JP2000002176A - Microactuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microactuator which can be embodied in a micro- structure, can generate a smooth motion of high degree of freedom despite its simple construction, and has excellent property against failure. SOLUTION: This microactuator is equipped with a motion actuation part 1 which produces control information for specifying the form of the motion and a motion acting part 2 which has a motion element fixation part 20 where a row 21 of motion elements consisting of a plurality of motion elements is fixed and which moves according to the control information of the motion actuation part 1 in the way, wherein the motion element fixation part 20 is moved by the driven specified motion element belonging to the motion element row 21 in conformity to the control information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microactuator used for a macro machine, and more particularly to a technique for forming a microactuator motion mechanism.

[0002]

2. Description of the Related Art Conventionally, many microactuators (hereinafter simply referred to as "actuators") used in micromachines are manufactured using LSI semiconductor technology. FIG. 21 shows an example of such a conventional actuator. This actuator has a central processing unit 5
0, a plurality of motion elements 21 arranged on a substrate 53, a plurality of motion element control processors 51 provided corresponding to each of the plurality of motion elements 21, the central processing processor 50 and a plurality of motion element control processors The control information transmission connection 52 connects the control information transmission line 51 to the control information transmission line 51.

The central processing processor 50 controls the movement of the entire actuator by sending predetermined control information to each of the plurality of motion element control processors 51. That is, each motion element control processor that has received the control information generates element control information for defining the motion of each motion element and supplies it to each motion element. Each movement element makes a movement according to the received element control information. Thereby, the plurality of motion elements perform a predetermined motion as a whole, and the function as an actuator is achieved. in this way,
One processor communicates information to multiple processors,
A system in which a plurality of processors each control one motion element to control the movement of the entire actuator is called a centralized control system.

[0004]

In the conventional actuator employing the above-described centralized control system, a motion element control processor is provided for each motion element. When configured, the motion element control processor occupies a considerable amount of space, and the obstacle of miniaturization (this is called "spatial obstacle")
). Also, in the centralized control method of transmitting control information from the central processing processor to each motion element control processor, a connection for transmitting control information is required,
This connection is also a spatial obstacle.

Further, in the actuator employing the above-mentioned centralized control method, if at least one motion element control processor for operating the motion element fails, the entire actuator does not function. Therefore, there is a problem that the fault tolerance is poor.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has as its object to achieve smooth movement with a high degree of freedom despite its miniaturization and simple structure. And to provide a microactuator having excellent fault tolerance.

[0007]

In order to achieve the above object, a microactuator according to the present invention has a motion starting unit for generating control information for defining a form of motion,
A motion element fixing section to which a motion element row including a plurality of motion elements is fixed, wherein a predetermined motion element of the motion element row is driven in accordance with control information from the motion activation section; And a movement action section that moves in a form according to the control information.

The motion acting portion of the microactuator is configured such that the first motion element of the motion element row moves according to the control information from the motion activation section, and the motion is sequentially propagated to the subsequent motion elements. The motion element fixing portion is displaced, and thereby can be configured to move in a motion pattern according to the control information. In this case, the propagation of the motion in the motion element array of the motion action section can be performed such that the motion of each motion element affects an adjacent motion element.

Further, the microactuator can be configured to code the control information of the movement element in the movement between the movement elements included in the movement action section. Further, the function of the motion element action section may be determined by the arrangement of the plurality of motion elements constituting the motion action section and the control characteristics of the motion of each motion element. Furthermore, the exercise action section has a plurality of exercise element fixing sections, and the exercise start section is configured to exercise control information to each exercise element fixing section to exercise in a form corresponding to the control information. it can.

According to the present invention, since the movement information of the movement element itself is coded in the movement itself of the movement element, it is not necessary to provide a movement element control processor for each movement element as in the conventional actuator, and the central element is not required. There is no need for a connection for transmitting control information from the processing processor to the motion element control processor. Therefore, there is a space margin, so that the micromachine can be miniaturized.

Further, in the conventional centralized control system, the failure of one motion element control processor makes the entire actuator inoperative. On the other hand, according to the present invention, since the control information is coded in the motion of the motion element itself, if the influence of the motion is transmitted to the motion element in the vicinity of the failed motion element, the motion is moved to the nearby motion element. Is transmitted, there is an advantage that even if one moving element fails, the function of the entire actuator can be maintained.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an actuator according to an embodiment of the present invention will be described in detail with reference to the drawings. This actuator is called a motion element distribution type actuator, and the motion of the entire actuator is determined by the motion of minute motion elements arranged on the entire actuator.

FIG. 1 is a diagram showing the most basic configuration of an actuator according to an embodiment of the present invention. This actuator comprises a motion starting unit 1 and a motion acting unit 2. The movement activating unit 1 has a function of causing the base of the actuator to move. In addition, the motion acting part 2
Is a part that moves in accordance with control information from the movement activating unit 1. The movement of the movement acting unit 2 forms the movement of the entire actuator.

As shown in FIG. 2, the exercise activating unit 1 is composed of a processor 10, a basic exercise element 11, and a part of an exercise element fixing unit 20. The basic motion element 11 is fixed to a part of the motion element fixing part 20. The movement element fixing section 20 to which the basic movement element 11 is fixed is extended to the movement action section 2. The processing processor 10 generates control information that defines the form of movement of the movement action section 2 and supplies the control information to the basic movement element 11. The basic motion element 11 is displaced by being driven according to the control information. As the driving principle, for example, electrostatic attraction, piezo element, phase transformation of shape memory alloy, thermal expansion, and the like can be used.

As shown in FIG. 2, the motion acting section 2 includes a motion element fixing section 20 and a plurality of motion elements aligned and fixed on the motion element fixing section 20 (this is referred to as a “motion element row”). ) 21. Processing processor 10
The motion of the basic motion element 11 caused by being driven by the
(Hereinafter referred to as “upstream side”).

The motion transmitted to the most upstream motion element of the motion element row 21 is transmitted to the next motion element on the far side (hereinafter, referred to as “downstream side”) from the motion starting unit 1. Similarly, the motion of the motion element is sequentially transmitted to the motion element on the downstream side. That is, the motion element row 21 arranged in the motion element fixing unit 20 forms a transmission mechanism that transmits a motion by the motion of one motion element affecting an adjacent motion element on the downstream side.

This transmission mechanism can be realized, for example, by filling a viscous liquid between the motion elements. According to this configuration, the motion of a certain motion element is transmitted as a mechanical stimulus to the adjacent motion element on the downstream side using the liquid as a medium, and the motion of the adjacent motion element is activated. The movement between the movement elements is not limited to the liquid, and may be transmitted using, for example, a link directly connecting the movement elements. In short, any configuration may be used as long as a mechanical stimulus can be transmitted between the motion elements.

Each of the motion elements of the motion action section 2 has a function of determining its own motion form under the influence of an adjacent motion element on the upstream side. The function of this motion element greatly affects the motion form of the entire actuator. The function of this movement element will be described by taking an actuator capable of forming a freely bending movement like a protoanimal cilia as an example.

The actuator according to the first embodiment of the present invention is capable of two-dimensional movement. FIG. 3 is a side view of the actuator, and FIG. 4 is a top view. This actuator is composed of one motion starting unit 1 and two motion acting units 2 having the same configuration. As shown in FIGS. 3 and 4, the two motion acting portions 2 are fixed to the motion activation portion 1 such that the respective motion element rows 21 are parallel to each other.

Each of the motion elements of the motion element row 21 arranged on the motion element fixing section 20 of the motion action section 2 is switched on by the motion of the adjacent motion element on the upstream side, and the motion is switched on for a certain period of time. Act on the motion element fixing portion 20, which generates a bending force for bending the entire actuator. This forms a bending motion, for example, as indicated by the arrow in FIG.

In addition to turning on / off the switch of the moving element, it is also possible to code the control information of the moving element in the information of the movement of the moving element. For example, if a mechanism for determining the speed / acceleration of motion activation of the motion element according to the motion, displacement speed, and acceleration information of the adjacent motion element on the upstream side is provided, the motion activation of the motion element in the motion element fixing unit 20 is performed. Activity propagation can also be controlled.

Further, the motion acting section 2 needs a mechanism for restoring the deformation of the actuator shape caused by the movement of the actuator. For this purpose, an elastic body such as rubber can be used as a material of the actuator. According to this configuration, when the motion element stops generating force,
The actuator shape is restored by the elastic force of the elastic body. Further, not only the shape of the actuator can be restored but also a continuous repetitive motion can be performed.

Next, in the information transmission mechanism between the motion elements, how each motion element moves via a fluid will be described. FIG. 5 shows the motion of the motion element constituting the motion action section 2. As shown in FIG. 5, the position of the head of the moving element is determined by the balance of three forces such as an element generating force, an element interaction force, and an internal viscous force. This balance is expressed by the following equation (1). Here, it is assumed that there are 100 motion elements.

[0024]

(Equation 1) Here, x is the position of the head of the motion element, C is the viscosity coefficient,
E is the elastic modulus, and F (x) is the element generating force of the motion element. The left side of the equation (1) represents the internal viscous force, the first term on the right side represents the element generating force, and the second term represents the element interaction force.

Here, the internal viscous force is a force generated by the movement of the head. The element generating force is a force generated by the moving element itself according to the position of the head, and has the characteristics shown in FIG. The element interaction force is a force acting between the elements related to the elasticity of the entire actuator, and is obtained by the following equation (2) when the position of the head of the moving element is defined as shown in FIG.

(Equation 2)

FIGS. 8A to 8G show the results of simulating the active propagation of the moving element according to the above equations (1) and (2). In each of the drawings, the vertical axis indicates the position of the motion element, and the horizontal axis indicates the position of the motion action section 2 of the motion element on the motion element fixing section 20. FIG. 8A shows the initial state, and FIG. 8B to FIG.
The state changes to a propagation state as shown in FIG. As shown in FIG. 8, when the motion action section 2 is activated from the motion activation section 1, the position change and the active propagation of the head of each motion element on the motion element fixing section 20 of the motion action section 2 are realized. It can be seen that it functions as an information transmission mechanism.

Next, an actuator according to a second embodiment of the present invention will be described. As shown in FIG. 9, this actuator is composed of one motion starting unit 1 and nine motion acting units 2. Although FIG. 9 shows only a part of the motion action section 2, 100 motion elements are arranged in each motion element fixing section 20 of the motion action section 2 in this actuator. And FIG.
As shown schematically in FIG. 3 (A), only the motion acting portion 2 is taken out, the distal ends of the motion element fixing portions 20 are connected. In addition, the movement activating unit 1 includes nine movement element fixing units 20.
Generates a movement that triggers the movement of each of the.

Each of the motion elements of the motion action section 2 has a function of determining its own motion in accordance with the motion of the upstream motion element, and acts on the adjacent motion element fixing section 20 to form motion as a whole actuator. It has the function of forming an active action.

As a mechanism for determining its own movement according to the movement of the upstream moving element, the activation time of the moving element and the speed at which the activity of the moving element propagates to the downstream moving element are determined by the upstream moving element. It is assumed that it is changed (controlled) according to the displacement.

As shown in FIG. 10, the activation propagation time of each exercise element fixing section 20 (timing of the exercise in the exercise start section 1), the activation propagation speed and the activation duration time are shown in FIG. Are represented using a spatio-temporal function defined by three parameters such as In the following, for simplicity, the activity propagation rate and the activity duration are:
It is assumed that a common value is used in each exercise element fixing unit 20 and only the activation start time changes. This activation time is
It is defined by a time interval from a certain reference time.

FIG. 1 to No. 9 represents each space-time function of nine motion element fixing units 20, such as nine. When the spatiotemporal function of each motion element fixing unit 20 is cut by a time plane surrounded by a rectangle in FIG. 11A, the state of the activity of the motion element at a certain time is obtained as shown in FIG. Can be represented. A bending force is generated according to the activity of each motion element.

The bending force is generated as follows. That is, as shown in FIG. 12, on the motion element fixing portion between the two motion element fixing portions 20 with the base fixed,
In the portion where the activated motion element is located, the motion element acts on the adjacent motion element fixing portion 20 to cause kinking. This partial kinking is reflected as bending of the entire motion acting portion 20 to generate a bending force. Then, the shape of the entire actuator is determined according to the bending force.

The bending force generated according to the activity of each motion element can be obtained as follows. That is, the motion acting section 2 configured as shown in FIG. 13A is divided into 100 segments each having 9 motion elements. One segment can be considered to have a configuration as shown in FIG. Each segment generates a bending force as indicated by a vector in FIG. 13C according to the activity of the motion element. Therefore, the bending forces of all the segments can be represented as shown in FIG.
When the vectors of the respective segments are combined, the bending force generated at each portion of the motion acting portion 2 is obtained, and the shape of the motion acting portion 2 changes according to the bending force. For example, when the shape of the motion acting portion 2 is in the state shown in FIG.
When a bending force as shown in FIG. 14A is generated, the shape changes to a state shown in FIG.

The actuator according to the second embodiment configured as described above operates in two operation modes such as A mode and B mode. FIG. 15 shows specific values of three parameters (activation start time, activation propagation speed, and activation duration) in the A mode and specific values of the three parameters in the B mode. The active propagation speed is 0.55 (L / ms) in A mode and 1.25 (L / ms) in B mode. The active duration is
The time is 5.0 (ms) in the case of the A mode, and 7.0 (ms) in the case of the B mode.

The circle shown in the column of the activation start time in FIG. 15 represents a movement cycle, and one movement cycle is completed by making a round in the clockwise direction. Exercise cycle is 40m in A mode
In the case of the s and B modes, the time is 25 ms. The number written on the circumference means that the movement of the motion element fixing unit 20 corresponding to the number is started at the timing (angle) at which the number is written.

FIG. 16A shows the form of movement when the actuator operates in the A mode, that is, the state of continuous shape change of the actuator. FIG. 16B
Represents a motion mode when the actuator operates in the B mode.

This actuator is operable in an operation mode corresponding to the type of control information supplied from the motion activating unit 1 to the motion acting unit 2, so that two types of motion of the actuator can be generated. This movement form is similar to the movement trajectory of the cilia used by the protozoa for movement, and can be used as a power source for moving a minute object.

FIG. 17 shows a minute moving body using this actuator. This minute moving body is configured by adding one actuator as a power source to a main body, and is propelled by the ciliary motion of the actuator. This minute moving body can be used, for example, as a capsule that moves to an arbitrary place in a living body.

Further, as shown in FIG. 18, a small moving body can be formed by adding three actuators to the main body. 18 (A) is a perspective view of the micro movable body, FIG. 18 (B) is a top view, FIG. 18 (C) is a side view, FIG. 18 (D) is a rear view, and FIG. 18 (E) is a front view. is there. As shown in the figure, each actuator has an actuator A attached at the lower right of the main body, an actuator B at the center and an actuator C at the lower left.

As shown in FIG. 19, this minute moving body
By operating the actuator A at high speed in the B mode and operating the actuator C at low speed in the A mode,
The minute moving body can be propelled to the left. vice versa,
Actuator A in B mode and actuator C in A mode
When each of them is operated in the mode, the minute moving body can be moved rightward.

As shown in FIG. 20, when the actuator B is moved in the A mode and the actuators A and C are moved in the B mode, the minute moving body can be moved upward. A
When C and C are operated in the A mode, they can be moved downward. Further, by appropriately combining the motion modes of the three actuators, movement in an arbitrary direction becomes possible.

[0042]

As described in detail above, according to the present invention,
Despite its simple configuration, it is possible to provide a microactuator that can achieve smooth movement with a high degree of freedom and that is excellent in fault tolerance.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of an actuator according to an embodiment of the present invention.

FIG. 2 is a diagram showing a detailed configuration of an actuator shown in FIG.

FIG. 3 is a side view showing the configuration of the actuator according to the first embodiment of the present invention.

FIG. 4 is a top view showing a configuration of the actuator according to the first embodiment of the present invention.

FIG. 5 is a diagram for explaining a transmission mechanism between motion elements of the actuator according to the embodiment of the present invention.

FIG. 6 is a diagram showing characteristics of the element generating force shown in FIG. 5;

FIG. 7 is a diagram for explaining the interaction force between the elements shown in FIG. 5;

FIG. 8 is a diagram showing a simulation result of active propagation of a motion element of the actuator according to the embodiment of the present invention.

FIG. 9 is a perspective view showing a configuration of an actuator according to a second embodiment of the present invention.

FIG. 10 is a diagram for explaining a spatio-temporal function that defines active propagation of a motion element in the actuator according to the embodiment of the present invention.

FIG. 11 is a diagram for explaining active propagation of a motion element of an actuator according to a second embodiment of the present invention.

FIG. 12 is a diagram for explaining a bending force of an actuator according to a second embodiment of the present invention.

FIG. 13 is a diagram for explaining a process of obtaining a bending force of an actuator according to a second embodiment of the present invention.

FIG. 14 is a diagram illustrating a relationship between a bending force of an actuator and an actuator shape according to a second embodiment of the present invention.

FIG. 15 is a diagram illustrating an example of parameter values in each operation mode of the actuator according to the second embodiment of the present invention.

FIG. 16 is a diagram illustrating an example of a motion mode in each operation mode of the actuator according to the second embodiment of the present invention.

FIG. 17 is a diagram showing a first example in which the actuator according to the second embodiment of the present invention is used for a minute moving body.

FIG. 18 is a diagram showing a second example in which the actuator according to the second embodiment of the present invention is used for a minute moving body.

FIG. 19 is a view for explaining the left and right movement of the minute moving body shown in FIG. 18;

20 is a view for explaining the vertical movement of the minute moving body shown in FIG. 18;

FIG. 21 is a diagram showing a configuration of a conventional actuator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Exercise starting part 2 Exercise action part 10 Processor 11 Basic exercising element 20 Exercise element fixing part 21 Plural exercising elements (executing element array)

Claims (6)

[Claims] An exercise starter for generating control information for defining a form of exercise, and a movement element fixing section to which a movement element array including a plurality of movement elements is fixed, wherein A motion action section that moves when the predetermined motion element of the motion element row is driven in accordance with the control information, thereby moving the motion element fixing section, and thereby moves in a form corresponding to the control information. 2. The motion element according to claim 1, wherein the first motion element in the motion element row moves according to control information from the motion activation section, and the motion is sequentially propagated to a subsequent motion element. The microactuator according to claim 1, wherein the fixed portion is displaced, and thereby moves in a motion pattern according to the control information. 3. The microactuator according to claim 2, wherein the propagation of the motion in the motion element array of the motion action section is performed by the motion of each motion element affecting an adjacent motion element. 4. The micro-actuator according to claim 1, wherein control information of the motion element is encoded in a motion between motion elements included in the motion action section. 5. The function of the motion element action section is determined by the arrangement of the plurality of motion elements constituting the motion action section and the control characteristics of the motion of each motion element. 2. The microactuator according to claim 1. 6. The exercise action section has a plurality of exercise element fixing sections, and the exercise start section exercises control information to each exercise element fixing section to exercise in a form corresponding to the control information. The microactuator according to claim 1.