Self-excited burst light drive structure and self-control method thereof

Abstract

The present invention relates to the technical field of light-driven structure design, which solves the technical problem that traditional burst structures stop after a single burst and need to rely on manual or electrical signal triggering to reset, making it difficult to achieve continuous autonomous action. In particular, it relates to a self-excited burst light-driven structure and its self-control method, and the light-driven structure includes a protective shell, a control component, and a fixing part. The liquid crystal elastomer sheet in the composite sheet has a photothermal response characteristic, and when subjected to external photothermal stimulation, it will shrink and deform, driving the free end of the composite sheet to bend to one side and enter the non-illuminated area, and then dissipate heat to recover and re-enter the illuminated area to achieve a self-sustaining process. The present invention can maintain an autonomous, multiple, and continuous burst process under constant light stimulation, and has the advantages of simple structure, sensitive response, and energy self-sustaining. It provides a new solution for the development of efficient and autonomous light-driven burst devices, showing greater research value and application potential.

Description

Technical Field

[0001] The present invention relates to the technical field of light-driven structure design, and in particular to a self-excited burst light-driven structure and a self-control method thereof. Background Art

[0002] Explosive structures can release energy and achieve rapid motion response in a short period of time under external stimulation or internal feedback. They are typically based on thermal stimulation or chemical reactions, achieving energy release through internal irreversible phase changes. Typical applications include thermally driven micro-exploders and chemical fuel propulsion systems. These drive systems, due to their rapid response, compact structure, and high drive efficiency, are suitable for scenarios requiring high motion precision and energy release speed, such as military fuses, industrial safety devices, and biomedical fields.

[0003] Currently, single-shot burst structures have attracted widespread attention due to their high precision, rapid response, and strong stability. However, their core limitation is the difficulty in achieving autonomous reset after the burst. They often rely on manual or electrical signal triggering, resulting in an inability to continuously and autonomously repeat the action, limiting their stability and reliability in complex dynamic environments.

[0004] Liquid crystal elastomers (LCEs), as materials with controllable deformation properties, undergo shape changes in response to light or temperature. This property can be exploited to achieve autonomous control of explosive structures, offering broad application prospects in fields such as sensors, automated control, and electronic devices. However, existing technologies have not fully exploited the deformation properties of LCEs to implement self-excited explosive control systems. These technologies are often unsustainable and require external intervention, limiting their application in dynamic environments. Summary of the Invention

[0005] In response to the shortcomings of the existing technology, the present invention provides a self-excited burst light drive structure and its self-control method, which solves the technical problem that the traditional burst structure stops after a single burst and needs to rely on manual or electrical signal triggering to reset, making it difficult to achieve continuous autonomous action.

[0006] To solve the above technical problems, the present invention provides the following technical solution: a self-control method for a self-excited burst light-driven structure, the method comprising the following steps:

[0007] S1. Calculate the light-driven curvature of a liquid crystal elastomer sheet under uniform illumination ;

[0008] S2, based on light-driven curvature Calculating the tensile force generated by a thin liquid crystal elastomer plate under photothermal actuation ;

[0009] S3. Obtaining the contraction strain of the liquid crystal elastomer sheet under photothermal drive and temperature change the relationship between;

[0010] S4, based on shrinkage strain and temperature change The relationship between the internal temperature of the liquid crystal elastomer sheet in the light area is obtained. Over time The equation of change is:

[0011] ;

[0012] And, the internal temperature of the liquid crystal elastomer sheet in the non-illuminated area Over time The equation of change is:

[0013] ;

[0014] Where, represents the extreme temperature difference of the liquid crystal elastomer sheet corresponding to the photothermal response; is the thermal relaxation time;

[0015] S5, combine steps S1 and S4 to establish a method for adjusting the light and heat intensity. To change the critical control equation of the working state and realize the regulation of the autonomous jump process of the light-driven structure.

[0016] Furthermore, in step S1, it includes:

[0017] S11. Calculate the torque generated by a thin liquid crystal elastomer plate under light , the calculation formula is:

[0018] ;

[0019] Where, is the thickness of the composite sheet; The non-uniform light-driven contraction strain of a liquid crystal elastomer sheet along the thickness direction under illumination; is the elastic modulus of the liquid crystal elastomer sheet; Indicates the thickness variable of the liquid crystal elastomer sheet in the integration process from arrive integral;

[0020] S12. Define that the light irradiated on the liquid crystal elastomer sheet is uniform and obtain the light-driven curvature The expression is:

[0021] ;

[0022] S13, torque Substitute into step S12 to obtain the light-driven curvature of the liquid crystal elastomer sheet under uniform light ,Right now:

[0023] ;

[0024] Where, is the principal moment of inertia of the cross section of the liquid crystal elastomer thin plate.

[0025] Furthermore, in step S2, the tension The calculation formula is:

[0026] ;

[0027] Where, is the displacement of the free end of the composite plate; is the height of the liquid crystal elastomer sheet; is the elastic modulus of the liquid crystal elastomer sheet; is the principal moment of inertia of the cross section of the liquid crystal elastomer thin plate.

[0028] Further, in step S3, the contraction strain and temperature change The relationship between them is:

[0029] ;

[0030] Where, is the shrinkage coefficient of the liquid crystal elastomer sheet.

[0031] Furthermore, in step S4, it includes:

[0032] S41, according to the shrinkage strain and temperature change The relationship between the temperature change of the liquid crystal elastomer sheet at room temperature is obtained. The expression is:

[0033] ;

[0034] Where, is the absolute temperature of the liquid crystal elastomer sheet; is the ambient temperature at normal temperature;

[0035] S42. Specific heat capacity of liquid crystal elastomer sheet obtained by measurement , heat transfer coefficient and the intensity of light and heat received ;

[0036] S43, given thermal relaxation time , solve the temperature change of the liquid crystal elastomer sheet under light The expression is:

[0037] ;

[0038] S44: Based on step S43, the internal temperature of the liquid crystal elastomer sheet in the illumination area is obtained. Over time The equation of change, and the internal temperature in the non-illuminated area Over time The changing equation.

[0039] Furthermore, in step S5, the critical control equation is expressed as:

[0040] ;

[0041] Where, is the magnetic attraction force of the right magnet; is the magnetic attraction force of the left magnet; is the force of contraction of the liquid crystal elastomer sheet under light illumination; is the force of the liquid crystal elastomer sheet to recover in the absence of light; is the shrinkage coefficient of the liquid crystal elastomer sheet; is the distance between the right and left magnets; is the height of the liquid crystal elastomer sheet; is the elastic modulus of the liquid crystal elastomer sheet; is the principal moment of inertia of the cross section of the liquid crystal elastomer thin plate.

[0042] The present invention also proposes another technical solution: a light-driven structure that utilizes the self-control method to achieve a continuous, periodic, and autonomous hopping process under illumination conditions, and the hopping frequency can be changed by adjusting the parameters of the light-driven structure;

[0043] The light driving structure includes a light-transmitting hole provided on the protective shell, and a control component provided in the protective shell;

[0044] The control assembly includes a composite thin plate with one end fixed inside the protective shell, and a left magnet and a right magnet that are detachably fixed to the two sides of the protective shell, respectively. A metal block is fixed to the free end of the composite thin plate at the same height as the right magnet.

[0045] When the composite sheet is in an initial state without bending, the metal block and the right magnet are in contact and fixed by magnetic attraction force, thereby being in a static equilibrium state. The composite sheet includes a liquid crystal elastomer sheet with photothermal response characteristics and an inert layer tightly bonded to the liquid crystal elastomer sheet.

[0046] When strong enough light from the outside shines through the light-transmitting hole onto the liquid crystal elastomer sheet, the composite sheet undergoes photothermal deformation and bends in the illuminated area, pulling the metal block away from the right magnet and instantly jumping to the left side to contact the left magnet and be fixed by magnetic attraction.

[0047] At this time, the light is blocked by the bent inert layer and the liquid crystal elastomer sheet is in the non-illuminated area. The liquid crystal elastomer sheet gradually dissipates heat and cools down in the non-illuminated area to restore the previous photothermal deformation. The elastic force generated drives the metal block to jump toward the right magnet and contact it again. The liquid crystal elastomer sheet enters the illuminated area again to realize the autonomous reciprocating alternating jumping process.

[0048] Furthermore, the left magnet and the right magnet are detachably mounted on the protective shell via a fixing member, and the fixing member is adapted to left magnets or right magnets of different sizes and can be assembled, disassembled, and fixed.

[0049] The present invention also proposes another technical solution: a light intensity monitoring device, which utilizes the above-mentioned light drive structure to produce different feedback effects according to different degrees of external disturbance, thereby realizing monitoring or judging the external light intensity condition;

[0050] The light intensity monitoring device includes a first fixing plate fixed to a protective housing, and a first lightweight insulating rod having one end fixed to a metal block. The first fixing plate is mounted with a light source whose circuit is turned on and off by a normally open switch. The normally open switch is mounted in the protective housing and corresponds to the free end of the first lightweight insulating rod.

[0051] Under lighting conditions, the light-driven structure drives the first lightweight insulating rod to bounce back and forth in the left and right directions inside the protective shell. When the first lightweight insulating rod hits the normally open switch, the switch closes to form a closed loop to make the lamp light up.

[0052] Furthermore, the light source generates periodic flickering along with the self-controlled jump process of the light driving structure, so as to monitor or judge the external light intensity condition.

[0053] By means of the above technical solution, the present invention provides a self-excited burst light driving structure and a self-control method thereof, which have at least the following beneficial effects:

[0054] 1. The light-driven structure proposed in this invention periodically absorbs energy and maintains autonomous, multiple, and continuous bursts under constant light stimulation to achieve a jumping process. This can overcome the traditional single-burst structure that relies on manual reset and does not require additional complex controllers and portable batteries. It has the advantages of simple structure, sensitive response, and self-sustaining energy. It provides a new solution for the development of efficient and autonomous light-driven burst devices, and is expected to promote the development of sensors, electronic equipment, automated control and other fields, realizing greater research value and application potential.

[0055] 2. The light-driven structure proposed in this invention, combined with a self-control method, can produce a continuous, periodic bursting process under stable lighting conditions. The frequency of the bursting can be varied by adjusting the system parameters of the light-driven structure. This can also reduce the limitations of the application of new materials in the design of self-excited burst structures, making operation more stable. Autonomous burst control can be achieved without additional human effort, enabling the integration of the controller and external devices, as well as automatic control of electrical appliances.

[0056] 3. The structural design of this invention allows the influence of gravity on the metal block to be ignored. The attraction of the left and right magnets to the metal block is adjustable, and the length, width, and thickness of the liquid crystal elastomer sheet can be selected according to different application scenarios. Therefore, the parameters of the liquid crystal elastomer sheet can be customized to meet specific needs. This flexibility enables the self-excited burst light drive structure to adapt to various applications, achieving more layout options, parameter flexibility, and performance optimization to meet diverse needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0058] Figure 1 This is a schematic diagram of the light driving structure in the first embodiment of the present invention in an initial state without providing light;

[0059] Figure 2 Schematic diagram of the light driving structure in the first embodiment of the present invention when providing light;

[0060] Figure 3 Schematic diagram of the light-driven structure in the first embodiment of the present invention when it is reset after being illuminated;

[0061] Figure 4 This is a front view of the optical drive structure in Example 1 of the present invention;

[0062] Figure 5 for Figure 1 A magnified schematic diagram of area A in the middle;

[0063] Figure 6 This is a diagram of the trajectory of the metal block in the second embodiment of the present invention;

[0064] Figure 7 This is a trajectory diagram of the metal block stationary on the right side in the second embodiment of the present invention;

[0065] Figure 8 Schematic diagram of the alternating frequency of the metal block's jumping state under different light intensities in the second embodiment of the present invention;

[0066] Figure 9 Schematic diagram of the structure of the light intensity monitoring device in the third embodiment of the present invention;

[0067] Figure 10 for Figure 9 A magnified schematic diagram of area B in the middle;

[0068] Figure 11 Schematic diagram of the flickering frequency of the light source under different light intensities in Example 3 of the present invention;

[0069] Figure 12 This is a schematic diagram of the structure of the self-excited impact bell design in the fourth embodiment of the present invention;

[0070] Figure 13 for Figure 12 Schematic diagram of the enlarged area C in the middle.

[0071] In the picture:

[0072] 1. Protective shell; 11. Fixing slot; 12. Light hole;

[0073] 2. Control assembly; 21. Left magnet; 22. Right magnet; 23. Metal block; 24. Composite sheet; 241. Inert layer; 242. Liquid crystal elastomer sheet;

[0074] 3. Fixing member; 31. First fixing bolt; 32. First adjustable fixing clamp; 33. First thumb screw; 34. Second thumb screw; 341. Bolt; 342. Countersunk screw; 343. Fixing washer; 35. Second adjustable fixing clamp; 36. Second fixing bolt;

[0075] 4. The first lightweight insulating rod;

[0076] 5. Light intensity monitoring device; 51. First fixing plate; 52. First flat-head screw; 53. Wire conduit; 54. Light source; 55. Lampshade; 56. Second flat-head screw; 57. Wire; 58. Power supply; 59. Normally open switch;

[0077] 6. Second lightweight insulating rod;

[0078] 7. Metal bell component; 71. Second fixing plate; 72. Third flat head screw; 73. Metal bell; 74. Fourth flat head screw. DETAILED DESCRIPTION

[0079] To make the above-mentioned objectives, features, and advantages of the present invention more clearly understood, the present invention is further described below in detail with reference to the accompanying drawings and specific embodiments. This will enable a full understanding of how this application uses technical means to solve technical problems and achieve technical effects, and to implement the invention accordingly.

[0080] Example 1

[0081] The liquid crystal elastomer used in this embodiment is an intelligent material composed of cross-linked liquid crystal units, exhibiting liquid crystal anisotropy and rubber elasticity. When subjected to external light and heat stimulation, the liquid crystal elastomer undergoes a multi-domain to single-domain transition due to the internal liquid crystal units, resulting in macroscopic contraction and deformation. Based on this characteristic of liquid crystal elastomers, this embodiment proposes a self-excited burst light-driven structure composed of liquid crystal elastomers. This light-driven structure can achieve autonomous control of its motion state under stable light conditions, forming a continuous, periodic, and autonomous burst process.

[0082] Please refer to the attached Figure 1-Figure 5 The optical drive structure of this embodiment includes a protective housing 1, a control assembly 2, and a fixing member 3. The core control assembly 2 is composed of a left magnet 21, a right magnet 22, a metal block 23, and a composite sheet 24. The fixing member 3 includes a first fixing bolt 31, a second fixing bolt 36, a first adjustable fixing clamp 32, a second adjustable fixing clamp 35, a first thumbscrew 33, and a second thumbscrew 34.

[0083] The composite sheet 24 of this embodiment is one of the core components, including a liquid crystal elastomer sheet 242 and an inert layer 241. The liquid crystal elastomer sheet 242 and the inert layer 241 have the same thickness, length, width, elastic modulus and Poisson's ratio. They are bonded and fixed with UV moisture dual-curing glue and will not slide relative to each other.

[0084] In this embodiment, the second fixing bolt 36 is used to fix the left magnet 21 on the left side of the protective shell 1. The first fixing bolt 31 is used to fix the right magnet 22 on the right side of the protective shell 1, and the left magnet 21 and the right magnet 22 are at the same height. A fixing groove 11 is opened on the lower right side of the protective shell 1, and the composite sheet 24 is embedded in the fixing groove 11 to fix the lower end of the composite sheet 24. The left side of the composite sheet 24 is a liquid crystal elastomer sheet 242, and the right side is an inert layer 241. The free end of the composite sheet 24 is fixed to the metal block 23, so that the metal block 23 and the right magnet 22 are at the same height. When the composite sheet 24 is not bent, the metal block 23 at its free end just contacts the right magnet 22 and is fixed by the right magnet 22.

[0085] In this embodiment, the liquid crystal elastomer sheet 242 has photothermal responsive properties. When exposed to external light and heat stimulation, it contracts and deforms, and the free end of the composite sheet 24 bends toward the liquid crystal elastomer sheet 242. A light-transmitting hole 12 is formed on the front side of the protective case 1, with a length and width equal to the height and width of the composite sheet 24.

[0086] In this embodiment, unthreaded through holes for fitting the first fixing bolt 31 and the second fixing bolt 36 are respectively provided at the same height in the middle of the left and right sides of the protective shell 1 , and their heights are the same as the heights of the free ends of the composite sheet 24 after being fixed.

[0087] In this embodiment, the first adjustable fixing clamp 32 and the second adjustable fixing clamp 35 are used to fix the right magnet 22 and the left magnet 21, respectively, so that they are located on the left and right sides of the protective shell 1. The first adjustable fixing clamp 32 and the second adjustable fixing clamp 35 are respectively connected to the first thumb screw 33 and the second thumb screw 34 of the same structure by threading. Figure 5 As shown, this embodiment uses the second thumbscrew 34 as an example to illustrate its structural composition. The second thumbscrew 34 is formed by threading a threaded hole in a bolt 341 and threading a countersunk screw 342 with a fixing washer 343 mounted on the bottom thereof into the bolt 341. By adjusting the amount of threading of the second thumbscrew 34 into the second adjustable fixing clamp 35, the fixing washer 343 at the bottom of the countersunk screw 342 can be tightened and clamped against the right magnet 22 on the second adjustable fixing clamp 35, or separated to remove the right magnet 22, thereby enabling the placement of magnets of different sizes and easy assembly and disassembly.

[0088] In this embodiment, a fixing groove 11 is formed on the lower right side of the inner wall of the protective shell 1. The length and width of the fixing groove 11 are the same as those of the composite sheet 24. The right edge of the fixing groove 11 and the left end of the right magnet 22 are aligned on the same vertical line. The composite sheet 24 is fixed to the fixing groove 11 in the protective shell 1 using UV-moisture dual-curing adhesive. The metal block 23 is then attached to the free end of the top of the composite sheet 24 using UV-moisture dual-curing adhesive.

[0089] The working principle of the optical drive structure of this embodiment is as follows: when light does not pass through the light-transmitting hole 12 on the protective shell 1, the interaction between the composite sheet 24, the metal block 23 and the right magnet 22 causes the metal block 23 to be in a static equilibrium state in the initial state, at which time the metal block 23 is in stable contact with the right magnet 22; when light passes through the light-transmitting hole 12 on the protective shell 1, the light source irradiates the liquid crystal elastomer sheet 242 on the left side of the composite sheet 24, thereby causing the liquid crystal elastomer sheet 242 to shorten. Since the inert layer 241 on the right side does not shorten, when the force of the contraction of the liquid crystal elastomer sheet 242 on the left side is greater than that of the right magnet 2 When the adsorption force on the metal block 23 is applied, the composite sheet 24 bends and pulls the metal block 23 away from the right magnet 22. It then instantly jumps to the left, contacts the left magnet 21, and is attracted. At this point, the light source is blocked by the curved inert layer 241, leaving the left liquid crystal elastomer sheet 242 in a non-illuminated area. This allows the liquid crystal elastomer sheet 242 to gradually dissipate heat and cool down, restoring the previous photothermal deformation. The elastic force generated by the liquid crystal elastomer sheet 242 as it recovers its deformation drives the metal block 23 to jump toward the right magnet 22, ultimately bringing the metal block 23 back into contact with the right magnet 22 and allowing the composite sheet 24 to re-enter the illuminated area. This alternating process repeats, forming a continuous, periodic, and autonomous jumping process, resulting in a self-excited light-driven structure.

[0090] In this embodiment, the illuminated state refers to a state in which light is irradiated on the light driving structure through the light-transmitting holes 12 on the protective shell 1 , and the non-illuminated state refers to a state in which no light is irradiated on the light driving structure through the light-transmitting holes 12 on the protective shell 1 .

[0091] Furthermore, this embodiment adjusts the light and heat intensity To change the jump frequency of the working state, the critical control equation of the jump of the metal block 23 is realized based on the composite thin plate 24. The critical control equation is as follows:

[0092] ;

[0093] Where, is the magnetic attraction force of the right magnet; is the magnetic attraction force of the left magnet; is the force of contraction of the liquid crystal elastomer sheet under light illumination; is the force of the liquid crystal elastomer sheet to recover in the absence of light; is the thickness of the composite sheet; is the height of the liquid crystal elastomer sheet; is the distance between the left magnet and the right magnet; is the contraction coefficient of the liquid crystal elastomer; The liquid crystal elastomer sheet in the light area changes with time varying internal temperatures; The liquid crystal elastomer sheet in the non-illuminated area changes with time varying internal temperatures; is the thermal relaxation time; is the elastic modulus of the liquid crystal elastomer sheet.

[0094] By adjusting the parameters in the critical control equation and , the frequency of state alternation can be changed to achieve different control purposes. , Liquid crystal elastomer shrinkage coefficient When any of the two parameters is increased, the alternating frequency of the jump state is accelerated; on the contrary, if the above two parameters are reduced and For any one of them, the alternation frequency of the jump state will slow down.

[0095] Example 2

[0096] This embodiment further provides a method for designing a self-controlled self-excited burst optical drive structure based on the first embodiment. The method includes the design of an optical drive structure and a corresponding self-control method for controlling the autonomous tripping process of the self-excited burst optical drive structure proposed in the first embodiment. The method includes the following steps:

[0097] S101, prepare and assemble the optical drive structure. The optical drive structure prepared can be the optical drive structure in Example 1. The method for preparing and assembling the optical drive structure is: prepare a protective shell 1, a control component 2, a fixing part 3 and other required parts, including a left magnet 21, a right magnet 22, a metal block 23 and a composite sheet 24. The fixing part 3 is divided into a first fixing bolt 31, a second fixing bolt 36, a first adjustable fixing clamp 32, a second adjustable fixing clamp 35, a first thumb screw 33 and a second thumb screw 34. The composite sheet 24 is prepared using a liquid crystal elastomer sheet 242 and an inert layer 241, and bonded with UV moisture dual-curing glue. A fixing groove 11 with the same length and width as the composite sheet 24 is opened on the lower right side of the protective shell 1, and the right edge of the fixing groove 11 is on the same plumb line as the left end of the right magnet 22. The composite sheet 24 is fixed in the fixing groove 11 with UV moisture dual-curing glue. Attach metal block 23 to the free end of composite sheet 24 using UV / moisture dual-cure adhesive, with the height of metal block 23 centered between right magnet 22. Attach the threaded ends of the left and right magnets to the left and right inner through-holes of protective shell 1 and secure with countersunk screws 342. Attach the light source to the upper left corner of protective shell 1 using UV / moisture dual-cure adhesive. When the light source is operating, it will illuminate the liquid crystal elastomer sheet 242 with uniform light, triggering the contraction of the liquid crystal elastomer. Ensure that all components are correctly installed and securely connected to achieve the desired self-controlled optical drive structure.

[0098] S102. When no light source is provided, the interaction between the composite sheet 24, the metal block 23, and the right magnet 22 causes the metal block 23 to be in a static equilibrium state in its initial state. At this point, the metal block 23 is in stable contact with the right magnet 22 and, supported by the composite sheet 24, does not slide down. When light source is provided, the light shines on the left liquid crystal elastomer sheet 242, causing its temperature T to rise, causing it to begin to contract and deform, generating a tensile force. When the force of the deformation and contraction of the left liquid crystal elastomer sheet 242 exceeds the attraction force of the right magnet 22 on the metal block 23, the composite sheet 24 bends and pulls the metal block 23 away from the right magnet 22, instantly jumping to the left to contact and be attracted by the left magnet 21.

[0099] S103: Length of the liquid crystal elastomer sheet 242 in the initial state , the distance between the left end of the right magnet 22 and the right end of the left magnet 21 Determining the shrinkage strain of the liquid crystal elastomer sheet 242 during photothermal contraction , the tension of the liquid crystal elastomer sheet 242 The critical control equation of the vibration of the metal block 23 is obtained.

[0100] In order to calculate the elastic force of the liquid crystal elastomer sheet 242, the present embodiment first needs to find the light-driven curvature of the liquid crystal elastomer sheet 242. Considering that one side of the liquid crystal elastomer sheet 242 is always illuminated by light at the same time, in order to simplify the modeling, it is assumed that the liquid crystal elastomer sheet 242 is illuminated uniformly. The torque generated by the illuminated liquid crystal elastomer sheet 242 is , then the light-driven curvature The calculation formula is:

[0101] ;

[0102] in, is the elastic modulus of the liquid crystal elastomer sheet; is the principal moment of inertia of the cross section of the liquid crystal elastomer thin plate.

[0103] The non-uniform light-driven contraction strain of the liquid crystal elastomer sheet 242 under illumination along the thickness direction is expressed as , then the moment in formula (1) It can be expressed as:

[0104] ;

[0105] Where, is the thickness of the composite sheet; Indicates that the thickness variable of the liquid crystal elastomer sheet in the integration process changes from arrive integral.

[0106] Substituting formula (2) into formula (1) we can obtain:

[0107] ;

[0108] The degree of deformation of an object changes with temperature, and the rate of change is determined by the coefficient of contraction. Determine the contraction strain of the liquid crystal elastomer sheet 242 under the photothermal drive in formula (2) and temperature change The relationship between them is as follows:

[0109] ;

[0110] In the model constructed in this embodiment, the moment generated by the composite sheet 24 is , can be calculated according to formula (5):

[0111] ;

[0112] in, is the tensile force of the liquid crystal elastomer sheet; is the height of the liquid crystal elastomer sheet.

[0113] According to the geometric relationship and deflection equation of the crystal elastic thin plate in the figure, we can obtain:

[0114] ;

[0115] in, is the displacement of the free end of the composite sheet (i.e., the metal block). The tension of the liquid crystal elastomer sheet 242 under photothermal drive Calculate according to formula (7), which is as follows:

[0116] ;

[0117] According to the tensile force obtained in formula (7) By comparing the magnetic attraction force of the right magnet 22 Tension with liquid crystal elastomer sheet 242 The critical condition for the metal block 23 to jump to the left can be obtained in this embodiment, namely:

[0118] ;

[0119] At the same time, by comparing the magnetic attraction force of the left magnet 21 Tension with liquid crystal elastomer sheet 242 The critical condition for the metal block 23 to be reset can be obtained in this embodiment, namely:

[0120] ;

[0121] S104, first record the ambient temperature at room temperature (Assuming that the temperature of the liquid crystal elastomer sheet 242 at room temperature is equal to the ambient temperature), measure the specific heat capacity of the liquid crystal elastomer sheet 242 and heat transfer coefficient , light and heat intensity , thereby obtaining the internal temperature of the liquid crystal elastomer sheet 242 in the illumination area Over time The equation of change and the internal temperature in the non-illuminated area Over time The changing equation.

[0122] In formula (4), the temperature change of the liquid crystal elastomer sheet 242 is Calculate according to formula (10), which is as follows:

[0123] ;

[0124] in, is the absolute temperature of the liquid crystal elastomer sheet.

[0125] Therefore, under light, the temperature change It can be expressed as follows:

[0126] ;

[0127] Given thermal relaxation time , formula (11) can be further derived as:

[0128] ;

[0129] In formula (12), thermal relaxation time refers to the time required for a substance to reach thermal equilibrium. It usually refers to the time required for an object to reach the final temperature from the initial temperature in a thermal gradient. The larger the value, the longer it takes to reach the temperature change of the liquid crystal elastomer sheet 242 corresponding to the photothermal response.

[0130] By solving formula (12), the temperature variation equations of the liquid crystal elastomer sheet 242 in the illuminated area and the non-illuminated area and the corresponding control equations are obtained, namely:

[0131] In the light-irradiated area, the internal temperature of the liquid crystal elastomer sheet 242 is Over time The equation of change is:

[0132] ;

[0133] in, It represents the extreme temperature difference of the liquid crystal elastomer sheet 242 corresponding to the photothermal response.

[0134] Then, the critical control equation for the metal block 23 to jump to the left in the illumination area is calculated according to formula (14), which is as follows:

[0135] ;

[0136] The internal temperature of the liquid crystal elastomer sheet 242 in the non-illuminated area is Over time The equation of change is:

[0137] ;

[0138] Then, the critical control equation for the metal block 23 to jump to the right in the non-illuminated area is calculated according to formula (16), which is as follows:

[0139] ;

[0140] According to the above content, the internal temperature of the liquid crystal elastomer sheet in the illumination area is obtained. Over time The equation of change and the internal temperature in the non-illuminated area Over time The changing equation.

[0141] S105, obtain the dynamic response of the liquid crystal elastomer sheet 242, that is, the position of the metal block 23 and the time If the center position of the metal block 23 in static equilibrium in the initial state is taken as the origin O, and a two-dimensional rectangular coordinate system is established with the horizontal left direction as the positive direction, the position of the metal block 23 can be used to determine whether the liquid crystal elastomer sheet 242 is in the illumination area. When the displacement of the metal block 23 When the liquid crystal elastic body sheet 242 is in the illumination area; when the displacement of the metal block 23 When , the liquid crystal elastomer sheet 242 is in the non-illuminated area. Based on this, the jumping rule of the metal block 23 can be obtained by calculation.

[0142] Therefore, the length of the liquid crystal elastomer in the initial state is , magnetic attraction force of right magnet , magnetic attraction force of left magnet , the distance between the left end of the right magnet and the right end of the left magnet Under constant conditions, the self-control state of the light-driven structure is related to the input light and heat intensity. related.

[0143] When the light and heat intensity When the tension generated by the liquid crystal elastomer sheet 242 is large enough, Sufficient to resist the magnetic attraction force of the right magnet 22 , and when restored, it is sufficient to resist the magnetic attraction force of the left magnet 21 Thus maintaining a continuous, periodic jump process, such as Figure 6 shown.

[0144] When the light and heat intensity is too low, the tension generated by the liquid crystal elastomer sheet 242 It is not enough to maintain the self-control process of the light-driven structure. The structure is in a static state, such as Figure 7 shown.

[0145] According to a design method for self-control of an optical drive structure of this embodiment, in order to simplify the problem, improve numerical stability, and achieve parameter comparison and versatility, the parameters in the above steps and the obtained calculation formula are dimensionless during the calculation process and numerical simulation calculations are performed using MATLAB software, namely:

[0146] All are dimensionless parameters.

[0147] In summary, this embodiment adjusts the parameters and , the frequency of state alternation can be changed to achieve different control purposes. , shrinkage coefficient of liquid crystal elastomer sheet If any of the two parameters is increased, the alternating frequency of the jump state will be accelerated; on the contrary, if the above two parameters are reduced and If any one of the two states is selected, the alternating frequency of the jump state will be slowed down. Figure 8 shown.

[0148] Example 3

[0149] This embodiment provides a technical solution: a light intensity monitoring device. Building on the second embodiment, a circuit loop is added to the exterior of the protective housing. This device generates different feedback effects when subjected to varying degrees of external disturbance, allowing for intuitive monitoring and assessment of external light intensity.

[0150] refer to Figure 9-10 The light intensity monitoring device 5 of this embodiment is fixed on the protective shell 1 to monitor the light intensity. The light intensity monitoring device 5 of this embodiment can be replaced by other electrical appliances such as buzzers and alarms as needed.

[0151] In this embodiment, a power supply 58 and a normally open switch 59 are arranged on the circuit, and a first lightweight insulating rod 4 is fixed to the metal block 23. A wire 57 is passed through a conduit 53 extending through the protective housing 1, connecting the power supply 58 to the light source 54. The light source 54 and lampshade 55 are fixed to the first fixing plate 51, which is then secured to the protective housing 1 using a first flat-head screw 52 and a second flat-head screw 56.

[0152] The light intensity monitoring device 5 of this embodiment operates as follows: When the device is exposed to light, light shines through the light-transmitting holes 12 in the protective housing 1 onto the liquid crystal elastomer sheet 242. When the light reaches a certain intensity, the metal block 23, similar to the second embodiment, drives the first lightweight insulating rod 4 to jump leftward within the protective housing 1. At this point, the liquid crystal elastomer sheet 242 leaves the illuminated area, gradually dissipating heat and cooling it, restoring the previous photothermal deformation. The composite sheet 24 then drives the metal block 23 to jump rightward. When the first lightweight insulating rod 4 strikes the normally open switch 59, the switch closes, completing a closed circuit and illuminating the light source 54. Simultaneously, the liquid crystal elastomer sheet 242 enters the illuminated area, repeating the above process to produce continuous, periodic flashing.

[0153] According to the dynamic response of the metal block 23 during the movement in the second embodiment, the dynamic response of the liquid crystal elastic body sheet 242 is obtained, that is, the position of the metal block 23 and the time If the center position of the metal block 23 in static equilibrium in the initial state is taken as the origin O, and a two-dimensional rectangular coordinate system is established with the horizontal left direction as the positive direction, the position of the metal block 23 can be used to determine whether the liquid crystal elastomer sheet 242 is in the illumination area. When the displacement of the metal block 23 When the liquid crystal elastic body sheet 242 is in the illumination area; when the displacement of the metal block 23 When , the liquid crystal elastomer sheet 242 is in the non-illuminated area.

[0154] According to formula (14) and formula (16), the jumping rule of the metal block 23 can be obtained, namely:

[0155] When in the illumination area, the metal block 23 is subjected to the tension from the liquid crystal elastomer sheet 242. Calculate according to formula (17), which is as follows:

[0156] ;

[0157] In the light area, when , that is, the tension of the liquid crystal elastomer sheet 242 Greater than the magnetic attraction force of the right magnet 22 At this time, the metal block 23 separates from the right magnet 22, driving the first lightweight insulating rod 4 to jump to the left in the protective shell 1.

[0158] In the non-illuminated area, the metal block 23 is subjected to the tension from the liquid crystal elastomer sheet 242. Calculate according to formula (18), which is as follows:

[0159] ;

[0160] In the non-illuminated area, when , that is, the tension of the liquid crystal elastomer sheet 242 Greater than the magnetic attraction force of the left magnet 21 At this time, the metal block 23 separates from the left magnet 21, driving the first lightweight insulating rod 4 to jump to the right in the protective shell 1.

[0161] In order to simplify the problem, improve numerical stability, and achieve parameter comparison and versatility, in combination with Example 2, the parameters in the above steps and the obtained calculation formulas were dimensionless during the calculation process and numerical simulation calculations were performed using MATLAB software.

[0162] Dimensional parameter assignment: ambient temperature ; Shrinkage coefficient Thermal relaxation time ;Thickness of composite sheet ; The height of the liquid crystal elastomer sheet ; Principal moments of inertia of the cross section of a liquid crystal elastomer thin plate ; The distance between the two magnets ; Heat transfer coefficient ;Light intensity .

[0163] In order to study the feedback effect of light intensity monitoring equipment for different light intensities, the dimensionless shrinkage coefficient is given , thickness of composite sheet , the distance between the two magnets , moment of inertia , when these parameters are fixed, the light intensity Gradually increase from 0.

[0164] When the light intensity When the light intensity is , the light drive structure cannot form a self-control state, the periodic working state of the light intensity monitoring device cannot be triggered, and the light source cannot produce periodic flashing. When the light drive structure can form a self-control state, the periodic working state of the light intensity monitoring device is triggered, and the light source produces periodic flashes along with the self-control process of the light drive structure. At the same time, it can be seen that: under the condition of triggering the periodic working state of the light intensity monitoring device, as the light intensity Increase the flashing frequency of the light source That is, different degrees of external disturbance will show different feedback effects on the light intensity monitoring device in this embodiment. The greater the disturbance, the faster the light source flickers. Therefore, the external light intensity condition can be judged according to the flickering state of the light source, such as Figure 11 shown.

[0165] Figure 11 The results are only considered when the parameters have been selected. If the parameters are not selected, the system parameters of the light intensity monitoring device can be adjusted according to the different light thresholds to be monitored, so as to be applicable to various scenarios with different monitoring requirements.

[0166] Example 4

[0167] This embodiment provides a toy design based on the third embodiment: a self-excited striking bell. The specific implementation is as follows:

[0168] The equipment for preparation and assembly can be selected from some of the equipment in Example 3. A metal bell component 7 is fixed inside the protective shell 1, and a threaded blind hole is opened just above the metal block 23 to connect a second lightweight insulating rod 6 with a thread at the lower end. Figure 12-13 , the protruding end of the second lightweight insulating rod 6 is consistent with the height of the metal bell 73.

[0169] In this embodiment, the metal bell component 7 is fixed on the right side inside the protective shell 1, the metal bell 73 is fixed on the second fixing plate 71, and the second fixing plate 71 is fixed to the protective shell 1 by the third flat head screw 72 and the fourth flat head screw 74.

[0170] The operating principle of this embodiment is as follows: The device is exposed to light. Based on the force criterion for the bouncing of metal block 23 in Example 2, light shines through light-transmitting aperture 12 in protective housing 1 onto liquid crystal elastomer sheet 242. When the light intensity reaches a certain level, metal block 23, like in Example 2, drives second lightweight insulating rod 6 to bob leftward within protective housing 1. At this point, liquid crystal elastomer sheet 242 leaves the illuminated area, gradually dissipating heat and cooling it, restoring the previous photothermal deformation. The composite sheet 24 then drives metal block 23 to bob rightward, causing second lightweight insulating rod 6 to strike metal bell 73 on the right side, producing a ringing sound. The liquid crystal elastomer sheet 242 then enters the illuminated area, repeating the above action, producing a continuous, periodic percussive sound.

[0171] Each embodiment in this specification is described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Reference can be made to the same or similar parts between the embodiments. For the above embodiments, since they are basically similar to the method embodiments, the description is relatively simple. For relevant parts, refer to the partial description of the method embodiments.

[0172] The above embodiments provide a detailed introduction to the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A self-control method for a self-excited burst light-driven structure, characterized in that: The method comprises the following steps: S1. Calculate the light-driven curvature of a liquid crystal elastomer sheet under uniform illumination ; S2, based on light-driven curvature Calculating the tensile force generated by a thin liquid crystal elastomer plate under photothermal actuation ; S3. Obtaining the contraction strain of the liquid crystal elastomer sheet under photothermal drive and temperature change the relationship between; S4, based on shrinkage strain and temperature change The relationship between the internal temperature of the liquid crystal elastomer sheet in the light area is obtained. Over time The equation of change is: ； And, the internal temperature of the liquid crystal elastomer sheet in the non-illuminated area Over time The equation of change is: ； Where, represents the extreme temperature difference of the liquid crystal elastomer sheet corresponding to the photothermal response; is the thermal relaxation time; S5, combine steps S1 and S4 to establish a method for adjusting the light and heat intensity. To change the critical control equation of the working state and realize the regulation of the autonomous jump process of the light-driven structure.

2. The self-control method according to claim 1, characterized in that: In step S1, it includes: S11. Calculate the torque generated by a thin liquid crystal elastomer plate under light , the calculation formula is: ； Where, is the thickness of the composite sheet; The non-uniform light-driven contraction strain of a liquid crystal elastomer sheet along the thickness direction under illumination; is the elastic modulus of the liquid crystal elastomer sheet; Indicates the thickness variable of the liquid crystal elastomer sheet in the integration process from arrive integral; S12. Define that the light irradiated on the liquid crystal elastomer sheet is uniform and obtain the light-driven curvature The expression is: ； S13, torque Substitute into step S12 to obtain the light-driven curvature of the liquid crystal elastomer sheet under uniform light ,Right now: ； Where, is the principal moment of inertia of the cross section of the liquid crystal elastomer thin plate.

3. The self-control method according to claim 1, characterized in that: In step S2, the tension The calculation formula is: ； Where, is the displacement of the free end of the composite plate; is the height of the liquid crystal elastomer sheet; is the elastic modulus of the liquid crystal elastomer sheet; is the principal moment of inertia of the cross section of the liquid crystal elastomer thin plate.

4. The self-control method according to claim 1, characterized in that: In step S3, the contraction strain and temperature change The relationship between them is: ； Where, is the shrinkage coefficient of the liquid crystal elastomer sheet.

5. The self-control method according to claim 1, characterized in that: In step S4, it includes: S41, according to the shrinkage strain and temperature change The relationship between the temperature change of the liquid crystal elastomer sheet at room temperature is obtained. The expression is: ； Where, is the absolute temperature of the liquid crystal elastomer sheet; is the ambient temperature at normal temperature; S42. Specific heat capacity of liquid crystal elastomer sheet obtained by measurement , heat transfer coefficient and the intensity of light and heat received ; S43, given thermal relaxation time , solve the temperature change of the liquid crystal elastomer sheet under light The expression is: ； S44: Based on step S43, the internal temperature of the liquid crystal elastomer sheet in the illumination area is obtained. Over time The equation of change, and the internal temperature in the non-illuminated area Over time The changing equation.

6. The self-control method according to claim 1, characterized in that: In step S5, the critical control equation is expressed as: ； Where, is the magnetic attraction force of the right magnet; is the magnetic attraction force of the left magnet; is the force of contraction of the liquid crystal elastomer sheet under light illumination; is the force of the liquid crystal elastomer sheet to recover in the absence of light; is the shrinkage coefficient of the liquid crystal elastomer sheet; is the distance between the right and left magnets; is the height of the liquid crystal elastomer sheet; is the elastic modulus of the liquid crystal elastomer sheet; is the principal moment of inertia of the cross section of the liquid crystal elastomer thin plate.

7. A light-driven structure, utilizing the self-control method according to any one of claims 1 to 6, characterized in that: The light-driven structure can form a continuous, periodic, and autonomous hopping process under light conditions, and the hopping frequency can be changed by adjusting the parameters of the light-driven structure. The light-driven structure comprises a light-transmitting hole (12) provided on the protective shell (1), and a control component (2) provided in the protective shell (1); The control assembly (2) comprises a composite thin plate (24) with one end fixed inside the protective shell (1), and a left magnet (21) and a right magnet (22) detachably fixed to two sides of the interior of the protective shell (1), wherein a metal block (23) at the same height as the right magnet (22) is fixed to the free end of the composite thin plate (24); When the composite thin plate (24) is in an initial state without bending, the metal block (23) and the right magnet (22) are in contact and fixed by magnetic attraction force and are in a static equilibrium state. The composite thin plate (24) includes a liquid crystal elastomer thin plate (242) having photothermal response characteristics, and an inert layer (241) tightly bonded to the liquid crystal elastomer thin plate (242); When sufficiently strong external light passes through the light-transmitting hole (12) and irradiates the liquid crystal elastomer sheet (242), the composite sheet (24) undergoes photothermal deformation and bending in the illuminated area, pulling the metal block (23) away from the right magnet (22), and instantly jumps to the left side to contact the left magnet (21) and be fixed by magnetic attraction; At this time, the light is blocked by the curved inert layer (241) and the liquid crystal elastomer sheet (242) is placed in a non-illuminated area. The liquid crystal elastomer sheet (242) gradually dissipates heat in the non-illuminated area and cools down to recover the previous photothermal deformation. The elastic force generated drives the metal block (23) to jump toward the right magnet (22) and contact it again. The liquid crystal elastomer sheet (242) enters the illuminated area again to realize an autonomous reciprocating alternating jumping process.

8. The optical drive structure according to claim 7, wherein: The left magnet (21) and the right magnet (22) are both detachably mounted on the protective shell (1) via a fixing member (3). The fixing member (3) is adapted to left magnets (21) or right magnets (22) of different sizes and can be assembled, disassembled, and fixed.

9. A light intensity monitoring device, using the light drive structure according to claim 8, characterized in that: It is used to produce different feedback effects according to different degrees of external disturbance, so as to monitor or judge the external light intensity conditions; The light intensity monitoring device comprises a first fixing plate (51) fixed on the protective shell (1), and a first lightweight insulating rod (4) having one end fixed on the metal block (23); a light source (54) for controlling the on / off of a circuit via a normally open switch (59) is mounted on the first fixing plate (51); the normally open switch (59) is mounted in the protective shell (1) and corresponds to the free end of the first lightweight insulating rod (4); Under light conditions, the light-driven structure drives the first lightweight insulating rod (4) to bounce back and forth in the left and right directions within the protective shell (1). When the first lightweight insulating rod (4) hits the normally open switch (59), the switch closes to form a closed loop, causing the light source (54) to emit light.

10. The light intensity monitoring device according to claim 9, characterized in that: The light source (54) generates periodic flashes along with the self-controlled jump process of the light driving structure, and is used to monitor or judge the external light intensity condition.

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