KR102478624B1 - Spring­like Pneumatic Artificial Muscle and Operation method thereof - Google Patents

Abstract

The present invention relates to a pneumatic artificial muscle unit using elastic energy and an operating method thereof, and more particularly, to a pneumatic artificial muscle unit comprising: an inelastic sleeve that contracts and expands in a longitudinal direction; a gas injection unit connected to one end of the non-elastic sleeve to inject gas; an exhaust valve connected to the other end of the inelastic sleeve and through which gas introduced into the inelastic sleeve is exhausted in an exhaust mode; a tension spring provided between the gas injection part and the exhaust valve in the non-elastic sleeve; and an elastic tube within the non-elastic sleeve, one end of which is connected to the gas injection part and the other end of which is connected to the exhaust valve, and when gas is injected through the gas injection part, it is supplied into the elastic tube and expands, and the elastic tube is expanded. It relates to a pneumatic artificial muscle unit using elastic energy, characterized in that elastic energy is stored by expansion of the tube and the elastic energy is stored in the tension spring by expanding the non-elastic sleeve in the longitudinal direction.

Description

Pneumatic artificial muscle unit using elastic energy and its operation method {Springlike Pneumatic Artificial Muscle and Operation method thereof}

The present invention relates to a pneumatic artificial muscle unit using elastic energy and an operating method thereof.

Recently, various researches and developments have been conducted on rehabilitation or activity assistive devices for the elderly or disabled, and as an assistive device for rehabilitation or activity assistance for the elderly or disabled, who have difficulty in moving joints such as arms or legs, wearable muscle strength Development of support robots is also in progress.

In the case of human body wearable muscle support robots developed so far, the wearable part has a structure consisting of a link and a joint, and is manufactured in a form in which a motor is attached to the joint or a pneumatic piston or artificial muscle is attached to the link. That is, in order to support each joint of the user's body structure, a link structure in which frames of hard material are connected is applied, and a driving mechanism such as a driving motor for artificially driving each joint is applied. Therefore, the driving force of the driving unit is transmitted to each link, and the user's rehabilitation or activity is assisted by operating the joint to which the link is fixed.

However, in the case of the human body wearable muscle strength support robot through the link structure as described above, energy consumption of the drive unit increases due to the weight of the linkage structure, and due to the complex structure, inconvenience and manufacturing cost increase. In addition, it is difficult to easily change to suit the user's body structure.

In addition, in robots that frequently interact with people, such as wearable robots and collaborative robots, safe driving technology is indispensable and is being actively researched. As a representative safe actuator, pneumatic artificial muscles are widely studied due to their light, flexible properties and high force density.

However, since the pneumatic artificial muscle uses air, which is a compressible fluid, it has a characteristic of very slow response. In particular, in the case of wearable robots, if the pneumatic artificial muscles are slower than the muscles of a person who jumps or runs and cannot be controlled, they act as a load on people and become a major obstacle in assisting or interacting with people's rapid motion.

In addition, in contrast to human muscles that can contract up to 70% (+-35%), pneumatic artificial muscles generally have a contraction ratio of 25% and thus have limited displacement characteristics.

This acts as a stumbling block that greatly limits the degree of freedom of wearable/collaborative robots. Therefore, it was necessary to develop a new spring-like PAM technology that can improve the low response and contraction ratio of pneumatic artificial muscles.

Korean Registered Patent No. 10-1566758 Korean Registered Patent No. 10-2177307 Korean Registered Patent No. 10-1864583 Korean Registered Patent No. 10-1563105

Therefore, the present invention has been made to solve the above conventional problems, and according to an embodiment of the present invention, unlike general contraction type pneumatic artificial muscles, when the pneumatic artificial muscles are stretched in the longitudinal direction, they have the characteristics of a tension spring. Pneumatics using elastic energy can dramatically improve responsiveness by using the fast response property of the passive element for driving when pneumatic artificial muscles can store a large amount of elastic energy and use the stored elastic energy for compression drive. Its purpose is to provide an artificial muscle unit and its operating method.

And according to an embodiment of the present invention, elasticity that can generate very fast and strong contraction force / contraction ratio by using a strong tension spring, an elastic tube, and an exhaust valve operated by motion of a person or robot for a large force of the actuator. Its purpose is to provide a pneumatic artificial muscle unit using energy and an operating method thereof.

According to an embodiment of the present invention, the tension spring and the highly elastic tube expand from the pressure energy of the air to store elastic energy, limit the expansion of the radius from the outer non-elastic sleeve made of non-elastic material, and the part that is folded in the form of an origami in the longitudinal direction. When the exhaust valve is opened as the exhaust valve is opened as the inner wire that limits tension is pulled, the air is rapidly exhausted, and the elastic energy is immediately converted into kinetic energy, resulting in quick response and high contraction ratio/ Its purpose is to provide a pneumatic artificial muscle unit using elastic energy capable of realizing high contractile force and an operating method thereof.

According to an embodiment of the present invention, a tension spring with a high contraction ratio, a high elasticity tube, and a motion-triggered exhaust valve that can dramatically improve the exhaust speed provide high responsiveness and elastic energy with a high contraction ratio / high contraction force. The purpose is to provide a pneumatic artificial muscle unit and its operation method using.

On the other hand, the technical problems to be achieved in the present invention are not limited to the above-mentioned technical problems, and other technical problems that are not mentioned will become clear to those skilled in the art from the description below. You will be able to understand.

A first object of the present invention is a pneumatic artificial muscle unit comprising: an inelastic sleeve that performs contraction and expansion movements in the longitudinal direction; a gas injection unit connected to one end of the non-elastic sleeve to inject gas; an exhaust valve connected to the other end of the inelastic sleeve and through which gas introduced into the inelastic sleeve is exhausted in an exhaust mode; It can be achieved as a pneumatic artificial muscle unit using elastic energy, characterized in that it includes; and a tension spring provided between the gas injection unit and the exhaust valve in the non-elastic sleeve.

Further, an elastic tube having one end connected to the gas injection unit and the other end connected to the exhaust valve may be further included in the non-elastic sleeve.

In addition, when gas is injected through the gas injection unit, it is supplied into the elastic tube and expanded, elastic energy is stored by the expansion of the elastic tube, and the inelastic sleeve expands in the longitudinal direction to store elastic energy in the tension spring that can be characterized.

In addition, a plurality of the elastic tubes or tension springs may be arranged in parallel to increase the force of the actuator, and may be installed to be slack in stages to design an actuator having variable rigidity.

And it may further include a trigger means for opening the opening/closing member in the exhaust valve when the inelastic sleeve reaches a set expansion length.

In addition, the trigger means includes a wire having one end fixed to the gas injection unit and the other end fixed to the opening/closing member, and when the inelastic sleeve reaches a set expansion length, the wire is tensioned to open and close the opening/closing member. It may be characterized in that it is operated to open.

The exhaust valve may further include a compression spring for applying a restoring force to close the opening and closing member when the wire is not in a tension state.

In addition, the inelastic sleeve may be characterized in that the deformation in the radial direction is limited and configured to contract and expand in the longitudinal direction.

And the inelastic sleeve may be characterized in that it is configured in the form of a corrugated pipe.

A second object of the present invention is a method for operating a pneumatic artificial muscle unit, comprising: a first step of injecting gas through a gas injection unit connected to one end of an inelastic sleeve that undergoes contraction and expansion movements in the longitudinal direction; a second step of supplying and expanding gas into the elastic tube in the non-elastic sleeve, and storing elastic energy by the expansion of the elastic tube; and a third step of expanding the non-elastic sleeve in the longitudinal direction to store elastic energy in the tension spring.

In addition, the non-elastic sleeve may be expanded in the longitudinal direction while limiting expansion in the radial direction by the expansion of the elastic tube.

In addition, a fourth step of opening the exhaust valve to exhaust gas and simultaneously converting the elastic energy of the elastic tube and the elastic energy of the tension spring into kinetic energy to contract and compress the inelastic sleeve in the longitudinal direction. can be characterized.

In the fourth step, when the inelastic sleeve reaches a set expansion length, the opening/closing member in the exhaust valve is opened by a trigger means.

In addition, the trigger means includes a wire having one end fixed to the gas injection unit and the other end fixed to the opening/closing member, and when the inelastic sleeve reaches a set inflation length, the wire is tensioned to break the opening/closing member. It may be characterized in that it is operated to open.

According to the pneumatic artificial muscle unit using elastic energy and its operating method according to an embodiment of the present invention, unlike general contraction-type pneumatic muscles, when the pneumatic artificial muscle is stretched in the longitudinal direction, the pneumatic artificial muscle having the characteristics of a tension spring It is possible to store a large amount of elastic energy, and when the stored elastic energy is used for compression driving, the fast response property of the passive element is used for driving, which has the effect of dramatically improving responsiveness.

And according to the pneumatic artificial muscle unit using elastic energy and its operating method according to an embodiment of the present invention, a strong tension spring, an elastic tube, and an exhaust valve operated by the motion of a human or robot are used for a large force of the actuator. Thus, it has the effect of producing a very fast and strong contraction force/contraction ratio.

According to the pneumatic artificial muscle unit using elastic energy and its operating method according to an embodiment of the present invention, the tension spring and the highly elastic tube expand from the pressure energy of the air to store elastic energy, and the radius from the outer inelastic sleeve made of inelastic material. When the exhaust valve is opened as the inner wire limiting tension is pulled, the elastic energy is stored as maximum as the part folded in the form of an origami is stretched in the longitudinal direction and the air is rapidly exhausted, and the elastic energy is immediately exhausted. As energy is converted into kinetic energy, it has the effect of realizing fast response and high contraction ratio/high contraction force. In addition, variable stiffness can be realized through the parallel arrangement of a plurality of elastic materials in stages.

According to the pneumatic artificial muscle unit using elastic energy and its operating method according to an embodiment of the present invention, a tension spring having a high contraction ratio, a highly elastic tube, and a motion-triggered exhaust valve that can dramatically improve the exhaust speed It has the effect of having high responsiveness and high shrinkage ratio/high shrinkage force.

On the other hand, the effects obtainable in the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below. You will be able to.

The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the invention serve to further understand the technical idea of the present invention, the present invention is limited only to those described in the drawings. and should not be interpreted.
1 is a cross-sectional view of a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention;
2 is a flowchart of a method of operating a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention;
3 is a cross-sectional view of a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention at the start of gas injection;
Figure 4 is a cross-sectional view of a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention in the expansion and tension step;
5 is a cross-sectional view of a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention in an exhausting step;
6 is a cross-sectional view of a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention in contraction and compression stages;
7a is a cross-sectional view of a closed exhaust valve according to an embodiment of the present invention;
7B is a cross-sectional view of an open exhaust valve according to an embodiment of the present invention;
8a is a schematic diagram showing a state in which a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention is worn on the hip side;
Figure 8b is a schematic diagram showing a pneumatic artificial muscle unit using elastic energy according to the embodiment of the present invention expanded and stretched in Figure 8a.

The above objects, other objects, features and advantages of the present invention will be easily understood through the following preferred embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content will be thorough and complete and the spirit of the present invention will be sufficiently conveyed to those skilled in the art.

In this specification, when an element is referred to as being on another element, it means that it may be directly formed on the other element or a third element may be interposed therebetween. Also, in the drawings, the thickness of components is exaggerated for effective description of technical content.

Embodiments described in this specification will be described with reference to cross-sectional views and/or plan views, which are ideal exemplary views of the present invention. In the drawings, the thicknesses of films and regions are exaggerated for effective explanation of technical content. Accordingly, the shape of the illustrated drawings may be modified due to manufacturing techniques and/or tolerances. Therefore, embodiments of the present invention are not limited to the specific shape shown, but also include changes in the shape generated according to the manufacturing process. For example, a region shown at right angles may be rounded or have a predetermined curvature. Accordingly, the regions illustrated in the drawings have attributes, and the shapes of the regions illustrated in the drawings are intended to illustrate a specific shape of a region of a device and are not intended to limit the scope of the invention. Although terms such as first and second are used to describe various elements in various embodiments of the present specification, these elements should not be limited by these terms. These terms are only used to distinguish one component from another. Embodiments described and illustrated herein also include complementary embodiments thereof.

Terminology used herein is for describing the embodiments and is not intended to limit the present invention. In this specification, singular forms also include plural forms unless specifically stated otherwise in a phrase. The terms 'comprises' and/or 'comprising' used in the specification do not exclude the presence or addition of one or more other elements.

In describing the specific embodiments below, several specific contents are prepared to more specifically describe the invention and aid understanding. However, readers who have knowledge in this field to the extent that they can understand the present invention can recognize that it can be used without these various specific details. In some cases, it is mentioned in advance that parts that are commonly known in describing the invention and are not greatly related to the invention are not described in order to prevent confusion for no particular reason in explaining the present invention.

Hereinafter, the configuration, function, and operation method of the pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention will be described.

First, FIG. 1 is a cross-sectional view of a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention.

As shown in FIG. 1, the pneumatic artificial muscle unit 100 using elastic energy according to an embodiment of the present invention includes an inelastic sleeve 10, an elastic tube 20, a gas injection unit 30, and an exhaust valve 50. ), it can be seen that it can be configured to include a tension spring 40 and the like.

The inelastic sleeve 10 is configured to perform contraction and expansion movements in the longitudinal direction.

That is, the non-elastic sleeve 10 is configured to perform contraction and expansion movements in the longitudinal direction while limiting deformation in the radial direction. In a specific embodiment of the present invention, the non-elastic sleeve 10 may be configured in the form of an origami corrugated pipe.

The gas injection unit 30 is connected to one end of the non-elastic sleeve 10 so that gas can be injected and supplied to the inside. The gas injection unit 10 includes an inlet 31 connected to a gas injection means, a gas supply source, etc. to inject gas, and a supply unit 32 connected to supply the injected gas into the pneumatic artificial muscle unit 100, It consists of

In addition, the exhaust valve 50 is connected to the other end of the non-elastic sleeve 10 so that gas introduced into the non-elastic sleeve 10 can be exhausted in the exhaust mode. That is, it is configured to include an opening/closing member 51 to be closed so that internal gas is not exhausted in the gas injection mode and expansion mode, and to dispose the gas in the exhaust mode, compression, and contraction modes.

The tension spring 40 is provided between the gas injection unit 30 and the exhaust valve 50 within the non-elastic sleeve 10 .

In addition, the elastic tube 20 is provided in the non-elastic sleeve 10, and one end is connected to the gas injection unit 30 and the other end is connected to the exhaust valve 50.

Therefore, when gas is injected through the gas injection unit 30, it is supplied into the elastic tube 20 and expanded, and elastic energy is stored by the expansion of the elastic tube 20.

Also, by the expansion of the elastic tube 20, the expansion of the non-elastic sleeve 10 in the radial direction is restricted, and expansion and tension are limited only in the longitudinal direction, so that the tension spring 40 is stretched and elastic energy is stored.

And when the exhaust mode progresses, the exhaust valve 50 is opened and the internal gas is exhausted, and at the same time, the elastic energy of the elastic tube 20 and the elastic energy of the tension spring 40 are converted into kinetic energy, so that the non-elastic sleeve 10 is contracted and compressed in the longitudinal direction. At this time, when the exhaust valve 50 is opened, air is rapidly exhausted, and elastic energy is immediately converted into kinetic energy, realizing fast response and high contraction ratio/high contraction force.

In addition, according to the embodiment of the present invention, when the non-elastic sleeve 10 reaches the set expansion length, a trigger means for opening the opening/closing member 51 in the exhaust valve 50 may be included.

As shown in FIG. 1, the trigger means according to an embodiment of the present invention is composed of a wire 60 having one end fixed to the gas injection unit 30 and the other end fixed to the opening/closing member 51. can The wire 60 is connected in a loose form before tension and expansion of the actuator, and when the non-elastic sleeve 10 reaches a set expansion length, the wire 60 is tensioned and operated to open the opening and closing member 51. The length at which the wire 60 reaches tension corresponds to the set expansion length.

In addition, the exhaust valve 50 includes a compression spring 52 for applying a restoring force so that the opening and closing member 51 is closed when the wire 60 is not in a tension state.

Hereinafter, a method of operating a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention will be described. Figure 2 shows a flow chart of an operating method of a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention.

First, gas is injected through the gas injection unit 30 connected to one end of the inelastic sleeve 10 that undergoes contraction and expansion in the longitudinal direction (S1).

As gas is injected and supplied to the inside, the elastic tube 20 expands and elastic energy is stored by the expansion of the elastic tube 20 (S2). 3 is a cross-sectional view of a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention at the start of gas injection.

In addition, as the elastic tube 20 expands, the non-elastic sleeve 10 limits the expansion of the elastic tube 20 in the radial direction, and induces expansion in the longitudinal direction because it is folded in an origami form. As the non-elastic sleeve 10 expands in the longitudinal direction, the tension spring 40 is stretched and stores elastic energy (S3). 4 is a cross-sectional view of a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention in an expansion/tension step.

This expansion mode is continued until the inelastic sleeve 10 reaches the set tensile length (S4).

In the exhaust and compression mode, the exhaust valve 50 is opened to exhaust the gas (S5), and at the same time, the elastic energy of the elastic tube 20 and the elastic energy of the tension spring are converted into kinetic energy (S6), and the inelastic sleeve 10 ) is contracted and compressed in the longitudinal direction (S7). That is, when the exhaust valve 50 is opened, air is rapidly exhausted, and elastic energy is immediately converted into kinetic energy, realizing fast response and high contraction ratio/high contraction force. 5 is a cross-sectional view of a pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention in an exhausting step. And Figure 6 shows a cross-sectional view of the pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention in the contraction and compression stages.

At this time, in the embodiment of the present invention, when the non-elastic sleeve 10 reaches the set expansion length, the opening/closing member 51 in the exhaust valve 50 may be opened by a trigger means.

The trigger means according to an embodiment of the present invention may include a wire 60 having one end fixed to the gas injection unit 30 and the other end fixed to the opening/closing member 51 .

7A is a cross-sectional view of a closed exhaust valve according to an embodiment of the present invention. 7B is a cross-sectional view of an open exhaust valve according to an embodiment of the present invention.

As shown in FIGS. 7A and 7B , it can be seen that when the inelastic sleeve !0 reaches the set expansion length, the wire 60 is tensioned and operated to open the opening/closing member 51 . These wires 60 are connected in a loose form before tension and expansion, and when the non-elastic sleeve 10 reaches a set expansion length, the wires 60 are tensioned and operated to open the opening/closing member 51 . The length at which the wire 60 reaches tension corresponds to the set expansion length. In addition, the exhaust valve 50 includes a compression spring 52 for applying a restoring force so that the opening and closing member 51 is closed when the wire 60 is not in a tension state.

Figure 8a is a schematic diagram showing a state in which the pneumatic artificial muscle unit using elastic energy according to an embodiment of the present invention is worn on the hip side. And Figure 8b shows a schematic diagram of the pneumatic artificial muscle unit using elastic energy according to the embodiment of the present invention expanded and stretched in Figure 8a.

As shown in FIGS. 8A and 8B , when the pneumatic artificial muscle unit 100 according to the embodiment of the present invention is used as an actuator for assisting hip extension in a wearable suit, the actuator length changes in the process of lifting the thigh forward (actuator must be longer).

In addition, if the length of the wire 60 is selected to match the movement of the thigh 1, the wire 60 is pulled in the process of lifting the thigh forward, opening the exhaust valve 50 passively, so that an additional electronic valve is not required. Also, when the thigh 1 comes down and slack occurs in the wire 60, the exhaust valve 50 is closed again by the compression spring 52.

In addition, the device and method described above are not limited to the configuration and method of the above-described embodiments, but all or part of each embodiment is selectively combined so that various modifications can be made. may be configured.

1: wearer
2: Anchor
10: non-elastic sleeve
20: elastic tube
30: gas injection unit
31: inlet
32: supply unit
40: tension spring
41: spring fixing end
42: spring fixing part
50: exhaust valve
51: opening and closing member
60: wire
100: Pneumatic artificial muscle unit using elastic energy

Claims (14)

In the pneumatic artificial muscle unit,
An inelastic sleeve that contracts and expands in the longitudinal direction;
a gas injection unit connected to one end of the non-elastic sleeve to inject gas;
an exhaust valve connected to the other end of the inelastic sleeve and through which gas introduced into the inelastic sleeve is exhausted in an exhaust mode;
a tension spring provided between the gas injection part and the exhaust valve in the non-elastic sleeve;
an elastic tube having one end connected to the gas injection unit and the other end connected to the exhaust valve in the inelastic sleeve;
a trigger means for opening an opening/closing member within the exhaust valve when the inelastic sleeve reaches a set expansion length; and
The trigger means includes a wire having one end fixed to the gas injection unit and the other end fixed to the opening and closing member,
When gas is injected through the gas injection unit, it is supplied into the elastic tube and expanded, elastic energy is stored by expansion of the elastic tube, and elastic energy is stored in the tension spring by expanding the inelastic sleeve in the longitudinal direction,
The pneumatic artificial muscle unit using elastic energy, characterized in that when the non-elastic sleeve reaches the set expansion length, the wire is tensioned and operated to open the opening and closing member.
delete delete According to claim 1,
A pneumatic artificial muscle unit using elastic energy, characterized in that for implementing variable stiffness and high contractile force through a plurality of stepwise / parallel arrangements of the elastic tube and the tension spring.
delete delete According to claim 1,
The pneumatic artificial muscle unit using elastic energy, characterized in that the exhaust valve further comprises a compression spring for applying a restoring force to close the opening and closing member when the wire is not in a tension state.
According to claim 1,
The inelastic sleeve is a pneumatic artificial muscle unit using elastic energy, characterized in that the deformation in the radial direction is limited, and configured to contract and expand in the longitudinal direction.
According to claim 8,
The inelastic sleeve is a pneumatic artificial muscle unit using elastic energy, characterized in that configured in the form of a corrugated pipe.
In the operating method of the pneumatic artificial muscle unit according to claim 1,
A first step of injecting gas through a gas injection unit connected to one end of an inelastic sleeve that undergoes contraction and expansion in the longitudinal direction;
a second step of supplying and expanding gas into the elastic tube in the non-elastic sleeve, and storing elastic energy by the expansion of the elastic tube; and
A method of operating a pneumatic artificial muscle unit using elastic energy, characterized in that it comprises a; third step of expanding the inelastic sleeve in the longitudinal direction and storing elastic energy in the tension spring.
According to claim 10,
The method of operating a pneumatic artificial muscle unit using elastic energy, characterized in that the expansion of the inelastic sleeve is limited in the radial direction and expanded in the longitudinal direction by the expansion of the elastic tube.
According to claim 11,
and a fourth step of contracting and compressing the inelastic sleeve in the longitudinal direction by opening the exhaust valve to exhaust gas and converting the elastic energy of the elastic tube and the elastic energy of the tension spring into kinetic energy. A method of operating a pneumatic artificial muscle unit using elastic energy to
According to claim 12,
In the fourth step,
A method of operating a pneumatic artificial muscle unit using elastic energy, characterized in that the opening and closing member in the exhaust valve is opened by a trigger means when the inelastic sleeve reaches the set expansion length.
According to claim 13,
The trigger means includes a wire having one end fixed to the gas injection unit and the other end fixed to the opening/closing member,
The method of operating a pneumatic artificial muscle unit using elastic energy, characterized in that when the non-elastic sleeve reaches the set expansion length, the wire is tensioned and operated to open the opening and closing member.

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