JPH02279291A - Three finger hand device and operation method - Google Patents

Abstract

PURPOSE:To make it possible to hold a pillar-like work piece selectively and stably both in horizontal way and in vertical way by providing three fingers convertibly in an opposing arrangement in witch one finger and two fingers are opposed to each other and radial arrangement in which three fingers are opposed to each other. CONSTITUTION:A pillar-like work piece is held by three fingers 1, 2, and 3 with each finger joint bent by means of operation actuator. At this time, finger arrangement varies to opposing arrangement attitude, in which two fingers 2 and 3 are arranged so as to opposed to the rest 1, radial arrangement attitude, in which three finger are radially arranged, and pick-up arrangement attitude, in which two fingers are opposed to each other taken by rotationally driving the rotary joints 2C and 3C provided to each of fingers 2 and 3. A work piece 5 is held in a horizontal way in the state of opposing arrangement by actuating each bending joint by means of actuator for operation, and the work piece is held in a vertical way in the state of radial arrangement by bending each bending joint inside.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a three-finger hand device used in a 7" hand unit of a robot, a manipulator, etc., and a method of operating the same.

[Conventional technology]

The above-mentioned conventional three-finger hand device is shown in Fig. 8, and three fingers, that is, first, second, and third fingers a, b, and C, are attached around the palm d. The structure is as follows.

These six fingers a1b, e have first and second joints al, a2°bl, b2. C1+c2, and each has a bending two-degree-of-freedom configuration, and these three fingers a, b, and e move together to perform a grasping operation.

[Problem to be solved by the invention]

In the conventional three-finger hand device described above, six fingers a, b
Since the bending direction of Sc is fixed in one direction, 6 fingers a
,b When the workpiece is gripped by bending the Sc in the opposite direction, it may not be possible to grip it stably depending on the shape of the workpiece, and the arrangement of the three fingers a, b, and c on the palm part d is always 3. Since the two fingers move together to perform the gripping operation to grip the workpiece, it has been impossible to perform a pinching operation by moving only two fingers together.

The present invention was conceived in view of the above, and includes three fingers facing each other in the palm, one finger and two fingers facing each other, and three fingers facing each other radially. By being able to convert into a device with both a radial arrangement and a radial arrangement, for example, it is possible to selectively grip a columnar workpiece in both horizontal and vertical orientations and in a stable state in each orientation.
It is an object of the present invention to provide a three-finger hand device that can perform a pinching operation using two fingers, and a method for operating the same.

[Means to solve the problem]

In order to achieve the above object, the three-finger hand device according to the present invention has first, second, and third fingers that have a plurality of bending joints such as a first and second fingers that can be bent in the same direction. In a three-finger hand device that is attached around the palm, the second and third fingers are rotated relative to the palm on the base side of the first bending joint of two of the three fingers. Swivel joints are provided, and actuators for operation are connected to each of the above joints.

In addition, in the above configuration, both rotation joints are activated to make the two fingers face each other, and when performing a pinching operation with these two fingers, the other fingers are fixed in a position that does not interfere with the pinching operation, and the other fingers are fixed in a position that does not interfere with the pinching operation. The tips of the two operating fingers are fixed in a position in which they can be pinched and actuated, and the pinching operation is performed only with the first bending joints of these two fingers.

[For production]

Each joint of the three fingers is bent by an actuator for operation, whereby the three fingers move together to perform a gripping operation. At this time, by rotating the pivot joints provided on each of the two fingers, the two fingers are placed facing each other in a position facing the other finger, and the three fingers are placed in a facing position. The posture is changed to a radial arrangement posture in which the fingers are arranged radially, and a pinch arrangement posture in which two fingers are opposed to each other. By operating each bending joint with an actuator in the facing arrangement, the workpiece is gripped horizontally, and in the radial arrangement, the workpiece is gripped vertically.

Furthermore, in the state of the knob arrangement, the knob is gripped by two opposing fingers. At this time, the other fingers are fixed in a posture that does not interfere with the above-mentioned pinching operation, and the tips of the two fingers that are to be pinched are fixed in a posture that allows the pinching operation, and the first bending joint of the two fingers is fixed in a position that allows the pinching operation. Perform the pinching operation using the chisel.

〔Example〕

A first embodiment of the present invention will be described based on FIGS. 1 to 4.

In the figure, reference numerals 1, 2, and 3 denote first, second, and third fingers, respectively, which are attached around the palm 4. And the 6 fingers 1, 2.3 have flexion joints la, lb, 2a, 2b, 3
It has a and 3b. Of these, the first bending joint 1a of the first finger 1 is attached to the palm 4, and the first bending joint 2 of each of the second and third fingers 2 and 3 is attached to the palm 4.
a, 3a are the second and third fingers 2, 3, respectively, on the palm part 4;
The palm part 4 via the pivot joints 2c and 3c that pivot relative to the
installed on.

This allows the first finger 1 to move between the first and second bending joints la, l.
There are two degrees of freedom in bending due to b, and the second and third fingers 2,
3 are first and second bending joints 2a, 2b, 3a, respectively.
There are three degrees of freedom: two degrees of freedom for bending 3b and three degrees of freedom for turning due to the pivot joints 2c and 3c.

In the three-finger hand device as described above, the actions of the six fingers 1, 2.3 when trying to grasp workpieces of various shapes are as shown in Fig. 2 (A), (B), and (C). In addition, the arrangement of the second and third fingers 2.3 and the bending directions of the first, second, and third six fingers 1, 2.3 in each of the above actions are shown in FIGS. 3(A) and (B). , as shown in (C).

2(A) and 3(A) show the case where a cylindrical workpiece 5 is held sideways, and the pivot joints 2c, 3c of the second and third fingers 2.3 are held in place by both fingers 2.3. 3 move toward each other, and the second and third fingers 2 and 3 are arranged to face the first finger 1. As a result, the six fingers 1, 2.3 are arranged facing each other, and by bending each joint inward in this state, the workpiece 5 is gripped sideways as shown in FIG. 2(A).

FIGS. 2(B) and 3(B) show a case where a cylindrical workpiece 5 is held vertically, and the pivot joints 2c and 3c of the second and third fingers 2 and 3 are returned to neutral positions. so that the bending directions of the respective bending joints intersect on the palm 4. This allows 6 fingers 1. ．． , 2.3 are in a radial arrangement, and by bending the bending joints of the six fingers 1 and 2.3 inward in this state, the workpiece 5 is gripped vertically as shown in FIG. 2(B). .

FIG. 2(C) and FIG. 3(C) show the case of gripping with two fingers. Working in the opposite direction, both fingers 2.3 x7. Rotate the second and third fingers 2. '3 are arranged so as to face each other. As a result, both fingers 2.3 are placed in a pinch position, and in this state, the second
, the first joints 2a, 1a of the third fingers 2.3 are bent in a direction approaching Li, and the respective second joints 2b are bent.
, 3b in the direction slightly away from the second
As shown in Figure (C), a wire-like workpiece 5' is gripped at a portion beyond the second joints 2b and 3b. At this time, the first finger 1 is bent outward so as not to interfere with gripping the knob.

FIG. 4 shows a specific configuration of the six fingers 1, 2.3 of the above configuration.

Each first flexion joint 1a, 2a of the 6 fingers 1.2.3.

3a is a pair of contraction actuators 6a, 6b, 7a7 for the first joint provided on the proximal end side of each.
Bending operation is achieved by selective contraction of b, 8a, and 8b. Also, each second joint 1b of 6 fingers 1.2.3
, 2b, 3b are two pairs of second joint contraction actuators 9a, 9b, 9a' facing each other on both sides.
9b'1.0a, 1. Ob, 10a', 1. , Ob
', 11 a.

Bending operation is achieved by selective contraction of 1 lb, i ia', and llb'. Furthermore, the first bending joint 2a of the second and third fingers 2.3.

The pivot joints 2c and 3e provided on the proximal end side of the pivot joints 3a each have a pair of pivot joint contraction actuators 1.2a,
It is designed to rotate by selectively contracting 12b, 1.3a, and 13b.

Each of the contraction actuators described above uses a rubber tube type artificial muscle such as McKibben's muscle.

When the internal pressure increases due to the supply of fluid pressure, it expands in the diametrical direction and contracts in the axial direction, and when the internal pressure decreases, it contracts in the diametrical direction and expands in the axial direction.
A plurality of these are used in opposition, and by contracting one and extending the other, the joint can be bent or rotated.

That is, for example, in the first finger 1 in FIG.
By contracting (or extending) one of the pair of contraction actuators 6a and 6b for the first joint and extending (or contracting) the other, the first bending joint 1a is actuated to bend, and the second joint 1b is actuated to bend. If so, contract (or extend) one of the opposing contraction actuators 9a, 9a',
By extending (or contracting) the other contraction actuators 9b, 9b', the second barrier @1b is actuated to bend.

Among the contraction actuators described above, the contraction actuators 6 a and 8 b for the first joint of the first finger 1 are connected to a fluid pressure source 15 via a first pressure control valve 14 .

Furthermore, the contraction actuators 7a, 7b and 8a, 8b for each first joint of the second and third fingers 2.3 are connected to a fluid pressure source 15 via a second pressure control valve 16.

Furthermore, a contraction actuator 9a, 9b for each second joint of the first, second and third fingers 1.2.3.

. . lla' and llb' are each connected to the fluid pressure source 15 via a third pressure control valve 17.

Furthermore, contraction actuators 12a, 12b for the pivot joints of the second and third fingers 2, 3 are provided.

i3a and 1.3b are connected to the fluid pressure source 15 via a pressure control valve 18 for rotation.

The operation of the above configuration will be explained below.

(1) Nigiri mode (a) Opposed arrangement First, the pressure control valve 18 for rotation is used to control the second and third fingers 2.
3 (A
), the second and third fingers 2 and 3 are arranged to face the first finger 1.

Next, the first, second and third pressure control valves 14°1.6,1
．． By contracting the contraction actuator for each joint by 7, each joint of the 6 fingers 1, 2.3 becomes as shown in FIG.
The workpiece 5 is bent in the direction shown by the arrow, and the workpiece 5 is gripped sideways as shown in FIG. 2(A).

The first, second and third pressure control valves 1.4.18°17
By controlling in the opposite direction, the six fingers 1, 2, and 3 are operated to open.

(b) Radial Arrangement First, as shown in FIG. 3(B), the fourth pressure control valve 18 causes the second and third fingers 2.3 to each face toward the center of the palm 4, and the six fingers 1.2 .3 is arranged so that it faces radially.

Next, the first, second and third pressure control valves 14°16.1
By contracting the contraction actuator for each joint by 7, each joint of the 6 fingers 1, 2.3 is bent in the direction shown by the arrow in FIG. 3(B), as shown in FIG. 2(B). The workpiece 5 is gripped vertically.

The first, second, and third pressure control valves 14.1B.

By controlling the finger 17 in the opposite direction, the six fingers 1 and 23 are opened.

(2) Pinch mode First, the pressure control valve 18 for rotation is used to control the second and third fingers 2.
The pair of contraction actuators of each of the rotation joints 2c and 3c of No. 3 are operated in the opposite direction to the above-mentioned "opposing arrangement" to
As shown in Figure (C), the second and third fingers 2 and 3 are arranged to face each other.

Next, the first bending joint 1a of the first finger is bent outward by the first pressure control valve 14 so that the first finger 1 does not interfere with the pinching operation of the second and third fingers 2.3. do it like this. At the same time, the second pressure control valve 16 controls the first and second pressure control valves.
Each second bending joint 1b22 of the second and third fingers 1.2.3
b, 3b are bent outward so that the first finger 1 does not interfere with the pinching action of the second and third fingers 2, 3, and the tips of the second and third fingers 2, 3 are bent outward. Pressure fluid is supplied to the contraction actuators for these second bending joints 2b, 3b so that the knobs are in a suitable position.

Thereafter, the third pressure control valve 17 controls the second and third fingers 2.
．． By bending the first bending joints 2a, 3a of 3 in the direction shown by the arrow in FIG. 3(C), the tips of the second and third fingers 2.3 are bent as shown in FIG. 2(C). A wire-like workpiece 5' is gripped at the part.

In the above embodiment, the first flexion joint 1a of the first finger 1, the first flexion joint 2a of the second and third fingers 2 and 3, and the 38% first
, each second bending joint 1b of the second and third fingers 1 and 2°3,
2b and 3b, the first and second
, an example using the third three pressure control valves 14, 16, and 17 was shown, but rotary switching valves are provided so as to be linked to the pivot joints of the second and third fingers, and the three pressure control valves described above are The number of valves may be one.

The examples are shown below in Fig. 5, Fig. 6 (A), (B), (
The explanation will be based on C). In the description of this embodiment, the same members as those shown in the first embodiment are designated by the same reference numerals, and the explanation thereof will be omitted.

Rotary switching valves 20a and 20b are coaxially attached to the pivoting portions of the pivoting joints 2c and 3c of the second and third fingers 2.3. Both rotary switching valves 20a and 20b each have three positions: an opposing arrangement position a, a radial arrangement position, and a knob arrangement position C. Note that both rotary switching valves 20a.

In 2Ob, since the opposing arrangement position a and the radial arrangement position are the same, they may be the same position.

One contraction actuator 6 of a pair of contraction actuators for the first joint of the 1.2.3 finger 1.2.3
a, 7b, 8b and one pair of contraction actuators 9a, 9a', 1.a, 7b, 8b and contraction actuators for the second joints of the first, second and third fingers 1.2.3. Ob, 10b'
,llb.

11b' is connected to the bow 1=B of the fourth pressure control valve 21, and the other contraction actuator 6b for the first joint of the first finger 1 and the other contraction actuator 6b for the second joint of the first finger 1 are connected to the bow 1=B of the fourth pressure control valve 21. Contraction actuators 9b, 9b1oa, 10a', lla, l
la' is connected to the fourth rotary switching valve 20b via one rotary switching valve 20b.
It is connected to the boat A of the pressure control valve 21 4'i, and is also connected to the drain via the other rotary switching valve 20a. Further, one contraction actuator 8a of the first joint of the third finger 3 is connected to the boat A of the fourth pressure control valve 21. The fourth pressure control valve 21 is designed to continuously control the differential pressure between boats A and B.

FIGS. 6(A), (B), and (C) show how the rotary switching valves 20a and 20b are switched using the cross section of the palm 4 that supports the first, second, and third fingers 1.2.3. Direction and name 1. ,2.
The direction of bending in FIG. 3 is indicated by an arrow, and the operation of this embodiment will be explained below using these figures and FIG. 5.

(+) Nigiri mode <a) Opposing arrangement [Fig. 6 (A)] First, the pressure control valve 18 for turning is used to control the second and third fingers 2,
One contraction actuator of each pair of rotation joints 2c and 3e of 3 is contracted 7, and the other is extended, and the second and third
The fingers 2.3 of the first finger 2.3 are arranged opposite to the first finger 1.

In this state, of the two rotary switching valves 2Oa and 2Ob, the drain of the rotary switching valve 20a of the second finger 2 is closed,
Since the rotary switching valve 20b of the third finger 3 is in a communicating state, the fourth pressure control valve 21 causes the first, second and third fingers 1, 2°3 to move as shown by the arrow in FIG. 6(A). It bends in the direction shown by and performs a gripping operation in the lateral direction as shown in FIG. 2(A).

(b) Radial arrangement [Fig. 6 (B)] First, the pressure control valve 18 for rotation is used to move the second and third fingers 2 and 3 of the palm 4', respectively, as shown in Fig. 6 (B). Arrange the fingers 1 and 23 so that they face radially toward the center.

In this state, both rotary switching valves 2Oa and 20b are arranged in the same way as in the above-described opposing arrangement, so the fourth pressure control valve 21 controls the first, second, and third fingers 12.3 as shown in FIG. 6(B). It bends in the direction shown by the arrow 'C' and operates in the vertical direction as shown in FIG. 2(B).

(2) Pinch mode [Fig. 6 (C)] First, the pressure control valve 18 for rotation is used to control the second and third fingers 2.
The pair of contraction actuators of each of the swivel joints 2c and 3e of No. 3 are operated in a direction opposite to the above-mentioned "opposed position" to move to the sixth position.
As shown in Figure (C), the second and third fingers 2 and 3 are arranged to face the pair.

In this state, the rotary switching valves 20a and 20b are respectively reversed to the above-mentioned "opposing arrangement", and the fourth pressure control valve 2
] Pressure fluid from the third rotary switching valve 20b
After that, the rotary switching valve 20a of the second finger 2 is in a state where it is drained.

In this state, the fourth pressure control valve 21 causes the second and third fingers 1.2 to bend in the direction shown by the arrow in FIG. 6(C) to grasp the knob as shown in FIG. 2(C). Perform the operation.

In addition, at this time, the first and second bending joints 1a of the first finger 1
, lb and the second bending joints 2b of the second and third fingers 2 and 3
, 3b are bent outward by 1r11, and the name finger 1.2.3 becomes as shown in FIG. 2(C).

In the second embodiment, the rotary switching valves 20a and 20b are provided for the second and third fingers 2 and 3, respectively, but as shown in FIG. Alternatively, only the rotary switching valve 20' may be provided.

〔Effect of the invention〕

According to the invention, three fingers 1.2.3 for the palm 4
However, it can be converted into both an opposing arrangement in which one finger 1 and two fingers 2.3 face each other, and a radial arrangement in which the three fingers 1.2.3 face each other radially. For example, it is possible to grip a columnar workpiece selectively in both horizontal and vertical postures and in a stable state in each posture. Furthermore, a pinching action can be performed using the two fingers 2.3, and various gripping actions can be performed.

Furthermore, during the knob grasping operation, fingers that do not participate in the knob grasping operation do not get in the way, and the knob grasping operation can be performed smoothly.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the basic configuration of the present invention, and Figures 2 to 4 are
The figure shows a first embodiment of the present invention, and FIGS. 5 and 6 show a second embodiment of the present invention.
(C) is an explanatory diagram of the operation of six fingers, and Figures 3 (A), (B), (
C) is an operation explanatory diagram showing the arrangement and bending direction of the six fingers, the fourth
Figure 5 is a circuit diagram of a contraction actuator that operates six fingers, Figures 6 (A), (B), and (C) are operation explanatory diagrams showing the switching direction of the rotary switching valve, and Figure 7 is a circuit diagram of a contraction actuator that operates six fingers. FIG. 8 is a circuit diagram showing still another embodiment, and is a diagram illustrating the basic configuration of a conventional example. 1.2.3 are fingers, la, lb, 2a, 2b. 3a and 3b are bending joints, 2c and 3c are rotation joints, 4 is a palm portion, 5 and 5' are workpieces, and 6a and 6b. 7a, 7b, 8a, 8b, 9a, 9b, 9a'9b'
, 10a, 10b, 10a'10b'11a, l
lb, lla', llb', 12a. 12b, 13a, 13b are contraction actuators; 14.
16, 17, 18, 21 are pressure control valves, 15 is a fluid pressure source, and 22a, 22b are rotary switching valves.

Claims (2)

[Claims] (1) In a three-finger hand device in which first, second, and third fingers 12 and 3 having a plurality of bending joints such as a first and second fingers that can be bent in the same direction are attached around the palm portion 4. , the first bending joints 2a, 3a of two of the three fingers
It is characterized in that pivot joints 2c and 3c for pivoting the second and third fingers 2 and 3 relative to the palm 4 are provided on the base side of the hand, and actuators for actuation are connected to each of the above-mentioned joints. A three-finger hand device. (2) When operating both rotation joints 2c and 3c to make two fingers face each other and perform a pinching operation with these two fingers, fix the other fingers in a position that does not interfere with the pinching operation, and 2. The gripper according to claim 1, wherein the tips of the two fingers that perform the pinching operation are fixed in a posture in which the pinching operation is possible, and the pinching operation is performed only with the first bending joints of these two fingers. An operating method for the three-finger hand device.