WO2022246728A1

WO2022246728A1 - Method and system for optical fiber actuator to spontaneously generate periodic continuous mechanical motion

Info

Publication number: WO2022246728A1
Application number: PCT/CN2021/096310
Authority: WO
Inventors: 吕久安; 胡志明
Original assignee: 西湖大学
Priority date: 2021-05-26
Filing date: 2021-05-27
Publication date: 2022-12-01
Also published as: CN113309677B; CN113309677A

Abstract

A method and system for an optical fiber actuator to spontaneously generate periodic continuous mechanical motion. An optical fiber actuator having multiple degrees of freedom is prepared and obtained by combining a two-step crosslinking method by means of thread die forming, a load is suspended below the fiber actuator, and a light source is driven to irradiate the fiber actuator to enable the fiber actuator to generate a spontaneous and periodic continuous mechanical motion, thereby achieving a controllable universal spontaneous and periodic continuous mechanical motion system having high degree of freedom and load capacity.

Description

A method and system for spontaneously generating periodic continuous mechanical motion of an optical fiber actuator

technical field

The invention relates to the field of photomechanical conversion, in particular to a method and system for spontaneously generating periodic continuous mechanical motion of an optical control fiber actuator.

Background technique

The intelligent behavior design of animals and plants in nature and the development of advanced intelligent materials and devices provide a steady stream of inspiration. Automatic cyclical movement behaviors generally exist in important life activities of animals and plants, such as the periodic and continuous flapping of wings when birds fly, the high-speed cyclic swing of tails when tuna swims, and the periodic rhythmic beating of animals' hearts. These automatic cyclic life activities are based on non-equilibrium systems, which can generate continuous automatic cyclic motion through constant chemical energy input. However, artificial stimuli-responsive material systems are mainly balanced systems, usually with two or more equilibrium or metastable structures/states, and switching structures/states depends on switching external stimuli. Under constant external stimuli, these stimulus-responsive material systems can only generate single-shot mechanical motion behaviors, severely lacking in automatic properties.

In response to this situation, scientists and engineers have tried to assemble systems with synthetic materials that can achieve spontaneous, periodic and continuous mechanical motion behavior. There are mainly two types of materials used, one is driven by pH value or Belousov-zhabotinsky reaction smart gels, another is photosensitive liquid crystal polymers, however, smart gels must be operated under wet conditions because their driving force is caused by swelling and deswelling of stimuli-responsive gels, whereas in most Practical applications need to give priority to a dry environment, that is to say, the applicable scenarios of smart gels are limited. For photosensitive liquid crystal polymers, it is usually processed into independent strips as oscillators, which use the self-shielding effect to generate a bent/unbent feedback loop to obtain vibrations, and the main degree of freedom is bending deformation, due to its lack of multiple degrees of freedom, making it very challenging to achieve multiple motion modes in a single photosensitive liquid crystal polymer actuator, especially when it comes to the controllability of various motion modes in a single actuator, which becomes more challenging. In addition, the currently studied spontaneous, periodic and continuous mechanical motion systems cannot work under load, because the load will change and affect its equilibrium conditions to hinder its motion, while practical engineering application scenarios need to resist external loads.

Therefore, smart stimuli-responsive materials with high degrees of freedom and loading capacity are urgently needed to develop spontaneous, periodic and continuous mechanical motion systems with controllable motion patterns and external work for practical applications.

Contents of the invention

The purpose of the present invention is to provide a method and system for spontaneously generating periodic continuous mechanical motion of an optical control fiber actuator. A multi-degree-of-freedom deformation optical control fiber actuator is prepared by thread mold forming combined with a two-step cross-linking method. Spontaneous, periodic continuous mechanical motion can be generated under light control conditions to realize a controllable general spontaneous, periodic continuous mechanical motion system with high degrees of freedom and load capacity.

In order to achieve the purpose of the above invention, this technical solution provides a method for spontaneously generating periodic continuous mechanical motion of an optically controlled fiber actuator, including the following steps: suspending the load on the end of the fiber actuator, driving a light source to irradiate any part of the fiber actuator position, where the fiber actuator is prepared from a photoresponsive material doped with a light absorber, and under the stimulation of the driving light source, the linear structure undergoes bending, twisting, curling, and the contraction of the curled fiber transforms into a helical structure.

In some embodiments, changing the light intensity of the driving light source, the spot size and the irradiation position drives the fiber actuator to generate different mechanical motion modes, including at least one of tilting motion, rotating motion and up and down motion.

In some embodiments, when the driving light source irradiates the connection between the fiber actuator and the load, the fiber actuator is driven to generate continuous tilting motion, the amplitude of the tilting motion is ±0-±90°, and the frequency is 0-100 Hz.

In some embodiments, when the driving light source irradiates the part where the fiber actuator is not connected to the load, the amplitude of the rotational motion is ±0˜±1000°, and the frequency is 0˜10 Hz.

In some embodiments, when the driving light source irradiates the non-connected part of the fiber actuator and the load, the driving fiber actuator generates continuous up and down movement, the amplitude of the up and down movement is ±0~±2m, and the frequency is 0~100Hz.

In some embodiments, the irradiation position or illumination of different driving light sources is adjusted, and the fiber actuator is driven to generate a compound mechanical motion, wherein the compound mechanical motion includes a compound of tilting motion and rotating motion, and a compound of up and down motion and rotating motion.

In some embodiments, the payload is placed in various gas environments and high damping liquid environments.

In some embodiments, the load is a magnetic rod placed in the coil, and the light source is driven to drive the magnetic rod to generate an up and down movement and cut the magnetic induction line to generate current.

In some embodiments, the load is an optical mirror, and the light source is driven to drive the optical mirror to move in different modes. When the laser beam is irradiated on the optical mirror, the laser beam is steered or linear and waveform light scanning is realized.

In the second aspect, this solution provides a system in which optically controlled fiber actuators spontaneously generate periodic and continuous mechanical motions, including: fiber actuators, wherein the fiber actuators are prepared from light-responsive materials doped with light absorbers. Under the stimulation, the linear structure undergoes bending, twisting, curling and the contraction of the coiled fiber transforms into a helical structure; the load is suspended at the end of the fiber actuator; and the driving light source is used to illuminate the fiber actuator to drive the fiber actuator to spontaneously generate a cycle Continuous mechanical movement.

Compared with the prior art, this technical solution has the following characteristics and beneficial effects: it utilizes four kinds of multi-degree-of-freedom deformation behaviors generated during the transformation process between the linear structure and the helical structure of the fiber actuator: bending, torsion, curling and the like of the fiber. The contraction of the crimped fiber, using local irradiation or patterned irradiation of the fiber actuator, not only realizes the spontaneous and periodic continuous mechanical motion behavior of the three basic modes of the light-controlled fiber actuator: tilting motion, rotating motion, and up and down motion, but also realizes A variety of complex spontaneous and periodic continuous mechanical motion behaviors combining different basic modes.

In addition, this solution can also realize the free switching of fiber actuators in different modes by changing the intensity of incident light, the shape and size of the light spot, and the orientation of the light spot, and can adjust the frequency and amplitude of spontaneous and periodic continuous mechanical motion behavior; through Change the load at the lower end of the fiber actuator to realize the functional reconstruction of the self-vibration system. For example, if the load is a magnetic rod, the fiber actuator can be used to generate electricity; when the load is an optical mirror, the fiber actuator can be used for Laser light modulation.

Description of drawings

Fig. 1 is a schematic diagram of the fabrication principle of a fiber actuator according to an embodiment of the present invention.

Fig. 2 is a schematic diagram of three motion modes of the fiber actuator according to an embodiment of the present invention.

Fig. 3 shows that the optical control fiber actuator produces a spontaneous, periodic and continuous mechanical motion behavior system according to an embodiment of the present invention to produce tilting motion under light stimulation.

Fig. 4 shows that the optical control fiber actuator generates spontaneous, periodic and continuous mechanical motion behavior system according to an embodiment of the present invention to generate rotational motion under light stimulation.

Fig. 5 shows that the optical control fiber actuator generates spontaneous and periodic continuous mechanical motion behavior system according to an embodiment of the present invention to generate up and down motion under light stimulation.

Fig. 6 shows that the optical control fiber actuator produces spontaneous, periodic and continuous mechanical motion behavior system according to an embodiment of the present invention. Under light stimulation, the complex spontaneous periodic and continuous mechanical motion is generated, and the mode includes tilting motion and rotational motion.

Fig. 7 shows that the optical control fiber actuator produces spontaneous, periodic and continuous mechanical motion behavior system according to an embodiment of the present invention. Under light stimulation, the compound spontaneous periodic and continuous mechanical behavior is produced, and the mode includes up and down motion and rotational motion.

Fig. 8 shows that the optical control fiber actuator on the fluid interface generates spontaneous, periodic and continuous mechanical motion behavior system according to an embodiment of the present invention to generate rotational motion under light stimulation, and the applicable environment is a gas or gas-liquid interface.

Fig. 9 shows the spontaneous, periodic and continuous mechanical movement of the optical fiber actuator according to an embodiment of the present invention, and the tilting movement under the stimulation of concentrated sunlight.

Fig. 10 is an application of an optical control fiber actuator to generate spontaneous, periodic and continuous mechanical motion behavior system for laser guidance according to an embodiment of the present invention.

Fig. 11 is an optical control fiber actuator generating spontaneous, periodic and continuous mechanical motion behavior system for energy collection according to an embodiment of the present invention.

Fig. 12 is a schematic diagram of the effect of light intensity and spot size on the motion mode of the fiber actuator.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments of the present invention belong to the protection scope of the present invention.

Those skilled in the art should understand that in the disclosure of the present invention, the terms "vertical", "transverse", "upper", "lower", "front", "rear", "left", "right", " The orientation or positional relationship indicated by "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present invention and The above terms should not be construed as limiting the present invention because the description is simplified rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation.

It can be understood that the term "a" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element The quantity can be multiple, and the term "a" cannot be understood as a limitation on the quantity.

This scheme provides a method and system for spontaneously generating periodic continuous mechanical motion of an optically controlled fiber actuator. A fiber actuator is prepared by using a photodeformable intelligent polymer material, and a light absorber is doped in the fiber actuator. Due to the photothermal excitation effect of the complex light absorber, the light irradiation will locally increase the temperature of the fiber actuator, and the temperature change will further trigger the deformation of the fiber in the light irradiation area. In this embodiment, the light absorbing agent doped therein is graphene, which can convert near-infrared light into heat to realize the effect of light stimulation to produce deformation. Deforms under light.

This in turn triggers the following movement patterns:

Under light irradiation, the morphological change of the fiber actuator causes the irradiated fiber actuator to deform and tend to move out of the spot radiation area, and the fiber actuator that leaves the spot radiation area continues to move away from the spot after leaving the spot radiation area , this delay is attributed to the time difference Δt required for photothermomechanical transfer and the inertia acquired by the fiber during motion. When the fiber actuator leaving the spot radiation area cools down, it undergoes recovery deformation and returns to the spot radiation area. The fiber actuator returning to the light-irradiated area will repeatedly perform reversible in-and-out motions in and out of the spot-irradiated area, thereby forming an optomechanical feedback loop to generate spontaneous, continuous mechanical motion.

Through the above motion methods, it not only realizes the spontaneous and periodic continuous mechanical motion behavior of three basic modes of optical control fiber actuators: tilting motion, rotating motion, and up and down motion, but also realizes complex spontaneous, Periodic continuous mechanical motion behavior, such as compound spontaneous periodic continuous mechanical behavior combining tilt and rotational motion, and compound spontaneous periodic continuous mechanical behavior combining rotation and up-and-down motion.

And this scheme can realize the free switching of different mechanical motion modes by changing the incident light intensity, the shape and size of the incident light spot, and the position of the light spot on the fiber actuator, as well as adjust the frequency and amplitude of spontaneous and periodic continuous mechanical motion behavior. This is a brand-new light-driven method to generate continuous mechanical motion, which has considerable potential application value in the fields of micro-mechanical systems, soft robots and new energy.

Specifically, this solution provides a fiber actuator, which is prepared by using photodeformable smart polymer materials, and the preparation material is doped with a light absorber. Specifically, the preparation method of the fiber actuator is as follows:

The monomer containing mesogen and the material containing light-to-heat conversion are preliminarily polymerized and formed in a mold with a thread structure by bonding or doping through enol click reaction, Michael addition reaction or free radical polymerization, and peeled off to obtain The incompletely cross-linked helical fiber precursor; the incompletely cross-linked helical fiber precursor is stretched and untwisted to obtain a straight fiber, and the straight fiber is stretched to set a ratio to fix the shape and orientation.

Specifically, the helical fiber precursor has a weakly crosslinked network formed by a chemical crosslinking reaction. After initial curing, the molded incompletely crosslinked helical fiber precursor is taken out from the mold; it is then used as a precursor The material is straightened, untwisted and further stretched. After the tensile strain is fixed, the stress gradient on the cross-section of the straightened helical fiber precursor is induced and fixed by the chemical cross-linking reaction, and the multi-degree-of-freedom deformation is obtained. fiber actuator.

Among them, the liquid crystal elastomer oligomer is a monomer containing mesogens and a material containing light-to-heat conversion through bonding or doping through enol click reaction, Michael addition reaction and free radical polymerization. The helical fiber precursor obtained by preliminary polymerization in the mold has a weakly cross-linked network formed by chemical cross-linking reactions. When the helical fiber precursor is stretched in the axial direction, due to the different lengths of the inner and outer sides of the helical fiber precursor, the stress accumulated on the inner side is much larger than that on the outer side. After the stretching operation, it is induced by a chemical crosslinking reaction. And the stress gradient on the straightened spring fiber cross-section is fixed, and then the photodeformable fiber actuator is obtained.

In this solution, the material containing light-to-heat conversion can absorb light and convert it into heat under light irradiation, and the material containing light-to-heat conversion can be carbon nanotubes, graphene, light-absorbing dyes, light-absorbing inks, etc. And according to the different reactions of light absorbers to light, different driving light sources can be used to control the fiber actuator.

In addition, in the stretching stage, the thiol group and the olefin group are completely cross-linked and solidified to obtain a multi-degree-of-freedom fiber actuator with uniaxial orientation, which changes from a linear structure to a helical structure when illuminated, Bending, torsion, curling, and shrinkage of the spring-like actuator formed by curling during the transformation process become smaller.

Specifically, the components of the helical fiber precursor can be selected from a liquid crystal monomer containing an acrylate double bond, a crosslinking agent containing a thiol group, and a combined monomer of a light absorber, and the combined monomer is dissolved in an organic solvent to obtain Mix the solution, ultrasonically disperse the mixed solution, add a catalyst to catalyze the chemical crosslinking between the combined monomers, and place it in a screw mold for preliminary curing to form a helical fiber precursor.

In one embodiment of this scheme, a liquid crystal elastomer oligomer is obtained through enol click reaction, wherein RM82 is selected as the liquid crystal monomer containing acrylate double bond, DODT and PETMP are selected as the monomer containing thiol group, and the light absorption Graphene is selected as the agent, and the corresponding fiber actuator can respond to near-infrared light. RM82:DODT is 1.67:1, DODT:PETMP is 3:1 molar ratio, the mass ratio of graphene is 2%, organic The solvent of choice was chloroform. Of course, other combined monomers that meet this condition can also be used as the material of the helical fiber precursor.

The catalyst can also be selected (DPA di-n-propylamine, HexAM hexylamine, TEA triethylamine, N, N, N ₀ , N0-tetramethyl-1,8-naphthalene diamine (PS) and 1,8-diazo Heterobispiro[5.4.0]undec-7-ene; 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and 1 5-diazabicyclo[4.3 .0] non-5-ene (DBN), etc., select 2wt% DPA as catalyst in the present embodiment.

In the stretching stage, the straight fiber can be stretched by 10%-100% and fixed for 18-30h. , the embodiment of this program stretches the linear fiber by 50%; in addition, in an embodiment of this program, the linear fiber is stretched and then fixed for 24 hours.

The cross-sectional area of the fiber actuator obtained by this scheme is 0.001-100cm ² , and the material of the fiber actuator is a photodeformable material. Shrinkage deformation.

This solution provides a system for spontaneously generating periodic and continuous mechanical motion of optically controlled fiber actuators, including fiber actuators with high degrees of freedom of deformation, driving light sources, and loads obtained from the above introduction. The photoresponsive material is prepared, and under the stimulation of the driving light source, the linear structure undergoes bending, twisting, curling and contraction of the curled fiber into a helical structure; the load is suspended at the end of the fiber actuator to drive the light source for illuminating the fiber Actuator-driven fiber actuators spontaneously generate periodic continuous mechanical motion.

The specific principle: when the light source is driven to irradiate a specific position of the fiber actuator, part of the irradiated fiber actuator is deformed and moves away from the spot radiation area, and the fiber actuator far away from the spot radiation will continue to operate after leaving the spot radiation area. Moving away from the fiber actuator, when the temperature of the fiber actuator leaving the spot radiation area cools down, the fiber load rapidly deforms and recovers under the action of the free restoring force and the load, returns to the spot radiation area, and then reciprocates.

It is worth mentioning that the radiation area of the spot is small. When the fiber originally located in the radiation area of the spot changes from a linear structure to a three-dimensional structure away from the radiation area of the spot, the fiber deviates from the radiation area of the spot and forms a three-dimensional structure. Other fibers do not It will fall into the radiation area of the spot. In addition, the amount of material loaded at the lower end of the fiber is closely related to the size and modulus of the fiber actuator. The diameter of the fiber actuator selected in this project is about 300 microns, and the mass of the lower end load is 0-10g. It is worth noting that the size of the fiber actuator can be adjusted by the size of the mold. If the size is large enough, the mass of the lower end load is not limited.

In other words, the load is suspended at the end of the fiber actuator, and the illuminated fiber actuator forms a spot irradiation area, and the fiber actuator located in the spot irradiation area has a tendency to move away from the spot radiation area, which makes the fiber actuator linearly The structure changes into a helical structure, and then the fiber actuator is far away from the spot radiation area, and when the temperature of the fiber actuator leaving the spot radiation area cools down, it has a tendency to restore the linear structure, and it quickly returns to the spot radiation area under the action of the load, and then Carry out reciprocating mechanical movement.

The driving light source is any one of sunlight, ultraviolet light, visible light, blue light, red light and near-infrared light. The selection of the driving light source depends on the type of light absorber used to prepare the fiber actuator. If the light absorber absorbs For near-infrared light, select a near-infrared light-driven light source. For example, if the light absorber is graphene, select near-infrared light as the driving light source.

The light intensity, spot size and size of the driving light source can be adjusted, the movement rate of the fiber actuator can be adjusted by adjusting the light intensity of the driving light source, and the movement range of the fiber actuator can be adjusted by adjusting the light spot size and size of the driving light source . In addition, the driving light source is fixedly irradiated on a part of the fiber actuator to form a spot radiation area.

The load is not limited by shape, size and weight, but the weight of the load should not be greater than the deformation driving force of the fiber actuator. Moreover, the load at the lower end of the optical control fiber actuator of this solution can generate spontaneous and periodic continuous mechanical motion behavior in various gas environments and high damping liquid environments.

When the load is placed in the magnetic rod of the coil, the magnetic rod can be driven to generate an up and down movement and cut the magnetic induction line to generate current through the method of this solution.

If the load is an optical mirror, the fiber actuator drives the optical mirror to produce different modes of movement. When the laser beam is irradiated on the mirror, the laser beam can be steered or linear and waveform light scanning can be realized.

In the third aspect, this solution provides a method for spontaneously generating periodic continuous mechanical motion of an optically controlled fiber actuator. The load is suspended at the end of the fiber actuator, and the light source is driven to irradiate any position of the fiber actuator, wherein the fiber actuator is controlled by The light-responsive material doped with light-absorbing agent is prepared, and under the stimulation of the driving light source, the linear structure undergoes bending, twisting, curling and contraction of the coiled fiber to transform into a helical structure. The light absorber of the fiber actuator produces a photothermal excitation effect when stimulated by the driving light source, which increases the temperature of the fiber actuator, and the temperature change triggers the deformation of the fiber in the radiation area of the spot.

Wherein the fiber actuator is hung vertically, and the load is placed at the lower end of the fiber actuator.

When the connecting part of the fiber actuator and the load is illuminated, the fiber actuator is driven to produce continuous tilting motion; at this time, the amplitude and frequency of the tilting motion can be adjusted by controlling the intensity of the driving light source. Generally speaking, the light intensity of the driving light The greater the strength, the greater the amplitude of the tilting motion, and the lower the corresponding frequency. At this time, the controllable driving light intensity is 0.01-10W cm ^-2 , correspondingly, the amplitude of the tilting motion is ±0-±90°, and the frequency is 0-100Hz.

When the part where the fiber actuator is not connected to the load is illuminated, the fiber actuator is driven to generate continuous rotational motion; at this time, the amplitude and frequency of the rotational motion are adjusted by controlling the intensity of the light source. Generally speaking, the light that drives the light intensity The greater the strength, the greater the amplitude of the rotational motion and the lower the corresponding frequency. At this time, the controllable driving light intensity is 0.01-3W cm ^-2 , correspondingly, the amplitude of the rotational motion is ±0-±1000°, and the frequency is 01-10Hz.

When the part where the fiber actuator is not connected to the load is illuminated, the fiber actuator is driven to produce continuous up and down motion; at this time, the amplitude and frequency of the up and down motion are adjusted by controlling the intensity of the light source. Generally speaking, the light that drives the light intensity The greater the strength, the greater the amplitude of the up and down movement, and the lower the corresponding frequency. At this time, the light intensity of the driving light can be controlled to be 3-10W cm ^-2 , correspondingly, the amplitude of the up and down movement is ±0-±2m, and the frequency is 0-100Hz. For the up and down movement mode, the fiber actuator needs to produce a complete winding deformation under stimulation, similar to the effect of a spring, so as to drive it to produce up and down movement.

It should be noted that the strength of the stimulus source needed to generate the up-and-down movement pattern is a little higher, and the rotation movement pattern can be produced at a small stimulus source intensity. Taking the stimulus source as the light source as an example, Figure 12 shows the light intensity and Schematic illustration of the effect of spot size on the motion mode of the fiber actuator. The effect of spot irradiation position and light intensity on the movement mode; Figure a shows that the spot is irradiated at the connection between the fiber and the load, and there is no continuous movement under low light intensity. When the light intensity reaches a certain size, the width of the spot is small, and the light When the light intensity is small, it produces tilting motion, and when the light intensity increases, it can produce rotation and tilting compound motion. Figure b shows that when the light spot is irradiated on the non-connected part of the fiber and the load, only rotational motion will be generated under low light intensity and small spot width. When the light intensity is large and the spot size is wide, a composite mode of rotational motion and up-and-down motion can be generated. In large When the light intensity is moderate and the spot size is moderate, there will be up and down motion.

In the fourth aspect, this solution provides a method for spontaneously generating periodical and continuous composite mechanical motion of an optically controlled fiber actuator, in which the load is suspended at the end of the fiber actuator, wherein the material of the fiber actuator is a photodeformable material. When stimulated by the driving light source, the linear structure will experience bending, torsion, curling and contraction of the curled fiber, and finally become a helical structure. The light fiber actuator forms a spot radiation area, adjusts the irradiation position or illumination of different driving light sources, and drives the fiber to execute The device produces compound mechanical motion.

The composite mechanical motion includes the composite of tilting motion and rotational motion. At this time, the part where the illuminated fiber actuator is connected to the load, and the part where the illuminated fiber actuator is not connected to the load, drives the fiber actuator to generate composite mechanical motion. The amplitude of the tilting motion is ±0~±90°, and the frequency is 0.01~100Hz. The amplitude of the rotational motion is ±0˜±1000°, and the frequency is 0˜10 Hz. In this solution, the composite spontaneous periodic continuous mechanical behavior of rotating motion and tilting motion can be adjusted by adjusting the irradiation position and intensity of the light source.

The composite mechanical motion includes the composite of up and down motion and rotation motion. At this time, the amplitude of the up and down motion mode is ±0~±2m, and the frequency is 0~100Hz at the part where the light fiber actuator is not connected to the load. The amplitude of the rotary motion is ±0~±1000°, and the frequency is 0~10Hz. The method realizes the composite spontaneous periodic continuous mechanical behavior of rotational motion and up-and-down motion mode by adjusting the irradiation position and intensity of the light source.

In order to carry out follow-up experimental operation to this scheme, therefore provide preparation example 1:

According to RM82:DODT is 1.67:1, DODT:PETMP is the molar ratio of 3:1, the mass ratio of graphene is 2%, guarantees that the monomer ratio of carbon-carbon double bond and thiol group is 1:1 monomer Mix and dissolve in chloroform, ultrasonically disperse for 4 hours, add 2wt% DPA to the mixed solution as a catalyst, shake and dissolve, fill the precursor solution into the threaded mold by capillary force, react at room temperature for 2 hours, carefully Strip off from the mold to obtain the incompletely crosslinked helical fiber precursor; the prepared incompletely crosslinked helical fiber is obtained by stretching and untwisting to obtain a straight fiber, and the straight fiber is continued to be stretched by 50% and fixed for 24h to make the sulfur Alcohols and olefins are fully cross-linked and cured to obtain multi-degree-of-freedom fiber actuators with uniaxial orientation.

Specifically, the fiber actuator obtained in Example 1 will be prepared as follows for experimental description:

Example 1: Light-controlled fiber actuators produce spontaneous, periodic and continuous mechanical motion Behavior systems produce tilting motions under light stimulation:

Hang a load under the fiber actuator (2.5 cm in length) obtained in Preparation Example 1, and irradiate the joint between the fiber and the load with a near-infrared light source, wherein the spot size of the near-infrared light source is 10 mm × 0.8 mm, and the light intensity is 3.5 W cm ^-2 .

Results: As shown in Figure 3, after turning on the near-infrared light source, the load at the lower end of the fiber actuator produced a continuous tilting motion, with a frequency and amplitude of 15 Hz and ±8°, respectively. The lower diagram of Fig. 1 shows the variation of the inclination angle of the fiber actuator.

Example 2: Optical control fiber actuator produces spontaneous, periodic and continuous mechanical motion behavior system produces rotational motion under light stimulation:

Repeat the experiment of Example 1, the difference is that the near-infrared light source is irradiated at the non-connected part of the fiber and the load,

Results: As shown in Figure 4, after turning on the near-infrared light source, the load at the lower end of the fiber actuator produced continuous rotational motion with a frequency and amplitude of 2.3 Hz and ±53°, respectively.

Example 3: The optical control fiber actuator produces spontaneous and periodic continuous mechanical movement behavior system produces up and down movement under light stimulation:

The experiment of Example 1 was repeated, except that the near-infrared light source was irradiated at the non-connected part of the fiber and the load, and the near-infrared light intensity was 5.0 W cm ⁻² .

Results: As shown in Figure 5, after turning on the near-infrared light source, the load at the lower end of the fiber actuator produces continuous up and down motion, with a frequency and amplitude of 12.5 Hz and ±1.5 mm, respectively.

Example 4: The optical control fiber actuator produces spontaneous, periodic and continuous mechanical motion behavior The system produces a composite spontaneous periodic and continuous mechanical behavior of tilting motion and rotational motion under light stimulation:

Repeat the experiment of Example 1, the difference is that the near-infrared light intensity is 4.5W cm ^-2 , and the light spot is irradiated on the connection part between the fiber and the load.

Results: As shown in Figure 6, after the near-infrared light source is turned on, the load at the lower end of the fiber actuator produces a composite spontaneous periodic continuous mechanical behavior of tilting motion and rotational motion, and the frequency and amplitude of the rotational motion are 1.9 Hz and ±50°, respectively. Tilting motion frequency and amplitude were 14 Hz and ±12°, respectively.

Example 5: The optical control fiber actuator produces spontaneous, periodic and continuous mechanical motion behavior The system produces a composite spontaneous periodic and continuous mechanical behavior of up and down motion and rotational motion under light stimulation:

The experiment in Example 1 was repeated, except that the spot size of the near-infrared light source was 15mm×0.8mm, the intensity of the near-infrared light was 4.5W cm ^-2 , and the light source was irradiated on the non-connected part of the fiber and the load.

Results: As shown in Figure 7, after the near-infrared light source is turned on, the load at the lower end of the fiber actuator produces a composite spontaneous periodic continuous mechanical behavior of up and down motion and rotational motion. The frequency and amplitude of the rotational motion are 0.48Hz and ±75°, respectively. Up and down movement frequency and amplitude are 8.5Hz and ±1.1mm respectively

Example 6: Optically controlled fiber actuators on the fluid interface generate spontaneous, periodic and continuous mechanical motion Behavioral systems generate rotational motion under light stimulation:

Repeat the experiment of Example 1, except that the load at the lower end of the actuator is immersed in the liquid or on the gas-liquid interface.

The results are shown in Figure 8. After the near-infrared light source is turned on, the fiber actuator can drive the load suspended at the lower end to produce continuous rotational motion at the fluid interface and in the fluid under light stimulation.

Example 7: Optical control fiber actuator produces spontaneous, periodic and continuous mechanical motion Behavior system produces tilting motion under the stimulation of concentrated sunlight:

The experiment of Example 1 was repeated, except that the light source used was concentrated sunlight with a light intensity of about 3.5 W cm ⁻² . Concentrated sunlight is produced by directly irradiating sunlight on a Fresnel lens with a diameter of 20cm and a focal length of 12.5cm.

Results: As shown in Figure 9: the fiber actuator can produce continuous tilting motion under the irradiation of concentrated sunlight.

Embodiment 8: Application of optical control fiber actuator to generate spontaneous, periodic and continuous mechanical motion behavior system for laser guidance

An optical reflector (the length of the fiber is 2.5cm, and the diameter of the small disc is 1cm) is suspended at the lower end of the fiber actuator obtained in Preparation Example 1, and one or more beams of laser light are irradiated on the optical reflector to form light reflection, and then Irradiating the fiber actuator with near-infrared light produces continuous mechanical motion behavior, thereby changing the path of light or spot trajectory.

Results: As shown in Figure 10: According to the first, second and fourth embodiments, the mechanical motion mode is adjusted to obtain tilting motion, rotational motion and complex spontaneous, periodic and continuous mechanical motion. The paths of reflected light in these three modes are as follows Shown in d/e/f in Figure 8.

Embodiment 9: Optical control fiber actuator produces spontaneous, periodic and continuous mechanical motion behavior system for energy harvesting device

A cylindrical NdFeB magnetic rod (fiber length is 2.5cm, magnetic rod length is 1cm) is suspended at the lower end of the fiber actuator obtained in Preparation Example 1, and a circular copper coil is used to surround the magnetic rod (coil diameter is about 1cm). ) The two leads of the copper coil are connected to a microcurrent sensor, and then the fiber actuator is irradiated with near-infrared light to drive the magnetic bar to produce continuous up and down motion.

Results: As shown in Figure 11: when the magnetic bar moves up and down, it will cut the magnetic induction line, generate a current signal, realize the conversion of light energy into mechanical energy and then into electrical energy, and realize the capture of light energy.

The present invention is not limited to the above-mentioned best implementation mode, anyone can draw other various forms of products under the inspiration of the present invention, but no matter make any changes in its shape or structure, all those with the same or similar features as the present application Approximate technical solutions all fall within the protection scope of the present invention.

Claims

A method for spontaneously generating periodic continuous mechanical motion of an optically controlled fiber actuator, characterized in that it includes the following steps: suspending a load on the end of the fiber actuator, driving a light source to irradiate any position of the fiber actuator, wherein the fiber actuator The raw material is a light-responsive material that is doped or bonded with light-to-heat conversion. It is molded into a spring-shaped fiber through a thread structure mold and then stretched into a straight state to obtain an optically controlled fiber actuator; under the stimulation of the driving light source, the fiber actuator can be transformed into a linear structure undergoes bends, twists, curls, and the contraction of its coiled fibers transforms into a helical structure.
The method for spontaneously generating periodic continuous mechanical motion of an optically controlled fiber actuator according to claim 1, characterized in that the fiber actuator is prepared in the following manner: a monomer containing a liquid crystal element and a material containing light-to-heat conversion are passed through The way of bonding or doping is through enol click reaction, Michael addition reaction or free radical polymerization in a mold with a helical structure, and the incompletely crosslinked helical fiber precursor is obtained by peeling off; the incompletely crosslinked The helical fiber precursor is stretched and untwisted to obtain a straight fiber, and the shape and orientation are fixed after the straight fiber is stretched to a set ratio.
According to claim 1, the method for spontaneously generating periodic and continuous mechanical motion of an optically controlled fiber actuator is characterized in that changing the light intensity of the driving light source, the spot size and the irradiation position drives the fiber actuator to generate different mechanical motion modes, including tilting at least one of motion, rotational motion, and up and down motion.
The method for spontaneously generating periodic continuous mechanical motion of an optical fiber actuator according to claim 3, characterized in that, when the driving light source irradiates the connection between the fiber actuator and the load, the fiber actuator is driven to generate continuous tilting motion, tilting The amplitude of the movement is ±0~±90°, and the frequency is 0~100Hz.
The method for spontaneously generating periodic and continuous mechanical motion of an optical fiber actuator according to claim 3, characterized in that when the driving light source irradiates the non-connected part of the fiber actuator and the load, the amplitude of the rotational motion is ±0～± 1000°, the frequency is 0~10Hz; when the driving light source irradiates the non-connected part of the fiber actuator and the load, the driving fiber actuator produces continuous up and down motion, the amplitude of the up and down motion is ±0~±2m, and the frequency is 0~ 100Hz.
According to claim 3, the method for spontaneously generating periodic continuous mechanical motion of an optically controlled fiber actuator is characterized in that the irradiation position or illumination of different driving light sources is adjusted, and the fiber actuator is driven to generate a composite mechanical motion, wherein the composite mechanical motion includes tilting Combination of movement and rotation, and combination of up and down and rotation.
The method for spontaneously generating periodical continuous mechanical motion of an optical fiber actuator according to claim 1, characterized in that the load is placed in various gas environments and high damping liquid environments.
The method for spontaneously generating periodical continuous mechanical motion of an optical fiber actuator according to claim 1, characterized in that the load is a magnetic rod placed in the coil, and the light source is driven to drive the magnetic rod to generate up and down motion and cut the magnetic induction line to generate current .
The method for spontaneously generating periodic continuous mechanical motion of an optical fiber actuator according to claim 1, wherein the load is an optical mirror, and the driving light source drives the optical mirror to produce different modes of motion. When the laser beam irradiates on the optical When the mirror is on, the laser beam is steered or realizes linear and waveform light scanning.
A system in which an optical fiber actuator spontaneously generates periodic continuous mechanical motion, characterized in that it includes:

Fiber actuators, wherein the fiber actuators are prepared by doping or bonding photoresponsive materials for photothermal conversion, and under the stimulation of the driving light source, the linear structure undergoes bending, twisting, curling and contraction of the curled fiber to transform into a helical structure;

a load, suspended from the end of the fiber actuator; and

The driving light source is used for illuminating the fiber actuator to drive the fiber actuator to spontaneously generate periodic continuous mechanical motion.