KR101806002B1

KR101806002B1 - Robotic hand using torsional shape-memory-alloy actuators

Info

Publication number: KR101806002B1
Application number: KR1020160007271A
Authority: KR
Inventors: 김영식; 장태수
Original assignee: 한밭대학교 산학협력단
Priority date: 2016-01-20
Filing date: 2016-01-20
Publication date: 2017-12-07
Also published as: KR20170087360A

Abstract

The present invention comprises a shape memory alloy material wire whose both ends are connected to the respective rotating bodies while being wound in opposite directions on a rotating shaft for hinge-coupling two rotating bodies, The present invention relates to a robot hand using a shape memory alloy rotary actuator showing an operation characteristic similar to a motion of a human hand joint by applying an actuator that generates bidirectional power to the rotary body using a memory effect for each joint.

Description

{ROBOTIC HAND USING TORSIONAL SHAPE-MEMORY-ALLOY ACTUATORS USING SHAPED MEMORY ALLOY ROTATING ACTUATOR}

The present invention relates to a robot hand, and more particularly, to a robot hand comprising a wire of a shape memory alloy material whose both ends are connected to the respective rotating bodies while being wound in opposite directions on a rotating shaft for hinge- A robot hand using a shape memory alloy rotary actuator that exhibits motion characteristics similar to those of a human hand joint by applying an actuator that generates bidirectional power to the rotary body using the shrinkage phenomenon and the initial memory effect, will be.

Robots are mechanical artifacts that have a visual appearance that can perform mechanical movements and behaviors. As the electronics industry develops, technology for robots is also dramatically improved.

Robots that provide such artificial power are designed to perform specific tasks on behalf of or with a person, and in particular, robotic technology is applied in various fields such as medical, industrial, home, etc., It is expected to be used for various purposes in various fields in the future because it can perform specific purposes such as inspection, reconnaissance, and exploration even in difficult environments.

However, since the conventional robot implements the operation characteristic by imitating the body of various animals including the human being, it is focused on the biometric characteristic imitation technique which can freely operate in various environments because the imperfection operation performance is not implemented yet Development is being done.

In particular, in the case of a human hand, it is possible to implement a very wide variety of operations through five fingers, a plurality of joints provided on each finger and the palm, and the robot can be maximally utilized by imitating it. However, in the conventional robot hand, only the operation of letting the thumb and the rest of the fingers pivot or unite can be performed without the finger joint, or even if the robot has the joint, the electric motor is used as the main power source, Shaft and so on, it is mechanically complicated and has a disadvantage in that the weight and volume increase considerably. Thus, it is difficult to realize a flexible and intelligent operation like the hands of a real person because of low power transmission efficiency.

Particularly, for precise individual control of the joints, it is necessary to install individual motors for each joint, which limits the miniaturization of the size and the weight, and there are many troubles for repairing and managing the motors, Complex control circuit and mechanical parts for control are required, which again has the problem of adding maintenance and maintenance difficulties.

Korean Patent Laid-Open No. 10-2012-0040431 (published Apr. 27, 2012)

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and an object of the present invention is to provide a shape memory alloy rotary actuator capable of realizing rotation and restoring operations by using a wire material capable of controlling shape deformation, The present invention is to provide a robot hand using a shape memory alloy rotary actuator capable of realizing the same operating characteristics as a real hand by driving the joints in a compact configuration and facilitating miniaturization and maintenance.

In order to achieve the above object, A first rotating body and a second rotating body coupled to the rotating shaft so as to be rotatable about the rotating shaft; A torque generating unit comprising a wire-shaped shape memory alloy having opposite ends coupled to the first and second rotators, respectively; And a power supply line connected to the rotational force generating unit to supply a current to the rotational force generating unit, wherein each joint is constituted by a rotary actuator, and the first nerve of each finger is connected to the first rotating body constituting the first part of the palm And the second rotating body constituting the first rotating body is coupled through a rotating shaft provided with the second rotating body, thereby constituting a continuous connection structure of the rotating actuator.

In this case, the rotational force generating unit may include a first line formed in a first direction with respect to the rotation axis, a second line formed in a second direction opposite to the first direction with respect to the rotation axis, And an angle between the first rotating body and the second rotating body is controlled through current control of the first line or the second line.

It is preferable that the first rotating body and the second rotating body each include a link mechanism provided at both ends of the insertion hole into which the rotating shaft is inserted.

It is also preferable that each of the fingers is constituted by a plurality of rotors constituting the finger joint so as to be rotatable about the respective rotation axes, and a rotation force generating unit, each of which has a rotary shaft for each joint constituting the finger.

The apparatus may further include a rotating body that constitutes a second portion of the palm by being connected to the first rotating body constituting the first portion of the palm through a rotation axis in the diagonal direction and a rotation force generating portion, It is preferable that the rotating body constituting the first node of the thumb is coupled to the end of the rotating body through the rotating shaft and the torque generating unit.

As the actuator is driven through a shape memory alloy capable of controlling the shape deformation, the vibration and operation noise of the conventional motor driving system can be reduced, the failure rate can be remarkably reduced due to simplification of the control circuit and mechanical parts, Maintenance and maintenance can be achieved easily.

By bi-directionally driving the actuator using the shape memory alloy material, motion of a plurality of joints is individually realized, so that a biometric mimetic technique close to the actual hand motion can be implemented and various application operations can be implemented freely and promptly.

In addition, fine adjustments and smooth movements of the force to individual joints are possible, and the volume of fingers and hands can be reduced with a compact configuration.

1 is an exploded perspective view showing a configuration of a rotary actuator according to the present invention,
2 is a view for explaining the operation principle of a rotary actuator according to the present invention,
3 is a view showing the operation of the rotary actuator according to the present invention,
4 and 5 are perspective views showing the configuration of a rotary actuator according to another embodiment of the present invention,
FIG. 6 is a perspective view showing a configuration of a robot hand according to the present invention,
7 is a perspective view showing the operation of the robot hand according to the present invention.

Hereinafter, the structure of a robot hand using the shape memory alloy rotary actuator of the present invention will be described in detail with reference to the accompanying drawings.

1 is an exploded perspective view showing a configuration of a rotary actuator according to the present invention, FIG. 2 is a view for explaining the operation principle of a rotary actuator according to the present invention, and FIG. 3 is a cross- The rotary actuator according to the present invention includes a rotary shaft 10, a first rotating body 20-1 and a second rotating body 20-2, A rotational force generating unit 30, and a power source line 40. [

The rotation shaft 10 is a rod-like part. The rotation shaft 10 is made of an insulator material which is not limited to a material but can prevent leakage of a current applied to the wire in contact with a shape memory alloy wire to which a current is applied. .

The first rotating body 20-1 and the second rotating body 20-2 are coupled to the rotating shaft 10 so that the angle of the rotating body 10 can be freely adjusted. Each of the rotors 20-1 and 20-2 is provided with a link mechanism 21 that has insertion holes 22 for insertion of the rotary shaft 10 at both ends thereof, The first rotating body 20-1 and the second rotating body can be smoothly rotated and the substrate on which the power line 40 and the rotational force generating unit 30 are electrically connected is connected to the link mechanism 21 It can be seated.

The rotation force generating unit 30 is formed in a wire shape and both ends thereof are coupled to the first rotating body 20-1 and the second rotating body 20-2 while the rotating shaft 10 is wound, So that the angle between the first rotating body 20-1 and the second rotating body 20-2 can be adjusted around the rotating shaft 10.

That is, when one end of the torque generating unit 30 is coupled to the first rotating body 20-1, the other end of the rotating body 10 is rotated at least once, Lt; / RTI > The rotation force generating unit 30 includes a first line 31 that winds the rotation axis 10 in a first direction and a second line that rotates the rotation axis 10 in a second direction opposite to the first direction 32, that is, two wires winding the rotary shaft 10 in different directions.

The first line 31 and the second line 32 are formed of a wire-shaped shape memory material having a shape memory effect such as a shape memory alloy whose shape changes or recovers in accordance with a temperature change due to current supply. This shape memory alloy (SMA) is an alloy made of a polymer material, which is a characteristic of returning to an original shape when heat is applied through an electric current or a high temperature medium even if an object is deformed by an external force Shape memory materials have also been developed, and the shape memory material of the present invention can also include shape memory materials of various materials.

2, the first line 31 and the second line 32 are made of a material capable of exhibiting an elastic restoring force in a state where the rotation axis 10 is wound. When the current flows in the coiled state, it is deformed linearly in the initial state, and is released in the upward direction. At this time, power is generated in a manner similar to the rotation spring.

Since the first and second lines 31 and 32 are wound in opposite directions to each other, the elastic restoring forces of the first line 31 and the second line 32 are the same when the current is not applied, The one rotating body 20-1 and the second rotating body 20-2 are located on the same plane. When a current is supplied to the first line 31 in this state, the first rotating body 20-1 and the second rotating body 20-2 are rotated with respect to the rotating shaft 10 by the contraction of the first line 31 and the memory effect, When the current is supplied to the second line 32, the angle between the first rotation body 20-1 and the second rotation axis 32 is reduced with respect to the rotation axis 10 by the contraction of the second line 32 and the memory effect, The angle between the two rotors 20-2 decreases in the other direction. When the current flow to the first line 31 and the second line 32 is blocked, the first rotating body 20-1 and the second rotating body 20-2 are positioned on the same plane by the elastic restoring force Return to the state. By this operation, the rotary actuator according to the present invention can be driven in both directions.

The power supply line 40 is connected to the torque generating unit 30 to supply current to the torque generating unit 30. [ That is, the power supply line 40 is connected to the first rotating body 20-1 and the second rotating body 20-2 in order to individually supply current to the first line 31 and the second line 32 And are individually connected to the fixed first line 31 and the second line 32. For this, the power line 40 is also connected to the first and second rotors 20-1 and 20-2 in various manners such as soldering or the like through a substrate mounted separately on the first and second rotators 20-1 and 20-2. 2 line 32, respectively.

In the rotary actuator of the present invention as described above, the rotational force is generated by the shrinkage and expansion of the shape memory alloy wire and the linearly changing memory effect in the initial state, whereby the first rotating body 20-1 and the second rotating body 20-2 can be quickly returned to the initial state due to the memory effect, so that the quick operation can be realized. The return speed can also be adjusted by controlling the wire wound in the opposite direction, Control becomes possible.

By using the rotary actuator having the shape shown in FIG. 3, it is possible to control the joints to rotate in both directions unlike a real human hand, so that both hands can be easily realized through the same type of robot hand. For example, by controlling the direction of rotation of each joint of the right hand in the opposite direction, it can be used with the left hand.

FIGS. 4 and 5 are perspective views illustrating the configuration of a rotary actuator according to another embodiment of the present invention. The same principle of rotating using a shape memory alloy as described with reference to FIGS. 1 to 3 is applied, A first line 31 for applying a rotational force in one direction and a spring 33 for returning the first line 31 to an original position without providing two lines 31 and 32 for applying a rotational force to the first line 31. [

In FIG. 4, only two first lines 31 wound around the rotary shaft 10 in the first direction are shown. In FIG. 4, the joints constituting the human hand are bent in only one direction. The number of the first lines 31 shown in the drawing may be appropriately increased or decreased according to the size and required power of the rotating body and may be adjusted along the rotation axis 10 in a direction opposite to the driving direction of the first line 31, The both ends of the spring 33 are connected to the first rotating body 20-1 and the second rotating body 20-2 while the rotating shaft 10 is wound in the second direction opposite to the first direction .

5, the first line is not in the form of winding the rotary shaft 10 but in the state where both ends of the first rotary member 20-1 and the second rotary member 20-2 . At this time, it is preferable to provide a plurality of first lines 31 for stable operation, and similarly, a spring 33 for applying a restoring force in a direction opposite to the driving direction of the first line 31 is provided.

5, since the first line 31 does not sense the rotation axis 10, the rotation axis 10 is positioned at both ends of the first rotation body 20-1 and the second rotation body 20-2 But may be partially formed only in the respective link mechanisms 21 provided. In addition, due to the structure of the first line 31, the first line 31 is extended while the first rotating body 20-1 and the second rotating body 20-2 are expanded, and the radius of the actuator becomes longer It is necessary that a clearance is formed in the connecting portion between the rotary shaft 10 and the link mechanism 21. [ That is, as shown in FIG. 5, the gap between the link mechanism 21 that rotates along the rotary shaft 10 and the rotary shaft 10 is formed through the grooves.

4 and 5, it is possible to form a structure in which each joint rotates only in one direction and does not rotate in the opposite direction like a real human hand, Each hand will have a symmetrical structure.

FIG. 6 is a perspective view showing the configuration of a robot hand according to the present invention, and FIG. 7 is a perspective view showing the operation of the robot hand according to the present invention, showing the configuration of a robot hand using the above- For convenience of understanding, power line and connection method are omitted.

As shown in the figure, the robot hand of the present invention is configured such that a plurality of rotary actuators are continuously connected so as to have the same shape as a human hand, and a single rotary actuator forms each joint of the finger including the palm of the hand, The rotary actuators are connected so as to have the same axial direction so that the finger and a part of the palm can be bent. At this time, the size of the rotating body constituting the rotating actuator and the size of the rotating shaft may be the same, but the size and shape of the rotating body and the rotating shaft of the rotating actuator constituting the palm and each finger are differentiated .

In the preferred embodiment of the present invention, the second rotating body 20-2 constituting the first node of each finger is attached to the first rotating body 20-1 of a relatively large size constituting the first part of the palm, A plurality of rotary actuators are constructed in the form of a continuous structure which is coupled through a rotary shaft 10 provided. 4, the second rotating body 20-2 constituting the first node of the finger is attached to the first rotating body 20-1 constituting the palm of the hand by rotating the rotating shaft 10 And a rotating power generating unit 30 and a power supply line 40 are installed in the first rotating body 20-1 and the second rotating body 20-2 in accordance with the structure and the principle described above, The rotation of the first finger is performed.

At this time, the third rotating body 20-3 constituting the second node of the finger is rotatable through the rotating shaft 10 in the same manner at the end of the second rotating body 20-2 constituting the first node of the finger And a rotating force generating unit and a power supply line are installed in the second rotating body 20-2 and the third rotating body 20-3 to rotate the second finger.

A rotating actuator connection structure having substantially the same structure is applied to the remaining fingers and the same structure and operation characteristics as those of the rotating actuator described above are used because the sizes of the respective joints are different.

In addition, in the accompanying drawings, like the actual human's fingers, a total of three nodes are formed on each finger, and the three joints are constituted by the three rotation axes and the rotational force generating units. However, It is possible to increase or decrease the number of rotary actuators freely.

In this case, when the rotary shaft is coupled to one end and the other end of the link mechanism 21 provided to each of the rotors corresponding to each node of the palm and the finger, a first insertion hole 22 is formed at one end of the link mechanism 21 And the second insertion hole 22 is formed at the other end.

In addition, not only fingers but also palm joints can be implemented in the present invention to realize a more realistic hand gesture. For this purpose, as shown in the accompanying drawings, a rotating body (not shown) for forming a second part of the palm of the hand in a shape similar to the joint of the palm of the human hand in the direction of the lower thumb of the first rotating body 20-1 constituting the first part of the palm 20-5 are diagonally connected via a rotation shaft and rotation is performed between the rotating body 20-1 forming the first portion and the rotating body 20-5 forming the second portion through the rotating force generating portion do.

In this case, the width of the rotary actuator constituting the palm joint is inevitably greater than that of the rotary actuator constituting the joint of the finger, and the length of the rotary shaft provided becomes relatively longer. Therefore, It is also possible to increase the number of the wire wires constituting the rotational force generating portion relative to the actuator to four, six, or the like.

Since the rotating body 20-5 constituting the second portion of the palm is provided, the rotating body constituting the first palm of the thumb is separately provided at the end of the rotating body 20-5 constituting the second portion of the palm Through the rotation shaft and the rotation force generating unit of the motor.

In a preferred embodiment of the present invention, the palm portion of the robot hand is divided into a first portion and a second portion to constitute a rotary actuator. However, if necessary, the palm portion can be divided into more portions, And a robot hand in which the palm joint and the finger joint are realized by continuously connecting the plurality of rotary actuators having different sizes is controlled to control the current supply to each rotary force generating unit 30, As a result, it is possible to more completely reproduce the operating characteristics of the real human's hand.

It is to be understood that the invention is not limited to the disclosed embodiment, but is capable of many modifications and variations within the scope of the appended claims. It is self-evident.

10:
20-1: First Whole 20-2: Second Whole
20-1 to 20-N: First to Nth rotating bodies 21: Link mechanism 22:
30: rotational force generating part 31: first line 32: second line
33: spring
40: Power line

Claims

A rotary shaft (10);
A first rotating body 20-1 and a second rotating body 20-2 coupled to the rotating shaft 10 so as to be rotatable about the rotating shaft 10;
A torque generating portion 30 composed of a wire-shaped shape memory alloy whose both ends are coupled to the first rotating body 20-1 and the second rotating body 20-2, respectively;
And a power supply line (40) connected to the rotational force generating unit (30) and supplying current to the rotational force generating unit (30), wherein each joint is constituted by a rotary actuator,
The first rotating body 20-1 constituting the first part of the palm is coupled to the second rotating body 20-2 constituting the first node of each finger via the rotating shaft, Structure,
The first rotating body 20-1 and the second rotating body 20-2 each include a link mechanism 21 provided at both ends of the insertion hole 22 into which the rotating shaft 10 is inserted And a robot hand using the shape memory alloy rotary actuator.

The method according to claim 1,
The rotation force generating unit 30 includes a first line 31 formed in a first direction with respect to the rotation axis 10 and a second line 31 formed in a second direction opposite to the first direction with respect to the rotation axis 10, And a spring (33) to which a restoring force acts, as opposed to the operating direction of the line (32) or the first line (31)
Wherein the angle between the first rotating body (20-1) and the second rotating body (20-2) is controlled through current control of the first line (31) or the second line (32) Robot Hand Using Memory Alloy Rotary Actuator.

delete

The method according to claim 1,
Characterized in that each finger is constituted by a plurality of rotors constituting a finger joint so as to be rotatable around each rotary shaft (10) and a torque generating unit, each of the joints constituting the fingers being provided with a rotary shaft (10) Robot Hand Using Rotary Actuator.

The method according to claim 1,
Further comprising a rotating body connected to the first rotating body (20-1) constituting the first part of the palm of the hand through a diagonal rotating shaft and a rotating force generating part to constitute a second part of the palm,
Wherein the rotating body constituting the first node of the thumb is coupled to the end of the rotating body constituting the second part of the palm of the hand by the rotating shaft and the rotating force generating unit.