JPH0540956Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Field of Industrial Application The present invention relates to a master arm that is capable of following the complicated movements of a worker.

B. Overview of the invention The present invention is a master arm that organically combines a large number of joints, allowing it to take complex postures that could not be taken with conventional master arms, and with good operability.

C. Prior Art Manipulators are frequently used to work in various environments. There are various operating methods for such a manipulator, one of which is a master-slave operating method in which the manipulator is operated by the movement of a master arm operated by an operator.

As shown in FIGS. 6a and 6b, the master arm 1 used in the master-slave type manipulator has an upper arm 2 and a forearm 3 connected through a joint, and a master arm 1 is provided at the tip of the forearm 3. When the worker P grasps and operates the grip 4, the grip 4 moves according to the movement of the worker's P arm.

D Problems to be solved by the invention By the way, in the prior art shown in Fig. 6, the worker P
The postures that can be taken are restricted, and it is not possible to easily take various complicated postures. Furthermore, in the conventional master arm, if the shoulder, elbow, and wrist are extended in a straight line, the elbow cannot be bent simply by pulling back the grip 4, making it difficult to operate.

Typical postures include elbow down, elbow side, and elbow up. Elbow-down is a posture in which the elbow joint is lower than the shoulder joint, and is taken when working, such as putting one's hand under a person's desk. Also,
Elbow side is a position where the elbow is stretched out to the side, such as the position the left arm takes when writing with the right arm at a desk. Elbow up is a posture where the shoulders and elbows are at the same height and the hands are extended directly below the elbows. Of course, in reality, there are also postures that are a combination of the above three postures.

Generally, in a master-slave manipulator, the important thing about the joint structure of the master arm is that it must be light and easy to operate. Moreover, a manipulator that performs dexterous work cannot perform a variety of tasks unless it is equipped with multiple joints. In this case, it is desirable to operate the multi-jointed joints at will only with the grip part of the master arm. For example, connecting other parts such as elbows and shoulders to the master is extremely difficult and tiring. Undesirable. Furthermore, since the weight of the master arm itself must not become a burden on the worker, a method that balances the weight of the master arm is preferable. Although it is possible to calculate this self-weight balance from the motor and joint angles and control it electrically, it is better to balance it mechanically as much as possible in order to make the device smaller and easier to operate. desirable.

In view of the above-mentioned prior art and general requirements, the present invention provides a master arm whose posture can be changed depending on work, and whose own weight can be balanced in any posture.

E. Means for Solving the Problems The present invention that solves the above problems consists of a shoulder part with three degrees of freedom, an arm part in which the rotation angle of the elbow joint is regulated within a certain range, and three degrees of freedom. It is characterized by a gripping wrist and a balance weight that mechanically balances the master arm.

F. Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a plan view showing an embodiment of the present invention, and FIG. 2 is a front view thereof. As shown in the figure, the pillar 10
The first shoulder joint 21, which is supported by and projects forward, rotates in a vertical plane as shown by arrow A. 1st shoulder joint 2
1, a second shoulder joint 21 rotates in a vertical plane perpendicular to the vertical plane of rotation of the first shoulder joint 21, as shown by arrow B.
A shoulder joint 22 is provided, and at the tip of the second shoulder joint 22 there is a third shoulder joint that rotates in a horizontal plane as shown by arrow C.
A shoulder joint 23 is provided. These three shoulder joints 21, 22, and 23 form a shoulder portion 20. And shoulder joints 21 and 23 as necessary,
It is possible to apply the brakes on either one or both at the same time. As will be described in detail later, this allows the shoulder 20 to be stabilized just by grip operation.
can be operated.

The upper arm 31 has its proximal end supported by the third shoulder joint 23. At the tip of the upper arm 31, an elbow joint 32 is provided that rotates in a horizontal plane as shown by arrow D. Although details will be described later, the rotation angle of the elbow joint 32 is regulated within a certain range. Further, the base end of the forearm 33 is supported by the elbow joint 32. And upper arm 3
1, an elbow joint 32, and a forearm 33 form an arm portion 30.

At the tip of the forearm 33, a first wrist shoulder joint 41 that rotates in a vertical plane as shown by an arrow E is provided.
At the end of the first wrist joint 41, there is provided a second wrist joint 42 that rotates in the horizontal plane as shown by arrow F, and at the end of the second wrist joint 42, there is provided a second wrist joint 42 that rotates in the vertical plane as shown by arrow G. A third wrist joint 43 is provided that rotates at . As shown in FIG. 3, the three wrist joints 41, 42, and 43 are arranged so that the extension lines of the rotation axes of each joint intersect at a point H in space. The grip 44 is rotatably supported by the third wrist joint 43, and the grip 44 includes a switch 4.
5,46 are attached. During actual operation,
When the grip 44 is gripped by the fingers of the worker P, the ankle of the worker P's wrist is located near point H. Therefore, the grip 44 can be oriented in all directions that can be stretched with human hands, such as up and down, left and right, and diagonally.

In the master arm of this example, Figs.
The posture shown in the figure is the standard posture.
In this position, it is easiest to operate the wrist in any direction, such as extending or retracting, up and down, left and right. In this reference posture, the first shoulder joint 21 and the third wrist joint 43 are coaxial, and the grip 44 is located on a line connecting both joints 21 and 43. Further, the line connecting the joints 21 and 43 and the line connecting the joints 41 and 42 are perpendicular to each other. joint 3
The angle formed by the line connecting 2 and 42 and the upper arm 31 is γ
Then, in the standard attitude, the angle γ is approximately 90°,
This angle may be changed somewhat depending on the application. angle γ
If the angle is 90°, the shape connecting the joints 23, 32, and 42 will be approximately an isosceles triangle, but if the length of the upper arm 32 is made slightly larger than the length between the joints 32 and 42, the length of the human arm will be the same. The ratio may be changed somewhat depending on the purpose, such as making it proportional to the amount of water. Furthermore, in the standard posture, the angle θ between the line connecting point H and the elbow joint 32 and the axis of the first wrist joint 41 is about 45°, and can be changed depending on the purpose.

Among the above-mentioned joints, the rotation angle of the elbow joint 32 is regulated within a certain range. That is, the elbow joint 32 is adjusted so that the angle γ is within a range of approximately 170° or less and approximately 20° or more.
The rotation angle is regulated. Although details will be described later, this allows the grip 44 to be easily moved back and forth.

Furthermore, four balance weights 5 are used in this embodiment.
1, 52, 53, and 54. The first balance weight 51 is provided at the elbow joint 32, balances the weight of parts beyond the elbow joint 32, such as the forearm 33 and wrist 40 (its center of gravity is W), and is opposed to the center of gravity W. is in a position to do so. Second
The balance weight 52 is provided at the third shoulder joint 23 and balances the weight of parts located ahead of the third shoulder joint 23, such as the arm 30, the wrist 40, and the first balance weight 51. The third balance weight 53 is provided at the second shoulder joint 22,
The weight is balanced with the portion beyond the second shoulder joint 22. The fourth balance weight 54 is provided at the first shoulder joint, and balances the weight of the portion beyond the first shoulder joint 21. Since the balance weights 51, 52, 53, and 54 are provided in this way, the weight balance of the joints 21, 22, 23, and 32 is maintained, and they can be operated very lightly. Although the weight of the wrist joints 41 and 42 is not balanced, since the weight of these parts is light, there is no problem in operation.

In the master arm with the above configuration, each joint is equipped with at least an operating angle sensor (potentiometer or encoder, etc.), and if necessary, a drive mechanism such as a motor and a reducer to assist with reaction force and self-weight balance is attached. do. For these, known techniques may be used as they are. Furthermore, if necessary, a torque detector can be installed, and controls for reducing operating force, overload protection, etc. can be selected and adopted as appropriate.

Next, the operation of this embodiment will be explained.

FIG. 4 shows the master arm fully extended by pressing the grip 44. At this time, the degree of opening of the elbow joint 32 is maximum, and the maximum degree of opening angle γ ₁ is normally 150°, but depending on the application, it is preferably about 170° at the maximum. Since the maximum opening angle γ ₁ is the value mentioned above, by simply holding the grip 44 and pulling it toward the shoulder 20 from the state shown in FIG.
can be bent. When the master arm is fully extended, the wrist portion 40 forms an angle of α ₁ . In this embodiment, the angle α ₁ is approximately 30°, and even in this state, by interlocking with the second wrist joint 42,
You can move your wrist up and down relatively naturally.

FIG. 5 shows the grip 44 pulled fully toward the shoulder 20. At this time, the opening degree of the elbow joint 32 becomes the minimum, and the minimum opening angle γ ₂ is approximately 20°.
~30°. If the angle γ ₂ is smaller than this, the operator P's hand will be caught between it and the shoulder portion 20, and if it is larger, the operating range in the front-back direction will be reduced. Therefore, the above angle is appropriate for the minimum opening angle γ ₂ .

As shown in FIGS. 4 and 5, the grip 44
When moving forward and backward, joints 23, 32, 42
operate in synchrony. At this time, since the angle γ is regulated as described above, operability is good.

Next, each operation when the master arm is close to the reference posture will be explained. Twisting of the grip 44 can be handled only by rotating the third wrist joint 43. Swinging the wrist up and down can be handled by only rotating the first wrist joint 41. When swinging the wrist from side to side, the second wrist joint 4
This can be done with only 2 rotations. When swinging the arm from side to side around the shoulder, it is possible to do so by only rotating the third shoulder joint 23. Swinging the arm up and down around the shoulder can be done by only rotating the second shoulder joint 22. Twisting the arm around the shoulder can be done by only rotating the first shoulder joint 21. In this way, since each movement can be handled by rotating only one joint, stable operation is possible.

In this embodiment, as shown in FIG. 1, the first shoulder joint 21 and the second wrist joint 43 are coaxially located in the reference posture, so that in normal operation, the shoulder joint 21
is fixed, and the twisting of the grip 44 is handled by the wrist joint 43. Then, the shoulder joint 21 is made movable only when necessary, and the upper arm 31 or the like is lifted electrically or manually to rotate the shoulder joint 21 by a predetermined angle, and then the shoulder joint 21 is fixed again. The subsequent work is carried out using only the grip 44. Note that driving and fixing the shoulder joint 21 electrically, or fixing and releasing it manually can be easily achieved by applying known techniques.

Although the first shoulder joint 21 is normally fixed and seems unnecessary at first glance, it actually has the following great effects. As mentioned above, Figure 1 shows a state in which the elbows are stretched out to the sides. From this posture, even if applied to a symmetrical two-arm manipulator, it is possible to operate the manipulator with both arms tightly against a standing tree. , it is not possible to operate a horizontal rod or piping in a way that requires lifting it up with two arms. To achieve such a motion, the joint 21 is operated 90 degrees, and one arm, for example, the right arm, rotates the shoulder joint 21 so that the elbow joint 32 is above the hand (elbow up posture). Next, the other left arm rotates the shoulder joint 21 so that the elbow joint 32 is below the shoulder. (Elbow down posture) Then elbow joint 3
2, it becomes possible to swing vertically and hold a horizontal rod-shaped object.

Therefore, this intermediate posture is also possible, and a master arm can be created in which the arm can operate in many forms, including the posture that a human would take with the upper body tilted.

Here, we have explained the case where the shoulder joint 21, which usually occurs often, is fixed, but depending on the work, the wrist joint 4
It is also possible to fix the shoulder joint 3 and operate the shoulder joint 21 in conjunction with the grip 44.

A switch 45 and a lever switch 46 are arranged around the grip 44 as shown in FIG.
Although the master does not have it, it is easy to make commands to open and close the fingers of the slave, or to rotate or fix the shoulder joint 21 as the case may be, using conventional techniques.

In this case, each joint of the master arm is equipped with at least an angle detector (for example, a potentiometer or an encoder) as a signal generator to operate the slave, and the reaction force from the slave side is transmitted to the operator. It is conventional to attach a drive device such as a motor to a joint that performs bilateral control to transmit information to the robot.

G. Effects of the invention As specifically explained above with the embodiments, the invention provides the following effects.

(b) No matter how much the upper arm and forearm move relative to the first shoulder joint, the body's own weight is balanced and the operation is light.

(b) No matter how much the first shoulder joint is rotated, the body's weight balance will not be lost. Therefore, it is possible for a human being to maintain a typical working posture with the elbows stretched out to the side, or with the elbows up or down. It can accommodate a variety of arm postures. In other words, it becomes a dexterous master arm that can follow any human arm movement.

(c) Important movements such as swinging the arm vertically and stretching the arm horizontally can be performed stably by rotating only one joint;
Work becomes smoother.

(d) It can handle dexterous work such as swinging the worker's wrist vertically, horizontally, and diagonally.

(E) Since the rotation angle of the elbow joint was restricted to a certain range,
Even when the master arm is fully extended, the elbow joint can be bent by simply pulling the grip, improving operability.

[Brief explanation of the drawing]

Fig. 1 is a plan view showing an embodiment of the present invention, Fig. 2 is a front view showing the embodiment, Fig. 3 is a perspective view showing the wrist portion of the embodiment, and Figs. FIG. 6 is an explanatory diagram showing the operating state, and FIG. 6 is an explanatory diagram showing the prior art. In the drawing, 10 is a support, 20 is a shoulder, 21, 2
2, 23 are shoulder joints, 30 are arm parts, 31 are upper arms, 3
2 is the elbow joint, 33 is the forearm, 40 is the wrist, 41,
42, 43 are wrist joints, 44 are grips, 51,
52, 53, and 54 are balance weights, and P is a worker.

Claims (1)

[Claims for Utility Model Registration] The first member is supported by a support member and rotates in a vertical plane
The shoulder joint and the first shoulder joint are provided at the tip of the first shoulder joint.
Rotation of Shoulder Joint A shoulder portion having a second shoulder joint that rotates in a vertical plane perpendicular to the vertical plane, and a third shoulder joint that is provided at the tip of the second shoulder joint and rotates in a horizontal plane. , an arm portion having an upper arm whose base end is supported by a third shoulder joint, an elbow joint provided at the distal end of the upper arm and rotates in a horizontal plane, and a forearm whose base end is supported by the elbow joint; A first wrist joint provided at the tip of the forearm and rotates in a vertical plane, a second wrist joint provided at the tip of the first wrist joint and rotated in a horizontal plane, and a second wrist joint provided at the tip of the second wrist joint. a third wrist joint that rotates in a vertical plane, and is arranged so that extension lines of the rotation axes of the first, second, and third wrist joints intersect at one point; A first balance weight that is provided at the elbow joint and balances the weight of the portion beyond the elbow joint, and a second balance weight that is provided for the third shoulder joint and balances the weight of the portion that is beyond the third shoulder joint. a third balance weight that is provided on the second shoulder joint and balances the weight of the part beyond the second shoulder joint, and a third balance weight that is provided on the first shoulder joint and balances the weight of the part beyond the first shoulder joint. It has a fourth balance weight that balances the weight of the tip, and the angle between the line connecting the second wrist joint and the elbow joint and the upper arm is approximately 170° or less and approximately 20° or more. The master arm is characterized by a regulated rotation angle of the elbow joint.