JP2022099041A - Band mechanism, robot hand and robot - Google Patents

Abstract

To provide a band mechanism that can achieve movement similar to human movement intuitively.SOLUTION: A hand mechanism comprises a palm part 9, a first finger 1 extending from a side portion of the palm part and a tip finger extending from a tip of the palm part. The first finger comprises a first link, pivotally supported on the palm part, which oscillates with a first axis in nearly parallel to an extending direction of the tip finger as a center, and a second link, pivotally supported on the first link, which oscillates with a second axis slightly inclined in a direction perpendicular to the first axis as a center.SELECTED DRAWING: Figure 1

Description

The present invention relates to a hand mechanism, for example, a robot hand mechanism arranged at the tip of a robot's arm or the like.

In recent years, research and development have been conducted on robot hands having a human-like structure for the purpose of realizing human-like movements.

In this type of hand, a finger corresponding to a human thumb is provided on the side of the palm, and a finger corresponding to the index finger or the ring finger is provided on the tip of the palm. For example, Patent Document 1 is provided with a thumb portion that is controlled so as to be swiveled or bent around the hand body portion with respect to the side surface of the hand body portion corresponding to the palm portion, with respect to the tip end portion of the hand body portion. Disclosed is a hand mechanism provided with an operating finger and an auxiliary finger controlled to be bent.

Japanese Unexamined Patent Publication No. 2017-164831

By the way, when trying to remotely control this kind of robot hand according to the movement of a human hand, or when trying to make a robot hand execute a human-like movement by a program, the mechanism of the robot hand is , It is preferable that it is an appropriate model of the complicated human hand mechanism. If this modeling is inappropriate, the movement of the robot hand may not intuitively correspond to the movement of the human hand, or the movement may feel strange.

However, in the conventional robot hand, the complicated human hand structure has been oversimplified, and the modeling of the human hand structure has been insufficient. As a result, it was difficult to operate the robot hand intuitively.

The present invention has been made in view of the above-mentioned technical background, and an object of the present invention is to provide a hand mechanism or the like capable of intuitively realizing a human-like operation.

The above-mentioned technical problem can be solved by a hand mechanism or the like having the following configuration.

That is, the hand mechanism according to the present invention is a hand mechanism including a palm portion, a first finger extending from the side portion of the palm portion, and a tip finger extending from the tip of the palm portion. The first finger is axially supported with respect to the palm portion and swings about a first axis substantially parallel to the extension direction of the tip finger, and an axis with respect to the first link. It is provided with a second link that is supported and swings around a second axis that is slightly tilted from a direction perpendicular to the first axis.

According to such a configuration, the first axis, which is the swing center axis of the first axis, and the second axis, which is the swing center axis of the second link, have a non-vertical positional relationship. As a result, it is possible to provide a hand mechanism that is similar to the structure of the first finger of a human, and thereby it is possible to provide a hand mechanism or the like that can intuitively realize a human-like operation.

The first axis may be further arranged parallel to the palm portion.

According to such a configuration, the first finger can be swiveled around the palm portion like a human.

A third link that is pivotally supported by the second link and swings about a third axis perpendicular to the second axis may be further provided.

According to such a configuration, since the swing center axis of the second link and the swing center axis of the third link are orthogonal to each other, it can operate in a human-like manner.

A fourth link that is pivotally supported by the third link and swings in conjunction with the third link may be further provided.

According to such a configuration, since the third link and the fourth link are interlocked with each other, it is possible to realize gripping that wraps the object.

The first finger may be configured to face the tip surface of the bent tip finger by bending.

According to such a configuration, the object can be gripped between the tip finger and the tip finger by bending the first child.

The first drive unit that drives the first link may be one that is supported by the palm portion.

According to such a configuration, since the drive unit is supported by the palm portion, the finger can be miniaturized or the finger can store another mechanism such as a sensor.

The second drive unit that drives the second link may be one that is supported by the first link.

According to such a configuration, since the drive unit is supported by the first link, the portion from the second link toward the tip can be miniaturized, or another mechanism such as a sensor can be stored in the portion. can.

The third drive unit for driving the third link and the fourth link may be one supported by the second link.

According to such a configuration, since the drive unit is supported by the second link, the portion from the third link toward the tip can be miniaturized, or another mechanism such as a sensor can be stored in the portion. can.

The first drive unit may be one that is driven by using a ball screw.

According to such a configuration, it is possible to output a high gripping force with high accuracy.

The second drive unit may be one that is driven by using a ball screw.

According to such a configuration, it is possible to output a high gripping force with high accuracy.

The third drive unit may be one that is driven by using a ball screw.

According to such a configuration, it is possible to output a high gripping force with high accuracy.

Each of the tip fingers may have a four-node link structure that bends or extends in conjunction with the tip finger drive unit arranged in the palm portion.

According to such a configuration, since the drive unit is provided in the palm portion, the tip finger can be miniaturized and other mechanisms such as a sensor can be stored in the tip finger.

The tip finger drive unit may be one that is driven by using a ball screw.

According to such a configuration, it is possible to output a high gripping force with high accuracy.

The tip finger may be three fingers including a second finger, a third finger and a fourth finger.

According to such a configuration, the object can be gripped so as to be wrapped with three fingers.

The rotation axis of the base portion of the third finger to the palm portion is sharp with the rotation axis of the base portion of the second finger to the palm portion and the rotation axis of the base portion of the fourth finger to the palm portion. It may be something that is doing.

According to such a configuration, the object can be grasped by wrapping the object with three fingers in a human-like manner.

The present invention can also be considered as a robot hand provided with the above-mentioned hand mechanism.

Furthermore, the present invention can also be thought of as a robot equipped with the above-mentioned hand mechanism.

According to the present invention, it is possible to provide a hand mechanism or the like that can intuitively realize a human-like operation.

FIG. 1 is a front view of the robot hand. FIG. 2 is a right side view of the robot hand. FIG. 3 is a front view of the robot hand in the closed state. FIG. 4 is a perspective view for explaining the configuration around the first joint portion. FIG. 5 is an explanatory diagram showing the state of rotation around the first rotation axis. FIG. 6 is an explanatory diagram showing the operating principle of the first drive unit. FIG. 7 is a schematic diagram showing the first drive unit in a simplified manner. FIG. 8 is a perspective view for explaining the configuration around the second joint portion. FIG. 9 is an explanatory diagram showing the state of rotation around the second rotation axis. FIG. 10 is an explanatory diagram showing the operating principle of the second drive unit. FIG. 11 is a schematic diagram showing a simplified second drive unit. FIG. 12 is an explanatory diagram regarding the arrangement of the first to third rotation axes. FIG. 13 is a perspective view for explaining the configuration of the third joint portion and the fourth joint portion. FIG. 14 is an explanatory diagram showing the state of rotation around the third rotation axis and the fourth rotation axis. FIG. 15 is an explanatory diagram showing the operating principle of the third drive unit. FIG. 16 is a schematic diagram showing a simplified third drive unit. FIG. 17 is a perspective view of the third finger of the robot hand. FIG. 18 is an explanatory diagram for explaining the operating principle of the third finger.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying figures.

(1. First Embodiment)
As a first embodiment, an example in which the present invention is applied to a robot hand 500 provided at the tip of a robot arm (not shown) will be described. The position where the robot hand 500 is attached is not limited, and it can be attached to various other devices, parts, and the like.

(1.1 Overall configuration and operation of the hand mechanism)
The overall configuration of the robot hand 500 will be described with reference to FIGS. 1 and 2. FIG. 1 is a front view of the robot hand 500 in a completely open state, and FIG. 2 is a right side view of the robot hand 500 in the same state. The open state means a state in which all the joints provided in the robot hand 500 are in the extended state. On the contrary, the closed state means a state in which some or all the joints provided in the robot hand 500 are bent.

As is clear from FIGS. 1 and 2, the robot hand 500 is mainly provided with a palm portion 9 having a substantially rectangular parallelepiped shape. From the right side surface of the palm portion 9, the first finger 1 corresponding to the first finger (thumb) of the human hand extends. From the upper surface or the tip of the palm portion 9, in order from the side of the first finger 1, it corresponds to the second finger 6 corresponding to the second finger (indicator) of the human hand and the third finger (middle finger) of the human hand. The third finger 7 and the fourth finger 8 corresponding to the fourth finger (medicine finger) of the human hand extend.

An instep cover 91 that covers the range from the entire instep to the side surface is attached to the back side of the palm portion 9, that is, the instep side of the robot hand 500. Further, on the front side of the palm portion 9, a palm portion cover 92 having a substantially keyhole shape, which is used for connecting to the tip end portion of an arm (not shown) and covers almost the entire palm portion, is provided.

The first finger 1 is configured by connecting the first link 111, the second link 112, the third link 113, and the fourth link 114 in order so as to extend from the side portion of the palm portion 9. It should be noted that the first link 111 and the second link 112 are not shown in the figure because they are covered by the first finger cover 199.

Further, the first finger 1 is in order from the palm portion 9 side toward the tip of the finger, the first joint portion 121 (corresponding to the so-called CM joint), the second joint portion 122, and the third joint portion 123 (so-called MP joint). Correspondingly), and has four joints of the fourth joint 124. Among them, the three joints of the first joint portion 121, the second joint portion 122, and the third joint portion 123 have the first rotation axis 101, the second rotation axis 102, and the third rotation axis 103, respectively. It actively rotates as a center, and the remaining fourth joint 124 passively rotates. That is, these structures enable operations such as bending a finger to grip an object.

The second finger 6 is configured by connecting the first link 611, the second link 612, and the third link 613 in order so as to extend from the tip of the palm portion 9.

Further, the second finger 6 has three joint portions, that is, the first joint portion 621 (corresponding to the so-called MP joint), the second joint portion 622, and the third joint portion 623, in order from the palm portion 9 side toward the tip of the finger. It is equipped with. Among them, the first joint portion 621 actively rotates around the first rotation shaft 601 and the remaining second joint portion 622 and the third joint portion 623 passively rotate. That is, these structures enable operations such as bending a finger to grip an object.

The third finger 7 is configured by connecting the first link 711, the second link 712, and the third link 713 in order so as to extend from the tip of the palm portion 9.

Further, the third finger 7 has three joints, that is, the first joint 721 (corresponding to the so-called MP joint), the second joint 722, and the third joint 723, in order from the palm 9 side toward the tip of the finger. It is equipped with. Among them, the first joint portion 721 actively rotates around the first rotation shaft 701, and the remaining second joint portion 722 and the third joint portion 723 passively rotate. That is, these structures enable operations such as bending a finger to grip an object.

The fourth finger 8 is configured by connecting the first link 811, the second link 812, and the third link 813 in order so as to extend from the tip of the palm portion 9.

Further, the fourth finger 8 has three joints, that is, the first joint 821 (corresponding to the so-called MP joint), the second joint 822, and the third joint 823, in order from the palm 9 side toward the tip of the finger. It is equipped with. Among them, the first joint portion 821 actively rotates around the first rotation shaft 801 and the remaining second joint portion 822 and the third joint portion 823 passively rotate. That is, these structures enable operations such as bending a finger to grip an object.

As is clear from the figure, the first rotation shaft 601 of the second finger 6, the first rotation shaft 701 of the third finger 7, and the first of the fourth fingers 8 provided near the tip of the palm portion 9. The rotating shafts 801 are not parallel to each other but have sharp angles to each other. That is, in the figure, although the first rotation axis 701 of the third finger 7 is parallel to the surface on the base side of the palm portion 9, the first rotation axis 601 of the second fingers 6 on the left and right thereof And the first rotation axis 801 of the fourth finger 8 are arranged evenly on the left and right sides with a slight inclination toward the side.

According to such a configuration, since each finger is bent toward the center of the palm portion 9, the object can be gripped in a human-like manner.

The robot hand 500 provided with the above joints and links can be opened and closed by rotating the joints.

FIG. 3 is a front view of the robot hand 500 in a completely closed state. As shown in the figure, by bending the first finger 1, the second finger 6, the third finger 7, and the fourth finger 8, the fingertips can be brought close to each other so as to grip the desired object.

In the figure, the tip of the first finger 1 is drawn so as to be substantially perpendicular to the tip of the second finger 6, the tip of the third finger 7, and the tip of the fourth finger 8. By rotating the second joint portion 122 of the finger 1, the tip of the first finger 1 is made to face each finger, that is, the tip of the second finger 6, the tip of the third finger 7, and the tip of the fourth finger 8. be able to.

With such a configuration, it is possible to realize a skillful operation such as pinching an object with a fingertip.

(1.2 Configuration and operation of first finger 1)
Hereinafter, the configuration and operation of the first finger 1 will be described in detail for each joint.

(First joint)
First, with reference to FIGS. 4 to 7, the configuration and operation of the first joint portion 121 of the first finger 1 will be described in detail.

FIG. 4 is a perspective view for explaining the configuration around the first joint portion 121. In the figure, for the sake of explanation, covers such as the instep cover 91 and the first finger cover 199, and other fingers and the like are not shown.

As is clear from the figure, a frame member 901 having a first drive shaft 131 as one side is provided at substantially the center of the palm portion 9. As a result, the first finger 1 is supported by the palm portion 9. The first drive shaft 131 brings the first rotation shaft 101.

A substantially cylindrical first servomotor 135 is arranged in the center of the frame member 901, and its output rotation axis protrudes from a hole provided on the left side surface of the frame member 901. A small-diameter first spur gear 136 is attached to the tip of the protruding output rotating shaft.

Immediately below the first servomotor 135, a first screw shaft 138 constituting a ball screw is arranged in parallel with the longitudinal direction of the first servomotor 135. One end of the first screw shaft 138 is pivotally supported together with one end of the first servomotor 135, while the other end protrudes from the hole on the left side surface. Further, a second spur gear 137 having a relatively large diameter is attached to the end of the protruding first screw shaft 138 so as to mesh with the first spur gear 136 having a small diameter.

A first nut member 139 is slidably attached to the first screw shaft 138 so as to form a ball screw. As will be described later, the first nut member 139 is connected to the first link 111 via the first transmission link 140 that transmits the driving force.

A series of members from the first servomotor 135 to the first transmission link 140 may be referred to as a first drive unit.

In this way, the first drive unit that rotates the first joint portion 121 is supported by the palm portion 9. As a result, it is possible to reduce the size of the first finger 1 and secure a space for storing a mechanism such as a sensor in the first finger 1.

The first link 111 is pivotally supported so as to rotate about the first drive shaft 131, that is, the first rotation shaft 101, and freely rotates by receiving a driving force from the first servomotor 135. An absolute encoder 132 for detecting the rotation angle of the first drive shaft 131 is arranged at the upper end of the first drive shaft 131.

FIG. 5 is an explanatory diagram showing the state of rotation around the first rotation axis 101. FIG. 5A shows the state of the robot hand 500 when the first link is at the position of 45 °, and FIG. 5B shows the state of the robot hand when the first link is at the position of 90 °. It shows the state of 500. In the figure, the angle of the first link 111 when it is in a completely open state is set to 0 °.

Subsequently, the driving principle of the first link 111 will be described with reference to FIGS. 6 and 7. FIG. 6 is an explanatory diagram showing the operating principle of the first drive unit.

As is clear from FIG. 6, when the first servomotor 135 is driven, the first spur gear 136 rotates. This rotation is transmitted to the first screw shaft 138 via the second spur gear 137, and the first screw shaft 138 rotates in conjunction with the first screw shaft 138.

When the first screw shaft 138 rotates, the first nut member 139 translates along the screw shaft 138 according to the rotation. This translation is transmitted to the connected first transmission link 140 to translate the first transmission link 140 in a direction parallel to the first screw axis.

At this time, the first transmission link 140 is pivotally supported with respect to the first nut member 139 via the first shaft member 141 so as to be slidable in a direction perpendicular to the first screw shaft (translation). Restraint). As a result, the first transmission link 140 also moves in the direction perpendicular to the first screw shaft 138 in accordance with the translational motion.

Since the first transmission link 140 that moves two-dimensionally is rotatably connected to the first link 111 via the second shaft member, the first link connects the first drive shaft 131. It will rotate as the center.

As described above, according to the configuration in which the driving force is generated by using the ball screw, high accuracy and gripping force can be realized.

FIG. 7 is a schematic diagram showing the first drive unit in a simplified manner. It should be noted that FIG. 7 is only a schematic diagram for explaining the principle and does not necessarily match the shapes and the like of the parts constituting the actual robot hand 500.

As is clear from the figure, when the first nut member 139 translates on the first screw shaft 138, the first transmission link 140 translates accordingly. The force from the first transmission link 140 is transmitted to the end of the first link 111, and rotation around the first drive shaft 131 is realized in the first link 111.

That is, with the above configuration, the first joint portion 121 of the first finger 1 rotates (turns) around an axis parallel to or substantially parallel to the extending direction of the second finger 6, the third finger 7, and the fourth finger 8. ) Is configured to be possible.

(Second joint)
Next, with reference to FIGS. 8 to 12, the configuration and operation of the second joint portion 122 will be described in detail.

FIG. 8 is a perspective view for explaining the configuration around the second joint portion 122.

As is clear from the figure, the first link 111 is further connected to the second link 112 in a manner that allows it to swing around the second rotation shaft 102.

It should be noted here that the second rotation axis 102 is not perpendicular to the first rotation axis 101, but is slightly tilted toward the finger side other than the vertical axis, that is, has an acute angle.

According to such a configuration, it is possible to provide a hand mechanism or the like that can intuitively realize a human-like operation.

A second servomotor 152 (not shown) is arranged inside the vicinity of the second rotation shaft 102 on the proximal end side of the second link 112, and its output shaft protrudes from the lower side in the figure. A small-diameter third spur gear 153 is attached to the tip of the protruding output shaft.

The third spur gear 153 meshes with the fourth spur gear 154 having a relatively large diameter and transmits a rotational force. The fourth spur gear 154 is connected to the second screw shaft 151 constituting the ball screw, and rotates the second screw shaft 151 in conjunction with the second screw shaft 151.

When the second screw shaft 151 rotates, the second nut member 155 translates along the second screw shaft 151. As will be described later, the movement of the second nut member 155 realizes the swing of the second link 112 about the second rotation shaft 102.

An absolute encoder 155 for detecting the swing angle is provided near the center of the second link 112.

A series of members that cause the swing from the second servomotor 152 to the second link 112 may be referred to as a second drive unit.

As described above, since the second drive unit that rotates the second joint portion 122 is supported by the first link 111, the swing function of the second joint portion can be integrated in the first finger 1. ..

FIG. 9 is an explanatory diagram showing the state of rotation around the second rotation axis 102. FIG. 9A shows the state of the robot hand 500 when the first finger 1 is closest to the second finger 6, and FIG. 9B shows the state of the robot hand 500 when the first finger 1 is from the second finger 6. It shows the state of the robot hand 500 when it is in the farthest position.

Subsequently, the swing principle of the second link 112 will be described with reference to FIGS. 10 and 11. FIG. 10 is an explanatory diagram showing the operating principle of the second drive unit.

As is clear from FIG. 10, when the second servomotor 152 (not shown) is driven, the small diameter third spur gear 153 rotates. As for the rotation of the third spur gear 153, the fourth spur gear 154 having a relatively large diameter rotates.

When the fourth spur gear 154 rotates, the second screw shaft 151, which is the central axis thereof, rotates.

When the second screw shaft 151 rotates, a substantially U-shaped or substantially U-shaped second nut member 155 translates along the second screw shaft 151.

A second transmission link 156 having a shaft portion supported by the open end and having the other end pivotally supported by the rotation indicating member 157 with respect to the second link 112 is attached to the open end of the second nut member 155. ing. The shaft portion of the second transmission link 156 slides in the axial direction with the translational motion of the second nut member 155.

According to such a configuration, since the second transmission link 156 is supported by the second link 112, the second link 112, the third link 113, and the second link 113 are accompanied by the translational motion of the second nut member 155. The four links 114 swing integrally around the second rotation shaft 102.

Further, according to the configuration in which the driving force is generated by using the ball screw, high accuracy and gripping force can be realized.

FIG. 11 is a schematic diagram showing a simplified second drive unit. It should be noted that the figure is only a schematic diagram for explaining the principle and does not necessarily match the shape of the parts constituting the actual robot hand 500.

As is clear from the figure, one end of the second link 112 is connected to the first link 111 so as to swing around the second rotation shaft 102. Further, the second screw shaft 151 constituting the ball screw is rotationally supported with respect to the first link.

In this state, when the second screw shaft 151 rotates, the second nut shaft member 155 translates along the shaft.

Further, one end of the second transmission link 156 is translated and restrained by the second nut shaft member 155, and the other end of the other end is rotatably supported by the second link 112. Therefore, when the second nut shaft member 155 moves, the second transmission link 156 translates in the direction of the arrow in the drawing on the second nut shaft member 155 days, whereby the second link moves to the second rotation shaft. It swings around 102.

FIG. 12 is an explanatory diagram of the arrangement of the first to third rotation axes 101 to 103 when the robot hand 500 in the open state is observed from the right side surface. As is clear from the figure, the first rotation axis 101 and the second rotation axis 102 are not orthogonal to each other, and are arranged so as to be slightly tilted with respect to the tip end side of the palm portion 9 so as to form θ (<90 °). .. Such a structure is similar to the structure of the human hand. That is, even in a human hand, the surface forming the belly of the tip of the first finger (thumb) is arranged so as to be slightly inclined to the tip side rather than parallel to the palm portion in the open state. Further, the second rotation shaft 102 and the third rotation shaft 103 are arranged so as to be orthogonal to each other.

According to such a configuration, it is possible to provide a hand mechanism or the like that can intuitively realize a human-like operation.

(Third joint and fourth joint)
Next, with reference to FIGS. 13 to 16, the configuration and operation of the third joint portion 122 and the fourth joint portion will be described in detail.

FIG. 13 is a perspective view for explaining the configuration of the third joint portion 123 and the fourth joint portion 124.

As is clear from the figure, on the instep side of the second link 112, a substantially cylindrical third servomotor 161 is arranged substantially horizontally with the longitudinal direction of the second link 112. The lower end of the third servomotor 161 is supported by a predetermined support housing, and a small-diameter fifth spur gear 162 attached to the output shaft of the third servomotor 161 projects from the support housing. The fifth spur gear 162 meshes with the sixth spur gear 163 having a relatively large diameter.

The sixth spur gear 163 is coupled to a third screw shaft 164 (not shown) which forms a part of a ball screw at its center (see FIG. 15). A third nut member 175 (not shown) is connected to the third screw shaft 164 (see FIG. 15), and the third nut member 175 slides in the axial direction of the third screw shaft 164 via a bolt 176. It is linked to a possible third transmission link 165.

The third transmission link 165 is connected to one end of the U-shaped transmission link 171 via the first connection shaft 167. The U-shaped transmission link 171 is supported by the second connecting shaft 169 in the middle thereof, and is connected to the fourth joint portion 124 by the fourth connecting shaft 177 through the inside of the third link 113 and the fourth link 114. ing.

Further, the base of the third link 113 is swingably connected to the second link 112 via the third connecting shaft 170. Further, the tip of the third link 113 is connected to the fourth link 114 via the fifth connecting shaft 178.

A series of drive systems from the third servomotor 161 to the fourth connecting shaft 177 may be hereinafter referred to as a third drive unit.

With the above configuration, the bending motion of the third joint portion 123 and the fourth joint portion 124 is realized.

FIG. 14 is an explanatory diagram showing the state of rotation around the third rotating shaft 103 and the fourth rotating shaft 104. FIG. 14A shows the robot hand 500 in the open state, and FIG. 14B shows the robot hand 500 in the closed state only in the third joint portion 123 and the fourth joint portion 124.

Subsequently, the swing principle of the third link 113 and the fourth link 114 will be described with reference to FIGS. 15 and 16. FIG. 15 is an explanatory diagram showing the operating principle of the third drive unit.

As is clear from FIG. 15A, in the state where the first finger 1 is extended, the third screw shaft 164 is arranged substantially parallel to the longitudinal direction of the second link 112. A third nut member 175 is attached to the third screw shaft 163 so as to form a ball screw, and a third transmission link 165 is connected to the nut member 175 via a bolt 176. Further, the housing supporting the third screw shaft 164 is rotatably connected to the second link 112 via the fifth rotation shaft 174.

In this state, when the third servomotor 161 is driven, the fifth spur gear 162 and the sixth spur gear 163 rotate, and the third screw shaft 164 is rotated. As a result, the third nut member 175 translates along the third screw shaft.

FIG. 15B shows a state in which the third nut member 175 is moved by a predetermined amount due to the rotation of the third screw shaft 164. As is clear from the figure, the movement of the third nut member 175 causes an operation of pushing up the third transmission link 165 from below. At this time, the third screw shaft 164 and the like rotate around the sixth rotation shaft 174.

When the third transmission link 165 is pushed up from below by the third nut member 175, one end of the U-shaped transmission link 171 is pushed up upward. At this time, the U-shaped transmission link 171 is pivotally supported to the second link 112 by the second connecting shaft 169 on the way. Therefore, the other end of the U-shaped transmission link 171 will be pushed down. Since the other end of the pushed down U-shaped transmission link 171 is connected to the fourth link 114 by the fourth connecting shaft 177, bending at the fourth joint portion 124 occurs.

Further, when the U-shaped transmission link 171 rotates about the second connecting shaft 169, the third link 113 swings around the third connecting shaft 170 so as to be driven by the fourth link 114. That is, bending occurs at the third joint portion 123.

FIG. 15 (c) shows a state in which the third nut member 175 is further raised with respect to the third screw shaft 164 from the state of FIG. 15 (b). In the state of the figure, the third nut member 175 is arranged at the upper limit position of the third screw shaft 164. Further, the third transmission link 165 is further pushed upward, and the third screw shaft 164 and the like are rotated so as to be further tilted from the vertical direction about the sixth rotation shaft 174.

By raising the transmission link 165, one end of the U-shaped transmission link 171 is further pushed up, and the other end of the U-shaped transmission link 171 is further pushed down. As a result, the fourth joint is further bent. Along with this, the third link 113 further swings around the third connecting shaft 170. That is, bending occurs at the third joint portion 123.

As described above, according to the configuration in which the driving force is generated by using the ball screw, high accuracy and gripping force can be realized.

FIG. 16 is a schematic diagram showing a simplified third drive unit. It should be noted that the figure is only a schematic diagram for explaining the principle and does not necessarily match the shape of the parts constituting the actual robot hand 500.

As is clear from the figure, a third screw shaft 164 is pivotally supported by the second link 112, and the third nut member 175 translates up and down along the third screw shaft 164. The third nut member 175 is connected to the lower end of the third transmission link 165, and the third transmission link 165 moves up and down together with the third nut member 175.

The upper end of the third transmission link 165 is rotatably connected to one end of the U-shaped transmission link 171, and the vicinity of the center of the U-shaped transmission link 171 is swingably supported with respect to the second link 112. Therefore, when one end of the third transmission link 165 is pushed up, the other end is pushed down.

Along with this pushing down, the fourth link 114 rotatably connected to the third connecting shaft 177 is bent toward the palm side. Further, with this bending, the third link 113 also swings toward the palm side around the third connecting shaft 170.

According to such a configuration, the third drive system is supported by the second link 112, and one drive system drives two joints of the third joint 113 and the fourth joint 114. Therefore, the internal configurations of the third link 113 and the fourth link 114 can be simplified. As a result, the fingertip can be miniaturized, and a space for attaching the sensor to the fingertip can be provided.

Further, even in a human hand, the third joint portion 113 and the fourth joint portion are bent so as to be interlocked with each other, so that a natural bending motion can be realized. That is, it is possible to provide a hand mechanism or the like that can intuitively realize a human-like operation.

(1.3 Composition and operation of fingers other than the first finger 1)
Next, with reference to FIGS. 17 and 18, the configurations and operations of fingers other than the first finger 1, that is, the second finger 6, the third finger 7, and the fourth finger 8 will be described. The configurations of the second finger 6, the third finger 7, and the fourth finger 8 have substantially the same configuration except for the link length and the like. Therefore, in the following, the configuration of the third finger 7 will be described as an example.

FIG. 17 is a perspective view of the third finger 7 of the robot hand 500. As is clear from the figure, the third finger is provided with a substantially L-shaped side support part 737 fixed to the palm portion 9.

As described above, since the support component 737 has an L-shape, a space for another mechanism including the first child 1 can be provided in the palm portion 9.

A servomotor 731 is arranged on the instep side of the support component 737. Further, from the upper end of the support component 737, the one link 711, the second link 712, and the third link 713 are connected via the second connecting shaft 741, the third connecting shaft 748, and the fourth connecting shaft 750, respectively. There is. The second connecting shaft 747 is provided with an absolute encoder 738 that detects the rotation angle thereof.

In the figure, the link that transmits the driving force from the servomotor 731 is protected by the first cover 781 that covers the palm portion 9 side and the second cover 780 that covers the instep portion side. ..

Next, the operation of the third finger 7 will be described with reference to FIG.

FIG. 18 is an explanatory diagram for explaining the operating principle of the third finger 7. As is clear from the figure, when the servomotor 731 is driven, the first spur gear 732, which is a small diameter spur gear attached to the output shaft thereof, rotates. Along with this rotation, the second spur gear 733, which is a large-diameter spur gear that meshes with the first spur gear 732, is driven to rotate.

When the second spur gear 733 rotates, the screw shaft 741 connected to the center of the second spur gear 733 and constituting the ball screw rotates. In response to this rotation, the substantially hishaku-shaped nut member 742 translates up and down.

As described above, according to the configuration in which the driving force is generated by using the ball screw, the gripping force at the time of gripping the object can be secured.

On the other hand, at the upper end of the support component 737, a V-shaped transmission link 745 whose center is rotatably supported by the fifth connecting shaft 746 is provided. The V-shaped transmission link 745 is rotatably connected to the nut member 742 at one end thereof via a seventh connecting shaft 744, and is connected to the base of the second link 712 at the other end.

In this state, when the nut member 742 is raised, the connecting end of the V-shaped transmission link 745 with the nut member 742 is pulled up. Further, the V-shaped transmission link 745 rotates around the fifth connecting shaft 746, and the opposite end, that is, the connecting end between the V-shaped transmission link 745 and the base of the second link 712 is pushed down. It will be. As a result, the first link 711 bends forward.

Further, as described above, since the second link 712 is rotatably supported by the third connecting shaft 748 with respect to the first link 711, the second connecting link is rooted by the V-shaped transmission link 745. When pushed down, the second link swings about the third connecting shaft 748.

At this time, since the support plate 735 that supports the lower end of the servomotor is rotatably connected to the lower end of the support component 737, it is configured to rotate by the reaction force received from the nut member 742.

That is, according to the above configuration, the first joint portion 721 and the second joint portion 722 can be interlocked and bent by using the driving force from one servomotor.

In the example of the figure, the second link 712 and the third link 713 are fixed. However, the present invention is not limited to such a configuration, and the third joint portion 713 may also be configured to be further interlocked.

(2. Modification example)
In the above-described embodiment, the robot hand 15 is configured from the palm portion 9 to the second finger 6 corresponding to the second finger (indicator) of the human hand and the third finger (middle finger) corresponding to the third finger (middle finger) of the human hand. It is assumed that the three fingers 7 and the fourth finger 8 corresponding to the fourth finger (medicine finger) of the human hand extend, but the present invention is not limited to such a configuration. Therefore, for example, a fifth finger corresponding to the little finger may be further provided, or more fingers may be provided. On the contrary, the number may be smaller, such as the third finger and the fourth child.

Further, the number of joints of each finger of the robot hand 15 is not limited to the above-described embodiment, and may be larger or smaller than the above-mentioned number of joints.

Although the embodiments of the present invention have been described above, the above embodiments are only a part of the application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiments. do not have. Further, the above embodiments can be appropriately combined as long as there is no contradiction.

The present invention can be used at least in an industry that manufactures robot hands, robots, and the like.

1 1st finger 6 2nd finger 7 3rd finger 8 4th finger 9 Palm part 500 Robot hand

Claims (17)

With the palm
The first finger extending from the side of the palm,
A hand mechanism including a tip finger extending from the tip of the palm portion.
The first finger is
A first link that is pivotally supported by the palm and swings around a first axis that is substantially parallel to the extension direction of the tip finger.
A hand mechanism comprising a second link that is pivotally supported by the first link and swings about a second axis that is slightly tilted from a direction perpendicular to the first axis. The hand mechanism according to claim 1, wherein the first axis is further arranged parallel to the palm portion. The hand mechanism according to claim 1 or 2, further comprising a third link that is pivotally supported by the second link and swings about a third axis perpendicular to the second axis. The hand mechanism according to claim 3, further comprising a fourth link that is pivotally supported by the third link and swings in conjunction with the third link. The hand mechanism according to claim 1, wherein the first finger is configured to face the tip surface of the bent tip finger by bending. The hand mechanism according to claim 1 to 5, wherein the first drive unit for driving the first link is supported by the palm portion. The hand mechanism according to claim 1 to 6, wherein the second drive unit for driving the second link is supported by the first link. The hand mechanism according to claim 4, wherein the third drive unit for driving the third link and the fourth link is supported by the second link. The hand mechanism according to claim 6, wherein the first drive unit is driven by using a ball screw. The hand mechanism according to claim 7, wherein the second drive unit is driven by using a ball screw. The hand mechanism according to claim 8, wherein the third drive unit is driven by using a ball screw. The hand mechanism according to claim 1, wherein each of the tip fingers has a four-node link structure that is interlockedly bent or extended by a tip finger drive unit arranged in the palm portion. The hand mechanism according to claim 12, wherein the tip finger drive unit is driven by using a ball screw. The hand mechanism according to claim 1, wherein the tip finger is three fingers including a second finger, a third finger, and a fourth finger. The rotation axis of the base portion of the third finger to the palm portion is sharp with the rotation axis of the base portion of the second finger to the palm portion and the rotation axis of the base portion of the fourth finger to the palm portion. The hand mechanism according to claim 14. A robot hand provided with the hand mechanism according to claims 1 to 15. A robot provided with the hand mechanism according to claims 1 to 15.

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