JPS5959365A - Wrist mechanism of master/slave type manipulator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a f-neck mechanism of a manipulator, and more particularly to a wrist mechanism of a master-slave type manipulator in which the manipulator is operated by an operator operating a mask arm. [Technical Background and Problems] A conventional master-slave type manipulator has a slave arm 1 and a master arm 2, as shown in FIG. and elbow joints 4A and 4B, forearm 5A, 5th, and wrist 6A.

6B, terminal @7A, 7s, slave arm 1
A grasping claw 8 is attached to the terminal shaft 7A, and a handle 9 is attached to the terminal shaft 7B of the master arm 2. When operator 0 operates knob 9, slave arm 1 is driven accordingly. The degree of freedom configuration of this slave arm 1 is as shown in FIG.
A total of 7 degrees of freedom, including the swing rotation P2 of the AiJ arm 5A, the twisting rotation R2 of the forearm 5A, the swing rotation P of the gripping claw 8, the twisting rotation R3 of the gripping claw 8, and the opening and closing G of the gripping claw 3, or the As shown in 21st (b), the entire arm 1 is twisted and rotated, and the upper arm '3
Rocking rotation of A P1 Rocking rotation of forearm 5A P 2 , Forearm 5
Crouching rotation R2 of A, swinging rotation P3 of gripping claw 8, gripping claw 8
It has a total of 7 degrees of freedom including the torsional rotation R3 and the opening/closing G of the gripping claws 8, and the posture and position of the gripping claws 8 can be arbitrarily set by the above-mentioned rocking and twisting rotation. The same applies to the master arm 1.

With such a configuration, normally when the operator IO sets the position and posture of the handle 9, the operating angle of each degree of freedom of the master arm 2 and slave arm 1 is uniquely determined, resulting in stable operation.

However, as shown in FIG. 2(C), the operating strategy of the manipulator is such that the gripping claw 8 is aligned with the forearm 5A at approximately the center L'C of the frequently used operating range.
In this case, the tori rotation angle R2 of the forearm 5A and the gripping claw 8,
R3 is not uniquely determined and becomes extremely unstable. For this reason, the 4-pellator 10 grasps the forearm 5B of the master arm 2 with one hand, preventing its movement, and with the other hand...
You have to operate the handle 9, and the operability is very poor.
4). Therefore, in order to avoid the adverse effects of such singularities, conventionally a configuration has been adopted in which the torsional rotation axis X of the forearm 5A and the swing axis Y of the gripping claw 8 are offset by a distance δ, as shown in FIG. 01. However, even with this configuration, if a large deflection torque is applied to the gripping claws 8 near the singular point, the forearm 5A will be twisted, and the above-mentioned problem could not be solved satisfactorily. Moreover, the above-mentioned offset δ has created a new problem in that it imposes restrictions on the operating range1.On the other hand, as shown in Fig. 3, the FiJ arms 5A and 5B
In the conventional master-slave type manipulator, which is arranged horizontally, even if the TV left camera 1 for photographing the gripping claws 8 is placed at a position Vc18Ii2 corresponding to the operator's 10 eyes, the T
The V left camera 1 is not obstructed by the forearm 5A, and the operator 10 has the advantage of being able to operate the handle 9 very naturally while monitoring the monitor 12. However, in the manipulator with this configuration, because the forearms 5A and 5B are arranged horizontally, the gripping claws 8 and the handle 9 are
13, the above-mentioned drawbacks have become even more serious as the number of uses has increased even further.

[Purpose of the invention]

Therefore, an object of the present invention is to provide a wrist mechanism for a master-slave type manipulator that is free from singularities and can always maintain stable postures of the handle and gripping claws.
Ru.

[Summary of the invention]

To achieve this objective, the present invention provides that the gripping claws -
The holding member that holds the handle is capable of first and second swing rotations about the first and second axes that are orthogonal to each other, respectively, and the holding member is twisted and rotated. a differential gear mechanism that rotates the case in a first swing rotation and a second swing rotation; and a gear transmission mechanism that is held by the case and twists and rotates the holding member; The rotational axis (of the holding part ladle) is made orthogonal to the first axis and the second axis.

[Embodiments of the invention]

An embodiment of the wrist mechanism of the mask slave type manipulator according to the present invention will be described with reference to FIGS. 4 to 6, in which the same parts as those in 1I are denoted by the same reference numerals.

In FIG. 4 showing the external appearance of the skin mechanism of the slave arm, the tips 5a and 5b of the forearm 5A are bifurcated, and between these bifurcated forearm tips 5a and 5b is a cylindrical case 1.
3 is placed. A case 14 supported by the cylindrical case 13 includes a wrist end case 14a and a wrist end cover 14b fixed to the wrist end case 14a. A hand base t5 is rotatably supported on this wrist end cover 14b, and links 16A, 16B are attached to this hand base 15.
A pair of gripping claws 8a and 8b are attached via the .

In FIG. 5 showing the inside of the cylindrical case, the forked forearm tip 5
A shaft 17 passing through a and 5b is rotatably supported by a bearing 18, and a shaft 19 perpendicular to the shaft 17 passes through the center of the shaft 17, the cylindrical case 13, and the wrist end case 14a, respectively. The cylindrical case 13 is rotatably attached to the forked forearm tip 5 via a bearing 20 about a shaft 17.
It is supported by a and 5b.

The wrist end case 14a is rotatably supported by the cylindrical case 13 via a bearing 21 about a shaft 19.

Since the wrist end case 14a is thus supported by the cylindrical case 13, this case 14a can also swing and rotate about the shaft 17. The shaft 17 has a shaft 19f! : A pair of bevel gears 22 and 23 are sandwiched between bearings 24 and 2, respectively.
It is rotatably supported via 5. The bevel gear n.

Sprockets 22a and 23a are fixedly installed at the rear end of the sprockets 22 and 23, respectively, and the bevel gears 22 and 23 have bevel gear forces,
27 are engaged with each other. The bevel gear 26 is rotatably supported on the shaft 19 via a bearing, and the bevel gear 27 is rotatably supported on the outside of the bevel gear 26 by a bearing 4. At the ends of these bevel gears 26 and 27, are spur gears 26a, respectively.

27a is fixedly installed. Coaxial bevel gears 30, 31 are provided on the outer peripheries of the bevel gears 22, 23, and these bevel gears 130, 31 are equipped with bearings (, (2, 33),
(34, :35) rotatably supported around the shaft 17.

In addition, the bevel gears 30 and 31 are respectively Snorrocket 3.
0ae', :Xla are fixed. The bevel gear 36 and bearings 21 and 3 are fixed to the wrist end case 14a.
7, and meshes with the bevel gears 3[] and 31. These bevel gears 1 (1, 31, and 36 constitute a differential wheel mechanism. The bevel gears z2, Otsu, 30
, 31 sprockets 22 a , 23 a ,
, 30a, :31a are meshed with chains 37, 38, 39, and 40, respectively, as shown in FIG. Each of these chains 37, 38, 3
Both ends of 9.40 are connected to a wire rope (not shown) or a metal case, and these wire ropes are driven by an actuator (also not shown) via an elbow joint (not shown).

In FIG. 6 showing the inside of the case 14, the spur gear 2
Spur gears 41°42 mesh with 6a and 27a, respectively.
Both are rotatably supported by 143. This shaft 43 is fixed to the distal end case 14a. Spur gears 44 and 45 mesh with the spur gears 41 and 42, respectively, and a bevel gear 44b is connected to the spur gear 44 via a shaft portion 44a.
is fixed to the other spur gear 15, and a bevel gear 45b75 is connected to the other spur gear 15 via a cylindrical portion 45a into which the shaft portion 44a is inserted. This cylindrical portion 15a is rotatably supported by the wrist end case 14a by a bearing 46, and the shaft portion 44a is rotatably supported by a shaft 47 by a cylindrical portion 45a. The bevel gear 48 meshing with the bevel gear 45b is rotatably supported via the wrist end cover +4bK@ receiver 49. The hand base 15 is fixed to this bevel gear 48. Above gear 2. (,27,7
42, 45, and 48 constitute a gear transmission mechanism that provides torsional rotation to the gripping claws. A shaft 51 passing through the inside of the bevel gear 48 is mounted between the bevel gears meshing with the bevel gear 44b, and this shaft 51 is rotatably supported by the bevel gear 48 by a bearing 52. Further, a goal screw 53 is fixed to the other end of the shaft 51, and the outer periphery of a nut 54 that meshes with this ball screw 53! Protrusions 55 are provided at these locations. Each of the hand paces 15 has a fulcrum bin 56.
, 57 are attached as L-shaped members 58 and 59, respectively. These L-shaped parts! Elongated holes 58a and 59a that engage with the protrusion 55 are provided at one end of each of the protrusions 58 and 59.
is provided on the back, and the other end is a gripping claw 8a from the pins 58b and 59bV.

Connect with 8b. The links 16a, 16b are attached to the hand pace 15 and the respective gripping claws 8a, 8b by means of pins 6Ll, 61, 62, 63, respectively. These L-shaped parts, links, gripping claws (58, I
(ia.

8a) + (59, 16b, +sb) each constitute a parallel link mechanism. In addition, the hand base 15 and the L-shaped member i
j8, 59 and links 16a, +6b are gripping claws 8a, 8
constitutes a holding member that holds b. The center axis of the torsional rotation of this holding member is perpendicular to both the axes 17 and 19, and is determined to pass through the intersection of the two.Next, we will explain the operation of the wrist mechanism of the slave arm according to the present invention. explain.

With 21 independent actuators, each chain 3
9, when driving 40, the sprockets: 30a, :back rotate 1, this Sugerocket 31a,
31 a are both rotated in the same direction, the bevel gear 3 (,
'l, 31 are also rotated in the same direction, and as a result, the bevel gear 36 revolves or oscillates around the shaft 17, so that the handcuff tip case 14a1 handcuff tip cover 14b
1 circular case 13, gripping claws 8a, 8b are integrated 1111
It swings and rotates about 17 in the direction shown by arrow β in FIG. On the other hand, when the Suge rockets 3tJa and 31a are rotated in opposite directions, the bevel gear 36 rotates around the shaft 19, and the case 14 and the gripping claws 8a and 8b are integrally formed.
When the chain is driven by an actuator that swings and rotates in six intersecting directions, that is, in the direction of the arrow α in FIG. 6, the sprocket is rotated. This rotation is caused by the bevel gears 2:', 2'7, spur gears 27a, 42.
l! 5. AM car 45b.

48 to rotate the hand pace 15 as shown by arrow r in FIG. As a result, the gripping claws 8a.

8b rotates, that is, twists.

When the chain 37 is driven by yet another actuator, the gear 22a is rotated, and this rotation is caused by the rotation of the gear wheel 26, spur gear 2b a t 41 + 44
, bevel gears 44b, 50,! 11151, the nut 54 moves straight by rotating the 9" ζ-sill screw 53 by 5 degrees, and the projection 55 on this nut is engaged with the elongated hole ', i8a, 59a. The pair of L-shaped parts 58 and 59 are rotated, and the gripping claws 8a and 8b are driven to open and close in the direction of arrow G in FIG. Since the axis 19 of the second oscillating rotation α and the axis of the torsional rotation 1 are always held perpendicular to each other, the occurrence of the above-mentioned singularity can be prevented and stable operation can always be achieved. .

FIG. 7 shows an embodiment in which the wrist mechanism according to the present invention is applied to a master arm.

71! , 7, V. In place of the hand base 15 in FIG. 6, a handle is fixed to the rear end of the bevel gear 48. The operating lever 61 is swingable around a bin 62 at the lower end of the handle 60, and the long hole 61 of the operating lever 61
A is fitted between the protrusions of the nut 54 of the goal screw 53. The rest of the structure is the same as the wrist mechanism of the slave arm described above.

When the operating lever 61 is swung, the goal screw 53 rotates as the nut 54 moves in a straight line, and this is finally transmitted to the slave arm through a transmission path opposite to that shown in FIGS. 4 to 6. Ru. Similarly, when the handle mark is rotated in the direction of the arrow r, when it is swung in the direction of the arrow β or the arrow α, the information is transmitted through the opposite paths to those in the above-mentioned cases.

〔Effect of the invention〕

As is clear from the description below, according to the present invention, the case, which is swingable and rotatable around two axes υ that are orthogonal to each other, twists and rotates the holding member that holds the grip portion or the handle at 0 T.
Since the center axis of the torsional rotation of this holding member is set perpendicular to the above two axes, the two axes will not rotate during operation.
- It is possible to reliably prevent it from being on a straight line and improve operability. Further, since the swinging rotation of the case in two directions is performed by a differential gear mechanism, and the torsional rotation of the holding member is performed by a gear transmission mechanism, the operation is reliable. Furthermore, if the opening and closing of the gripping claws is also driven by a gear transmission system, a large gripping force can be easily applied to the gripping claws by appropriately selecting the gear ratio. In addition, the three axes mentioned above were concentrated at one point. It is possible to have a wide range of motion during ringing.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram showing an example of a conventional master-slave type manipulator, Fig. 2 is a diagram showing degrees of freedom of each part of the manipulator, and Fig. 3 is a schematic diagram showing another example of a conventional master-slave type manipulator. 4 is a plan view showing one embodiment of the wrist mechanism of the master-slave type manipulator according to the present invention, FIG. 5 is a cross-sectional view showing the inside of the cylindrical case of the above embodiment, and FIG. FIG. 7 is a side view showing an embodiment in which the present invention is applied to a master arm. 8a, 8b...Gripping claw, 14a, 14b--Case, 15, +6, ;'i8, 59...Holding member, 2:(, 27, /I2, .15, 48...Easy wheel transmission mechanism , 3 (+, iru 1, 36...differential gear mechanism, applicant's attorney Kiyoshi Inomata? Figure (b) 433-

Claims (1)

[Claims] (1) The holding member that holds the retaining claw or the handle can perform a first rocking rotation and a second rocking rotation, respectively, about the first axis and the second +lη11 that are orthogonal to each other. together with a case that supports the holding member with zero torsional rotation; a differential wheel mechanism that rotates the case with the four [1st and second swinging rotations; and the holding member held by the case. 1. A wrist mechanism for a master-slave type manipulator, comprising: a gear transmission mechanism for two-twist rotation, the torsional rotation axis of the holding member being orthogonal to the first axis and the second axis. 2 The gear transmission mechanism rotates around the first axis.
'Includes an internal gear, a second bevel gear that meshes with the first bevel gear and rotates around the second rotation, and a gear transmission system that connects the second bevel gear and the holding member described in item 3. A manual rock structure for a master-slave type manipulator according to claim 1, characterized in that: 3. The holding member includes a cylindrical part, and a beer screw connected to the gripping claw or handle is inserted into the cylindrical member.
The hand tffl structure of the master-slave type manipulator according to item 1 or 2.