WO2023105926A1

WO2023105926A1 - Movable joint structure and robot hand comprising movable joint structure

Info

Publication number: WO2023105926A1
Application number: PCT/JP2022/038499
Authority: WO
Inventors: 一晶田中
Original assignee: 国立大学法人京都工芸繊維大学
Priority date: 2021-12-06
Filing date: 2022-10-17
Publication date: 2023-06-15
Also published as: JPWO2023105926A1

Abstract

A movable joint structure comprises a metacarpal 1 and a proximal phalanx 2. The proximal phalanx 2 is capable of displacement to a posture between a bent posture and an extended posture by rotating about a rotation axis A1, and is capable of displacement to a posture between a closed posture and an opened postured by rotating about a rotation axis A2, which is in a direction intersecting the rotation axis A1. The movable joint structure is provided with a spring 81 that exerts a bending/extending-direction force spanning the metacarpal 1 and the proximal phalanx 2, and a spring 82 that exerts an opening/closing-direction force spanning the metacarpal 1 and the proximal phalanx 2. Furthermore, the movable joint structure comprises: a bending/extending-direction force exerting linear member that generates a force on the bending/extending-direction rotation posture side by exerting a withdrawal force on the metacarpal 1 side; and a force conversion member 5 that converts the withdrawal force on the bending/extending-direction force exerting linear member to a force that displaces the joint to an opening/closing-direction rotation posture.

Description

Movable structure of joints and robot hand with movable structure of the joints

The present invention relates to a joint such as a finger of a robot, in particular, a movable structure for a joint capable of rotating about two axes, and a robot hand equipped with a movable structure for the joint.

Equipment called manipulators and robot hands with articulated fingers (hereinafter collectively referred to as robot hands) have been developed and used at manufacturing sites. In particular, robot hands imitating human hands have been proposed for use in artificial hands and, in recent years, as remote communication tools.

Since the human hand can not only flex and extend each finger, but also open and close the fingers (separate/approach the fingers), a robot hand that mimics the human hand can be used for the above-mentioned applications. Such a movement is necessary when applying to For example, in the humanoid robot hand of Patent Document 1, two joints having one degree of freedom are arranged in the metacarpal so as to be orthogonal, and the respective joints are operated by different powers to perform flexion/extension of the metacarpal. and opening and closing operations.

In addition, in the five-finger type hand device of Patent Document 2, the MP joints can be rotated about two axes, and individual fluid pressure cylinders are connected to each of them to control the fluid pressure of each MP joint. flexion/extension operation and opening/closing operation.

JP-A-2003-117873 JP 2010-264546 A

With the techniques of

Patent Documents

1 and 2 described above, the joint can be freely rotated around two axes. However, since the rotation around each rotation axis is individually controlled in each case, the structure may become complicated and the size of the device may increase. It should be noted that although the purpose of each device is to reduce the size of the device, there is a possibility that a sufficient reduction in size cannot be achieved depending on the intended use.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a movable structure of a robot joint capable of controlling rotation about two axes with a simple configuration, and a robot using the movable structure of the joint. It is to provide a hand.

In order to solve the above problems, a joint movable structure including a first member and a second member according to the present invention is configured such that the second member rotates about a first rotation axis to assume a bent posture. It is displaceable to a position between the extended position and the closed position and the open position by rotating the second member about a second rotating shaft in a direction intersecting the first rotating shaft. One of the bending and stretching postures is the initial posture in the bending and stretching direction, the other is the rotating posture in the bending and stretching direction, and one of the closed posture and the open posture is the initial posture in the opening and closing direction. and the other is in an opening/closing direction rotation posture, and the first elastic body is provided across the first member and the second member to apply a bending and stretching direction force, which is a force toward the bending and stretching direction initial posture side, to the joint. and a second elastic body provided across the first member and the second member for applying an opening/closing direction force, which is a force toward the opening/closing direction initial posture side, to the joint, and a retraction toward the first member. a bending and stretching direction force acting linear member that acts on the joint to apply a force to the bending and stretching direction rotational posture side by applying a force to the joint; and a force conversion member that converts the force into a force for displacing it to the opening/closing direction rotational posture.

In this configuration, since the bending and stretching direction force and the opening and closing direction force act on the joint, the joint in a state where no external force acts is in the initial posture in the bending and stretching direction and the initial posture in the opening and closing direction. When force is applied to such a joint by a bending-stretching direction force application linear member, it is possible to displace the joint from the bending-stretching direction initial posture to the bending-stretching direction rotational posture. In addition, since the retracting force of the bending and stretching direction force acting linear member is converted by the force conversion member into a force that displaces the joint to the opening/closing direction rotation posture, the joint is displaced from the opening/closing direction initial posture to the opening/closing direction rotation posture. That is, in this configuration, the retracting force of the bending and stretching direction force acting linear member can be used to displace the posture about the first rotation axis and to displace the posture about the second rotation axis.

In one preferred embodiment of the joint movable structure according to the present invention, the initial posture in the bending and stretching direction is the stretching posture, the rotating posture in the bending and stretching direction is the bending posture, and the initial posture in the opening and closing direction is the posture. the opening and closing direction rotational posture is the open posture; the bending and stretching direction force application linear member is an extension linear member that applies a force to the joint in the extension posture side; A bending linear member is provided that causes the joint to generate a force toward the bending posture side by applying a withdrawal force toward the first member side.

In this configuration, since the extension direction force (force toward the extension posture side) by the first elastic body and the closing direction force (force toward the closed posture side) by the second elastic body act on the joint, external force is applied to the joint. Inactive joints are in an extended and closed position. Such a joint can be displaced from a state in which a bending force is applied by a bending linear member to a bent posture to an extended posture by an extension linear member. Further, when a retracting force is applied to the stretchable member, the retracting force is converted into an opening direction force (force toward the open posture side) by the force converting member. As a result, the joint can be displaced to the open posture (rotating posture in the opening/closing direction). In this way, with this configuration, the joint, which is in the bent and closed posture due to the retracting force of the bending linear member, can be displaced to the extended and open posture only by the retracting force of the extending linear member.

In one preferred embodiment of the joint movable structure according to the present invention, the initial posture in the bending and stretching direction is the posture in which the bending and stretching directions are rotated, and the initial posture in the opening and closing direction is the posture in which the bending and stretching directions are rotated. the opening and closing direction rotational posture is the open posture; the bending and stretching direction force application linear member is an extension linear member that applies a force to the joint in the extension posture side; The force in the bending and stretching direction of the first elastic body is smaller than the force in the opening and closing direction of the second elastic body.

In this configuration, since the bending direction force (force toward the bent posture side) and the closing direction force (force toward the closed posture side) by the second elastic body act on the joint, the external force is applied to the joint. Inactive joints are in a flexed and closed position. With respect to such a joint, the retraction force applied to the extension wire-shaped member becomes an extension direction force (force toward the extension posture side), and the joint can be displaced to the extension posture (bending and stretching direction rotation posture). Further, when a retracting force is applied to the stretchable member, the retracting force is converted into an opening direction force (force toward the open posture side) by the force conversion member. As a result, the joint can be displaced to the open posture (rotating posture in the opening/closing direction). Furthermore, since the bending and stretching direction force of the first elastic body is smaller than the opening and closing direction force of the second elastic body, the joint can be displaced to the open posture after starting to be displaced to the extended posture. Thus, with this configuration, it is possible to change the posture about the first rotation axis and the posture about the second rotation axis only by the retraction force of the stretchable member, and furthermore, , the order in which they start their displacement can also be controlled.

In one preferred embodiment of the joint movable structure according to the present invention, the initial posture in the bending and stretching direction is the stretching posture, the rotating posture in the bending and stretching direction is the bending posture, and the initial posture in the opening and closing direction is the posture. the opening and closing direction rotation posture is the closed posture; the bending and stretching direction force applying linear member is a bending linear member that applies a force to the joint in the bending posture side; The force in the opening/closing direction of the second elastic body is smaller than the force in the bending/stretching direction of the first elastic body.

In this configuration, since the extension direction force (force toward the extension posture side) by the first elastic body and the opening direction force (force toward the open posture side) by the second elastic body act on the joint, external force is applied to the joint. Inactive joints are in an extended and open position. When a retraction force is applied to the bent linear member for such a joint, the retraction force is converted into a closing direction force (a force toward the closed posture side) by the force conversion member. As a result, the joint can be displaced to the closed posture (rotating posture in the opening/closing direction). Further, the retracting force applied to the bent linear member becomes a force in the bending direction (force toward the bending posture), and the joint can be displaced to the bending posture (rotating posture in the bending and stretching direction). Furthermore, since the opening/closing direction force of the second elastic body is smaller than the bending/stretching direction force of the first elastic body, the joint can be displaced to the bent posture after starting to be displaced to the closed posture. Thus, with this configuration, it is possible to change the posture about the first rotation axis and the posture about the second rotation axis only by the retraction force of the bent linear member. , the order in which they start their displacement can also be controlled.

In one preferred embodiment of the joint movable structure according to the present invention, the initial posture in the bending and stretching direction is the stretching posture, the rotating posture in the bending and stretching direction is the bending posture, and the initial posture in the opening and closing direction is the posture. The open position is the open position, the opening/closing direction rotation position is the closed position, the bending/stretching direction force applying linear member is an expanding linear member that applies a force to the joint in the extending position side, and the second A bending linear member that exerts a force toward the bending posture side on the joint by applying a withdrawal force toward the first member side, wherein the bending and stretching direction force of the first elastic body is applied to the second elastic body. is smaller than the opening and closing direction force of

In this configuration, since the extension direction force (force toward the extension posture side) by the first elastic body and the opening direction force (force toward the open posture side) by the second elastic body act on the joint, external force is applied to the joint. Inactive joints are in an extended and open position. When a retraction force is applied to such a joint to the stretchable member, the retraction force is converted into a closing direction force (toward the closed posture side) by the force conversion member. As a result, the joint can be displaced to the closed posture (rotating posture in the opening/closing direction). When the joint is displaced from the bent and closed posture to the extended and opened posture, the force in the bending and stretching direction of the first elastic body is smaller than the force in the opening and closing direction of the second elastic body. After starting the displacement to the posture, it can be displaced to the extension posture. Thus, with this configuration, it is possible to change the posture about the first rotation axis and the posture about the second rotation axis only by the retraction force of the stretchable member, and furthermore, , the order in which they start their displacement can also be controlled.

In one preferred embodiment of the joint movable structure according to the present invention, the initial posture in the bending and stretching direction is the stretching posture, the rotating posture in the bending and stretching direction is the bending posture, and the initial posture in the opening and closing direction is the posture. The open position is the open position, the opening/closing direction rotation position is the closed position, the bending/stretching direction force application linear member is a bending linear member that applies a force to the joint in the bending position side, and The force in the bending and stretching direction of the first elastic body is smaller than the force in the opening and closing direction of the second elastic body.

In this configuration, since the extension direction force (force toward the extension posture side) by the first elastic body and the opening direction force (force toward the open posture side) by the second elastic body act on the joint, external force is applied to the joint. Inactive joints are in an extended and open position. When a retraction force is applied to such a joint to the bending linear member, the joint can be displaced to a bending posture (rotating posture in the bending and stretching directions). Further, the retracting force is converted into a closing direction force (a force toward the closed posture side) by a force converting member. As a result, the joint can be displaced to the closed posture (rotating posture in the opening/closing direction). Furthermore, since the bending and stretching direction force of the first elastic body is smaller than the opening and closing direction force of the second elastic body, the joint can be displaced to the closed posture after starting to be displaced to the bent posture. Thus, with this configuration, it is possible to change the posture about the first rotation axis and the posture about the second rotation axis only by the retraction force of the bent linear member. , the order in which they start their displacement can also be controlled.

In one of the preferred embodiments of the joint movable structure according to the present invention, the force conversion member is provided at the end of the second member on the first member side, and rotates around the second rotation axis. It is rotatable substantially integrally with the two members, and has an action point on which the retracting force of the bending and stretching direction force action linear member acts, and the action point is in the opening/closing direction rotational posture relative to the second pivot shaft. located on the side.

In this configuration, the position of the action point of the bending and stretching direction force action line member on which the withdrawal force acts is displaced toward the opening and closing direction rotation posture side of the second rotation shaft. The retracting force of the shaped member can be converted into a turning force to the opening/closing direction turning posture.

In one of the preferred embodiments of the joint movable structure according to the present invention, the force conversion member includes a guide surface that guides the bending and stretching direction force acting linear member, and the guide surface is located on the first member side. The point of action is the end of the guide surface on the side of the second member.

In this configuration, when a retracting force is applied to the bending and stretching direction force acting linear member bent at the front end (action point) of the guide surface, the opening/closing position displacement force acting linear member tends to deform linearly. The force can be converted into a turning force to the opening/closing direction turning posture.

Furthermore, the present invention also covers a robot hand having the above-described joint movable structure, and such a robot hand is a robot hand having a thumb structure and at least one finger structure. Further, the thumb structure has the joint movable structure according to

claim

5 or 6, the joint is a CM joint, and the second member is a metacarpal.

In the robot hand of this configuration, when the joint movable structure of claim 5 is used for the CM joint of the thumb structure, a retraction force is applied to the extension linear member of the thumb structure in the extended posture and the open posture. When actuated, the thumb structure assumes a closed position. As a result, the space for receiving the other's hand can be increased when the robot hand shakes the hand. Further, when the joint movable structure of claim 6 is used for the CM joint of the thumb structure, when the bending linear member is pulled, the CM joint of the thumb structure starts to be displaced to the bending posture and then to the closed posture. Displace. Since the movement of the CM joints is similar to the movement of handshake, the robot hand having this configuration can give a feeling of handshake with a human when handshake with a human.

FIG. 4 is a perspective view of fingers of a robot hand; 4 is an exploded perspective view of fingers of a robot hand; FIG. FIG. 10 is a plan view of the metacarpal bone and force transfer member; It is a perspective view of a force conversion member. FIG. 2 is a cross-sectional view taken along the line VV in FIG. 1; FIG. 4 is a plan view showing opening and closing motions of fingers in Examples 1 and 2; It is a side view showing the flexion extension operation|movement of the finger|toe in embodiment. FIG. 11 is a bottom view showing opening and closing motions of a finger in Example 3; It is (a) an upper perspective view and (b) a lower perspective view of the thumb in Example 4. FIG. FIG. 9B is a cross-sectional view taken along the line XX in FIG. 9A; FIG. 9B is a cross-sectional view taken along line XI-XI in FIG. 9(a); FIG. 9B is a cross-sectional view taken along line XII-XII in FIG. 9(a). It is a perspective view of a robot hand. FIG. 4 is a perspective view of a robot hand in the middle of a handshake action; FIG. 4 is a perspective view of a robot hand in the middle of a handshake action; FIG. 4 is a perspective view of a robot hand in a handshake state;

The movable structure of the joint according to the present invention will be described below using the drawings. FIG. 1 is an upper perspective view of a finger other than the thumb of a robot hand having a joint movable structure according to the present invention, for example, a right index finger. In addition, the top in this description means the back side of the hand. A finger F includes a metacarpal bone 1 (an example of the first member in the present invention), a proximal phalanx 2 (an example of the second member in the present invention), a middle phalanx 3 and a distal phalanx 4 . The metacarpal bone 1 and the proximal phalanx 2 are arranged adjacent to each other in the longitudinal direction and connected to form an MP joint 91 (corresponding to the joint in the present invention). In the MP joint 91, the proximal phalanx 2 is rotated with respect to the metacarpal 1 by a rotation axis A1 (an example of the first rotation axis in the present invention) and a rotation axis A2 (an example of the second rotation axis in the present invention). It is possible to rotate around two axes. In this embodiment, the rotation axis A1 and the rotation axis A2 are orthogonal. The proximal phalanx 2 and the middle phalanx 3 are connected to form a PIP joint 92 , and the middle phalanx 3 and the distal phalanx 4 are connected to form a DIP joint 93 . The PIP joint 92 and the DIP joint 93 are rotatable about the rotation axis A3 and the rotation axis A4, respectively.

In this finger F, the MP joint 91, the PIP joint 92, and the DIP joint 93 are rotated around the rotation axes A1, A3, and A4, respectively, thereby displacing each joint to a posture between an extended posture and a bent posture. is possible. Further, by rotating the MP joint 91 around the rotation axis A2, the MP joint 91, that is, the finger F can be displaced to a posture between the closed posture and the open posture. Here, the open posture/closed posture are postures in which the finger is separated from/approached to other fingers.

In the following description, a posture in which no external force other than a spring, which will be described later, is acting on the finger F is called an initial posture. In particular, the flexion/extension direction postures (one of the flexion posture and the extension posture) of the MP joint 91, the PIP joint 92, and the DIP joint 93 when no external force other than the springs is acting are referred to as the initial posture in the flexion/extension direction, and the initial posture in the flexion/extension direction. The posture displaced from (the other of the bending posture or the stretching posture) is referred to as the bending and stretching direction rotation posture, and the posture of the MP joint 91 in the opening and closing direction when no external force other than the spring acts (one of the open posture or the closed posture) is referred to as an opening/closing direction initial attitude, and an attitude displaced from the opening/closing direction initial attitude (the other of the opening attitude and the closing attitude) is referred to as an opening/closing direction rotation attitude. The finger F (MP joint 91) shown in FIG. 1 is in the opening-closing direction initial posture, and is displaced to the opening-closing direction rotation posture by rotating the proximal phalanx 2 counterclockwise around the rotation axis A2. . Also, the fingertip side is the front side, and the opposite side is the back side.

For example, in a robot hand having fingers F with such a configuration, if all joints of all fingers are in a bent posture and all fingers are in a closed posture, a "goo" shape can be obtained. Conversely, if all joints of all fingers are in the extended posture and all fingers are in the open posture, a "par" shape can be obtained. Note that, in the following description, that the finger F is in the extended or flexed posture means that all joints are in the extended or flexed posture, and that the finger F is in the open or closed posture means that the MP It means that the joint 91 is in an open posture or a closed posture.

Next, each member constituting the finger F will be described using the exploded perspective view of FIG. The metacarpal 1 is a substantially rectangular parallelepiped having two bent portions (see FIG. 3), and a groove 11 is formed at the front end of the side surface on the side of the initial posture in the opening/closing direction (the front side of the drawing).

Insertion passages

12 and 13 are formed from the front end surface to the rear end surface for inserting an extended linear member W1 and a bent linear member W2, which will be described later. As shown in FIG. 3, the front end surface of the metacarpal bone 1 is composed of a first front end surface 1a and a second front end surface 1b. The first front end surface 1a is a plane whose normal direction is the same as the axial direction of the finger F. As shown in FIG. On the other hand, the second front end face 1b is a plane inclined so that the end on the opening/closing direction rotational position side (the upper side in FIG. 3) is retreated rearward.

The proximal phalanx 2 is a longitudinally elongated plate-like member with a slight thickness in the width direction, and a front connecting piece 21 projecting forward is formed at the front end. A connection hole 21a is formed through the front connection piece 21 in the width direction, and a bearing (not shown) is fitted therein. On the other hand, a pair of

rear connection pieces

22, 22 projecting rearward are formed at the rear end of the proximal phalanx 2. As shown in FIG. A connection hole 22a is also formed through the rear connection piece 22 in the width direction. A space S is formed between the pair of

rear connection pieces

22 , 22 . A groove 2 a is formed in the front end of the upper surface of the proximal phalanx 2 .

The middle phalanx 3 is a plate-shaped member that is shorter than the proximal phalanx 2 and slightly thicker in the width direction, and has a connecting piece 31 that protrudes forward at the front end. A connection hole 31a is formed through the connection piece 31 in the width direction, and a bearing (not shown) is fitted therein. On the other hand, the rear end of the middle phalanx 3 is formed with a notch 3d into which the front connecting piece 21 of the proximal phalanx 2 is fitted. A connection hole 3c is formed through the middle phalanx 3 in the width direction in the portion where the cut 3d is formed.

Grooves

3a and 3b are formed in the front and rear ends of the upper surface of the middle phalanx 3, respectively.

The distal phalanx 4 is a plate-like member having a length similar to that of the middle phalanx 3 and having a slight thickness in the width direction. The rear end of the distal phalanx 4 is formed with a notch 4c into which the connection piece 31 of the middle phalanx 3 is fitted. A connection hole 4b is formed in the portion of the distal phalanx 4 where the cut 4c is formed. A groove 4 a is formed at the rear end of the upper surface of the distal phalanx 4 .

The force conversion member 5 is a member with a size that fits into the space S formed at the rear end of the proximal phalanx 2 . Specifically, as shown in FIGS. 3 and 4, a base portion 53, a first projecting portion 51 projecting from the base portion 53 toward the opening/closing direction initial posture side (lower side in FIG. and a second projecting portion 52 projecting toward the dynamic posture side (upper side in FIG. 3). Connection holes 51a and 52a are formed in the side surfaces of the first projecting portion 51 and the second projecting portion 52, respectively, and bearings (not shown) are fitted therein. A groove 51b is formed in the rear end side surface of the first projecting portion 51. As shown in FIG. On the other hand, a connection hole 5a is formed in the upper surface of the base portion 53. As shown in FIG.

The upper surface of the base portion 53 is higher than the upper surfaces of the first overhanging portion 51 and the second overhanging portion 52 to form a protruding portion 54 . A guide surface 54a is formed on the side surface of the protruding portion 54 on the opening/closing direction rotational posture side toward the rear from the intermediate position and is inclined toward the opening/closing direction initial posture side. The function of this guide surface 54a will be described later.

The rear end surface of the force conversion member 5 is composed of a first rear end surface 5b formed on the opening/closing direction initial posture side and a second rear end surface 5c formed on the opening/closing direction rotational posture side. The first rear end surface 5b is a plane having a normal line in a direction that coincides with the axial direction of the finger F, and faces the first front end surface 1a of the metacarpal bone 1 when the MP joint 91 is in the initial posture in the opening/closing direction. ing. On the other hand, the second rear end surface 5c is an arc-shaped surface in which the end portion on the opening/closing direction rotational posture side is retracted forward.

The connecting member 6 is a substantially plate-like member for connecting the metacarpal bone 1 and the force converting member 5, and has a connecting hole 6a extending vertically through the front end thereof, into which a bearing (not shown) is fitted. is Further,

screw holes

6b and 6c for screwing to the metacarpal bone 1 are formed on the rear end side.

A spring that applies a force to the finger F so that the MP joint 91, the PIP joint 92, and the DIP joint 93 assume the initial posture in the bending and stretching direction, and a spring that applies a force to cause the MP joint 91 to assume the initial posture in the opening/closing direction. and are provided as described later. In the following description, the forces that cause the joint to assume the extended and flexed postures are referred to as the extension direction force and the flexion direction force, and the forces that cause the MP joint 91 to assume the closed and open postures are the closed direction force and the open direction force. It is called directional force.

A spring 81 (an example of the first elastic body in the present invention) is provided in the space formed between the first projecting portion 51 of the force conversion member 5, the projecting portion 54, and the proximal phalanx 2. The spring 81 applies a force to the MP joint 91 so that it assumes an initial posture in the bending and stretching directions. On the other hand, a spring 83 (an example of a second elastic body in the present invention) is provided in a space formed between the second projecting portion 52 and the protruding portion 54 of the force conversion member 5 and the proximal phalanx 2 . The spring 83 applies force to the MP joint 91 so as to assume the initial posture in the opening/closing direction. A spring 82 (an example of a second elastic body in the present invention) is provided across the groove 11 of the metacarpal bone 1 and the groove 51b of the force conversion member 5 to apply force to the initial posture of the MP joint 91 in the opening/closing direction. I am making it work. In the present embodiment, the

springs

82 and 83 apply force to the MP joint 91 so as to set the initial posture in the opening/closing direction, but only one of them may be applied.

A spring 84 is provided across the groove 2a of the proximal phalanx 2 and the groove 3b of the middle phalanx 3, and exerts a force to bring the PIP joint 92 into the initial posture in the bending and stretching directions. A spring 85 is provided across the groove 3a of the middle phalanx 3 and the groove 4a of the distal phalanx 4, and exerts a force to bring the DIP joint 93 into the initial posture in the bending and stretching directions.

The posture of the finger F in this embodiment can be changed by the stretched linear member W1 and the bent linear member W2. As the stretched wire member W1 and the bent wire member W2, those having flexibility and durability are desirable, and for example, metal wires, PE lines, and the like can be used.

As shown in FIG. 5, the finger F in this embodiment passes through the extension linear member W1 and the bending linear member W2, so that the proximal phalanx 2 and the middle phalanx 3 are positioned on top of each other.

Insertion passages

2b and 3e and

lower insertion passages

2c and 3f are formed in the lower part. A stretchable member W1 is inserted through these

upper insertion passages

2b and 3e. The front end of the extension wire member W1 is fixed to the front side surface of the groove 4a of the distal phalanx 4. As shown in FIG. The rear end of the stretchable member W1 extends through the insertion passage 12 of the metacarpal bone 1 and is connected to an actuator (not shown). On the other hand, a bent linear member W2 is inserted through the

lower insertion passages

2c and 3f. The front end of the bent linear member W2 is fixed to the front surface of a recess formed in the lower portion of the distal phalanx 4. As shown in FIG. The rear end of the bent linear member W2 extends through the insertion passage 13 of the metacarpal bone 1 and is connected to an actuator (not shown). The stretchable member W1 passes inside the

springs

85 and 84 when passing through the

grooves

4a, 3a, 3b and 2a. By arranging the stretchable member W1 in this way, it is possible to protect the stretchable member W1 at the joint position and prevent sagging. 5, the metacarpal bone 1, the connecting member 6, and the

springs

84 and 85 are omitted.

Next, assembly of the finger F provided with such members will be described with reference to FIGS. 1 and 2. FIG. However, the assembly order can be changed as appropriate. First, the connection piece 31 of the middle phalanx 3 is inserted into the notch 4c of the distal phalanx 4 so that the axial centers of the connection hole 4b and the connection hole 31a are aligned, and the fixing shaft is inserted through the connection hole 31a and the connection hole 4b. is inserted. This allows the DIP joint 93 to be displaced between the flexion posture/extension posture.

Similarly, the front connection piece 21 of the proximal phalanx 2 is inserted into the notch 3d of the middle phalanx 3 so that the axial centers of the connection hole 3c and the connection hole 21a are aligned, and the connection hole 21a and the connection hole 3c are inserted. The fixed shaft is inserted through the This allows the PIP joint 92 to be displaced between the flexion/extension positions.

Next, the front end of the spring 82 is fixed near the front end of the groove 51 b of the force conversion member 5 . Then, the force conversion member 5 is inserted into the space S at the rear end of the proximal phalanx 2 so that the axial centers of the connection hole 22a and the connection holes 51a and 52a are aligned, and the connection hole 51a and the connection holes 22a, and A fixed shaft is inserted through each of the connection hole 52a and the connection hole 22a. This allows the MP joint 91 to be displaced between the flexion posture/extension posture. Then, as described above, the

springs

81, 83, 84, 85 are fixed.

Further, the connection member 6 is put over the force conversion member 5 so that the axial centers of the connection holes 6a and 5a are aligned, and a fixed shaft is inserted from the connection hole 6a to the connection hole 5a. Then, screws are inserted through the screw holes 6b and 6c of the fixing member 6 and screwed to the metacarpal bone 1.例文帳に追加Furthermore, the rear portion of the spring 82 is fitted into the groove 11 to fix the rear end. This allows the MP joint 91 to be displaced between the closed posture and the open posture.

The motion of the finger F in this embodiment will be described with reference to FIGS. In this embodiment, the finger F is the index finger of the right hand, and the initial posture of the finger F is the extended posture and the closed posture. That is, the opening/closing direction initial posture is the closed posture, and the opening/closing direction rotational posture is the open posture. Because of this initial posture, springs 81, 82, 84, and 85 are extension coil springs and spring 83 is a compression coil spring in this embodiment. That is, the

springs

81, 84, and 85 exert forces in the direction of extension so that the MP joint 91, the PIP joint 92, and the DIP joint 93 are in the extension posture, respectively, and the

springs

82 and 83 are closed so that the MP joint is in the closed posture. It exerts a directional force.

In this embodiment, the magnitudes of the forces in the direction of extension of the

springs

81, 84, and 85 are made different. Specifically, the extension direction force of the spring 85 is the smallest, and the extension direction force of the spring 81 is the largest. In addition, the magnitude of the extension direction force of each spring can be adjusted by the spring constant. For example, by varying the number of turns of each spring, it is possible to set the above-described relation between the magnitudes of the forces in the direction of extension.

In order to displace the finger F in the extended and closed posture to the extended and open posture (rotational posture in the opening/closing direction), the retracting force is not applied to the bent linear member W2. A retracting force is applied to the extension wire member W1 (corresponding to the bending and stretching direction force applying wire member in the present invention). The operation at that time is shown in FIG. 6A and 6B are plan views of the finger F in the extended and closed posture and the finger in the extended and open posture, respectively. As described above, since the finger F is the index finger of the right hand, the posture in which the finger F is separated from the middle finger on the right side, that is, the posture in which the proximal phalanx 2 is rotated counterclockwise in the figure with respect to the metacarpal bone 1 is the open posture. is. Note that the spring and the connecting member 6 are omitted in this figure.

As shown in FIG. 6( a ), the extension wire-like member W1 passes from the distal phalanx 4 through the middle phalanx 3 and the proximal phalanx 2 to the space S at the rear end of the proximal phalanx 2 . As shown in the figure, the position at which the stretchable member W1 exits into the space S is not the center in the width direction in a plan view, but the position displaced toward the open posture side (rotating posture side in the opening/closing direction, leftward in the drawing). It's becoming More specifically, the stretchable member W1 is led out into the space S at a position displaced from the rotation axis A2 to the open posture side, and then is attached to the side surface of the projecting portion 54 of the force conversion member 5 on the open posture side. It is guided rearward along the guide surface 54a and is further guided rearward and to the closed posture side along the guide surface 54a to be inserted through the insertion passage 12 of the metacarpal bone 1. As shown in FIG.

When an actuator (not shown) is actuated to apply a retraction force to the extension wire member W1 arranged in this way, a force in the direction of extension acts on the DIP joint 93, the PIP joint 92, and the MP joint 91. Since the is already in an extended posture, there is almost no change in posture and the extended posture is maintained. Further, when a retracting force is applied to the stretchable member W1, the stretchable member W1 bent in the space S tries to straighten. Therefore, the retracting force acting on the stretchable member W1 moves toward the open position with the front end 54b as a fulcrum at the front side of the front end 54b (an example of the point of action in the present invention) of the guide surface 54a. is converted into a rotational force of This rotational force is transmitted to the proximal phalanx 2 as an opening direction force, and when the opening direction force overcomes the closing direction force of the

springs

82 and 83, the proximal phalanx 2 rotates with respect to the metacarpal 1. The MP joint 91 rotates counterclockwise in the drawing about A2, and the MP joint 91 is displaced to the open position (FIG. 6(b)). Note that the force conversion member 5 rotates together with the proximal phalanx 2 . At this time, since the second rear end surface 5c of the force conversion member 5 is formed in an arc shape, the second rear end surface 5c contacts the front end surface of the metacarpal bone 1, thereby hindering the rotation of the force conversion member 5. can be avoided. Then, when the rear end surface of the proximal phalanx 2 contacts the second front end surface 1b of the metacarpal bone 1, the free rotation of the proximal phalanx 2 is restricted, and the MP joint 91 assumes the open posture.

On the other hand, in order to displace the finger F from the open posture to the closed posture, the retraction force of the stretchable member W1 should be relaxed. As a result, the force in the closing direction is applied to the MP joint 91 by the

springs

82 and 83, and the MP joint 91 is displaced to the closed posture.

Also, FIG. 7 shows the operation of displacing the finger F to the bending posture (rotating posture in the bending and stretching direction) in this embodiment. In addition, in this figure, the spring, the stretched wire member W1, and the bent wire member W2 are omitted. When bending the joint of the finger F, the extension linear member W1 is loosened, and an actuator (not shown) is operated to apply a retraction force to the bending linear member W2. As described above, since the

springs

81, 84, and 85 have different forces in the extension direction, it is possible to shift the timing at which the joints start to be displaced to the bent posture. Specifically, from the state in which all joints are in the extension posture (Fig. 7(a)), first, the DIP joint 93, to which the spring 85 with the smallest extension direction force is arranged, begins to bend (Fig. 7 (b)), and sequentially, the PIP joint 92 (FIG. 7(c)) and the MP joint 91 begin to bend (FIG. 7(d)). Note that when the finger F is bent, the MP joint 91 maintains the closed posture due to the closing force of the

springs

81 and 83 . Further, when the MP joint 91 is bent, the proximal phalanx 2 rotates about the rotation axis A1 with respect to the metacarpal 1, but the force conversion member 5 does not rotate about the rotation axis A1. .

When displacing all the joints from the bent posture to the extended posture, the retraction force of the bent linear member W2 should be relaxed. At this time, even if the retraction force is not applied to the extension wire member W1, each joint will be in the extension posture due to the extension direction force of the

springs

81, 84, and 85. After that, the MP joint 91 can be displaced to the open posture. Considering this, it is desirable to apply a retraction force to the stretchable member W1. When the finger F is displaced to the extended posture, it begins to extend sequentially from the MP joint 91 to the PIP joint 92 and then to the DIP joint 93, contrary to the displacement to the bent posture (FIG. 7(d)→(c)). → (b) → (a)). After all the joints are in the extended posture, if a retracting force is further applied to the wire W1, the MP joint 91 will be in the open posture as described above.

Thus, the finger F in this embodiment starts to extend in the order of the MP joint 91, the PIP joint 92, and the DIP joint 93 when shifting from the bent and closed posture to the extended and open posture. Then, after all the joints are displaced to the extended posture, the MP joint 91 shifts to the open posture. Further, when the finger F shifts from the extended and open posture to the bent and closed posture, the DIP joint 93, the PIP joint 92, and the MP joint 91 start bending in this order after the MP joint 91 shifts to the closed posture. can be made That is, the joints of the finger F in this embodiment can be made to operate in the same order as the human finger joints.

In this embodiment, such motions of the finger F are controlled by the stretchable wire member W1 and the bent wire member W2. When connected to the actuator of the mold and rotated in the first direction, a withdrawal force is generated in the extension linear member W1, and when rotated in the opposite direction to the first direction, a withdrawal force is generated in the bending linear member W2. is generated, the above operation can be controlled by one actuator.

In this embodiment, the initial posture of the finger F is a bent posture and a closed posture, so-called "goo". That is, the opening/closing direction initial posture is the closed posture, and the opening/closing direction rotational posture is the open posture. Because of this initial posture, springs 81, 83, 84, and 85 are compression coil springs and spring 82 is an extension coil spring in this embodiment. That is, the

springs

81, 84, and 85 exert bending direction forces so that the MP joint 91, the PIP joint 92, and the DIP joint 93 are in the bending posture, respectively, and the

springs

82 and 83 are closed so that the MP joint is in the closed posture. It exerts a directional force. Although the present embodiment also includes the bent linear member W2, the bent linear member W2 does not need to be provided because it plays an auxiliary role.

As in the first embodiment, the fingers F in this embodiment also have the bending direction force of the

springs

81, 84, 85 in order to define the order of starting the extension/bending of the MP joint 91, the PIP joint 92, and the DIP joint 93. differing in size. Specifically, the spring constants of the respective springs are set so that the force in the bending direction of the spring 85 is the largest and the force in the bending direction of the spring 81 is the smallest. In this embodiment, the relationship between the magnitude of the force in the bending direction of the spring 81 and the magnitude of the force in the closing direction of the

springs

82 and 83 is also defined. Specifically, the force in the closing direction of the

springs

82 and 83 is greater than the force in the bending direction of the spring 81 . Furthermore, the force in the closing direction of the

springs

82 and 83 is set larger than the force in the bending direction of the spring 85 .

The motion of the finger F in this embodiment will be explained using FIGS. First, as described above, the initial posture of the finger F in this embodiment is the bent posture and the closed posture (FIG. 7(d)). From this posture, the tensile force of the extension wire member W1 (corresponding to the bending and stretching direction force acting linear member in the present invention) is strengthened while loosening the tensile force of the bending wire member W2. Then, among the

springs

81, 84, 85, and 82, the force in the bending direction of the spring 81 is the smallest, so the MP joint 91 begins to extend first (FIG. 6(c)). Then, the PIP joint 92 and the DIP joint 93 provided with a spring having a small bending direction force start to extend sequentially, and the finger F assumes an extended posture (rotating posture in the bending and stretching direction) (FIG. 7(b)→FIG. 7( a), FIG. 6(a)). When the tensile force of the stretchable member W1 is further strengthened, the force in the closing direction of the

springs

82 and 83 is overcome, and the proximal phalanx 2 rotates about the rotation axis A2 by the action described in the first embodiment. It rotates clockwise, and the MP joint 91, that is, the finger F assumes an open posture (rotating posture in the opening/closing direction) (FIG. 6(b)).

Further, when displacing the finger F from the extended and open posture to the initial posture of the bent and closed posture, the retracting force of the extending linear member W1 is relaxed and the retracting force is applied to the bent linear member W2. As a result, each joint is displaced to the closed posture and the bent posture in the order opposite to that described above. It should be noted that, in this embodiment, the finger F is displaced to the initial posture by the action of each spring without exerting a withdrawal force on the bent linear member W2.

In this way, by setting the strength of the spring (spring constant) as described above, the finger F in this embodiment can define the rotation order of each joint in the same manner as in the first embodiment.

In this embodiment, the initial posture of the finger F is an extended posture and an open posture, so-called "par". That is, the opening/closing direction initial posture is the open posture, and the opening/closing direction rotational posture is the closed posture. Further, the configuration of the finger F in this embodiment differs from that in the first and second embodiments in the arrangement of the metacarpal bone 1 and the force conversion member 5 . Specifically, as shown in the bottom view of FIG. 8, in this embodiment, the metacarpal bone 1 and the force conversion member 5 are arranged upside down from the arrangement in the first and second embodiments. . That is, in this embodiment, the guide surface 54a is provided on the lower surface side. Furthermore, it differs from the first and second embodiments in that it is the bent linear member W2 that is guided by the guide surface 54a. Note that the connection member 6 may be provided on the lower side along with such a layout change, but in that case, it is necessary to have a shape that does not hinder the bending of the connection member 6MP joint.

In this embodiment, the

springs

82, 84, 85 are extension coil springs and the

springs

81, 83 are compression coil springs because of the configuration and initial posture described above. That is, the

springs

81, 84, and 85 exert force in the direction of extension so that the MP joint 91, the PIP joint 92, and the DIP joint 93 are in the extended posture, and the

springs

82 and 83 open the MP joint in the open posture. It exerts a directional force. Although the stretchable member W1 is also provided in this embodiment, the stretchable member W1 does not have to be provided because it plays an auxiliary role. Although the spring 81 is arranged on the lower surface side in this embodiment, it may be arranged on the upper surface side as in the first and second embodiments. In that case, the shape may be modified so that a space for accommodating the spring 81 is formed on the upper surface side of the force conversion member 5 . In this case, the spring 81 becomes a tension coil spring.

As shown in FIG. 8, a bending linear member W2 (corresponding to a bending and stretching direction force application linear member in the present invention) fixed to the lower portion near the front end of the distal phalanx 4 extends from the distal phalanx 4 to the middle phalanx 3 and It passes through the lower part of the proximal phalanx 2 and exits into the space S at the rear end of the proximal phalanx 2 . As shown in the figure, the exit position of the bent linear member W2 to the space S is not the center in the width direction in the bottom view, but the position displaced toward the closed posture side (rotating posture side in the opening/closing direction, leftward in the drawing). It's becoming More specifically, the bent linear member W2 is drawn out into the space S at a position displaced from the rotation axis A2 toward the closed posture, and then extends to the side surface of the projecting portion 54 of the force conversion member 5 on the closed posture side. It is guided rearward along the guide surface 54a and is further guided rearward and to the open posture side along the guide surface 54a to be inserted through the insertion passage 13 of the metacarpal bone 1. As shown in FIG.

Also in this embodiment, the relationship between the magnitudes of the forces of the springs is defined. Specifically, among the

springs

81, 84, and 85, the extension direction force of the spring 85 is set to be the smallest, and the extension direction force of the spring 81 is set to be the largest. Further, the magnitude of the force in the opening direction of the

springs

82 and 83 is set smaller than the magnitude of the force in the extension direction of the spring 81 . Further, the magnitude of the force in the opening direction of the

springs

82 and 83 is set smaller than the magnitude of the force in the extension direction of the spring 85 .

The motion of the finger F in this embodiment will be described with reference to FIGS. When changing from the initial posture (Figs. 7(a) and 8(a)) to the bending posture (rotating posture in the bending and stretching direction) and the closed posture (rotating posture in the opening and closing direction), the stretchable member W1 is loosened and the bending line A retracting force is applied to W2 by the like member. Then, force acts on the MP joint 91, the PIP joint 92, and the DIP joint 93 in the bending direction. Further, a force in the closing direction acts on the MP joint 91 by the same action as described in the first embodiment. As described above, since the force in the closing direction of the

springs

82 and 83 is the smallest, the MP joint 91 is displaced (rotated) to the closed position before the MP joint 91, the PIP joint 92, and the DIP joint 93 are bent. begins. At this time, the proximal phalanx 2 rotates counterclockwise in the figure together with the force conversion member 5 about the rotation axis A2. When the first rear end surface 5b of the proximal phalanx 2 abuts the second front end surface 1b of the metacarpal 1, the free rotation of the proximal phalanx 2 is restricted, and the MP joint 91 assumes a closed posture (Fig. 8(b)).

Further, when the retracting force of the bending linear member W2 is increased, the DIP joint 93 first begins to bend (FIG. 7(b)), and then the PIP joint 92 (FIG. 7 ( c)), the MP joint 91 begins to bend (FIG. 7(d)), and all the joints assume a bending posture.

When the retraction force of the extension linear member W1 is strengthened while weakening the retraction force of the bending linear member W2 from the state in which the finger F is in the bent and closed posture, the movement from the MP joint 91 to the PIP is performed opposite to the above operation. The joint 92 and the DIP joint 93 begin to extend in order (FIG. 7(d)→(c)→(b)→(a)), and finally the MP joint 91 is displaced to the open posture (FIG. 8(a) )). In this embodiment, the finger F is displaced to the initial posture by the action of each spring without exerting a withdrawal force on the stretchable member W1.

As described above, in the movable structure of the joint according to the present invention, the magnitude of the force of the elastic body (spring) that exerts the force so as to assume the initial posture in the bending and stretching directions, and the elastic body (spring) that exerts the force so as to assume the initial posture in the opening/closing direction By defining the relationship between the force of the spring and the magnitude of the force, it is possible to control the timing at which the joint starts to be displaced to the bending and stretching direction rotational posture and the timing to start the joint to be displaced to the opening and closing direction rotational posture. Further, by using the force conversion member 5 as described above, it is possible to control the rotation of the joint in two directions with a single linear member (wire).

9(a) and (b) are an upper perspective view and a lower perspective view of a right thumb F of a robot hand having a joint movable structure according to the present invention. The finger F includes a supporting bone 7 (an example of the first member in the present invention, corresponding to the great rhomboid bone of the human hand), a metacarpal bone 1 (an example of the second member in the present invention), a proximal phalanx 2 and a distal phalanx. 4. The supporting bone 7 and the metacarpal bone 1 are arranged adjacent to each other in the longitudinal direction and connected to form a CM joint 94 (corresponding to the joint in the present invention). In the CM joint 94, the metacarpal bone 1 rotates with respect to the supporting bone 7 along a rotation axis A5 (an example of the first rotation axis in the present invention) and a rotation axis A6 (an example of the second rotation axis in the present invention). It is possible to rotate around two axes. In addition, in this embodiment, the rotation axis A5 and the rotation axis A6 are perpendicular to each other. The metacarpal bone 1 and the proximal phalanx 2 are connected to form an MP joint 91 , and the proximal phalanx 2 and the distal phalanx 4 are connected to form an IP joint 95 . The MP joint 91 and the IP joint 95 can rotate about the rotation axis A1 and the rotation axis A7, respectively.

A spring 86 is provided on the side surface of the support bone 7 (left side surface in the drawing) to apply a force (opening/closing direction force) to the rear end of the metacarpal bone 1 . A spring 87U and a spring 87L are provided on the upper side and the lower side across the support bone 7 and the metacarpal bone 1. As shown in FIG. Similarly, upper and

lower springs

88U and 88L are provided across the metacarpal bone 1 and proximal phalanx 2, and upper and

lower springs

89U and 89L are provided across the proximal phalanx 2 and distal phalanx 4. It is The initial postures of the finger F in this embodiment are the open posture and the extended posture. That is, the opening/closing direction initial posture is the open posture, and the opening/closing direction rotational posture is the closed posture. The posture in which the metacarpal 1 rotates clockwise about the rotation axis A6 from the open posture of FIG. Therefore, the spring 86 is a tension coil spring that applies force to the metacarpal bone 1 toward the open posture side. In addition, since it is necessary to apply force in the direction of extension to CM joint 94, MP joint 91 and IP joint 95, springs 87U, 88U and 89U are extension coil springs, and springs 87L, 88L and 89L are compression coil springs. In this embodiment, springs are provided on the upper and lower surfaces of the CM joint 94, MP joint 91 and IP joint 95, but springs may be provided on the upper side or the lower side to apply a force in the extension direction.

FIG. 10 is a cross-sectional view taken along line XX in FIG. 9 near the CM joint 94. FIG. In this embodiment, a force conversion member 5 is provided between the supporting bone 7 and the metacarpal bone 1 . Although the shape of the force conversion member 5 in this embodiment is slightly different from that in the above-described embodiments, the rear end surface is similarly formed on the opening/closing direction initial posture side (lower side in the figure), and and a second rear end surface 5c formed on the opening/closing direction rotation attitude side (upper side in the drawing). Further, as in the above-described embodiment, the first rear end face 5b is a plane having a normal line in a direction coinciding with the axial direction of the finger F, and the second rear end face 5c is in a rotational posture in the opening/closing direction. The side ends are arcuate surfaces that recede forward.

When the finger F is displaced to the closed posture, that is, rotated clockwise about the rotation axis A6, the second rear end surface 5c of the force conversion member 5 abuts the second front end surface 7b of the supporting bone 7. contact, and further rotation is restricted. In this embodiment, the second front end surface 7b is a plane having a normal line in a direction coinciding with the axial direction of the finger F. In addition, the flat surface may be inclined so that the end portion on the opening/closing direction rotational posture side (the upper side in FIG. 10) is retracted rearward.

FIG. 11 is a cross-sectional view taken along line XI-XI in FIG. As shown in the figure, the force conversion member 5 has a projecting portion 54 formed on its upper side in the same manner as in the above-described embodiment. A guide surface 54a is formed on the side surface and is inclined rearward from the intermediate position toward the opening/closing direction initial posture side (open posture side). Also, the point that the front end portion 54b of the guide surface 54a functions as a point of action in the present invention is the same as in the above-described embodiment.

As shown in FIG. 11, the extension linear member W1 (corresponding to the bending and stretching direction force application linear member in the present invention) is arranged above the middle of the finger F, and the supporting bone 7 is in a slightly open posture (Fig. 11). middle left side), the slightly closed posture side (right side in the figure) of the guide surface 54a of the force conversion member 5, and the center of the metacarpal bone 1, the proximal phalanx 2, and the distal phalanx 4, and is fixed to the fingertip. ing. Therefore, when a retracting force is applied to the stretchable member W1 while the finger F is in the initial posture, the bent portion of the stretchable member W1 tends to straighten as described above. At this time, the stretchable member W1 abuts against the guide surface 54a of the force converting member 5, and the retracting force is converted into a clockwise rotating force about the rotating shaft A6. As a result, the metacarpal 1 rotates clockwise around the rotation axis A6, and the finger F is displaced to the closed posture.

FIG. 12 is a cross-sectional view taken along line XII-XII in FIG. As shown in the figure, the bent linear member W2 is arranged below the middle of the finger F, and the support bone 7 is slightly closer to the closed posture side (right side in the figure). ). That is, the bent linear member W2 passes through the closed position side of the rotation axis A6. Further, the bent linear member W2 passes through substantially the middle of the metacarpal bone 1, the proximal phalanx 2, and the distal phalanx 4, and is fixed to the fingertip. In this way, since the bent linear member W2 passes through the closed position side of the rotation axis A6, when a withdrawal force acts on the bent linear member W2, the bent portion of the bent linear member W2 straightens. When trying to rotate, a clockwise turning force is generated around the turning axis A6. As a result, the metacarpal 1 rotates clockwise around the rotation axis A6, and the finger F is displaced to the closed posture.

In this embodiment, the bent linear member W2 does not contact the guide surface 54a of the force conversion member 5, but a guide surface with which the bent linear member W2 contacts may be provided. In this case, the bending linear member W2 corresponds to the bending and stretching direction force acting linear member in the present invention. Even in this case, the same effect as described above can be obtained.

In this embodiment, when a withdrawal force is applied to the bending linear member W2, bending of the IP joint 95, bending of the MP joint 91, bending of the CM joint 94, and displacement of the CM joint 94 to the closed posture occur in order. The strength of each spring is set as follows. That is, when a retracting force is applied to the bending linear member W2, bending starts from the joint on the fingertip side, and then the finger F is displaced to the closed posture.

Here, an example of a robot hand using the finger F described above, particularly the finger F in Example 4 is shown. As shown in FIG. 13, the robot hand has a thumb F1 (corresponding to the thumb structure of the present invention), index finger F2, middle finger F3, ring finger F4 and little finger F5 (corresponding to the finger structure of the present invention). The thumb F1 is the same as the finger F shown in the fourth embodiment. On the other hand, the other fingers are slightly different in shape and construction from the above-described embodiment, but they are provided with a metacarpal bone 1, a proximal phalanx 2, a middle phalanx 3 and a distal phalanx 4, and an MP joint 91 and a PIP joint 92. and a DIP joint 93 are the same as in the above embodiment. It should be noted that the drawings in this embodiment show only the basic structure, and the springs and the like described in the above embodiments are omitted.

The index finger F2, middle finger F3, ring finger F4 and little finger F5 are connected to the support 100 so as to be able to bend/extend and open and close. For this connection, the same method as the connection between the metacarpal bone 1 and the proximal phalanx 2 in Examples 1 to 3 and the connection between the supporting bone 7 and the metacarpal bone 1 in Example 4 can be used. However, other methods can of course also be used. In this embodiment, this connection uses the same method as the connection between the metacarpal bone 1 and the proximal phalanx 2 in the third embodiment. That is, the initial postures of the index finger F2, the middle finger F3, the ring finger F4, and the little finger F5 are the extended and open posture, and by pulling the bent linear member W2 connected to each finger, each finger is displaced to the closed posture. Later, it is displaced to a bending posture. The direction of the closed posture of the index finger F2 and the middle finger F3 is clockwise in the drawing, and the direction of the closed posture of the ring finger F4 and the little finger F5 is counterclockwise in the drawing.

On the other hand, the thumb F1 is connected to the support 100 via a hinge H. Note that the thumb F1 is rotatable with respect to the hinge H about the rotation axis A8.

Next, we will explain the action of shaking hands using this robot hand. FIG. 13 shows the initial posture of the robot hand in this embodiment. Specifically, the thumb F1, the index finger F2, the middle finger F3, the ring finger F4 and the little finger F5 are in the extended posture and the open posture. With respect to the robot hand in this initial posture, the extended linear member W1 connected to the thumb F1 and the bent linear member W2 connected to the thumb F1, index finger F2, middle finger F3, ring finger F4 and little finger F5 are retracted. exert force. Then, as described above, the metacarpal bone 1 of the thumb F1 rotates clockwise about the rotation axis A6 with respect to the supporting bone 7, and the thumb F1 is displaced to the closed posture. On the other hand, the metacarpal bones 1 of the index finger F2 and the middle finger F3 rotate clockwise around the respective rotation axes A0 with respect to the support member 100, and the metacarpal bones 1 of the ring finger F4 and the little finger F5 rotate on the support member 100. On the other hand, they are rotated counterclockwise in the figure about the rotation axis A0, and the thumb F1, index finger F2, middle finger F3, and ring finger F4 are displaced to the closed posture. The robot hand in this state is shown in FIG. By displacing the thumb F1 to such a closed posture as an initial action for shaking hands, the space for the other party's hand to enter is increased, making it easier to grip the hand.

Then, the palm of the robot hand and the palm of the opponent's hand are brought together, and a retracting force is further applied to the bent linear member W2 connected to the index finger F2, middle finger F3, ring finger F4 and little finger F5. As a result, the MP joint 91, PIP joint 92 and DIP joint 93 of the index finger F2, the middle finger F3, the ring finger F4 and the little finger F5 are bent, and these fingers are displaced to the bent posture. In addition, the withdrawal force of the extension linear member W1 of the thumb F1 is released, and the withdrawal force is applied to the bending linear member W2. As a result, the thumb F1 first returns to the open posture, then the CM joint 94, the MP joint 91, and the IP joint 95 are bent and displaced to the bent posture. FIG. 15 shows the robot hand in this state.

Further, when a retracting force is applied to the bent linear member W2 of the thumb F1, as shown in FIG. 16, the thumb F1 rotates clockwise about the rotation axis A6 while maintaining the bent posture, and enters the closed posture. Displace. When a human handshakes strongly, the thumb moves in this way, so when shaking hands with the robot hand of the present embodiment, it is possible to feel more human-like.

[Another embodiment]
(1) In Examples 1 and 2, the extension wire member W1 was connected to the distal phalanx 4, but the extension wire member W1 may be connected to the proximal phalanx 2 or the middle phalanx 3. Similarly, in Example 3, the bent linear member W2 was connected to the distal phalanx 4, but the bent linear member W2 may be connected to the proximal phalanx 2 or the middle phalanx 3. In these cases, the joints (PIP joint 92 and/or DIP joint 93) positioned closer to the fingertip side than the connecting position of the extension wire member W1 and the bending wire member are springs 84 and/or 85 provided at the respective joints. can be extended/flexed by the action of In the first embodiment, when the extension wire member W1 is connected to the proximal phalanx 2 and the extension wire member W1 and the bending wire member W2 are connected to different actuators, the MP joint 91 can be in any posture in the opening/closing direction. However, the PIP joint 92 and the DIP joint 93 can be bent while the MP joint 91 is in the extended posture.

(2) In the above embodiments, the coil spring is used as the elastic body, but other springs such as leaf springs or elastic bodies other than springs may be used.

(3) In the above embodiment, the

springs

81, 84, 85 are provided above the finger F, but they may be provided below the finger F. Further, the spring 82 is provided on the side surface of the finger F on the opening/closing direction initial posture side, but may be provided on the side surface of the finger F on the opening/closing direction rotation posture side. Further, the

springs

82 and 83 are provided on the opening/closing direction initial attitude side and the opening/closing direction rotation attitude side with respect to the rotation axis A2, but these may be exchanged. However, when changing the arrangement position like these, it is necessary to change the compression coil spring to an extension coil spring and the extension coil spring to a compression coil spring.

(4) As long as the object of the present invention is achieved, the above embodiments can be modified as appropriate, and combinations of the embodiments are also possible.

The present invention can be applied to movable structures of robot joints, including joints at the base of fingers of robot hands. By applying such a movable structure to the joints at the base of the fingers of the robot, it is possible to move from a clenched state (Goo shape) to an open state (Pa shape) or vice versa with a simple structure. be able to. Such robotic hands can also be used, for example, in remote communication systems. In such a remote communication system, for example, a robot hand having a movable joint structure according to the present invention and a monitor are installed at a point 1 where a user 1 is, and a hand movement such as a data glove is installed at a point 2 where a user 2 is. Install sensitive sensors and cameras. The image captured by the camera at the point 2 is displayed on the monitor at the point 1, and the user 1 can see the user 2 visually. At point 2, when a sensor senses the user's hand gripping motion, the information is reflected in the motion of the robot hand at point 1, and the robot hand bends the joints of each finger F so as to grip the hand of user 1. Let By using such a remote communication system, it is possible to make a pseudo physical contact, and it is possible to enhance a sense of familiarity even though the two are physically separated from each other. As described above, in the remote communication system employing the joint movable structure according to the present invention, since the joints at the base of the fingers can be opened and closed, so-called lover-connection and handshakes are possible.

A1: Rotating shaft (first rotating shaft)
A2: Rotation shaft (second rotation shaft)
A5: Rotating shaft (first rotating shaft)
A6: Rotating shaft (second rotating shaft)
F: finger F1: thumb (thumb structure)
F2: index finger (finger structure)
F3: middle finger (finger structure)
F4: ring finger (finger structure)
F5: little finger (finger structure)
W1: Extension wire member (bending and stretching direction force acting wire member)
W2: Bending linear member (bending and stretching direction force acting linear member)
1: Metacarpal bone (first member, second member)
2: Proximal phalanx (second member)
3: middle phalanx
4: distal phalanx 5: force conversion member
54a: Guide surface 54b: Front end (point of action)
7: Supporting bone (first member)
8: Spring 81: Spring (first elastic body)
82: Spring (second elastic body)
83: Spring (second elastic body)
86: Spring (second elastic body)
87U: Spring (first elastic body)
87L: Spring (first elastic body)
91: MP joint (joint)
92: PIP joint 93: DIP joint 94: CM joint (joint)
95: IP joint

Claims

A joint movable structure comprising a first member and a second member,
By rotating the second member around the first rotating shaft, the second member can be displaced to a posture between a bending posture and an extended posture, and the second member can move in a direction intersecting the first rotating shaft. In a movable structure of a joint that can be displaced to a posture between a closed posture and an open posture by rotating around a second rotation axis,
One of the bending posture and the extension posture is defined as an initial posture in the bending and stretching direction, and the other is defined as a rotating posture in the bending and stretching direction. as a dynamic posture,
a first elastic body that is provided across the first member and the second member and applies a bending-stretching direction force, which is a force toward the bending-stretching direction initial posture side, to the joint;
a second elastic body that is provided across the first member and the second member and applies an opening/closing direction force, which is a force toward the opening/closing direction initial posture side, to the joint;
a bending and stretching direction force acting linear member that applies a force toward the bending and stretching direction rotational posture side to the joint by applying a retraction force toward the first member;
and a force conversion member that converts the retraction force applied to the bending and stretching direction force acting linear member into a force that displaces the joint to the opening and closing direction rotational posture.
The initial posture in the bending and stretching direction is the stretching posture,
The bending and stretching direction rotation posture is the bending posture,
the initial posture in the opening/closing direction is the closed posture;
The opening/closing direction rotation posture is the open posture,
The bending and stretching direction force application linear member is an extension linear member that exerts a force on the joint toward the extension posture side,
2. The joint movable structure according to claim 1, further comprising a bent linear member that exerts a force on the joint toward the bent position by applying a retraction force toward the first member.
The bending and stretching direction initial posture is the bending posture,
The bending and stretching direction rotation posture is the stretching posture,
the initial posture in the opening/closing direction is the closed posture;
The opening/closing direction rotation posture is the open posture,
The bending and stretching direction force application linear member is an extension linear member that exerts a force on the joint toward the extension posture side,
2. The joint movable structure according to claim 1, wherein the force in the bending and stretching direction of the first elastic body is smaller than the force in the opening and closing direction of the second elastic body.
The initial posture in the bending and stretching direction is the stretching posture,
The bending and stretching direction rotation posture is the bending posture,
The opening/closing direction initial posture is the open posture,
The opening/closing direction rotation posture is the closing posture,
The bending and stretching direction force applying linear member is a bending linear member that applies a force to the joint in the bending posture side,
2. The joint movable structure according to claim 1, wherein the force in the opening and closing direction of the second elastic body is smaller than the force in the bending and stretching direction of the first elastic body.
The initial posture in the bending and stretching direction is the stretching posture,
The bending and stretching direction rotation posture is the bending posture,
The opening/closing direction initial posture is the open posture,
The opening/closing direction rotation posture is the closing posture,
The bending and stretching direction force application linear member is an extension linear member that exerts a force on the joint toward the extension posture side,
a bending linear member that exerts a force toward the bending posture side on the joint by applying a retraction force toward the first member;
2. The joint movable structure according to claim 1, wherein the force in the bending and stretching direction of the first elastic body is smaller than the force in the opening and closing direction of the second elastic body.
The initial posture in the bending and stretching direction is the stretching posture,
The bending and stretching direction rotation posture is the bending posture,
The opening/closing direction initial posture is the open posture,
The opening/closing direction rotation posture is the closing posture,
The bending and stretching direction force applying linear member is a bending linear member that applies a force to the joint in the bending posture side,
2. The joint movable structure according to claim 1, wherein the force in the bending and stretching direction of the first elastic body is smaller than the force in the opening and closing direction of the second elastic body.
The force conversion member is
provided at the end of the second member on the side of the first member,
rotatable about the second rotating shaft substantially integrally with the second member;
comprising an action point on which the retraction force of the bending and stretching direction force action linear member acts,
The movable structure of the joint according to any one of claims 1 to 6, wherein the point of action is located on the side of the opening/closing direction rotation attitude with respect to the second rotation shaft.
the force conversion member has a guide surface that guides the linear force acting member in the bending and stretching directions,
the guide surface is inclined toward the opening/closing direction initial posture side toward the first member;
8. The joint movable structure according to claim 7, wherein the point of action is the end of the guide surface on the side of the second member.
A robotic hand comprising a thumb structure and at least one finger structure,
The thumb structure comprises the joint movable structure according to claim 5 or 6,
the joint is a CM joint;
The robot hand, wherein the second member is a metacarpal bone.