy crops such as pumpkins can be mechanized and labor-saving. The work object P can be lifted and transported, and the pressure load applied to the work object P can be reduced. In addition, since it is possible to unhook the vines of climbing crops, it is possible to avoid redoing work due to the vines getting caught. Furthermore, the flexibility of the fingertips of the robot hand 100 is ensured, and the contact resistance with the uneven ground can be suppressed.

Although the robot hand 100 has the four link mechanisms 100a and the fingertip members 50 in the above embodiment, 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 helically inclined with respect to the central axis C.

Further, in the above-described embodiment, the fingertip member 50 is configured by the proximal end portion 50a and the distal end portion 50b, but the present invention is not limited to this. For example, the fingertip member may be composed of one member.

Furthermore, in the above-described embodiment, the robot hand 100 has explained an example in which the work object P is a climbing crop, but the present invention is not limited to this. The present invention can also be applied to work objects other than climbing crops.

Furthermore, in the above-described embodiment, an example in which the second elastic body 70 is provided at the lower end 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 dirt, dust, or the like from entering the elastic body housing portion 42 .

The above-described embodiments are illustrative of the present invention and not restrictive, and the present invention can be implemented in various other variations and modifications. Accordingly, the scope of the present invention is defined only by the scope of the claims and their equivalents.

INDUSTRIAL APPLICABILITY The robot hand and climbing crop harvesting apparatus of the present invention can be used for the purpose of mechanizing the harvesting of climbing crops such as pumpkins, watermelons and melons to reduce the labor burden.

REFERENCE SIGNS LIST 10 first link member 20 second link member 30 third link member 40, 40A fourth link member 41 insertion hole (arc-shaped oblong hole)
42 elastic body storage part 50 fingertip member 50a base end part 50b tip part 51 rollers 52, 53 rotation control part 60 first elastic body 70 second elastic body 80 enclosing member 100 robot hand 100a link mechanism 200 drive mechanism 200a drive mechanism Movable Part 200b Drive Mechanism Fixing Part 300 Arm Mechanism 1000 Climbing Crop Harvesting Device C Center Axis P Work Object S0 Connection Shaft S1 First Rotational Axis S2 Second Rotational Axis S3 Third Rotational Axis S4 Fourth rotation axis S5 rotation axis

Claims (6)

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 and holding a work object,
each of the plurality of link mechanisms,
a first link member having one end fixed to the distal end of the arm mechanism and having the other end inserted with a first rotating shaft;
a second link member having one end attached to the first rotating shaft and having the other end inserted with a second rotating shaft;
a third link member having a substantially central portion pivotally attached to the first rotating shaft, a base end portion connected to the driving mechanism movable portion, and a tip end portion having a third rotating shaft inserted therein;
a fourth link member having one end axially attached to the third rotating shaft and having an insertion hole at the other end through which the fourth rotating shaft is inserted;
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, and is formed so that the thickness gradually decreases toward the distal end. The fourth rotation shaft of each of the plurality of link mechanisms is configured to be inserted into the
When the proximal end portion of the third link member is operated by the drive mechanism movable portion, each of the plurality of fingertip members is rotated via the fourth link member, and the second link member is moved. is configured to rotate around the first rotation axis. each of the plurality of fingertip members is composed of a proximal end portion and a distal end portion;
The proximal end portion and the distal end portion are connected to each other so as to be rotatable within a predetermined range by the second rotating shaft so as to form a substantially "F" shape. 2. The robot hand according to claim 1, further comprising a first elastic body for urging the distal end portion to rotate in a direction to open the distal end portion. the insertion hole at the other end of the fourth link member is an arc-shaped elongated hole in which the fourth rotating shaft can slide,
A second elastic body is provided at the other end of the fourth link member to bias the fourth rotating shaft toward the other end along the arc-shaped elongated hole. The robot hand according to claim 1 or 2. The distal end portion of the fingertip member is formed so that the thickness gradually decreases toward the distal end, and a roller having a horizontal rotation axis is provided at the distal end portion, and the outer peripheral surface of the roller 4. The robot hand according to claim 2, wherein the robot hand is configured to be exposed from the surface of the part. The robot hand according to any one of claims 1 to 4, wherein the second link member is provided with an enclosing member that encloses the work object. a robot hand according to any one of claims 1 to 5;
a drive mechanism for driving the robot hand;
An apparatus for harvesting climbing crops, comprising: an arm mechanism for freely moving the robot hand and the drive mechanism within a predetermined range in a three-dimensional space.

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