JP2017034954A - Soft actuator comprising composite material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a soft actuator which can be used as a drive device of various kinds of machines and devices, especially robot related equipment.SOLUTION: Both end portions of a cover code of a basic material are used as a coupling part, an intermediate portion is used as an operation part and an inside cavity of the operation part is filled with operation elements whose volume is expanded or reduced, or shape changes in response to electric field or magnetic field stimulus. A soft actuator includes means for converting deformation force in an axial direction of the operation elements into the deformation force in an axial direction of the operation elements by the cover code, by giving electric field or magnetic field stimulus.SELECTED DRAWING: Figure 1

Description

Detailed Description of the Invention

  The present invention relates to a soft actuator that converts electrical energy into deformation energy.

  Conventionally, electromagnetic motors and McKibben actuators (for example, Patent Document 1 and Non-Patent Document 1 below) have been used as actuators for various machines and devices, particularly robots, but these traditional hard actuators. There are various problems. For example, in the case of an electromagnetic motor, a speed change mechanism is required, so the structure is complicated, and there are problems of weight, vibration, and noise. In the case of McKibben type actuators, a large-scale device such as a compressor, supply / distribution hose, supply / distribution valve, and electrical system for controlling the valve is indispensable to press-fit a fluid such as air into the tube. Since a dual fluid system is necessary, there are problems in that the structure is complicated, the weight is difficult to carry, and the fine operation is difficult to control. On the other hand, for many years, as actuators for nursing care equipment, rehabilitation equipment, amusement equipment, etc., there has been a demand for non-rigidity, simple structure, light weight, noise-free operation, delicate operation, etc. there were.

  In order to solve the problems of actuators such as the above-mentioned electromagnetic motors and McKibben type, research and development of soft actuators (also called artificial muscles) using electrostatic force, ionic force, electromagnetic force, etc. has been conducted for many years. Soft actuator based on polymer (Electric-Active Polymer, EAP), conductive polymer thin film (Ionic conductive polymer film, ICPF), Electromagnetic software using material in which powder magnetic substance is mixed with elastomeric material Actuators have been proposed.

  For example, an ion exchange resin type actuator shown in the following Patent Document 2 includes an ion exchange resin membrane and electrodes bonded to both surfaces of the ion exchange resin membrane, and applies a potential difference to the ion exchange resin membrane in a water-containing state of the ion exchange resin membrane. This is a soft actuator that generates bending and deformation forces on the ion exchange resin film.

  Further, for example, the electromagnetic actuator shown in Patent Document 3 below is a soft actuator that embeds a coil in an elastomer material blended with magnetic powder and generates a deformation force on the elastomer material depending on the direction of current to be applied and the configuration of the coil. is there.

  Further, for example, the conductive polymer actuator shown in Patent Document 4 below is a laminate having two resin layers in a laminate having a bimorph structure, and the first resin layer is a resin having a conductive resin as a base resin. A resin layer that can be expanded and contracted by taking in and releasing anions, and the second resin layer is a resin layer having a conductive resin as a base resin, and depending on the polarity of applied voltage, It is a soft actuator that generates deformation force of expansion or contraction as a whole laminate by taking in and releasing.

JP2007-40365 Japanese Patent Laid-Open No. 4-275078 PCT / JP2008 / 072249 JP 2009-107342 A

Panasonic Technical Journal Vol. 56 No. 3 Oct. 2010 "Robot Feature: Development of Multi-DOF / Pneumatic Artificial Muscle Robot Arm Safe for Humans"

  As shown in the above-mentioned patent documents and non-patent documents, a soft actuator made of a single deformable material, that is, a soft actuator having the same function for both the operation function and the connection function, is at least two other parts that operate. Since more connection points are required and the tensile burst force due to the operation is directly received, the obtained operation force cannot in principle exceed the tensile burst strength and connection strength of the material itself, in other words, the operation and connection. If the two functions are carried out by the same material, if the strength of the operating force exceeds the tensile burst strength and connection strength of the material itself, the material itself will tear, and the strength of the resulting operating output is naturally limited. There is a problem.

  Therefore, the present invention aims to provide a soft actuator that uses a composite material and solves the above-described problems, has a simple structure, is lightweight, noise-free, convenient for carrying, and can be firmly connected. .

  As is known, an ideal soft actuator is a living muscle. In general, the movement of a human body is performed by contraction of a pair of skeletal muscles (also called voluntary muscles or antagonistic muscles, but striated muscles in histology) straddling a joint. Skeletal muscle consists of two parts, tendon and muscle. Both ends of the muscle abdomen (muscle assembly) are tendon parts, one of which is connected to the bone as a mediator, and the other is a number of myofibrils at the cellular level. And is responsible for the link function. The muscle abdominal part composed of a number of myofibrils contracts by about 20% by the operation signal from the brain, and assumes the operation function. That is, the characteristics of skeletal muscles share different roles so that the muscles do not have a function of connecting and the tendon portion does not have a function of actuating (contracting). The advantage of such a mechanism that separates the connecting function and the operating function is that the structure is simple, and the maximum output, toughness, and durability can be achieved by making the best use of both the connection strength and the muscle contraction force (operating force). It is believed that it can be obtained and can operate quickly and accurately, and energy can be used efficiently.

  Under the above problems, the present inventor obtains a hint from the mechanism of biological muscles, uses the cover cord as a base material, uses both end portions as connecting portions, and intermediate portions as operating portions. An element whose volume expands or contracts or changes its shape in response to an electric or magnetic stimulus, for example, a soft actuator made of a single material (hereinafter referred to as an “actuating element”) is filled in the working part cavity. . Provided is a soft actuator characterized by having means for applying an electric or magnetic stimulus to the actuating element and converting a radial deformation force of the actuating element into an axial deformation force of the actuating portion by a cover cord. To do.

  Furthermore, the present invention provides means for adjusting the width of the operation stroke and the strength of the operation output by connecting a large number of the above basic units in series in the axial direction or in parallel, or by connecting in series and parallel at the same time. And an assembly of soft actuators made of a composite material.

  Furthermore, the present invention includes means for adjusting the pattern of the operation output by adjusting the physical property, configuration, size of the operation element, or the pattern of electric or magnetic stimulation applied to the operation element. A soft actuator made of a composite material or a collection of soft actuators made of a composite material.

  According to the present invention, it is possible to provide a soft actuator that is simple in structure, lightweight, noise-free, convenient for carrying, and can be firmly connected.

It is a figure for demonstrating one Embodiment of this invention. It is a figure for demonstrating Example 1 of this invention. It is a figure for demonstrating Example 2 of this invention. It is a figure for demonstrating Example 3 of this invention.

Embodiment

  The present invention will be described below with reference to the drawings. FIG. 1 is a diagram for explaining a basic unit 20 of an embodiment of a soft actuator made of a composite material of the present invention. FIG. 1 (a) is a side view of the basic unit 20, and in FIG. Is based on a cylindrical shape (also called a circular knitted tube or cylindrical knitted sleeve) that is circularly knitted with nylon fiber, which has little elasticity, and its features are binding force only in the axial direction. The expansion force can be converted into an axial contraction force. Conversely, the axial extension force can be changed to a reduction force in the radial direction of the cavity. That is, the change in the length of the cover cord 1 is inversely proportional to the change in the intracavity radial direction. FIG. 1A shows an intermediate state when no power is supplied.

  In this embodiment, both ends of the cover cord 1 are bundled in a rope shape, hardened with a resin to form a connecting portion 2, and an intermediate portion is used as an operating portion 3. A molecular material cell 4 (hereinafter referred to as cell 4) is filled. The characteristics of the laminated conductive polymer material cell 4 are such that the volume expands in the radial direction when a positive voltage is applied (the display of an electric circuit or the like is omitted, the same applies hereinafter), and the volume when a negative voltage is applied. Shrinks in the radial direction. In this embodiment, the proportionality between the length of the actuating part 3 and the volume of the cell 4 is that when a positive voltage is applied to the cell 4, the radial expansion deformation causes the actuating part 3 to shorten about 20% at maximum, When a negative voltage is applied, a setting is made so that the contraction deformation in the radial direction can extend up to about 20% in the operating portion 3. The electric conducting wire 5 for the cell 4 is a flexible conducting wire on the outer periphery of the operating unit 3 and is woven so that it can be bent or stretched in accordance with the change in the outer peripheral dimension of the operating unit 3. The upper end 201 of the connecting portion 2 is fixed to the fixed object 6, the lower end 202 is used as the output end, and the weight 16 is connected. As shown in the present embodiment, the connecting portion 2 and the operating portion 3 share the roles of the connecting function and the operating function, respectively, so that the cover cord 1 can use a tough fiber material having no elasticity, and in various ways. The connection strength is independent of the strength of the working material and the strength of the output. The working material cell 4 is independent of the connecting function.

  If a positive voltage drive signal is applied to the cell 4 (the display of the electric circuit is omitted), the working material cell 4 in the cavity of the working part 3 expands in the radial direction. The structure is converted into the contraction force in the axial direction of the operating portion 3, and the operating portion 3 is shortened. As a result, as shown in FIG. 1B, a corresponding contraction force and operating stroke can be obtained at the output end 202, and the weight 16 moves upward. When the positive drive signal is stopped, the cell 4 returns to the original length, and the weight 16 returns to the intermediate position. On the contrary, if a negative voltage is applied to the cell 4, the working material cell 4 in the cavity of the working unit 3 is contracted in the radial direction. The gravity of the weight 16 and the structure of the cover cord 1 cause the working material 3 to move in the axial direction. It is converted into an extension force, and the operating part 3 becomes longer. As a result, the weight 16 moves downward as shown in FIG. When the negative drive signal is stopped, the cell 4 returns to the original length, and the weight 16 returns to the intermediate position.

  FIG. 2 is a diagram for explaining Example 1 according to the embodiment of the present invention, and uses the basic unit 20 of the above embodiment, and constitutes a robot arm 30 that simulates a human upper limb as an artificial muscle. FIG. 2A shows an unenergized state, and parts 10, 11, 11, 12 and 13 in the figure are regarded as humerus, forearm, biceps and triceps, respectively. Parts 10 and 11 are connected by a joint 14. The part 12 functions as an operating device of an assembly in which five of the basic units 20 are connected in series, and connects an electrical conductor to the electrical circuit 50 (details of the electrical circuit 50 are omitted, the same applies hereinafter). One end of the part 12 is fixed to the upper end of the part 10, and the other end is fixed to the part 11. Similarly, the part 13 also functions as a single actuating device of an assembly of five basic units 20 connected in series, and is mounted on the opposite side of the part 12 across the part 10 as shown in FIG. One end thereof is fixed to the other side of the upper end of the part 10, and the other end is fixed to the part 11.

  If the robot arm 30 is installed in a horizontal position (parts 10 and 11 are on the same horizontal plane) and a positive voltage drive signal is applied to the part 12, the entire part 12 contracts, and at the same time a negative voltage is applied to the part 13, The entire part 13 was extended, and therefore the part 11 moved in the direction of refraction as shown in FIG. On the contrary, if a negative voltage drive signal is applied to the part 12, the entire part 12 expands, and if a positive voltage is applied to the part 13 at the same time, the entire part 13 contracts, as shown in FIG. 11 moved in the direction of extension.

  If the polarity, voltage, frequency, timing, and the like of the drive signal output from the electric circuit 50 are changed based on the basic operating principle described above, the robot arm 30 can perform various operations.

  FIG. 3 is a diagram for explaining Example 2 according to the above-described embodiment. In Example 2, the above-described basic unit 20 is used, and a “cuff” (also referred to as a compression bag) for a pneumatic band massager is used. Configure The same parts as those in the first embodiment are denoted by the same reference numerals, and redundant description is omitted. A “cuff” is a band, generally used in a ring shape. The cuff actuating means for the conventional pneumatic band massager, that is, the means for changing the inner diameter of the cuff is electric energy, and the air compressor (air pump) is turned and air is injected into the cuff by an air supply / exhaust mechanism. Or discharge and inflate or deflate the cuff. Such a conventional cuff is called a “pneumatic cuff”.

  As can be seen from the operation means of the conventional “pneumatic cuff”, an air compressor and an air supply mechanism are indispensable to operate, so the weight of the air compressor and motor, the air supply mechanism itself is large, Since an air supply hose and an air supply control valve are required, the overall structure of the device is large and complicated, and there are problems such as noise and vibration during operation, and inconvenience in carrying.

  FIG. 3 (a) is a diagram showing the structure of the band-type massager cuff 7, in which the main body of the cuff 7 is sewn with a strong fabric, and the above-mentioned is along the longitudinal direction in the above. Aggregates 21, 22, and 23 in which five of the basic units 20 are connected in series are provided in parallel, placed in the cuff 7, and both ends are sewn to the cuff 7. Wiring is arranged for each column and connected to the electric circuit 50 so as to be driven separately. The connecting magic tape 15 is sewn to both ends of the cuff 7.

  FIG.3 (b) is a figure which shows the state which winds the cuff 7 around a thigh part and operates. If a positive voltage drive signal is applied simultaneously from the electric circuit 50 to the aggregates 21, 22, 23, the aggregates 21, 22, 23 contract simultaneously to compress the calves and if the drive signal stops, the aggregates 21, 22 , 23 return to their original length, and this expansion / contraction action provides a massage effect. Alternatively, if a positive voltage drive signal is applied from the electric circuit 50 to the aggregates 21, 22, 23 in order or in reverse order, or at regular intervals, the aggregates 21, 22, 23 contract separately. Various massage effects can be obtained by pressing the calves. The band-type massager using the cuff 7 of this embodiment does not require an air pump, an air supply hose, etc., is lightweight, noise-free, and convenient to carry, so it can be used in various environments, especially economy class syndrome Appropriate for prevention. And it can be applied not only to the thighs but also to other parts such as the upper arm.

  FIG. 4 is a diagram for explaining the cuff 8 for an electronic blood pressure monitor of Example 3 according to the above-described embodiment, and the main body of the cuff 8 in FIG. 4A is sewn with a strong cloth. An assembly 24 in which five of the basic units 20 are connected in series is provided in the longitudinal direction in the longitudinal direction, and the assembly 24 is placed in the cuff 8 and both ends are sewn to the cuff 8. The electrical conductors of the assembly 24 are connected to the electrical circuit 50. In addition, a sensor 9 for detecting the movement of blood flow is provided in the cuff 8, and the electric conductor is connected to the electric circuit 50. The connecting magic tape 15 is sewn to both ends of the cuff 8.

  FIG. 4B is a diagram showing a state in which the cuff 8 is wound around the upper arm and used. When a positive voltage drive signal is applied to the assembly 24 from the electric circuit 50, the assembly 24 contracts and compresses the blood vessels of the upper arm. Simultaneously, detection of the sensor 9 and processing of the electric circuit 50 cause the systolic and diastolic phases. Measure and display blood pressure and pulse. The electronic sphygmomanometer using the cuff 8 of this embodiment does not require an air pump, an air supply hose, etc., is lightweight, noise-free, and convenient to carry, and can be used in various environments.

  The present invention is not limited to the above-described embodiment of the present invention, and it is needless to say that various modifications can be made without departing from the gist of the present invention. In addition, the material and configuration of the cover cord may be various fiber materials having sufficient strength, and any material that efficiently causes the intracavity radial deformation force to appear in the axial expansion / contraction force. As the material and configuration of the actuating element filled in the actuating portion cavity, any material may be used as long as the volume expands or contracts or the shape changes efficiently in response to an electric or magnetic stimulus.

The soft actuator made of the composite material of the present invention is simple in structure, light weight, noise-free operation, and convenient for carrying. Therefore, it can be applied to various fields as described below.
1) Industrial fields such as actuators for various robots, drive devices for production lines, actuators for air and underwater operations.
2) Medical and welfare fields such as power assist devices, prosthetic legs, prosthetic hand actuators, surgical and nursing support devices.
3) Information and entertainment fields such as virtual reality fitback devices, bodily amusement game machines, and training equipment.

DESCRIPTION OF SYMBOLS 1 Cover cord 2 Connecting part 3 Actuating part 4 Actuating element 5 Electrical conductor 6 Fixed object 7 Band type massager cuff 8 Electronic blood pressure cuff 9 Sensor for detecting blood flow 10 Part hitting the humerus 11 Hit the forearm bone Part 12 Part that hits the biceps 13 Part that hits the triceps 14 Joint 15 Velcro 16 for looping the cuff Weight 20 One basic unit 21, 22, 23 of the basic unit 20 of Example 2 Assembly 24 in which pieces are connected in series Assembly 30 in which five of basic units 20 of Example 3 are connected in series 30 Robot arm 50 Electric circuit 201 Upper end 202 of connecting portion 2 Lower end of connecting portion 2

Claims (4)

  An actuating element whose volume expands or contracts in response to an electric or magnetic stimulus in the working part cavity, or whose shape changes in the working part cavity, with both ends of the cover cord of the base material as the connecting part and the intermediate part as the working part. Fill. A soft actuator comprising: means for converting a radial deformation force of an operating element into an axial deformation force of an operating portion by a cover cord by applying an electric field or magnetic field stimulus.   The soft actuator according to claim 1 is a basic unit, and many of them are connected in series in the axial direction or connected in parallel, or connected in series and parallel at the same time, so that the width of the operation stroke and the strength of the operation output can be reduced. An assembly of soft actuators made of a composite material, characterized by comprising means for adjusting.   A means for adjusting a pattern of an operation output by adjusting a physical property, a configuration, a size, or a pattern of an electric field or a magnetic field applied to the operation element. 2. A soft actuator composed of two composite materials and an assembly of soft actuators composed of composite materials.   A device, an apparatus, and a product having the soft actuator made of the composite material according to claim 1, 2, and the assembly thereof.

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