WO2023037439A1

WO2023037439A1 - Robot hand

Info

Publication number: WO2023037439A1
Application number: PCT/JP2021/032987
Authority: WO
Inventors: 浩司白土; 泰義横小路
Original assignee: 三菱電機株式会社; 国立大学法人神戸大学
Priority date: 2021-09-08
Filing date: 2021-09-08
Publication date: 2023-03-16
Also published as: DE112021008207T5; JP7154463B1; JPWO2023037439A1; CN117897262A

Abstract

A robot hand (10) comprises a first finger part (A), a second finger part (B), a base part (20), and a drive part (DA1). The first finger part (A) comprises a base end link part (A1) that is connected to the base part (20), an intermediate link part (A2) that is connected to the base end link part (A1), a tip end link part (A3) that is connected to the intermediate link part (A2), a passive joint part (PA2) that rotatably supports the base end link part (A1) and the intermediate link part (A2), a passive joint part (PA3) that rotatably supports the intermediate link part (A2) and the tip end link part (A3), and a spring element (SA2) that holds the base end link part (A1) and the intermediate link part (A2) in a basic posture.

Description

robot hand

The present disclosure relates to a robot hand that grips an object to be gripped by sandwiching two fingers.

Conventional robot hands are often composed of multiple finger mechanisms with multiple joints and multiple actuators, like human fingers, in order to perform complex tasks. On the other hand, efforts are being made to develop an underactuated robot hand that has a small number of actuators relative to the degree of freedom of the system.

For example, in order to grasp an object of unknown shape or size, a robot hand has been developed that applies underactuation that allows the fingers to wrap around. In Patent Document 1, a linkage finger assembly is provided that includes a proximal joint, an intermediate joint, and a distal joint, each joint being synchronously driven by a single actuator. Specifically, a pulley is provided at each joint, each pulley is rotated by pulling a torsion string wound around each pulley, and each joint is locked and unlocked by an indirect brake mechanism, thereby making various finger assemblies. movement is realized.

Japanese Unexamined Patent Application Publication No. 2017-35780

The robot hand of Patent Document 1 has a problem that its structure is complicated. In addition, when a state in which a plurality of objects to be grasped are closely aligned to a state in which a single object to be grasped is stably grasped, the robot hand of Patent Document 1 manages fine state transitions and responds accordingly. Complicated control such as finger lock is required. Specifically, in the case of performing a scooping operation to cut out one of a plurality of grasped objects that are aligned, and then sliding the grasped object to a state where it can be wrapped and grasped, Patent Document 1 discloses the following. Therefore, complex control operations are required to perform complex transitions of the hand. Therefore, in Patent Document 1, a control operation must be designed for each grasped object, and it may be difficult to generate a finger motion depending on the type of grasped object.

The present disclosure has been made in view of the above, and aims to obtain a robot hand that achieves a scooping operation and a wrapped grip with a simple structure that can be made smaller and simple control.

In order to solve the above-described problems and achieve the purpose, the robot hand in the present disclosure grips the gripping target. The robot hand includes a finger having a first finger and a second finger opposed to the first finger, a base provided on an arm of the robot, and connected to the base, the first finger and the second finger. and a drive for rotationally driving at least one of the fingers. The first finger includes a first link connected to the base, a second link connected to the first link, a third link connected to the second link, and the first link. a first passive joint portion rotatably supporting the second link portion; a second passive joint portion rotatably supporting the second link portion and the third link portion; the first link portion and the second link portion and a first elastic body that holds the and in the basic posture.

According to the robot hand of the present disclosure, it is possible to achieve scooping operation and wrapping gripping with a simple structure that can be miniaturized and simple control.

Conceptual diagram showing a robot system to which the robot hands of the first to twelfth embodiments are applied 1 is a conceptual diagram showing a robot hand according to Embodiment 1; FIG. FIG. 4 is a conceptual diagram showing a first modification of the robot hand of Embodiment 1; FIG. 4 is a conceptual diagram showing a second modification of the robot hand of Embodiment 1; FIG. 4 is a diagram for explaining the motion when the robot hand of the first modification of the first embodiment shown in FIG. 3 grips a gripping object; FIG. 4 is a conceptual diagram showing the configuration of the distal end portion of the robot hand according to Embodiment 2; FIG. 4 is a conceptual diagram showing a configuration of a modified example of the distal end portion of the robot hand according to Embodiment 2; FIG. 11 is a conceptual diagram showing the configuration of the distal end portion of the robot hand according to Embodiment 3; FIG. 11 is a conceptual diagram showing the posture of the tip portion when the robot hand of Embodiment 3 grips a flat object to be gripped that is laid flat on the floor; FIG. 11 is a conceptual diagram showing the configuration of the distal end portion of the robot hand according to Embodiment 4; FIG. 11 is a conceptual diagram showing the state of the tip portion when the robot hand of Embodiment 4 grips the gripping target; FIG. 12 is a conceptual diagram showing the posture of the tip portion when the robot hand of Embodiment 4 grips a flat object to be gripped that is laid flat on the floor; FIG. 11 is a conceptual diagram showing the configuration of the tip portion of the robot hand according to Embodiment 5; Conceptual diagram showing the configuration of the robot hand of Embodiment 6 FIG. 11 is a perspective view showing the configuration of a robot hand according to Embodiment 6; Conceptual diagram showing the configuration of the robot hand of Embodiment 7 Conceptual diagram showing the configuration of the robot hand of Embodiment 8 Conceptual diagram showing the configuration of the robot hand of the ninth embodiment Conceptual diagram showing the configuration of the robot hand of the tenth embodiment Conceptual diagram showing the configuration of the robot hand of the tenth embodiment FIG. 11 is a conceptual diagram showing the configuration of a robot hand according to Embodiment 11; Conceptual diagram showing the configuration of the robot hand of the twelfth embodiment FIG. 20 is a perspective view showing the configuration of a robot hand according to Embodiment 12;

The robot hand according to the embodiment will be described in detail below based on the drawings.

FIG. 1 is a conceptual diagram showing a robot system to which the robot hands of Embodiments 1 to 12 are applied. This robot system comprises a robot 1 , a robot hand 10 and a robot controller 2 . The robot 1 has multiple arms 5 . A robot hand 10 is connected to the tip of the arm 5 of the robot 1 . The robot hand 10 is controlled by the robot control device 2 and grips the gripping target W. As shown in FIG.

Embodiment 1.
FIG. 2 is a conceptual diagram showing the robot hand 10 of Embodiment 1. FIG. As shown in FIG. 2, the robot hand 10 includes a base 20, and a first finger A and a second finger B attached to the base 20 and facing each other. The first finger portion A includes a drive portion DA1, a base end link portion A1 as a first link portion, a passive joint portion PA2 as a first passive joint portion, an intermediate link portion A2 as a second link portion, It has a passive joint part PA3 as a second passive joint part, a tip link part A3 as a third link part, and a spring element SA2 as a first elastic body. The second finger B has a proximal link portion B1. The proximal link portion B1 also functions as a distal link portion. A passive joint is a joint that is not driven by an actuator such as a motor.

The base 20 is, for example, cylindrical and has a central axis. The drive part DA1 is fixed to the base part 20 . The driving part DA1 rotatably supports the base end link part A1 and rotationally drives the base end link part A1. The base end link portion A1 is rotationally driven around the driving portion DA1 by the driving portion DA1. The passive joint portion PA2 rotatably connects the distal end side of the proximal link portion A1 and the proximal end side of the intermediate link portion A2. The intermediate link portion A2 is rotationally driven around the passive joint portion PA2. The spring element SA2 connects the proximal link portion A1 and the intermediate link portion A2 with a preset tension, and is adjusted so that the proximal link portion A1 and the intermediate link portion A2 are balanced at an angle θ1. That is, the spring element SA2 holds the base end link portion A1 and the intermediate link portion A2 in the basic posture. θ1 is 90 degrees or more. θ1 represents the angle of the finger pad side. The passive joint part PA3 rotatably connects the distal end side of the intermediate link part A2 and the proximal end side of the distal link part A3. The tip link portion A3 is rotationally driven around the passive joint portion PA3. Since the tip link part A3 is connected to the passive joint part PA3, its posture changes when it is pressed against the environment. Although not shown, the tip link portion A3 preferably has a tapered shape so that the object to be grasped can be easily grasped. An elastic body other than a spring may be used as the spring element SA2 connected to the base end link portion A1 and the intermediate link portion A2.

The base end link portion B1 is fixed to the base portion 20 and does not move relative to the base portion 20 .

FIG. 3 is a conceptual diagram showing a first modified example of the robot hand 10 of Embodiment 1. FIG. The robot hand 10 shown in FIG. 3 includes a base 20, and a first finger A and a second finger B attached to the base 20 and opposed to each other. The first finger portion A shown in FIG. 3 and the first finger portion A shown in FIG. 2 have the same configuration, and redundant description will be omitted.

The second finger portion B shown in FIG. 3 includes a proximal link portion B1 as a fourth link portion, a passive joint portion PB2 as a third passive joint portion, a distal link portion B2 as a fifth link portion, and a 2, a spring element SB2 as an elastic body. The base end link portion B1 is fixed to the base portion 20 . The passive joint portion PB2 rotatably connects the distal end side of the proximal end link portion B1 and the proximal end side of the distal end link portion B2. The tip link portion B2 is rotationally driven around the passive joint portion PB2. The spring element SB2 connects the proximal end link portion B1 and the distal end link portion B2 with a preset tension, and the rigidity is adjusted so that the proximal end link portion B1 and the distal end link portion B2 are balanced at an angle θ2. . θ2 is 90 degrees or more. θ2 represents the angle of the finger pad side.

As shown in FIG. 3, the spring elements SA2 and SB2 are connected so as to apply tension clockwise around the passive joints PA2 and PB2, but the invention is not limited to this. For example, the spring elements SA2 and SB2 may be connected to apply tension in the counterclockwise direction around the passive joints PA2 and PB2, or may be connected to apply tension in both the clockwise and counterclockwise directions. .

By adopting such a configuration, the width between the first finger A and the second finger B is too wide, and the gripped object W falls while being gripped, and the gripped object W falls over the first finger. It is possible to reduce the situation in which the object comes out of the space between A and the second finger B and cannot be gripped.

It should be noted that the environment refers to, in addition to the gripping object W, the floor surface or wall surface on which the gripping object W is arranged, or the surface of an object around the gripping object W. That is, when gripping the gripping object W, when the robot hand 10 is moved by moving the robot 1, the fingertips touch and receive an external force.

FIG. 4 is a conceptual diagram showing a second modification of the robot hand 10 of Embodiment 1. FIG. In the second modification shown in FIG. 4, the first passive joint PA2 of the first finger A is provided with a stopper STA1, and the passive joint PA3 is provided with a stopper STA2. The stopper STA1 as a first stopper is, for example, a plate member provided outside the distal end of the base end link portion A1, and limits the movable range in the direction in which the intermediate link portion A2 spreads with respect to the base end link portion A1. is provided as follows. The stopper STA2 is, for example, a plate member provided outside the tip of the intermediate link portion A2, and is provided so as to limit the movable range in the direction in which the tip link portion A3 spreads with respect to the intermediate link portion A2. By providing such stoppers STA1 and STA2, reaction forces F1 and F2 are generated from the grasped object W to the first finger portion A when the grasped object W is grasped. Such a stopper may be provided at the passive joint PB2 of the second finger B shown in FIG. Alternatively, the first finger portion A may be provided with only one of the stoppers STA1 and STA2.

FIG. 5 is a diagram for explaining the movement when the robot hand 10 of the first modification of the first embodiment shown in FIG. 3 grips the gripping object W1. In this operation example, one grasped object W1 is scooped from a plurality of grasped objects W1, W2, W3, . be. The objects to be grasped W1, W2, W3, . . . are thin and have a flat rectangular parallelepiped shape. A plurality of grasped objects W1, W2, W3, . . .

First, as shown in the left diagram of FIG. 5, the robot control device 2 causes the robot 1 to move the base 20 of the robot hand 10 and select one of the plurality of gripped objects W1, W2, W3, . . . , the tip of the tip link portion A3 of the first finger A is inserted between the gripping object W1 at the forefront and the gripping object W2 at the second position. Movement of the base 20 is performed by movement of the robot 1 .

In the right diagram of FIG. 5, three operating states are shown for the first finger A, and two operating states are shown for the second finger B. Next, the robot control device 2 causes the robot 1 to move the base 20, and as shown in the left operation state of the first finger A in the right diagram of FIG. is pressed against the second grasped object W2. At this time, the tip link portion A3 is pushed by coming into contact with the second grasped object W2, and moves toward the second finger portion B side, as indicated by the arrow E1, with the passive joint portion PA3 as the center. to start rotating motion. At this time, the tip link portion A3 passively moves due to the reaction force generated by the contact with the grasped object W2. This passive motion rotates the graspable object W1 to separate it from the aligned row of graspable objects. Such detachment is called "isolation", and the feature of the first embodiment is the configuration of the tip link portion A3 for achieving isolation. The isolation operation using the tip link portion A3 has the following advantages compared to the isolation operation performed by simply pressing the finger.

That is, at the initial stage of gripping, the gaps in which the fingers enter become larger, making it easier to pinch the gripped object. In addition, the time for sliding the finger on the surface of the grasped object W1 is reduced, and the grasped object W1 is less likely to be damaged.

After that, as shown in the middle operation state and the right operation state of the first finger A in the right drawing of FIG. The finger portion A and the second finger portion B are sandwiched to wrap and grip. At this time, the tip link portion B2 of the second finger portion B is pushed by the grasped object W1 and rotates around the passive joint portion PB2 from the state indicated by the broken line to the state indicated by the solid line. Further, during this gripping operation, the gripped object W1 slides on the floor Q due to the rotational movement of the base end link portion A1. Further, when the first finger A is closed by the driving part DA1, the tip link part A3 and the intermediate link part A2 passively move along the surface of the grasped object W1.

According to the robot hand 10 of Embodiment 1, it is also possible to grip a thin and flat object to be gripped W1 as shown in FIG. can be done. First, the base 20 of the robot hand 10 is moved by the robot 1, the rear side of the tip link part A3 is pressed against the floor Q, and the tip link part A3 is rotated so as to follow the floor Q. Thereafter, the base portion 20 is moved to bring the tip link portion A3 closer to the grasped object W1. Further, by driving the driving part DA1 to rotate the first finger part A in the closing direction, the flat object to be grasped W1 placed on the floor Q can be grasped.

Next, the state in which the spring element SA2 adjusts the intermediate link portion A2 to balance with the base end link portion A1 at an angle θ1 will be described.

As shown in FIG. 2, even if the passive joint PA2 is displaced, the spring element SA2 acts to return it to the basic posture. That is, the spring element SA2 exerts a restoring force to return to the basic posture. The basic posture indicates the initial posture when the robot hand 10 starts gripping an object to be gripped.

As an example of a specific basic posture, as shown in FIG. 5, the direction of the central axis of the base 20 of the robot hand 10 is set to be substantially parallel to the direction of gravity, and the base 20 of the robot hand 10 is moved toward the first finger. The proximal end link portion A1, the intermediate link portion A2 and the distal end link portion A3 of A extend downward. However, the posture is not particularly limited as long as the angle θ1 is 90 degrees or more.

Furthermore, the basic posture of the first finger A will be explained. The arm 5 of the robot 1 is moved to bring the base 20 of the robot hand 10 into the basic posture state in which the direction of the central axis of the base 20 coincides with the direction of gravity, as described above. With the base 20 in the basic posture, the robot hand 10 is opened, the arm 5 is moved to bring the robot hand 10 closer to the object to be gripped, and the drive unit DA1 of the robot hand 10 is driven to close and grip. Grasp an object. The base end link portion A1 rotates in the opening direction to a horizontal position on the ground, and rotates in the closing direction to a completely closed state.

Adjust so that the intermediate link A2 is aligned with the direction of gravity when the proximal link A1 is horizontal to the ground. The reason for adjusting the intermediate link part A2 so as to match the direction of gravity is that the gaps between the grasped objects aligned so as to overlap each other are often parallel or slightly inclined to the direction of gravity. When inserting the tip link portion A3 of the first finger portion A of the robot hand 10 into such a gap, setting the intermediate link portion A2 so as to substantially match the direction of gravity makes it possible to grasp the object most effectively. Can grasp objects.

As described above, a state in which the base end link portion A1 is closed from the horizontal and the intermediate link portion A2 faces the direction of gravity is a suitable basic posture in the first embodiment. Here, focusing on the angle θ1 formed by the proximal link portion A1 and the intermediate link portion A2, there is a basic posture in the closing direction from the horizontal state of the proximal link portion A1, and the intermediate link portion A2 follows the direction of gravity. Then, it can be seen that the angle θ1 is always 90 degrees or more. In other words, the robot hand 10 of Embodiment 1 can be used under favorable conditions if the angle θ1 formed by the base end link portion A1 and the intermediate link portion A2 is 90 degrees or more.

In addition, in the robot hand 10 of Embodiment 1, when the first finger A is opened after performing a grasping operation, normally, gravity automatically returns to the original basic posture. The spring element SA2 added to the passive joint part PA2 is expected to generate an appropriate drag force and make it difficult to displace when gripping an object to be gripped or when the intermediate link part A2 comes into contact with the environment. It is not expected that the intermediate link portion A2 will not be able to follow the gravity and assume the downward posture due to the influence of the spring element SA2 in the state of the basic posture.

That is, it is desirable to adjust the spring element SA2 so that it assumes the basic posture in the state of its natural length. The hardness of the spring of the spring element SA2 should be adjusted to a hardness suitable for separating one grasped object from the aligned state. Specifically, the hardness is adjusted so that the intermediate link portion A2 does not open completely as the driving portion DA1 is driven and the base end link portion A1 moves to close.

Here, there are a plurality of structural forms for the robot 1 to which the robot hand 10 is attached. A typical example of the mechanism of the robot 1 is a serial link mechanism or a parallel link mechanism. The serial link mechanism has a structure in which links are arranged in series in a cantilevered state from a fixed position on the floor, and is characterized by a wide movable range. The parallel link mechanism has a closed link structure and is characterized by high rigidity and high speed operation.

Since the movable range of the robot differs depending on the structural form of the robot 1, when realizing the movement of the robot hand 10 described above, depending on the system, the movable range may be narrow and cannot be realized. be done. Each embodiment can be applied to any mechanism as long as the base 20 of the robot 1 can be translated and rotated relative to the object to be grasped. That is, each embodiment does not particularly limit the structural form of the robot 1 .

Also, with regard to the drive unit DA1, although a rotary joint has been described, the drive source may be arranged at another position via a belt (not shown), for example, as long as it is a joint that rotates. Further, if the base end link portion A1 can be rotated, the drive portion DA1 may be replaced with a passive joint portion, and the base end link portion A1 may be pushed by the drive portion DA1 that performs linear motion. . In other words, the proximal end link portion A1 may be configured so as to be able to move around the rotational joint with respect to the base portion 20 .

As for the passive joint PA2, the passive joint PA3, and the passive joint PB2, any bearings such as rolling bearings, roller bearings, and slide bearings may be adopted as long as they rotate smoothly around one axis. good. The passive joint portion PA2, the passive joint portion PA3, and the passive joint portion PB2 are configured to be rotationally displaced according to the rotational torque based on the force acting on each link portion from the outside and the rotational frictional force of the bearing. For the passive joint PA2, the passive joint PA3, and the passive joint PB2, a spring is attached between the fixed part and the rotating part of each passive joint in order to return them to their original positions for each operation. can take the configuration of

As described above, in Patent Document 1, each joint is connected to each other by a pulley and a twisted string, and each joint performs an interlocked motion, but Embodiment 1 does not have such a configuration. In the mechanism of Patent Document 1, when one grasped object is isolated from a plurality of grasped objects aligned as described above, an external force acts only on the link portions at the tips of the fingers. Occasionally, the above-described operation of tearing off an article as a grasped object from an adjacent article does not occur. On the other hand, according to the robot hand 10 of Embodiment 1, since the passive joint PA3 at the forefront operates without interlocking with the other joints, only the passive joint PA3 to which the tip link A3 is connected generates a joint displacement due to a reaction force from the gripped object, and can realize an operation of tearing off the gripped object from an adjacent article.

As described above, according to the first embodiment, the state-of-the-art passive joint PA3 operates without interlocking with other joints. It is possible to realize an isolation operation including enveloping grip and improve the success rate of the isolation operation. This can improve the productivity of the automated robot system.

Embodiment 2.
FIG. 6 is a conceptual diagram showing the configuration of the tip of the robot hand according to the second embodiment. In the second embodiment, a tapered finger pad 21 is further provided at the portion of the first finger A and the second finger B of the first embodiment that contacts the grasped object. A finger pad 21 as a first finger pad has a shape that is thick on the base end side and tapers toward the tip side. FIG. 6 shows the tip of the first finger A, and the finger pulp 21 is fixed to the tip of the tip link A3. The finger pad 21 is provided in order to increase the contact area with the grasped object, and has a shape suitable for direct contact with the grasped object and is made of a flexible material. For example, materials may be chosen to increase the coefficient of friction, or antimicrobial materials for hygiene in contact with the grasped object.

FIG. 7 is a conceptual diagram showing a configuration of a modified example of the distal end portion of the robot hand of Embodiment 2. FIG. In FIG. 7, the tip link portion A3' is composed of the link portion 21a and the tapered finger pad 21b, and the link portion 21a and the finger pad 21b are made of the same flexible material.

As described above, according to Embodiment 2, since finger pads made of a flexible material are provided at the tips of the first finger A and the second finger B, the success rate of gripping is improved, and the yield is improved.

Embodiment 3.
FIG. 8 is a conceptual diagram showing the configuration of the tip of the robot hand according to the third embodiment. In Embodiment 3, the shape of the tip link portion A3 of the first finger A of Embodiment 1 is changed. In the tip link portion A3 of Embodiment 3, the back surface portion 22 is formed of a plane parallel to the central axis of the intermediate link portion A2. In the tip link portion A3 of Embodiment 3, the back surface portion 22 is formed of a plane parallel to the direction in which the central axis of the intermediate link portion A2 extends. Further, on the finger pad side of the tip link portion A3 of Embodiment 3, the base end portion 23 close to the passive joint portion PA3 has a convex shape protruding toward the front surface side inside the passive joint portion PA3. , and the distal end portion 24 has a tapered shape. In addition, the proximal end portion 23 and the distal end portion 24 are not connected in a sloped manner, but are connected so as to have a steep step, and the distal end portion 24 is connected to the proximal end portion 23 having a convex shape. concave.

A feature of the robot hand of Embodiment 3 is that it is possible to grasp a grasped object that was difficult to pick up with a simply symmetrically tapered toe structure. As shown in FIG. 5, in order to perform the action of inserting a finger between gripped objects, the structure of the tip link portion A3 needs to be tapered. Also, when inserting a finger into the gripped object leaning against the wall surface when taking out the last one gripped object, the finger must be in a shape that follows the wall. The robot hand of Embodiment 3 has a structure that facilitates insertion of a finger in such a case.

The movement of the robot hand in Embodiment 3 will be explained. The robot 1 is used to move the base 20 of the robot hand 10 to press the tip link A3 against the environment, so that the tip link A3 passively transitions to the environment. Before starting gripping, the robot hand 10 is moved in the designed approach direction for gripping, taking a basic posture in which gripping is likely to succeed.

Here, as a basic posture for gripping, a state in which the tip link portion A3 hangs down by its own weight with respect to the intermediate link portion A2 is created. As shown in FIG. 8, the robot hand 10 has a protruding proximal end portion 23 on the finger pad side of the distal link portion A3, and a distal end portion 24 that tapers toward the distal end.

In addition, the rear portion 22 of the tip link portion A3 has a shape that allows it to take a posture parallel to the wall surface when it hangs down under its own weight. That is, the back surface portion 22 of the tip link portion A3 is designed so that the fingertips and the back surface portion 22 are aligned substantially on the same straight line when it hangs down under its own weight. Further, the finger pad side has a convex base end portion 23 and a tip end portion 24 that tapers toward the tip. By providing the protruding base end portion 23 on the finger pulp side, it is possible to increase the contact surface with respect to the object to be grasped. As described above, the robot hand according to the third embodiment has the distal end portion 24 that tapers toward the distal end, which facilitates isolation. Therefore, the object to be grasped can be stably grasped.

When the robot hand of Embodiment 3 is attached to the robot 1 and used, the basic posture of the fingertips of the robot hand is such that the angle formed by the tip link portion A3 and the intermediate link portion A2 is 180 degrees in accordance with gravity. Design as below. For example, as shown in FIG. 5, when the intermediate link portion A2 is vertical to the ground, the angle formed by the intermediate link portion A2 and the tip link portion A3 is 180 degrees.

On the other hand, the base 20 of the robot hand can be tilted slightly clockwise. In this case, the intermediate link A2 is tilted slightly more than vertically with respect to the ground. On the other hand, since the tip link portion A3 takes a substantially vertical posture with respect to the ground, the angle formed by the intermediate link portion A2 and the tip link portion A3 is slightly smaller than 180 degrees.

FIG. 9 is a conceptual diagram showing the posture of the tip when the robot hand of Embodiment 3 grips a flat object to be gripped that is laid flat on the floor. As shown in FIG. 9, with the robot hand of Embodiment 3, the tip link portion A3 can be inserted between the flat object placed flat on the floor and the floor. First, the axial direction of the base portion 20 is slightly tilted, the intermediate link portion A2 is tilted more than perpendicular to the floor surface, and the back side of the tip link portion A3 is brought into contact with the floor surface. While maintaining this posture, the arm 5 of the robot 1 is moved to move the base 20 in the direction of pressing it against the floor surface. As the base portion 20 moves, the tip link portion A3 rotates about the passive joint portion PA3 due to the reaction force generated from the floor surface. By controlling the robot control device 2, the tip link part A3 is placed between the floor and the object to be grasped, which is placed flat on the floor, while the tip link part A3 remains in the posture changed by the rotation of the passive joint part PA3. The first finger A or the arm 5 of the robot 1 is moved in the insertion direction. There are two methods for moving the tip link part A3 in the direction of insertion: a method of driving the first finger A by the driving part DA1, and a method of moving the base part 20 by the arm 5 of the robot 1. Either method may be used. . When the tip link part A3 is moved in the direction of inserting it between the floor surface and the bottom surface of the gripped object, the tip link part A3 is restrained by the floor surface, and the tip link part A3 smoothly moves between the floor surface and the bottom surface of the gripped object. , and the tip link portion A3 can transition to a state in which the lower surface of the gripped object is supported.

Further, when the tip link portion A3 is inserted between the floor surface and the object to be grasped, when the first finger portion A is driven by the driving portion DA1, the first finger portion A is moved by the driving portion DA1. The intermediate link portion A2 approaches the floor surface along with the overall rotational motion. At this time, the tip link portion A3 passively rotates according to both the reaction force from the floor surface and the motion of the connecting portion with the intermediate link portion A2. As a result, the back surface of the tip link portion A3 approaches a posture in which it is almost parallel to the floor as a passive movement. This movement allows the tip link portion A3 to smoothly slide onto the bottom surface of the gripped object, and the tip link portion A3 can transition to a state in which it supports the bottom surface of the gripped object.

In the above example, a flat object to be grasped placed on the floor was explained, but the same effect can be expected when a flat object to be grasped that is leaned against the wall is isolated from the wall and grasped.

It is desirable that the tip of the finger pad of the tip link portion A3 is recessed and tapered, but a soft material is attached to the portion of the finger pad that touches the object to be grasped, so that the surface shape of the object to be grasped is improved. A soft member may be further provided on the finger pad because it is more difficult to drop the gripped object if it is tightly attached to the finger pad.

As described above, in the distal link portion A3 of Embodiment 3, the back surface portion 22 is configured by a plane parallel to the intermediate link portion A2, and on the finger pad side, the convex-shaped proximal portion 23 and the tapered distal end portion are formed. Since it has the portion 24, it becomes possible to smoothly isolate the grasped object closely arranged on the floor surface or the wall surface. This improves the production efficiency of the automated robot system.

Embodiment 4.
FIG. 10 is a conceptual diagram showing the configuration of the tip of the robot hand according to the fourth embodiment. FIG. 11 is a conceptual diagram showing the state of the tip when the robot hand of Embodiment 4 grips the gripping target. In the tip link part A3 of the first finger part A of the robot hand of the fourth embodiment, the back part has a protruding part 25 that extends above the passive joint part PA3 and protrudes to the back side. In other words, the tip link portion A3 of the first finger portion A of the robot hand of Embodiment 4 extends above the passive joint portion PA3 and extends to the rear side of the passive joint portion PA3 in a posture that hangs down under its own weight. It has a protrusion 25 that protrudes to the side. The gripping portion 26 for gripping the gripping object W on the finger pulp side of the tip link portion A3 has a curved shape, and a friction member 27 such as rubber is provided on the surface thereof. In other words, the tip side from the passive joint part PA3 of the tip link part A3 of the first finger part A of the robot hand of the fourth embodiment is tapered, and the tip side from the passive joint part PA3 of the tip link part A3 is tapered. The base end portion of protrudes to the rear surface side and the front surface side.

FIG. 12 is a conceptual diagram showing the posture of the tip portion when the robot hand of Embodiment 4 grips a flat object to be gripped that is laid flat on the floor. The left figure in FIG. 12 shows the state when the tip end side of the tip link part A3 is in contact with the floor (or wall surface), and the right figure in FIG. (or wall surface). As shown in the left diagram of FIG. 12, when the tip side of the tip link portion A3 comes into contact with the floor surface, the tip link portion A3 rotates counterclockwise due to the reaction force from the floor surface indicated by the arrow. On the other hand, as shown in the right diagram of FIG. 12, when the protruding portion 25 on the root side of the tip link portion A3 comes into contact with the floor surface, the tip link portion A3 rotates clockwise due to the reaction force from the floor surface indicated by the arrow. rotate to Therefore, it is possible to automatically adjust the front end link portion A3 to a posture in which the front end portion of the front end link portion A3 easily enters between the object to be grasped and the floor (or wall surface).

As described above, according to the fourth embodiment, since the back surface of the tip link portion A3 is provided with the protruding portion 25 that extends to the upper side of the passive joint portion PA3 and protrudes toward the back side, the object to be grasped and the floor surface are provided. (or a wall surface), the tip link part A3 can be automatically adjusted to a posture in which the tip part of the tip link part A3 easily enters. This makes it possible to smoothly isolate a grasped object that is closely arranged on the floor surface (or wall surface). This improves the production efficiency of the automated robot system.

Embodiment 5.
FIG. 13 is a conceptual diagram showing the configuration of the tip of the robot hand according to the fifth embodiment. The left diagram of FIG. 13 shows the attitude of the robot hand when it is in the initial attitude, and the right diagram of FIG. there is In the fifth embodiment, a spring element SA3 is also added around the passive joint PA3 to the robot hand 10 of the first embodiment. The elastic force of the spring element SA3 is weaker than the stiffness of the spring element SA2 around the passive joint PA2. That is, it is composed of a spring that becomes weaker toward the tip.

In this configuration, the spring element SA3 on the tip side can be bent first, and then the spring element SA2 can be bent. It is possible to return to a certain basic posture while showing good behavior. As for the method of mounting the spring, any one of the three patterns of applying tension in the clockwise direction around the passive joint PA3, applying tension in the counterclockwise direction, and applying tension from both directions may be used.

When the same gripping operation is repeated, the initial position of the tip link part A3, which moves passively, changes each time due to the influence of friction, etc., or the shape of the fingertip that follows the wall or floor , the fingertip of the tip link portion A3 may come into contact with the object to be grasped, and the desired fingertip motion may not occur.

According to the fifth embodiment, since the spring element SA3 on the distal end side bends first and then the spring element SA2 bends, it is possible to stably separate the fingertip from the wall surface or the floor surface every time. and the grasping success rate is improved. As a result, the production efficiency of the production system can be increased.

Embodiment 6.
FIG. 14 is a conceptual diagram showing the configuration of a robot hand according to Embodiment 6. FIG. 15 is a perspective view showing the configuration of a robot hand according to Embodiment 6. FIG. In the sixth embodiment, the robot hand 10 of the first embodiment is further provided with a robot fixing portion 30 for connection with the robot 1, and the fourth embodiment is provided between the base portion 20 of the robot hand 10 and the robot fixing portion 30. It further includes a passive joint portion P0 as a passive joint portion, and further includes a spring element S0 as a third elastic body for holding the passive joint portion P0 in the initial position. Assume that the initial position of the passive joint portion P0 is a position where the direction of the central axis of the base portion 20 is inclined so that the fingertips of the robot hand 10 are parallel to the direction of gravity.

　In the conventional mechanism, the wrist of the robot arm had to be tilted with respect to the wall or floor when pressing the fingertips of the robot hand along the wall or floor. At this time, if the wrist of the arm is tilted, the elbow position of the arm will protrude into the environment, or the wrist will interfere with the environment, or the range of motion will be insufficient and the wall or floor will not fit. There was a problem that it was not possible to take a tilted state.

By adopting the configuration of the sixth embodiment, when the tip link portion A3 is pressed against the floor surface or the wall surface as shown in the third embodiment without greatly changing the attitude of the base portion 20 by the arm 5 of the robot 1. In addition, the tip of the tip link portion A3 can automatically enter between the flat gripped object and the floor or wall surface.

Especially in a robot system, when the posture of the tip of the robot hand is changed by the movement of the robot arm, the elbow of the robot arm may interfere with the environment. In the configuration of Embodiment 6, since the robot fixing portion 30 and the passive joint portion P0 are provided, the posture change of the arm 5 of the robot 1 can be reduced. can be raised. As a result, the production efficiency of the production system can be increased.

Embodiment 7.
FIG. 16 is a conceptual diagram showing the configuration of a robot hand according to Embodiment 7. FIG. In the robot hand of Embodiment 7, the first finger A and the second finger B have the same structure, and the first finger A and the second finger B have a symmetrical structure. The first finger portion A includes a passive joint portion PA1 as a seventh passive joint portion, a proximal link portion A1, a passive joint portion PA2, an intermediate link portion A2, a passive joint portion PA3, and a distal link portion A3. , a stopper STA1 as a second stopper, a spring element SA2, and a soft friction member 27 such as rubber. The second finger portion B includes a passive joint portion PB1 as an eighth passive joint portion, a base end link portion B1 as a sixth link portion, a passive joint portion PB2 as a fifth passive joint portion, and a seventh link portion. a passive joint portion PB3 as a sixth passive joint portion; a tip link portion B3 as an eighth link portion; a stopper STB1 as a second stopper; and a spring as a fourth elastic body It has an element SB2 and a friction member 27 .

The first finger portion A of Embodiment 7 replaces the drive portion DA1 of Embodiment 1 with a passive joint portion PA1 that does not have a drive mechanism. The base portion 20 has a rotation drive portion D0 as a drive source and a transmission mechanism portion G0 that transmits the rotation of the rotation drive portion D0 to the passive joint portions PA1 and PB1. When the rotational drive unit D0 is rotationally driven, the passive joints PA1 and PB1 are synchronously rotated. The transmission mechanism G0 may be a gear, or may be a combination of a timing belt and a pulley. Further, the mechanism is bilaterally symmetrical, the transmission mechanism transmits power to only one of the first finger A and the second finger B, and either the first finger A or the second finger B is operated. A configuration in which only one is driven for sandwiching is also possible.

With such a configuration of the seventh embodiment, when the tip link portion A3 is pressed against the floor surface or the wall surface as shown in the third embodiment, the first finger portion A and the second finger portion Any of B can be similarly isolated. Therefore, when the isolation operation is performed by the first finger A or the second finger B, the posture change of the robot hand for directing the position of the fingertip toward the object to be grasped becomes small. movement can be reduced. As a result, the gripping success rate and gripping efficiency are improved and the productivity of the system is improved.

Embodiment 8.
FIG. 17 is a conceptual diagram showing the configuration of a robot hand according to Embodiment 8. FIG. In the robot hand of the eighth embodiment, the first finger A replaces the driving part DA1 of the first embodiment with a passive joint part PA1 as a tenth passive joint part without a driving mechanism. The first finger portion A includes a passive joint portion PA1, a proximal link portion A1, a passive joint portion PA2, an intermediate link portion A2, a passive joint portion PA3, a distal link portion A3, and a sixth elastic body. It has a spring element SA1 and a spring element SA2. The spring element SA1 holds the passive joint PA1 in the initial position, and the spring element SA2 holds the passive joint PA2 in the initial position.

The second finger portion B includes a driving portion DB1 that rotationally drives the proximal link portion B1, a proximal link portion B1 as a ninth link portion, a passive joint portion PB2 as a ninth passive joint portion, and a second finger portion B1. It has a tip link portion B2 as a 10-link portion and a spring element SB2 as a fifth elastic body. In the eighth embodiment, all joints of the first finger A are passive joints having no driving mechanism, and the second finger B is rotationally driven by the driving section DB1.

In the robot hand of Embodiment 8, translational movement of the base 20 of the robot hand 10 by the arm 5 of the robot 1 causes the robot hand 10 and the grasped object W to come into contact with each other, and the grasped object W is isolated. Furthermore, by driving the driving part DB1 to move the second finger B in the closing direction, the isolation operation by the first finger A and the gripping operation by the first finger A and the second finger B can be performed at the same time. conduct. As a result, the object to be grasped in the robot hand can be transitioned to the grasping completion state at a higher speed than the configuration of the fourth embodiment.

That is, in the eighth embodiment, the second finger portion B bears the fingers that perform the link movement using the driving portion DB1 for sandwiching the gripped object W, and the fingers for isolating the gripped object W are placed on the second finger portion B. is assigned to the first finger A, and by dividing the roles, it becomes possible to transition to the action of pinching the grasped object without waiting for the completion of the isolation operation. Therefore, according to the eighth embodiment, the operation time required for one gripping operation can be shortened, and as a result, the production efficiency of the production system can be improved.

Embodiment 9.
FIG. 18 is a conceptual diagram showing the configuration of a robot hand according to the ninth embodiment. In the robot hand of the ninth embodiment, as in the robot hand of the seventh embodiment, the configurations of the first finger A and the second finger B are the same, and the first finger A and the second finger B are It has a symmetrical structure. In the ninth embodiment, instead of the rotary drive section D0, the transmission mechanism section G0, and the passive joint sections PA1 and PB1 of the seventh embodiment, a rotary joint section JT0 and a drive section D0 are arranged.

The first finger portion A of the robot hand of the ninth embodiment includes a base end link portion A1, a passive joint portion PA2, an intermediate link portion A2, a passive joint portion PA3, a tip link portion A3, and a spring element SA2. , and a stopper STA1 as a fourth stopper that restricts the rotation in the opening direction of the intermediate link portion A2. The second finger portion B of the robot hand of the ninth embodiment includes a base end link portion B1 as an eleventh link portion, a passive joint portion PB2 as an eleventh passive joint portion, and an intermediate link portion as a twelfth link portion. B2′, a passive joint portion PB3 as a twelfth passive joint portion, a tip link portion B3 as a thirteenth link portion, a spring element SB2 as a seventh elastic body, and an intermediate link portion B2′ in the opening direction. and a stopper STB1 as a fifth stopper that restricts rotation.

The proximal end link portion A1 of the first finger portion A and the proximal end link portion B1 of the second finger portion B extend from the rotary joint portion JT0 toward the driving portion D0. That is, the proximal link portion A1 of the first finger A has a first extending portion extending in the opposite direction to the intermediate link portion A2, and the proximal link portion B1 of the second finger B has an intermediate It has a second extending portion extending in the opposite direction to the link portion B2'. The driving portion D0 is connected to the first extending portion of the proximal link portion A1 and the second extending portion of the proximal link portion B1, and the first extending portion and the second extending portion are connected to each other using the connection point as a point of action. By pressing the base end link portions A1 and B1, the base end link portions A1 and B1 are rotationally driven with the rotary joint portion JT0 as a fulcrum. In the ninth embodiment, the drive unit D0 is operated to rotate the first finger A and the second finger B in a crossed state on the same rotation axis via the rotary joint JT0. The movement of the fingers at this time works on the same principle as scissors.

By adopting the configuration of the ninth embodiment, it is possible to dispose the drive unit D0 as an actuator in the robot hand at a position farther away from the fingertips. In addition, by arranging the point of action of the drive unit D0 as an actuator in the robot hand away from the rotary joint JT0, the required output can be reduced by the principle of leverage, and the output can be suppressed when selecting the actuator. As a result, it is possible to select a compact actuator with a small output of the drive unit D0, and it is possible to reduce the thickness of the robot hand and to miniaturize the robot hand.

As described above, according to the ninth embodiment, it is possible to reduce the number of cases where the object cannot be gripped due to interference with the environment, shorten the average operation time required for gripping, and as a result, increase the production efficiency of the production system. .

Embodiment 10.
FIG. 19 is a conceptual diagram showing the configuration of a robot hand according to the tenth embodiment. FIG. 20 is a conceptual diagram showing the configuration of a robot hand according to the tenth embodiment. FIG. 20 shows a state in which the tip of the robot hand is viewed obliquely. In the robot hand of the tenth embodiment, the first finger part A replaces the passive joint part PA3 of the first embodiment with a plurality of passive joint parts PA3α, PA3β, and PA3γ, and replaces the tip link part A3 with a plurality of tip links. It is replaced with parts A3α, A3β and A3γ. The plurality of passive joints PA3α, PA3β, PA3γ are coaxially connected, and the direction of the rotation axis of the plurality of passive joints PA3α, PA3β, PA3γ is the same as that of the passive joint PA2. Specifically, the passive joint PA3α is connected to the intermediate link A2, and the passive joints PA3β and PA3γ are coaxially connected. Tip link portions A3α, A3β, and A3γ are connected to the passive joint portions PA3α, PA3β, and PA3γ, respectively. The tip link portions A3α, A3β, and A3γ each have a finger pad that is thick on the base end side and tapered toward the tip side.

According to the configuration of the tenth embodiment, since a plurality of tip link portions A3α, A3β, and A3γ are provided, when an operation of inserting a finger into a grasped object is performed in an operation for isolating a grasped object, the first Compared to the case where one finger portion A has one tip link portion, it becomes easier to insert a finger. In the method of using one tip link portion, it is difficult to smoothly insert the fingertip when the object to be grasped has an uneven shape. In particular, when there are irregularities and variations in individual shapes, such as food, it is better to have a plurality of tip link portions so that the fingers can smoothly slide between the grasped objects. . This is because each finger moves independently while following the surface of the grasped object, so that the tips of the tip link portions follow the shape of the grasped object, and the tip link portions A3α, A3β, and A3γ are securely attached. This is because it is in a state of touching In this way, not only can the isolation operation be smoothly shifted by changing the posture of the first finger, but also the contact surface can be increased, so that a stable grip can be realized.

In the tenth embodiment, the number of tip link portions is not limited to three, and any number may be adopted as long as the number is two or more. Further, in the tenth embodiment, as in the configuration of the eighth embodiment shown in FIG. 17, when the second finger B is driven by the drive unit DB1, the second finger B is The present invention can also be applied to a first finger A shown at 20 having a base end link portion, an intermediate link portion, and a tip end link portion. When the tenth embodiment is applied, the second finger portion B includes a proximal end link portion as a fourteenth link portion, an intermediate link portion as a fifteenth link portion, a distal end link portion as a sixteenth link portion, A passive joint portion as a thirteenth passive joint portion connecting the proximal link portion and the intermediate link portion, a passive joint portion as a fourteenth passive joint portion connecting the intermediate link portion and the distal link portion, and a proximal link and a spring element as an eighth elastic body connecting the part and the intermediate link part, and the tip link part has a finger pad that is thick on the base end side and tapered toward the tip side. Further, there are a plurality of tip link portions having finger pads, a plurality of passive joint portions connecting the tip link portions, and the plurality of passive joint portions are coaxially connected. Further, the tenth embodiment may be applied to at least one of the first finger portion A and the second finger portion B of the seventh embodiment shown in FIG. 16 or the ninth embodiment shown in FIG.

As described above, according to the tenth embodiment, since the number of tip link portions is increased, the gripping success rate and gripping efficiency are improved, and the productivity of the system is improved.

Embodiment 11.
FIG. 21 is a conceptual diagram showing the configuration of the robot hand according to the eleventh embodiment. In the eleventh embodiment, the spring element SA2 attached to the passive joint PA2 of the first finger A and the passive joint PB2 of the second finger B in the robot hand of the seventh embodiment shown in FIG. The spring element SB2 is removed, and the entire robot hand is covered with a covering member 40 having elasticity. The eleventh embodiment is suitable for performing work in which the robot hand does not want to directly touch the object to be grasped.

Here, since the robot hand of the eleventh embodiment is provided with a passive link fingertip, it is necessary to select the strength of elasticity of the covering member 40 so as to displace the desired amount of displacement in the rotational direction. be. That is, when the robot hand is pressed against the environment, it is necessary to passively move the passive joints PA2 and PA3 to displace each link. Assuming that the initial angle of the passive joint PA2 is θA2 and the initial angle of the passive joint PA3 is θA3, the designed drive ranges of the passive joints PA2 and PA3 are θA2MIN≦θA2≦θA2MAX and θA3MIN≦θA3≦θA3MAX. stipulate. A specified drive range is realized by providing a portion of the covering member 40 having elasticity with a slack 40b and a thin portion 40a.

To make it slack, do the following. The link portion connected to the passive joints PA2 and PA3 has a side that contacts the environment and a side that grips the object to be grasped. form a slack 40b. A similar process is performed on the second finger portion B as well. Further, the thin portion 40a is provided at a symmetrical inner position with respect to the passive joint portions PA2 and PA3 from the position where the slack 40b is provided. This facilitates bending inward when the first finger A or the second finger B is brought into contact with the environment. Furthermore, since the hand is covered with the elastic covering member 40, when the gripped object is gripped and released after contact with the environment, that is, when the force applied to the hand is released, The action of trying to return the whole to the balanced position allows the first finger A and the second finger B to return to their original positions even without the spring elements SA2 and SB2 in the passive joints.

As the elastic covering member 40, a glove material used in food production sites can be exemplified. Specific examples include nitrile rubber, natural rubber, and latex, but the material is not particularly limited. It is also possible to select a non-elastic but hygienic and inexpensive member such as polyethylene, and to give elasticity to the joint only by adhering an elastic covering member from the inside only to the passive joint. With this configuration, it is possible to apply a force to return the joint to its original position while maintaining an appropriate degree of slack so that the joint can be easily rotated.

Thus, according to the eleventh embodiment, it is possible to provide a robot hand equipped with hygienic and disposable gloves, and improve production efficiency from the viewpoint of reducing maintenance costs. In Embodiments 1 to 11, the spring element SA2 attached to the passive joint PA2 of the first finger A, the spring element SA3 attached to the passive joint PA3, and the passive joint of the second finger B The function of each spring element may be realized by removing the spring element SB2 attached to PB2 and covering the robot hand with an elastic covering member 40 having a slack 40b and a thin portion 40a. Also, the covering member 40 may cover at least a portion of the base end link portion, a portion of the intermediate link portion, and the passive joint portion PA2.

Embodiment 12.
FIG. 22 is a conceptual diagram showing the configuration of the robot hand according to the twelfth embodiment. 23 is a perspective view showing the configuration of a robot hand according to Embodiment 12. FIG. In the twelfth embodiment, the stopper STA1 of the robot hand 10 of the first embodiment is replaced with a stopper STA3 having a mechanism for varying the position at which the intermediate link portion A2 is restricted in the rotational direction. As shown in FIG. 23, the stopper STA3 comprises a projection 50 formed at the proximal end of the intermediate link A2, an elongated hole 51 formed at the distal end of the proximal link A1, and a proximal link A1. It consists of a pin 52 fixed to A1. The pin 52 is fixed to the base end link portion A1 and passes through the elongated hole 51 . The pin 52 can be fixed at any position inside the elongated hole 51 . By varying the fixing position of the pin 52, it is possible to vary the rotation angle of the intermediate link portion A2 when the pin 52 abuts on the convex portion 50. FIG. This makes it possible to vary the position at which the intermediate link portion A2 is restricted.

As described above, according to the twelfth embodiment, since the stopper STA3 having a mechanism for changing the position in which the intermediate link portion A2 is restricted in the opening direction is provided in the rotational direction, an external force is applied to the passive joint portion PA2. The state, that is, the posture when the intermediate link portion A2 is completely closed changes. Therefore, the grip completion posture of the robot hand changes, and various grip objects can be gripped with finger postures that facilitate gripping. This makes it possible to grip a wider variety of objects to be gripped with the same mechanism and configuration.

The configuration shown in the above embodiment shows an example of the content of the present disclosure, and can be combined with another known technology. It is also possible to omit or change the part.

1 robot, 2 robot control device, 5 arm, 10 robot hand, 20 base, 21, 21b finger pad, 22 rear surface, 23 base end, 24 tip, 25 protrusion, 26 grip, 27 friction member, 30 Robot fixing part, 40 covering member, 40a thin part, 40b slack, 50 convex part, 51 long hole, 52 pin, A first finger part, A1, B1 base end link part, A2, B2' middle link part, A3, A3', A3α, A3β, A3γ, B2, B3 Tip link part, B Second finger part, D0, DA1, DB1 Drive part (rotational drive part), G0 Transmission mechanism part, JT0 Rotational joint part, P0, PA2, PA3 , PB1, PB2, PA3α, PA3β, PA3γ　Passive joint part, Q　Floor surface, S0, SA1, SA2, SA3, SB1, SB2　Spring element, STA1, STA2, STA3, STB1　Stopper, W, W1, W2, W3　Grip target thing.

Claims

A robot hand that grips an object to be gripped,
a finger having a first finger and a second finger facing the first finger;
a base provided on an arm of the robot;
a drive unit connected to the base for rotationally driving at least one of the first finger and the second finger;
with
The first finger is
a first link portion connected to the base;
a second link portion connected to the first link portion;
a third link portion connected to the second link portion;
a first passive joint portion that rotatably supports the first link portion and the second link portion;
a second passive joint portion that rotatably supports the second link portion and the third link portion;
a first elastic body that holds the first link portion and the second link portion in a basic posture;
A robot hand comprising:
The robot hand according to claim 1, wherein the drive section rotates the first link section of the first finger section.
The second finger
a fourth link connected to the base;
a fifth link portion connected to the fourth link portion;
a third passive joint portion that rotatably supports the fourth link portion and the fifth link portion;
a second elastic body that holds the fourth link portion and the fifth link portion in a basic posture;
3. The robot hand according to claim 2, comprising:
The rigidity of the first elastic body is set so that the basic posture is a state in which the first link portion is closed from the horizontal and the second link portion is aligned with the direction of gravity. 3. The robot hand according to claim 2.
The robot hand according to claim 2 or 3, further comprising a first stopper that restricts rotation of at least the second link portion of the second link portion and the third link portion in an opening direction.
The robot hand according to any one of claims 2 to 4, wherein the third link portion includes a first finger pad that is thick on the base end side and tapered toward the tip end side.
The third link portion has a back portion and a finger pad,
The back surface portion has a plane parallel to the central axis of the second link portion,
5. The finger pad according to any one of claims 2 to 4, wherein the proximal side of the finger pad has a convex shape protruding toward the front side, and the tip side of the finger pad has a tapered shape. A robot hand described in one.
2. The third link portion has a protruding portion that extends above the second passive joint portion and protrudes rearward from the second passive joint portion in a posture that hangs down under its own weight. 5. The robot hand according to any one of 4 to 4.
A distal end side of the third link portion from the second passive joint portion is tapered,
The robot hand according to claim 8, wherein a base end portion of the third link portion on a tip end side from the second passive joint portion protrudes to the back surface side and the front surface side.
10. The apparatus according to any one of claims 2 to 9, further comprising a third elastic body having a rigidity lower than that of the first elastic body and holding the second link portion and the third link portion so as to assume the basic posture. A robot hand according to any one of the above.
a robot fixing part fixed to the arm of the robot;
a fourth passive joint portion that rotatably supports the robot fixing portion and the base;
a third elastic body that holds the robot fixing portion and the base in a basic posture;
The robot hand according to any one of claims 2 to 10, further comprising:
The first finger is
further comprising a second stopper that restricts rotation in the opening direction of the second link,
The second finger
a sixth link connected to the base;
a seventh link portion connected to the sixth link portion;
an eighth link portion connected to the seventh link portion;
a fifth passive joint portion that rotatably supports the sixth link portion and the seventh link portion;
a sixth passive joint portion that rotatably supports the seventh link portion and the eighth link portion;
a fourth elastic body that holds the sixth link portion and the seventh link portion in a basic posture;
a third stopper that restricts the rotation of the seventh link portion in the opening direction;
with
The first finger is
a seventh passive joint that rotatably supports the first link with respect to the base;
with
The second finger
an eighth passive joint that rotatably supports the sixth link with respect to the base;
with
The robot hand according to claim 1, wherein the driving section rotationally drives the seventh passive joint section and the eighth passive joint section.
The second finger
a ninth link connected to the base;
a tenth link portion connected to the ninth link portion;
a ninth passive joint portion that rotatably supports the ninth link portion and the tenth link portion;
a fifth elastic body that holds the ninth link portion and the tenth link portion in a basic posture;
with
The drive section rotationally drives the ninth link section of the second finger section,
The first finger is
a tenth passive joint that rotatably supports the first link with respect to the base;
a sixth elastic body that holds the base portion and the first link portion in a basic posture;
The robot hand according to claim 1, comprising:
The first finger is
further comprising a fourth stopper that restricts rotation in the opening direction of the second link,
The second finger
an eleventh link connected to the base;
a twelfth link portion connected to the eleventh link portion;
a thirteenth link portion connected to the twelfth link portion;
an eleventh passive joint portion that rotatably supports the eleventh link portion and the twelfth link portion;
a twelfth passive joint portion that rotatably supports the twelfth link portion and the thirteenth link portion;
a seventh elastic body that holds the eleventh link portion and the twelfth link portion in a basic posture;
a fifth stopper that restricts the rotation of the eleventh link portion in the opening direction;
with
The base rotatably supports the first link and the eleventh link so that the first link of the first finger and the eleventh link of the second finger intersect. Equipped with a rotating joint that
The first link portion has a first extension portion extending in a direction opposite to the second link portion,
The eleventh link portion has a second extension portion extending in a direction opposite to the twelfth link portion,
The drive section presses the first extension section and the second extension section to rotate the first link section and the eleventh link section with the rotary joint section as a fulcrum. The robot hand according to claim 1.
a plurality of the third link portions,
a plurality of the second passive joints,
the first finger pad is plural,
The robot hand according to claim 6, wherein the plurality of second passive joints are coaxially connected.
The second finger
a fourteenth link connected to the base;
a fifteenth link portion connected to the fourteenth link portion;
a 16th link portion connected to the 15th link portion;
a thirteenth passive joint portion that rotatably supports the fourteenth link portion and the fifteenth link portion;
a fourteenth passive joint portion that rotatably supports the fifteenth link portion and the sixteenth link portion;
an eighth elastic body that holds the fourteenth link portion and the fifteenth link portion in a basic posture;
with
The drive unit rotationally drives the fourteenth link portion of the second finger,
The sixteenth link portion has a second finger pad that is thick on the base end side and tapered toward the tip end side,
The sixteenth link portion is plural,
a plurality of the fourteenth passive joints,
the second finger pad is plural,
The robot hand according to claim 1, wherein the plurality of fourteenth passive joints are coaxially connected.
The first elastic body is an elastic covering member that covers at least a portion of the first link portion, a portion of the second link portion, and the first passive joint portion. A robot hand according to any one of claims 1 to 16.
The robot hand according to claim 17, wherein the covering member has slack on the outside of the first passive joint portion and has a thin portion on the inside of the first passive joint portion.
6. The robot hand according to claim 5, wherein the first stopper has a mechanism for varying the position at which the second link portion is restricted in the rotational direction.