JP6948647B2 - A robot hand with a finger drive mechanism and a finger having the drive mechanism. - Google Patents

Description

The present invention relates to a finger drive mechanism of a robot hand capable of allowing a finger having a plurality of nodes to move according to an object, and a robot hand including a finger having the drive mechanism.

A robot hand that functions by operating articulated fingers having a plurality of nodes is equipped with the same number of actuators as the number of joints as a drive source to realize complicated movements. However, it is difficult to reduce the size by mounting a plurality of actuators, and the drive control becomes complicated in order to optimally operate each joint according to an object to be gripped or the like.

For this reason, even in a robot hand having articulated fingers, a drive mechanism that mounts one actuator as a drive source and realizes an operation such as gripping suitable for an object is disclosed in, for example, Patent Document 1. There is. In the drive mechanism described in Patent Document 1, by constructing two quadrupedal link mechanisms with six links including the proximal phalanx, the middle phalanx, and the distal phalanx of the finger, one actuator can be used to connect the proximal interphalangeal joint. A configuration is adopted in which the proximal, middle and distal phalanx can be rotationally driven around the three joints, the interphalangeal joint and the distal interphalangeal joint. With this configuration, it is possible to operate and grip the proximal phalanx, the middle phalanx, and the terminal phalanx according to the shape of the object while realizing miniaturization.

JP-A-2002-103269

However, the finger drive mechanism of the robot hand as described in Patent Document 1 adopts a configuration in which the proximal phalanx, middle phalanx and end phalanx of the finger are driven by two four-node link mechanisms consisting of six links. Therefore, each of its proximal phalanx, middle phalanx, and terminal phalanx cannot move relatively freely according to the shape of the object. For this reason, with this robot hand, it is necessary to perform work such as gripping within a range in which movement is restricted, and there is a problem that the work cannot be performed with a suitable movement suitable for the object.

Therefore, according to the present invention, the finger of the robot hand realizes the optimum movement with respect to the object while reducing the size by realizing the movement suitable for the shape of the work object of the proximal phalanx, the middle phalanx and the end phalanx of the finger with one actuator. It is intended to provide a drive mechanism for.

One aspect of the invention of the finger drive mechanism of the robot hand that solves the above problems has a proximal phalanx on the main body side of the robot hand, a distal phalanx on the fingertip side, and an intermediate phalanx between the proximal phalanx and the distal phalanx. An intermediate phalanx joint, which is a driving mechanism for the fingers of a robot hand that functions by transmitting the driving force of one actuator, and connects the proximal phalanx to the main body of the robot hand so as to be relatively rotatable. The proximal phalanx and the distal phalanx are provided with a proximal phalanx joint that rotatably connects the proximal phalanx and the intermediate phalanx, and a distal phalanx joint that rotatably connects the proximal phalanx and the distal phalanx. A drive link rotatably connected to the intermediate phalanx joint at one end and rotated by the actuator, and a proximal intermediate link rotatably connected to the proximal phalanx joint at one end. A base-side relay link whose both ends are rotatably connected to a first connecting shaft arranged on the other end side of the drive link and a second connecting shaft arranged on the other end side of the base-side intermediate link. The proximal phalanx link mechanism composed of the above, the intermediate phalanx, the distal phalanx, the distal intermediate link rotatably connected to the proximal phalanx joint at one end, and the distal intermediate. It is composed of a third connecting shaft arranged on the other end side of the link and a terminal relay link rotatably connected to both ends of the fourth connecting shaft arranged on the other end side of the end node. It is provided with a distal phalanx link mechanism and a posture holding means for holding a predetermined relative posture of the proximal phalanx, the intermediate phalanx and the distal phalanx when no load is applied to the proximal phalanx, the intermediate phalanx and the distal phalanx. However, the base-side intermediate link and the terminal-side intermediate link have one end side while maintaining a relative positional relationship by fixing the distance between the second connecting shaft and the third connecting shaft. It is rotatably supported by the common proximal interphalangeal joint, and the distal phalanx is different from the distal interphalangeal joint, the fourth connecting axis, and the fingertip at a position separated from the intermediate phalanx. It is placed at a location and the relative positional relationship is fixed.

One aspect of the invention of the robot hand that solves the above-mentioned problems is a robot hand having at least two or more sets of the fingers provided with the above-mentioned drive mechanism, and the driving force of the actuator is transmitted to the drive link for each finger. It is equipped with a transmission mechanism that allows it to function.

As described above, according to one aspect of the present invention, the proximal phalanx link mechanism composed of the proximal phalanx, the driving link, the proximal intermediate link and the proximal relay link, and the proximal phalanx, the distal segment, the distal intermediate link and the distal link. It is equipped with a terminal four-node link mechanism composed of side relay links, and the proximal intermediate link and the terminal intermediate link are rotatably supported with one end side in common while maintaining the relative positional relationship. The drive link is rotated by transmitting the driving force of one actuator while the relative positional relationship of the fingertip with respect to the fingertip is fixed in a predetermined manner.

This configuration allows the base, middle and end nodes to function as separate links between the base intermediate link and the other end of the end intermediate link, allowing the proximal, middle and end nodes to rotate in sequence without restriction. You can follow the object up to your fingertips.

Therefore, the movement of the proximal phalanx, the middle phalanx, and the end phalanx according to the shape of the object can be realized by one actuator, and the finger drive mechanism of the robot hand that realizes the optimum movement with respect to the object while being miniaturized. Can be provided.

FIG. 1 is a diagram showing a robot hand equipped with a finger drive mechanism according to an embodiment of the present invention, and is a perspective view showing the appearance thereof. FIG. 2 is a perspective view from the fingertip side showing the drive mechanism. FIG. 3 is a perspective view from the fingertip showing the drive mechanism. FIG. 4 is a link configuration diagram for modeling and explaining a link element in the drive mechanism. FIG. 5 is a perspective view showing the components of the proximal phalanx. FIG. 6 is a perspective view showing the components of the middle section. FIG. 7 is a perspective view showing the components of the last section. FIG. 8 is a perspective view showing the components of the drive link. FIG. 9 is a perspective view showing the components of the base relay link. FIG. 10 is a perspective view showing the components of the base side intermediate link and the end side intermediate link. FIG. 11 is a perspective view showing the components of the end relay link. FIG. 12 is a perspective view showing a component of a drive link different from that of FIG. FIG. 13 is a side view showing the posture of the finger during standby for driving. FIG. 14 is a side view showing a posture during driving of the finger. FIG. 15 is a side view showing the posture when the finger is stopped. FIG. 16 is a side view showing a posture during driving when gripping a thin object. FIG. 17 is a side view showing a posture during driving following FIG. FIG. 18 is a side view showing the posture of the object in the gripped state following FIG. FIG. 19 is a side view showing a posture of a thin object in a gripped state. FIG. 20 is a side view showing a posture during driving when gripping a thick object. FIG. 21 is a side view showing the posture of the object in the gripped state following FIG. FIG. 22 is a side view showing a posture of a thick object in a gripped state. FIG. 23 is a perspective view showing a posture when the finger is stopped. FIG. 24 is a side view illustrating the avoidance of damage caused by the external environment of the finger. FIG. 25 is a perspective view showing components of a proximal phalanx different from those in FIG. 5, which describes another aspect of the angle detecting means. FIG. 26 is a perspective view showing a component of a middle section different from that of FIG. 6, which describes another aspect of the angle detecting means. FIG. 27 is a perspective view showing components of a base intermediate link and a terminal intermediate link different from those in FIG. 10, illustrating another aspect of the angle detecting means. FIG. 28 is an enlarged plan view of a main part configuration for explaining another aspect of the posture holding means.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 to 24 are views showing a robot hand equipped with a finger drive mechanism according to an embodiment of the present invention.

In FIGS. 1 to 3, the robot hand 100 is a robot (not shown) via the wrist 109 so as to drive three fingers 101 (101A, 101B, 101C) to perform work such as grasping a work target. It is attached to the main body side. The robot hand 100 is mounted on, for example, a humanoid robot, an arm-type robot, or the like, and cooperates with other robots to realize various smooth operations.

In the robot hand 100, fingers 101 are arranged at three positions in the palm surface 106 of the palm (robot hand main body) 105 attached to the wrist 109 to grip the work target, and one end side of the palm surface 106. Fingers 101A and 101C are arranged on both end sides of 106a, and fingers 101B are arranged at the center of opposite end sides 106b. The fingers 101A to 101C grip the work object by relatively rotating in the direction in which the proximal phalanx 111, the middle phalanx 121, and the terminal phalanx 131 approach each other between the end sides 106a and 106b of the palm surface 106. It is laid out so that it can be done.

The finger 101 is rotatably connected and supported by the intermediate interphalangeal joint 112 in which one end side of the proximal phalanx 111 is arranged on the palm surface 106 side (either the same surface, the medial side, or the lateral side) of the palm 105. The other end side of the proximal phalanx 111 and one end side of the middle phalanx 121 are connected and supported by the proximal interphalangeal joint 122 so as to be relatively rotatable, and the other end side of the middle phalanx 121 and one end side of the terminal phalanx 131 are connected and supported. It is connected and supported to the distal interphalangeal joint 132 so as to be relatively rotatable, and the other end side of the distal interphalangeal joint 131 functions as a fingertip 139 described later.

The finger 101 includes a proximal phalanx link mechanism 103 that includes the proximal phalanx 111 as a link, and a distal phalanx link mechanism 104 that includes the intermediate phalanx 121 and the distal phalanx 131 as links (see FIG. 4). By transmitting the driving force of one actuator 110, it is constructed so as to function by relatively rotating each of its base section 111, middle section 121, and end section 131.

As will be described later, the base four-node link mechanism 103 and the terminal four-node link mechanism 104 are arranged so that the four links form a trapezoid that approximates a triangle, and the individual links rotate relative to each other. It is freely connected.

In the proximal phalanx link mechanism 103, the proximal phalanx relay link 113 is arranged on the opposite side to the proximal phalanx 111, and the proximal phalanx 111 and the finger base (palm surface 106) side of the proximal phalanx relay link 113 are connected by the drive link 114. At the same time, the fingertip 139 side is connected by the base side intermediate link 115. The proximal phalanx 111 is rotatably connected to the end of the drive link 114 by the interphalangeal joint 112, and the fingertip 139 side is rotated by the end of the proximal interphalangeal link 115 and the proximal interphalangeal joint 122. It is freely connected. The fingertip side of the base side relay link 113 is rotatably connected to the end of the drive link 114 by the first connecting shaft 116, and the fingertip 139 side is rotatably connected to the end of the base side intermediate link 115 by the second connecting shaft 117. Is connected to.

In the terminal four-node link mechanism 104, the terminal relay link 123 is arranged on the opposite side to the intermediate section 121, and the fingertip side of the middle section 121 and the terminal relay link 123 is connected by the terminal intermediate link 125. , The fingertip 139 side is connected by the terminal node 131. In the intermediate phalanx 121, the fingertip side is rotatably connected to the end of the distal interphalangeal link 125 by the proximal interphalangeal joint 122, and the fingertip 139 side is rotated by the end of the distal interphalangeal joint 131 and the distal interphalangeal joint 132. It is freely connected. The fingertip side of the end relay link 123 is rotatably connected to the end of the end intermediate link 125 by the third connecting shaft 126, and the fingertip 139 side is rotatably connected to the end of the end node 131 by the fourth connecting shaft 127. It is connected.

The proximal interphalangeal link 115 and the distal interphalangeal link 125 share a proximal interphalangeal joint 122 located at one apex of the intermediate link plate 120 (see FIG. 10), which is formed in a substantially triangular plate shape. The ends of the proximal phalanx 111 and the middle phalanx 121 are rotatably connected by utilizing the second connecting shaft 117 and the third connecting shaft located at the other two tops in the triangle of the intermediate link plate 120. It is constructed so as to function by rotatably connecting the ends of the base relay link 113 and the end relay link 123 to the 126. That is, the intermediate link plate 120 fixes the relative positional relationship between the proximal interphalangeal joint 122 and the second and third connecting shafts 117 and 126, and the proximal interphalangeal link 115 and the intermediate link 115 between them. While maintaining the relative posture of the distal intermediate link 125, the proximal interphalangeal joint 122 is rotatably maintained in a connected state. Therefore, the intermediate link plate 120 includes a link that rotates about the proximal interphalangeal joint 122 while maintaining the relative positional relationship between the second and third connecting shafts 117 and 126. Therefore, the base side relay link 113, the base side intermediate link 115, the end side intermediate link 125, and the end side relay link 123, which are rotatably connected to the second and third connecting shafts 117 and 126, are interlocked with each other. Communicate the movement to.

The distal phalanx 131 rotatably connects the intermediate phalanx 121 and the fingertip 139 side of the distal relay link 123 while maintaining the distance between the distal interphalangeal joints 132 on both ends and the fourth connecting shaft 127. The fingertip 139, which is shaped to be separated from the distal interphalangeal joint 132 in the extension direction of the intermediate phalanx 121, can be rotated relative to the fourth connecting shaft 127 while maintaining the relative positional relationship. It is designed to function as a fingertip. That is, the distal interphalangeal joint 132, the fourth connecting shaft 127, and the fingertip 139 are rotatably constructed while the relative positional relationships are fixed.

Then, as shown in FIG. 4 as a model diagram of the link constituting the drive mechanism of the finger 101, in the proximal phalanx link mechanism 103, the proximal phalanx 111 and the proximal relay link which are a part of the length of the finger 101 The 113 is formed to have the same length, and the proximal intermediate link 115 is formed to be less than half and about 1/3 shorter than the drive link 114 having a thickness near the middle interphalangeal joint 112 of the finger 101. There is. Similarly, in the distal phalanx link mechanism 104, the intermediate phalanx 121 and the distal relay link 123, which are part of the length of the finger 101, are formed to have the same length, and the proximal interphalangeal interphalangeal of the finger 101 is formed. The distal interphalangeal 131 is formed in a short length of about 1/3, which is less than half of the distal intermediate link 125 having a thickness near the joint 122.

Therefore, when the finger 101 is extended as much as possible, in the base-side four-joint link mechanism 103, the base-side relay link 113 and the base-side intermediate link 115 are in a posture in which they are continuous as linearly as possible. A second connecting shaft 117 that rotatably connects the base relay link 113 and the base intermediate link 115 is a line segment between the proximal interphalangeal joints 122 on both ends thereof and the first connecting shaft 116. By approaching L1 (the first virtual link 119 described later) on the outside, it is manufactured so as to form a shape substantially similar to a triangle as a whole. In the terminal four-node link mechanism 104, the terminal relay link 123 and the terminal 131 are in a posture in which they are continuous as linearly as possible, and the terminal relay link 123 and the terminal 131 are rotatably connected to each other. The four connecting shafts 127 are generally approximated by approaching the line segment L2 (second virtual link 129 described later) between the third connecting shaft 126 on both ends thereof and the distal interphalangeal joint 132 on the outside. It is made to form a shape that resembles a triangle.

With this configuration, in the proximal phalanx link mechanism 103, when a load that restricts movement is not applied to the proximal phalanx 111 or the like, the connection posture (link) is integrally with the drive link 114 rotated by the actuator 110. It is possible to rotate around the interphalangeal joint 112 while maintaining the shape). The proximal interphalangeal joint 112 with respect to the proximal interphalangeal joint 112, for example, when a limiting load is applied to stop the movement of the proximal phalanx 111, such as when the proximal phalanx 111 hits a work object. The proximal interphalangeal joint 122 (the distal interphalangeal link 125) allows the proximal interphalangeal link 113 to move to the fingertip 139 side in conjunction with the drive link 114 that rotates about. Rotate around. In this base-side four-joint link mechanism 103, since the base-side intermediate link 115 is formed to be less than half the length of the drive link 114, the end-side intermediate link 125 on the fingertip 139 side of the base-side relay link 113 is greatly rotated. The range of rotation at the proximal interphalangeal joint 122 can be increased. In the present embodiment, the base-side intermediate link 115 is made to have a size less than half that of the drive link 114, but it can be sufficiently functioned by making the drive link 114> the size of the base-side intermediate link 115. Needless to say, you can do it.

At this time, in the distal interphalangeal link mechanism 104, as in the case of the proximal interphalangeal link mechanism 103, when a load that restricts movement is not applied to the intermediate phalanx 121 or the like, the proximal interphalangeal joint 122 is used. It can rotate around the proximal interphalangeal joint 122 while maintaining the relative connection posture (link shape) with the distal intermediate link 125 integrated with the proximal interphalangeal link 115 that rotates about the center. The distal interphalangeal joint of the distal interphalangeal joint 104 refers to the proximal interphalangeal joint with respect to the intermediate phalanx 121 that stops when a limiting load is applied to stop the movement, for example, when the intermediate phalanx 121 hits a work object. The distal phalanx 131 rotates about the distal interphalangeal joint 132 so that the distal relay link 123 moves toward the fingertip 139 in conjunction with the distal intermediate link 125 that rotates about 122. Even in this terminal four-node link mechanism 104, since the terminal 131 is formed to be less than half the length of the terminal intermediate link 125, the terminal 131 on the fingertip 139 side of the terminal relay link 123 can be greatly rotated. The range of rotation at the distal interphalangeal joint 132 can be increased. In the present embodiment, the terminal node 131 is made to have a size less than half that of the terminal intermediate link 125, but it can be sufficiently functioned by making the terminal intermediate link 125> the dimension of the terminal node 131. Needless to say.

Then, the distal phalanx 131 can abut against the work target by rotating the fingertip 139, which has a fixed relative positional relationship (posture) around the distal interphalangeal joint 132, and the proximal phalanx 111 and the middle phalanx 131. The work object can be gripped together with the knot 121.

Specifically, as shown in FIG. 5, the proximal phalanx 111 is configured such that shaft holes 111a and 111b are formed on both ends of a pair of phalanx plates 111P connected and fixed by an intermediate frame 111F, respectively. .. As shown in FIG. 6, the middle section 121 is configured such that the support shafts 121S1 and 121S2 are fixed to both ends of a pair of middle section plates 121P connected and fixed by the intermediate frame 121F so as to function as shafts, respectively. There is. As shown in FIG. 7, the end node 131 has a shaft hole 131a formed on one end side of a pair of end node plates 131P connected and fixed by the fingertip frame 131F, and one end side is connected and fixed to the fingertip frame 131F. A shaft hole 131b is formed on the other end side of the support plate 131S.

Further, as shown in FIG. 8, the drive link 114 is configured by forming shaft holes 114a and 114b on both ends of the drive link plate 114P, respectively. As shown in FIG. 9, the base-side relay link 113 is configured by forming shaft holes 113a and 113b on both ends of a pair of base-side relay link plates 113P connected and fixed by an intermediate frame 113F, respectively. As shown in FIG. 10, the base side intermediate link 115 and the end side intermediate link 125 are configured by forming shaft holes 120a, 120b, and 120c at the tops of the triangles of the above-mentioned intermediate link plate 120, respectively. .. As shown in FIG. 11, the terminal relay link 123 is configured such that shaft holes 123a and 123b are formed on both ends of a pair of terminal relay link plates 123P connected and fixed by an intermediate frame 123F, respectively.

Specifically, one end side of the pair of proximal phalanx plates 111P is rotatably supported by inserting a connecting shaft 114S, which will be described later, into the shaft hole 111a. As a result, one end side of the proximal phalanx 111 is relatively rotatably connected by the middle hand interphalangeal joint 112 (shaft hole 111a and connecting shaft 114S).

Further, one end side of the pair of drive link plates 114P is fixed by inserting a connecting shaft 114S, which will be described later, into the shaft hole 114a. As a result, one end side of the drive link 114 is connected so as to rotate integrally by the middle hand interphalangeal joint 112 (shaft hole 114a and connecting shaft 114S).

One end side of the pair of intermediate phalanx plates 121P is formed at a narrow separation distance so as to be located between the other ends of the phalanx plate 111P, and the support shaft 121S1 is fixed between them. Both ends of 121S1 project from the outer surface on one end side. The other end side of the pair of proximal phalanx plates 111P is rotatably supported by fitting both ends of the support shaft 121S1 of the intermediate phalanx plate 121P into the shaft hole 111b. Similar to the proximal phalanx plate 111P, the one end side top of the intermediate link plate 120 is rotatably supported by inserting the support shaft 121S1 of the intermediate phalanx plate 121P into the shaft hole 120a. As a result, the other end side of the proximal phalanx 111, one end side of the middle phalanx 121, and one end side of the proximal interphalangeal link 115 and the distal interphalangeal link 125 are connected to the proximal interphalangeal joints 122 (shaft holes 111b, 120a and It is connected so as to be relatively rotatable by the support shaft 121S1).

Further, the other end side of the pair of middle node plates 121P is formed at a distance equivalent to that of the proximal phalanx plate 111P so that one end side of the terminal node plate 131P is located between them, and the support shaft 121S2 is fixed between them. There is. One end side of the pair of end node plates 131P is rotatably supported by inserting the support shaft 121S2 of the middle node plate 121P into the shaft hole 131a. As a result, the other end side of the intermediate phalanx 121 and the one end side of the end node 131 are relatively rotatably connected by the distal interphalangeal joint 132 (shaft hole 131a and support shaft 121S2).

The shaft holes 113a and 113b on both ends of the base relay link plate 113P and the shaft holes 114b and 120b on the other end of the drive link plate 114P and the base side top of the intermediate link plate 120 are the first connecting shafts 116 and 120b. The connecting shafts 116S and 117S of the two connecting shafts 117 are inserted and connected so as to be relatively rotatable. As a result, both ends of the base relay link 113, the other end of the drive link 114, and the other end of the base intermediate link 115 are connected to the first connecting shaft 116 and the second connecting shaft 117 (shaft holes 113a, 113b and). It is connected so as to be relatively rotatable by the connecting shafts 116S and 117S).

The shaft holes 123a and 123b on both ends of the terminal relay link plate 123P and the shaft holes 131b of the terminal top of the intermediate link plate 120 and the support plate 131S are the connecting shafts of the third connecting shaft 126 and the fourth connecting shaft 127. 126S and 127S are inserted and connected so as to be relatively rotatable. As a result, both ends of the end relay link 123, the other end of the end intermediate link 125, and the other end of the end node 131 are connected to the third connecting shaft 126 and the fourth connecting shaft 127 (shaft holes 123a, 123b and connecting). The shafts 126S and 127S) are connected so as to be relatively rotatable.

By the way, the fingertip frame 131F between the pair of end node plates 131P is formed in a tapered shape that gradually becomes thinner as the distance from one end side toward the other end side of the shaft hole 131a side increases, and functions suitably as a fingertip 139. It is made like this. The support plate 131S is screwed and fixed to one side of the fingertip frame 131F at one end side separated from the other end side where the shaft hole 131b is formed. As a result, the end node 131 is connected so as to be relatively rotatable around one or both of the shaft holes 131a and 131b on both end sides, and functions as one link of the end side four-node link mechanism 104.

The proximal interphalangeal joint 122 and the distal interphalangeal joint 132 have the proximal phalanx plate 111P and the intermediate phalanx plate 121P, and the intermediate phalanx plate 121P and the distal phalanx plate 131P, respectively, extending substantially linearly. So-called torsion springs (elastic members) 141 and 142, which apply elastic force so as to be in a posture, are installed so as to be located around the support shafts 121S1 and 121S2, respectively. The torsion springs 141 and 142 are stretched when, for example, the middle phalanx plate 121P with respect to the proximal phalanx plate 111P and the distal phalanx plate 131P with respect to the middle phalanx plate 121P rotate in a direction approaching each other from an unloaded state. It is installed so as to give an elastic force to urge the person to return to the posture.

Further, as shown in FIGS. 5 to 7, abutting surfaces 111t1, 121t1, 121t2, 131t2, which function as stoppers for limiting excessive rotation, are arranged around the torsion springs 141 and 142, respectively. .. As shown in FIG. 5, the abutting surface 111t1 is formed on one side of the longitudinal end surface separated from the shaft hole 111b of the base plate 111P in the reverse rotation direction, and one side in the rotation direction is formed in a circular shape to rotate. On the other hand, it is formed so as to allow the reverse rotation, but by being formed in a square shape on the side in the reverse rotation direction, it functions to abut on the opposite side and limit the reverse rotation. As shown in FIG. 6, the abutting surface 121t2 is formed on the facing surface facing the abutting surface 111t1 of the proximal phalanx plate 111P in the vicinity of the shaft hole 121a of the intermediate phalanx plate 121P, and abuts on the abutting surface 111t1. Functions to limit its reverse rotation. Similarly, as shown in FIG. 6, the abutting surface 121t1 is formed on one side of the longitudinal end surface separated from the shaft hole 121b of the middle node plate 121P in the reverse rotation direction, and one side in the rotation direction is circular. While it is formed to allow rotation, it is located on the reverse rotation direction side and is formed in a square shape so as to abut against the opposite side and function to limit reverse rotation. As shown in FIG. 7, the abutting surface 131t2 is formed on the facing surface facing the abutting surface 121t1 of the middle node plate 121P in the vicinity of the shaft hole 131a of the end node plate 131P, and abuts against the abutting surface 121t1. It works to limit its reverse rotation.

The abutting surfaces 111t1, 121t2 and the abutting surfaces 121t1, 131t2 are located between the proximal interphalangeal joint 122 and the distal interphalangeal joint from the state where the proximal phalanx plate 111P, the intermediate phalanx plate 121P and the intermediate phalanx plate 131P are close to each other. The torsion springs 141 and 142 rotate around the joint 132 in the direction of returning to the stretched posture, and are formed so as to abut each other when attempting to rotate further from the stretched posture. As a result, the proximal phalanx plate 111P, the intermediate phalanx plate 121P, and the intermediate phalanx plate 131P can be maintained in a state of returning to the extended posture by being restricted from rotating too much from the extended posture, and the finger 101 can be maintained. Warping can be reliably prevented. That is, the torsion springs 141 and 142 and the abutting surfaces 111t1, 121t1, 121t2 and 131t2 form the posture holding means.

The shapes of the abutting surfaces 111t1, 121t1, 121t2, and 131t2 are not limited to the shapes shown in FIGS. 5 to 7 adopted in the present embodiment. In the embodiment of the present invention, as shown in detail, the abutting surface 111t1 is provided in the vicinity of the proximal interphalangeal joint 122 of the proximal phalanx 111 in a planar shape, and the proximal interphalangeal joint 122 of the intermediate phalanx 121 is provided. The abutting surface 121t2 is provided in the vicinity in a planar shape. When the proximal phalanx 111 and the middle phalanx 121 try to rotate further from the extended posture, the planar abutting surface 111t1 and the planar abutting surface 121t2 are formed so as to abut against each other. It is configured and installed as a stopper having enough strength to receive a large force by forming a planar shape that abuts against each other. Similarly, in the embodiment of the present invention, as shown in the figure, the abutting surface 121t1 is provided in the vicinity of the distal interphalangeal joint 132 of the intermediate phalanx 121 in a planar manner, and is provided in the vicinity of the distal interphalangeal joint 132 of the distal phalanx 131. The abutting surface 131t2 is provided in a planar shape. When the middle node 121 and the terminal node 131 try to rotate further from the stretched posture, the planar abutting surface 121t1 and the planar abutting surface 131t2 are formed so as to abut against each other. It is configured and installed as a stopper having enough strength to receive a large force by forming a planar shape that abuts against each other.

As a result, the finger 101 can stand by, for example, in a posture in which the proximal phalanx plate 111P, the intermediate phalanx plate 121P, and the distal phalanx plate 131P extend substantially linearly when there is no load as shown in FIGS. 13 to 15.

Further, returning to FIGS. 1 to 3, the pair of proximal phalanx plates 111P in the middle hand interphalangeal joint 112 for each finger 101A to 101C arranged in the palm surface 106 of the palm 105 are each shaft hole on one end side. The connecting shaft 114S is inserted into the 111a so as to be relatively rotatable and supported. On the other hand, the drive link plate 114P in the middle finger internodal joint 112 is rotatably supported by being located between the proximal phalanx plates 111P and the connecting shaft 114S being inserted into the shaft hole 114a on one end side. At the same time, each of them receives the driving force of the actuator 110 and is driven by being rotated in the forward and reverse directions around the connecting shaft 114S (shaft hole 114a).

As shown in FIGS. 1 to 3 and 8, the drive link plate 114P of the finger 101A has a worm wheel 114W fixed on the outer peripheral side with the shaft hole 114a on one end side as the axis, and the shaft hole 114a thereof. The connecting shaft 114S1 is fixed so as not to rotate relative to each other.

On the other hand, the actuator 110 outputs a driving force by rotationally driving the transmission shaft 151 via a transmission device 110T having a built-in planetary gear and having a function such as deceleration. A cylindrical worm 151W that meshes with the worm wheel 114W of the drive link plate 114P of the finger 101A is fixed to the tip of the 151 so as to rotate coaxially.

As a result, in the middle finger internodal joint 112 of the finger 101A, the driving force of the actuator 110 is directly decelerated and transmitted via the cylindrical worm 151W and the worm wheel 114W, and the driving link plate 114P is rotated in the forward and reverse directions and driven thereof. The connecting shaft 114S1 inserted and fixed in the shaft hole 114a of the link plate 114P is integrally rotated.

As shown in FIGS. 1 to 3 and 12, the drive link plate 114P of the finger 101C has a connecting shaft 114S1 common to the finger 101A in the shaft hole 114a without the worm wheel 114W being fixed as in the finger 101A. It is plugged in and fixed so that it cannot rotate relative to each other.

As a result, in the middle finger internode joint 112 of the finger 101C, the driving force of the same actuator 110 is transmitted so as to rotate integrally via the connecting shaft 114S1 common to the finger 101A, and the driving link plate 114P becomes constant velocity. It is rotated forward and reverse.

As shown in FIGS. 1 to 3 and 8, the drive link plate 114P of the finger 101B has a worm wheel 114W fixed to the outer peripheral side with the shaft hole 114a on one end side as the axis, similarly to the finger 101A. The driving force of the actuator 110 is transmitted by a path different from that of the fingers 101A and 101C, and a connecting shaft 114S2 separate from the fingers 101A and 101C is inserted into the shaft hole 114a and fixed so as not to rotate relative to each other. In the present embodiment, it is fixed to detect the rotation angle as described later, but if it can rotate freely, it may be supported so that it can rotate relative to each other).

On the other hand, in the actuator 110, apart from the cylindrical worm 151W on the tip side of the transmission shaft 151, the drive pulley 151P is fixed between the cylindrical worm 151W and the transmission device 110T so that the transmission belt 153 cannot rotate relative to each other. It is wound together with the driven pulley 154P. The driven pulley 154P is arranged at a distance position on the lower side near the finger 101C from the drive pulley 151P in the lower part near the finger 101A, and is rotatably supported inside the palm 105 so as to be driven and rotated by the transmission belt 153. Further, the transmission gear 151G is fixed to the driven pulley 154P so as to rotate coaxially, and the relay gear 155 meshes with the transmission gear 151G to apply the driving force of the actuator 110 to the driving pulley 151P and the transmission belt 153. It is designed to be transmitted via. The relay gear 155 is fixed to the axis so that the transmission shaft 157 rotates coaxially, and the cylindrical worm 157W is fixed to the opposite end of the transmission shaft 157 so that the transmission shaft 157 rotates coaxially. ing. The worm wheel 114W of the drive link plate 114P in which the connecting shaft 114S2 is inserted into the shaft hole 114a on one end side meshes with the cylindrical worm 157W so that the cylindrical worm 157W is rotated in the forward and reverse directions.

As a result, in the middle finger internode joint 112 of the finger 101B, the driving force of the same actuator 110 is indirectly decelerated and transmitted from the drive pulley 151P and the transmission belt 153 via the cylindrical worm 157W and the worm wheel 114W, and the drive link plate. 114P is rotated forward and reverse. That is, the transmission shaft 151, 157, the cylindrical worm 151W, 157W, the worm wheel 114W, the drive pulley 151P, the driven pulley 154P, the transmission belt 153, the transmission gear 151G, and the relay gear 155 provide a transmission mechanism for transmitting the driving force of the actuator 110. It is configured.

Then, in the robot hand 100, the control unit 100C acquires the relative bending states of the proximal phalanx 111, the middle phalanx 121, and the terminal phalanx 131 of the fingers 101A to 101C, and realizes the driving according to the target and grips the robot hand 100. It is designed to work. In the present embodiment, a case where the control unit 100C is installed on the robot hand 100 to control the operation in an integrated manner will be described as an example, but the present invention is not limited to this, and for example, the robot main body in which the robot hand 100 is installed is described. Needless to say, it may be applied to a form in which the control is controlled by the side.

The control unit 100C of the robot hand 100 is composed of a so-called CPU (Central Processing Unit), which is a central processing unit that executes a control program stored in the memory 100M. The control unit 100C controls, for example, the forward / reverse drive of the actuator 110 based on various parameters preset in the memory 100M, various sensor information acquired by an angle sensor described later, and the like, for example. With the columnar work W1 as shown in FIG. 16 as the work target, the work of gripping or the like is executed under the optimum conditions.

The control unit 100C of the robot hand 100 directly detects and acquires the operating status of the middle interphalangeal joint 112 and the proximal interphalangeal joint 122 by a sensor element described later, and also acquires the operating status of the distal interphalangeal joint 132. Is calculated and acquired using the acquired sensor information and the dimensional information (geometric relationship) of each part stored in the memory 100M.

Specifically, the control unit 100C of the robot hand 100 is connected to the encoder 110E that detects the rotation angle of the drive output shaft (not shown) of the actuator 110. The control unit 100C directly detects and acquires the relative rotation angle 112α of the drive link plate 114P from the reference position B on the palm 105 side in the link model of the finger 101 shown in FIG. 4 based on the detection information of the encoder 110E. The relative rotation angle 112α of the drive link plate 114P may be detected in consideration of the reduction ratio by the transmission device 110T.

Further, as shown in FIG. 5, connecting shafts 114S1 and 114S2 that rotate integrally with the drive link plate 114P are inserted into one end side of the proximal phalanx plate 111P and are supported on one side outer surface of the shaft hole 111a that supports the base plate 111P so as to be relatively rotatable. A reading magnet 111 rm, which is one of the components of the rotation sensor element, is embedded and protrudes in a protruding shape. As shown in FIGS. 2 and 3, the reading head 111rh, which is the other component of the rotation sensor element, rotatably supports the connecting shafts 114S1 and 114S2 on the palm 105 side to function as the interphalangeal joint 112. It is installed on the member of the above, is located around the reading magnet 111 rm, and is connected to the control unit 100C. The control unit 100C directly detects the relative rotation angle 112β of the proximal phalanx plate 111P from the reference position B on the palm 105 side in the link model of the finger 101 shown in FIG. 4 from the relative rotation of the reading magnet 111rm detected by the reading head 111rh. get. In FIGS. 2 and 3, as the sensor line connected to the control unit 100C, only one system of the reading head 111rh is shown as a alternate long and short dash line, and the other systems are omitted.

Further, as shown in FIG. 6, one end of the support shaft 121S1 projects from the outer surface on one end side of the middle section plate 121P, and a reading magnet 121rm which is one component of the rotation sensor element is embedded. There is. As shown in FIGS. 2 and 3, the reading head 121rh, which is the other component of the rotation sensor element, has a shaft hole on the other end side of the phalanx plate 111P into which one end portion of the support shaft 121S1 is rotatably fitted. It is located around 111b and is connected to the control unit 100C. The control unit 100C directly acquires the relative rotation angle 122α of the intermediate phalanx plate 121P with respect to the proximal phalanx plate 111P from the relative rotation of the reading magnet 121rm detected by the reading head 121rh.

In this way, as shown in FIG. 4, the control unit 100C of the robot hand 100 has the intermediate interphalangeal joint from the reference position B on the finger 101 of the drive link plate 114P based on the sensor information of the encoder 110E of the actuator 110. The rotation angle 112α around 112 (shaft holes 111a, 114a) is directly acquired, and based on the rotation information of the reading magnet 111rm detected by the reading head 111rh, the base plate 111P from the reference position B on the finger 101 of the base plate 111P. The rotation angle 112β around the middle interphalangeal joint 112 is directly acquired, and further, the proximal interphalangeal distance of the proximal interphalangeal plate 121P with respect to the proximal phalanx plate 111P based on the rotation information of the reading magnet 121rm detected by the reading head 121rh. The rotation angle 122α around the joint 122 (shaft holes 111b, 121a) is directly acquired.

On the other hand, the control unit 100C calculates and acquires the rotation angle 132γ around the distal interphalangeal joints 132 (shaft holes 121b, 131a) of the distal phalanx plate 131P with respect to the intermediate phalanx plate 121P.

Specifically, first, the control unit 100C subtracts the rotation angle 112α from the reference position B of the drive link plate 114P from the rotation angle 112β from the reference position B of the proximal phalanx plate 111P around the middle hand interphalangeal joint 112. By doing so, the rotation angle 112γ between the proximal phalanx plate 111P and the drive link plate 114P is calculated and acquired.

Next, the control unit 100C has a calculated rotation angle 112γ between the proximal phalanx plate 111P and the drive link plate 114P (hereinafter, the word “plate” may be omitted) and the link length of the proximal phalanx 111 (default). The length of the first virtual link 119 (line segment L1 between the shaft holes 111b and 114b) from the distance between the shaft holes 111a and 111b of the proximal phalanx plate 111P, which is omitted because the same applies hereinafter) and the link length of the drive link 114. Is calculated and acquired.

Next, the control unit 100C uses the calculated length of the first virtual link 119, the link length of the base node 111, and the link length of the drive link 114 to bring the first virtual link 119 close to the base node 111. The rotation angle 122β around the interphalangeal joint 122 is calculated and acquired.

Next, similarly, the control unit 100C is based on the calculated length of the first virtual link 119, the link length of the base relay link 113, and the link length of the base intermediate link 115 on the intermediate link plate 120. The angle of rotation 122γ around the proximal interphalangeal joint 122 between the virtual link 119 and the basal intermediate link 115 is calculated and acquired.

Next, the control unit 100C has a calculated rotation angle 122β between the first virtual link 119 and the proximal phalanx 111, a calculated rotation angle 122γ between the first virtual link 119 and the proximal intermediate link 115, and an intermediate link. A fixed angle 122δ around the proximal interphalangeal joint 122 between the proximal interphalangeal link 115 and the distal interphalangeal link 125 of the plate 120, and the proximal interphalangeal joint 122 between the proximal phalanx plate 111P and the intermediate phalanx plate 121P. From the detected rotation angle 122α around, the rotation angle 122ε around the proximal interphalangeal joint 122 between the intermediate phalanx 121 and the distal interphalangeal link 125 is calculated and acquired.

Next, the control unit 100C determines from the calculated rotation angle 122ε between the middle section 121 and the terminal intermediate link 125, the link length of the middle section 121, and the link length of the terminal intermediate link 125 on the intermediate link plate 120. 2 Calculate and acquire the length of the virtual link 129 (line segment L2 between the shaft holes 120c and 121b).

Next, the control unit 100C determines the second virtual link 129 and the middle from the calculated length of the second virtual link 129, the link length of the middle section 121, and the link length of the terminal intermediate link 125 in the intermediate link plate 120. The angle of rotation 132α around the distal interphalangeal joint 132 (shaft holes 121b, 131a) between the node 121 is calculated and acquired.

Next, the control unit 100C similarly obtains the second virtual link 129 and the terminal node 131 from the calculated length of the second virtual link 129, the link length of the terminal relay link 123, and the link length of the terminal node 131. The angle of rotation 132β around the distal interphalangeal joint 132 between them is calculated and acquired.

Next, the control unit 100C has a calculated rotation angle 132α between the second virtual link 129 and the middle node 121, a calculated rotation angle 132β between the second virtual link 129 and the terminal node 131, and a shaft hole of the terminal node plate 131P. Between the end node 131 that functions as a link from 131a to the shaft hole 131b on the other end side of the support plate 131S and the fingertip link from the shaft hole 131a of the end node plate 131P to the tip 139a of the fingertip 139 on the other end side of the fingertip frame 131F. The rotation angle 132γ at the distal interphalangeal joint 132 between the fingertip link and the extension line 121E of the middle node 121 (middle node plate 121P) is calculated and acquired from the fixed angle 133α around the shaft hole 131a.

In this way, the control unit 100C of the robot hand 100 can rotate the rotation angle 112α of the drive link 114 and the base joints 111 and the middle joints 121 from the encoder 110E, the reading magnets 111rm and 121rm, and the reading heads 111rh and 121rh. In addition to directly detecting and acquiring the angles 112β and 122α (joint angles of the proximal interphalangeal joint 112 and the proximal interphalangeal joint 122), the base quadrupedal link mechanism 103 and Using geometric information such as the dimensions and angles of the components of the distal interphalangeal link mechanism 104, the rotation angle 132γ of the fingertip 139 integrated with the distal interphalangeal joint 132 is calculated and acquired as the joint angle of the distal interphalangeal joint 132. can do. That is, in the robot hand 100, the number of sensor elements installed can be reduced, the cost can be reduced, and the installation space can be reduced to reduce the size.

Then, the control unit 100C of the robot hand 100 executes a control program in the memory 100M to control the forward / reverse drive of the actuator 110 based on various setting parameters and various sensor information, thereby performing various operations under optimum conditions. Run.

By the way, in this robot hand 100, the fingertips 139 of each finger 101A to 101C are placed on a virtual vertical plane 106V near the center of the palm surface 106 without applying a load to any of the proximal phalanx 111, the middle phalanx 121 and the terminal phalanx 131. When approaching (see FIG. 19) and facing each other at alternating adjacent positions across the virtual vertical plane 106V, the finger pad 139s of the fingertip 139 is set to be in full contact with the virtual vertical plane 106V. ing.

As a result, in the robot hand 100, the actuator 110 is driven forward and reverse, and the drive link 114 is driven and rotated around the middle hand interphalangeal joint 112 according to the meshing position of the worm wheel 114W and the cylindrical worm 151W and 157W. Therefore, the fingers 101A to 101C function in synchronization with each other. The robot hand 100 starts from a posture in which the fingertips 139 of the fingers 101A to 101C are largely separated from each other, and the fingertips 139 are operated in the direction of approaching each other, so that the base joint 111, the middle joint 121, and the terminal joint 131 are in the middle. The work W of the work target can be grasped by appropriately bending the interphalangeal joint 112, the proximal interphalangeal joint 122, and the distal interphalangeal joint 132.

For example, the finger 101 operates as shown in FIGS. 13 to 15, for example, by taking the finger 101A as an example when there is no load in which the work W to be worked does not exist. First, in the finger 101A, when no load is applied, the middle phalanx 121 is urged against the proximal phalanx 111, and the terminal phalanx 131 (finger tip 139) is urged against the middle phalanx 121 by the elastic force of the torsion springs 141 and 142. .. Therefore, the proximal phalanx 111, the intermediate phalanx 121, and the distal phalanx 131 are in a posture of extending substantially linearly, and the shapes of the proximal phalanx link mechanism 103 and the distal phalanx link mechanism 104 are maintained.

As shown in FIG. 13, the finger 101A of the robot hand 100 is held in the standby position where the drive link 114 is in the standby position between the worm wheel 114W and the cylindrical worm 151W, and is in a standby position so as to be largely separated from the fingertips 139 of the other fingers 101B. It is held in the posture. When the finger 101A is started from the standby posture, the driving link 114 moves between the middle finger joints as the cylindrical worm 151W is rotated by the driving force of the actuator 110 and the meshing position with the worm wheel 114W fluctuates. It rotates around the joint 112. Then, as shown in FIG. 14, the finger 101A is rotated in a direction approaching the fingertip 139 of the finger 101B, and the proximal phalanx 111, the middle phalanx 121, and the terminal phalanx 131 are shown in FIG. As described above, it is stopped at a position facing the palm surface 106 in a parallel posture. By taking the state shown in FIG. 15, the robot hand 100 can be put into a stopped state in which the fingers 101A to 101C are accommodated, as shown in FIG. 23, which will be described later.

Further, for example, the finger 101 operates as shown in FIGS. 16 to 18 when gripping the thin columnar work W1 to be worked. The work W1 has a cylindrical shape, and the fingers 101A and 101C operate in the same manner at the same time to perform the gripping operation. The operation will be described with reference to the drawings illustrating the fingers 101A.

First, the finger 101A of the robot hand 100 has a drive link as the cylindrical worm 151W is rotated by the driving force of the actuator 110 from the no-load standby state shown in FIG. 13 and the meshing position with the worm wheel 114W fluctuates. As the 114 rotates about the interphalangeal joint 112, as shown in FIG. 16, the proximal phalanx 111 abuts on the work W1 and further rotation is restricted. As it is, the driving link 114 of the finger 101A is further rotated around the intermediate interphalangeal joint 112, so that the proximal interphalangeal link mechanism 103 is deformed, and as shown in FIG. 17, the proximal interphalangeal link 113 is slid toward the fingertip 139 side, and the intermediate link plate 120 (base side intermediate link 115 and end side intermediate link 125) and the intermediate phalanx 121 push the proximal interphalangeal joint 122 against the elastic force of the torsion spring 141. It is rotated around the center. Then, while maintaining the shape of the terminal four-node link mechanism 104, the finger 101A abuts the middle node 121 against the work W1 and further rotation is restricted. At this time, after the intermediate link plate 120 (base intermediate link 115 and distal intermediate link 125) and the intermediate phalanx 121 are rotated to the limit around the proximal interphalangeal joint 122, the intermediate phalanx 121 is the work W1. As will be described later, the relative rotation of the distal interphalanges 131 against the elastic force of the torsion spring 142 is started together with the slide of the distal relay link 123 even before the collision.

In this robot hand 100, even after the intermediate phalanx 121 hits the work W1, the drive link 114 and the intermediate link plate 120 rotate around the intermediate interphalangeal joint 112 and the proximal interphalangeal joint 122. As shown in FIG. 18, the end relay link 123 is slid toward the fingertip 139 side due to the rotation limitation of the middle section 121. After this, in the finger 101A, the distal segment 131 is rotated around the distal interphalangeal joint 132 against the elastic force of the torsional spring 142, and the distal quadrulateral link mechanism 104 is deformed while the fingertip 139 is moved. By rotating around the distal interphalangeal joint 132, the finger pad 139s of the fingertip 139 is transferred to the state of being abutted against the work W1, and further rotation is restricted to maintain the gripping state. NS.

Further, for example, as shown in FIG. 19, when the work W to be worked is in the shape of a sheet, the work is aligned with the virtual vertical plane 106V near the center between the end sides 106a and 106b of the palm surface 106. By holding W and driving the robot hand 100, the fingers 101A to 101C remain in the no-load state shown in FIG. It is rotated while maintaining the linear extension posture of the nodes 121 and the end nodes 131. Then, the fingers 101A to 101C are transferred to a state in which the finger pads 139s of the fingertip 139 are in full contact with the sheet-shaped work W located on the virtual vertical plane 106V, and further rotation is restricted to grip the fingers 101A to 101C. Is maintained. That is, the robot hand 100 can hold the sheet-shaped work W by sandwiching it between the fingertips 139 of the fingers 101.

Further, for example, the finger 101 operates as shown in FIGS. 20 and 21 when gripping the thick plate-shaped work W2 to be worked.

First, for example, as shown in FIG. 20, the work W2 to be worked is held so as to be located near the center between the end sides 106a and 106b of the palm surface 106, and the robot hand 100 is driven to drive the finger 101A. As described above, 101C is rotated in the direction in which the fingertips 139 approach each other in the no-load state shown in FIG. 13, while maintaining the linear extension postures of the proximal phalanx 111, the middle phalanx 121, and the terminal phalanx 131. .. Then, the fingers 101A to 101C abut the other end side of the intermediate phalanx 121 against the work W2 located near the center of the palm surface 106, and further rotation is restricted.

In the fingers 101A to 101C, even after the intermediate phalanx 121 hits the work W2, the drive link 114 is further rotated around the interphalangeal joint 112, so that the proximal interphalangeal link mechanism 103 is deformed. , The intermediate link plate 120 is rotated around the proximal interphalangeal joint 122, and the distal relay link 123 is slid toward the fingertip 139 side. Then, as shown in FIG. 21, the fingers 101A to 101C are rotated around the distal interphalangeal joint 132 against the elastic force of the torsional spring 142, and the distal quadruple link mechanism 104 is moved. While being deformed, the fingertip 139 is rotated around its distal interphalangeal joint 132. As a result, the fingers 101A to 101C are transferred to a state in which the finger pads 139s of the fingertips 139 of the terminal node 131 face the work W2 and are abutted against each other, and further rotation is restricted to maintain the gripping state. At this time, the finger 101 of the robot hand 100 can be regarded as a node in which the abutting surfaces 111t1 and 121t2 of the proximal phalanx plate 111P and the intermediate phalanx plate 121P abut against each other and the proximal phalanx 111 and the intermediate phalanx 121 are integrated. The driving force of the actuator 110 is not wasted on the rotation of the middle section 121, and the work W2 can be efficiently gripped.

Further, for example, in the case of the robot hand 100, when the work W3 to be worked on is a cylinder having a diameter larger than the length of the intermediate phalanx 121 and cannot be grasped by one finger 101, as shown in FIG. Operate.

First, in the case of the work W1 described with reference to FIGS. 16 to 18, the work W3 to be worked is held so as to be located near the center between the end sides 106a and 106b of the palm surface 106 and the robot hand 100 is driven. It operates in the same manner as the above, and is gripped by the entire fingers 101A to 101C. In this case, the fingers 101A to 101C remain in the no-load state shown in FIG. The rotation is started as it is. Then, the fingers 101A to 101C are restricted from further rotation by sequentially abutting the proximal phalanx 111, the middle phalanx 121, and the fingertip 139 of the terminal phalanx 131 on the work W3 located near the center of the palm surface 106. As a result, it will be gripped.

Specifically, first, the fingers 101A to 101C of the robot hand 100 are rotated with the base nodes 111, middle nodes 121, and end nodes 131 in the no-load state shown in FIG. 13 in a linear extension posture, and the base nodes 111 work. When it hits W3 and further rotation is restricted, the intermediate phalanx 121 is rotated around the proximal interphalangeal joint 122 against the elastic force of the torsional spring 141. After this, when the intermediate phalanx 121 of the fingers 101A to 101C abuts on the work W3 and further rotation is restricted, the distal phalanx 131 further resists the elastic force of the torsion spring 142 and the distal interphalangeal joint 132. Is rotated around. Then, the terminal segment 131 (fingertip 139) of the fingers 101A to 101C is rotated around the distal interphalangeal joint 132, and the finger pad 139s of the fingertip 139 is transferred to the state where the finger pad 139s is abutted against the work W3. Further rotation is restricted and the gripping state is maintained.

As a result, the robot hand 100 drives the proximal phalanx link mechanism 103 and the distal phalanx link mechanism 104 so as to be separately deformed by the driving force of one actuator 110, thereby causing the work W to be worked. The proximal phalanx 111, the middle phalanx 121, and the terminal phalanx 131 can be sequentially rotated according to the shape of the phalanx, and the work W can be gripped with the fingertip 139 of the terminal phalanx 131 along.

By the way, for example, when a stop command is given, the control unit 100C of the robot hand 100 drives the actuator 110 in a no-load state as shown in FIG. While maintaining the linear extension posture of 131, the robot is rotated to a home state facing the palm surface 106 in a parallel posture to stop the robot. As a result, it is possible to minimize damage to the fingers 101A to 101C due to interference with the external environment.

When the fingers 101A to 101C are brought into the home state at the four corners of the palm surface 106 of the palm 105, the robot hand 100 has an installation surface that is larger than the most protruding parts of the base side relay link 113 and the end side relay link 123. A rib (protruding member) 191 having a size (height) separated from the palm surface 106 of the robot is arranged.

As a result, when the robot hand 100 accommodates the fingers 101A to 101C in the home state and stops the robot hand 100, as shown in FIG. 24, the base side relay link 113 and the end side relay link 123 of the fingers 101A to 101C, etc. It is possible to prevent the member EX or the like outside the device from colliding with the device and damaging it.

As described above, in the robot hand 100 equipped with the fingers 101A to 101C of the present embodiment, the base section 111, the middle section 121, and the end section 131 are formed into the shape of the work W to be worked by the driving force of one actuator 110. The work W can be sequentially rotated accordingly, and the work W can be gripped in an optimum state by aligning the fingertips 139 of the end node 131 with the outer surface of the work W.

Therefore, the proximal phalanx 111, the middle phalanx 121, and the terminal phalanx 131 of the finger 101 can be optimally driven by one actuator 110 according to the shape of the work W to be worked on, and the optimum movement with respect to the work W can be realized while reducing the size. be able to.

In the present embodiment, the reading magnets 111 rm and 121 rm and the reading heads 111 rh and 121 rh are installed on the intermediate interphalangeal joints 112 and the proximal interphalangeal joints 122, and the relative rotation angles of the proximal phalanx 111 and the intermediate phalanx 121 ( The joint angle) is directly detected and acquired by the control unit 100C as sensor information, and the relative rotation angle (joint angle) of the distal interphalangeal 131 is calculated and acquired using the dimensions and shapes of the proximal phalanx link mechanism 103 and the distal interphalangeal link mechanism 104. The case of doing so will be described as an example, but the present invention is not limited to this. For example, a sensor may be installed at the distal interphalangeal joint 132 to directly detect and acquire the sensor, but the present embodiment is more preferable in consideration of the sensor installation limitation, the component cost, and the like.

Further, in the present embodiment, an example in which the reading head 121rh and the reading magnet 121rm are installed on the proximal phalanx plate 111P side of the proximal phalanx 111 will be described, but the present invention is not limited to this. In another embodiment, for example, as shown in FIGS. 25 to 27, a sensor plate 121P2 is added to the outside of the middle section plate 121P of the middle section 121, and one of the rotation sensor elements is provided. The reading head 121rh, which is a component, is installed, and the reading magnet 121rm, which is the other component of the rotation sensor element, extends the support shaft 121S1 to be inserted into the shaft hole 120a of the intermediate link plate 120 to the sensor plate 121P2. It may be embedded so that it can be detected. Also in this case, the same effect as that of the above-described embodiment can be obtained.

Further, in the present embodiment, an example will be described in which the torsion springs 141 and 142 and the abutting surfaces 111t1, 121t1, 121t2 and 131t2 are installed as the posture holding means for holding the proximal phalanx 111, the middle phalanx 121 and the terminal phalanx 131 in the extended posture. However, it is not limited to this. As another embodiment, instead of this, for example, as a means (stopper) for limiting each of the proximal phalanx 111, the intermediate phalanx 121, and the terminal phalanx 131 from rotating too much from the stretched posture, FIG. 28 is shown. As described above, protrusions 111u1 and 121u1 are formed on the outer peripheral surfaces of the longitudinal end portions of the proximal phalanx plate 111P and the intermediate phalanx plate 121P, and the protrusions 121u2 and 131u2 abut against the protrusions 111u1 and 121u1 to limit excessive rotation. May be formed on the side surface of the middle phalanx plate 121P or the terminal phalanx plate 131P. In this case, the same effect can be obtained.

Although embodiments of the present invention have been disclosed, it will be apparent to those skilled in the art that modifications may be made without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the following claims.

100 ... Robot hand 100C ... Control unit 100M ... Memory 101, 101A, 101B, 101C ... Finger 103 ... Base side four-joint link mechanism 104 ... End side four-joint link mechanism 105 ... Palm 106 ... Palm Surface 106V …… Virtual vertical plane 109 …… Wrist 110 …… Actuator 110E …… Encoder 110T …… Transmission device 111 …… Base section 111rh, 121rh …… Reading head 111rm, 121rm …… Reading magnet 111t1, 121t1, 121t2, 131t2 …… Abutment surface 112 …… Middle interphalangeal joint 113 …… Base relay link 114 …… Drive link 114W …… Warm wheel 115 …… Base intermediate link 119 129 …… Virtual link 120 …… Intermediate link Plate 121 …… Middle segment 122 …… Proximal interphalangeal joint 123 …… Terminal relay link 125 …… Terminal intermediate link 131 …… Terminal 132 …… Distal interphalangeal joint 139 …… Fingertips 141, 142… ... Twisting spring 151, 157 ... Transmission shaft 151G ... Transmission gear 151P ... Drive pulley 151W, 157W ... Cylindrical worm 153 ... Transmission belt 154P ... Driven pulley 155 ... Relay gear L1, L2 ... Line component W , W1, W2, W3 ... Work

Claims (7)

A robot hand that has a proximal phalanx on the main body side of the robot hand, a distal phalanx on the fingertip side, and a middle phalanx between the proximal phalanx and the distal phalanx, and functions by transmitting the driving force of one actuator. It ’s a finger drive mechanism.
The intermediate interphalangeal joint that connects the proximal phalanx to the robot hand body in a relative rotatable manner, the proximal interphalangeal joint that connects the proximal phalanx and the intermediate phalanx in a relative rotatable manner, the intermediate phalanx and the terminal phalanx. With a distal interphalangeal joint that connects the relative rotatably,
A drive link that is rotatably connected to the proximal interphalangeal joint at one end and rotated by the actuator, and a group that is rotatably connected to the proximal interphalangeal joint at one end. Both ends are rotatably connected to the side intermediate link, the first connecting shaft arranged on the other end side of the drive link, and the second connecting shaft arranged on the other end side of the base intermediate link. A base-side four-section link mechanism composed of a base-side relay link and
The intermediate phalanx, the distal phalanx, the distal intermediate link rotatably connected to the proximal interphalangeal joint on one end side, and the third connection arranged on the other end side of the distal interphalangeal link. A terminal interphalangeal link mechanism composed of a shaft and a terminal relay link rotatably connected to both ends of a fourth connecting shaft arranged on the other end side of the terminal segment.
It is provided with a posture holding means for holding a predetermined relative posture of the proximal phalanx, the intermediate phalanx and the distal phalanx when no load is applied to the proximal phalanx, the intermediate phalanx and the distal phalanx.
The base-side intermediate link and the end-side intermediate link share one end side while maintaining a relative positional relationship by fixing the distance between the second connecting shaft and the third connecting shaft. Rotatably supported by the proximal interphalangeal joint
The distal phalanx is arranged at three locations where the distal interphalangeal joint, the fourth connecting axis, and the fingertip at a position separated from the intermediate phalanx are different from each other, and the relative positional relationship is fixed .
Further, in the proximal phalanx link mechanism and the distal phalanx link mechanism, the proximal relay link and the distal relay to the proximal phalanx and the intermediate phalanx, which are a part of the length of the finger. Each of the links has the same length and becomes a part of the thickness of the finger. The proximal intermediate link is formed shorter than the driving link, and the distal phalanx is formed from the distal intermediate link. Is also formed short,
In the extended position of the finger, the basal quadruped link mechanism is located on the outside where the second connecting shaft approaches the line between the proximal interphalangeal joint and the first connecting shaft. The distal four-node link mechanism is a finger driving mechanism of a robot hand located on the outside where the fourth connecting shaft approaches the line between the distal interphalangeal joint and the third connecting shaft. As the posture-maintaining means, elastic members urging the proximal interphalangeal joint and the distal interphalangeal joint in a direction of extending the proximal phalanx, the intermediate phalanx, and the distal phalanx are installed in the proximal interphalangeal joint and the distal interphalangeal joint. The finger drive mechanism of the robot hand according to claim 1. The posture-holding means is urged and rotated by the elastic member from a posture in which the proximal phalanx, the middle phalanx, and the terminal phalanx are close to each other toward the extending posture, and then further rotated by the elastic member. The finger driving mechanism of the robot hand according to claim 2, further comprising limiting means for limiting the number of fingers. A detection means for detecting the angle between the members that rotatably support the middle interphalangeal joint, the proximal interphalangeal joint, and the distal interphalangeal joint is provided.
The detection means calculates the angle between the members by using the sensor element that detects the angle between the members, the detection information of the sensor element, and the geometric relationship according to the dimensions of the member that can be acquired in advance. The drive mechanism for a finger of a robot hand according to any one of claims 1 to 3 , which is composed of an arithmetic element. A robot hand having at least two or more pairs of fingers having the drive mechanism according to any one of claims 1 to 4.
A robot hand comprising a transmission mechanism that transmits the driving force of the actuator to the driving link for each finger to function. For each finger, the middle interphalangeal joint, the proximal interphalangeal joint, and the distal interphalangeal joint are positioned in a straight line when no load is applied to the base node and the middle segment, and the fingers are located with each other. The robot hand according to claim 5 , wherein the posture of the distal interphalangeal joint when no load is adjusted to a rotation angle at which the finger pad side of the distal interphalangeal joint can face-to-face contact with the virtual plane when the joints rotate in a direction approaching each other. When the proximal phalanx, the middle phalanx, and the terminal phalanx are brought close to each other on the installation surface of the finger of the robot hand body, the protruding member most protruding in the direction away from the installation surface is at least 3 around the finger. The robot hand according to claim 5 or 6 , which is arranged at or above a location.

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