Preparation and drive control method of sectional type variable stiffness hybrid antisymmetric bistable laminated plate

Abstract

The invention discloses a preparation and drive control method of a sectional type variable-stiffness hybrid antisymmetric bistable laminated plate, and the sectional type variable-stiffness hybrid antisymmetric bistable laminated plate is formed by laying cut carbon fiber prepreg and metal sheets and carrying out high-temperature curing. The problems that self-adaption and controllable driving cannot be combined in existing bistable state laminated plate driving control, and two driving temperatures between stable state configurations in thermal driving control cannot be regulated and controlled are solved. Therefore, the metal sheet and the carbon fiber prepreg which are subjected to tailoring design are introduced, the rigidity and curvature of a mixed layer in the laminated plate are improved, steady-state conversion can be achieved through different thermal drive control mechanisms by means of the edge effect of the laminated plate and the potential energy difference between steady-state configurations after design, and the stability of the laminated plate is improved. A novel driving control mechanism combining self-adaption and active control is achieved, and a stable state which is greatly different from an original configuration shape and does not need to be maintained by external force is obtained after cooling. Therefore, the method has a wider application prospect.

Description

Technical Field

[0001] The present invention belongs to the technical field of space structure material design, and relates to a design preparation and driving control method for a bistable composite laminate, specifically to a preparation and driving control method for a segmented variable-stiffness hybrid anti-symmetric bistable laminate. Background Art

[0002] In current engineering fields such as aerospace and renewable energy utilization, there are specific requirements for the mass, size, and driving control mechanisms of deformable structures, such as deployable solar sails, deployable antennas, foldable antennas, and self-folding solar panels. These structures have the advantages of high specific strength, high variability, low density, and easy driving control. Due to the uneven internal stress after the bistable laminate cools from the curing temperature to room temperature, it has two or more stable configurations, and the stable state does not require external force to maintain and can be realized through external energy input to achieve the stable state transition. Due to the advantages of low preparation cost, light weight, high strength, and fast transition speed, this structure has been widely used in advanced manufacturing fields such as aerospace, energy harvesting, and robotics.

[0003] Currently, there are various driving methods for carbon fiber-reinforced bistable composite structures, such as mechanical load driving control, intelligent material driving, and temperature field driving. However, each different driving method has its own advantages and disadvantages. For example, load driving requires external equipment to achieve the stable state transition; it is difficult to avoid the control of external equipment in the driving control of intelligent materials such as piezoelectric materials, shape memory alloys, and shape memory polymers; taking magnetic field driving as an example in energy field driving, although this method has the advantages of non-contact driving and rapid response, it is difficult to control the magnetic field strength and distribution. With the growing demand for new driving control methods that combine self-adaptation and active control in the aerospace and robotics fields, the existing driving control methods are difficult to meet such high-performance requirements. In addition, the existing thermal driving control methods cannot regulate the two driving temperatures between the stable configurations in thermal driving control, which greatly limits the application range of this structure. Summary of the Invention

[0004] In order to realize the method of combining self-adaptive driving and active control for the laminate in the background art, the present invention proposes a preparation and driving control method for a segmented variable-stiffness hybrid anti-symmetric bistable laminate. The purpose of the present invention is to adjust the stable configuration and mutation load of the laminate by changing the width of the hybrid layer and the thickness of the metal layer in the laminate. When the segmented variable-stiffness hybrid anti-symmetric bistable laminate is in the first stable state, by heating the hybrid area of the laminate, the edge effect can gradually become obvious and the stable state transition can occur; when the segmented variable-stiffness hybrid anti-symmetric bistable laminate is in the second stable state, by heating the entire laminate to eliminate the potential energy barrier between the stable states to achieve the stable state transition, and the potential energy difference between the stable states can be changed by changing the laminate parameter design.

[0005] The technical solution of the present invention is as follows: A preparation method of a segmented variable-stiffness hybrid anti-symmetric bistable laminate, comprising the following steps: S1: Cut one metal layer, n complete layers of carbon fiber prepreg, and n deformed layers of carbon fiber prepreg as required, a total of (2n + 1) layers, and lay them on a metal flat die according to preset laying requirements to obtain a material stack layer; where n is a positive integer; S2: After pressing the laid material stack layer, put it into an autoclave for heating and curing, and obtain a segmented variable-stiffness hybrid anti-symmetric bistable laminate in an initial shape after cooling, and it is in the first stable state; S3: Change the shape of the segmented variable-stiffness hybrid anti-symmetric bistable laminate in the initial shape through a certain driving and controlling method to obtain a second stable state without external force maintenance. The driving and controlling methods include external force load, thermal driving and control, etc.

[0006] Further, the shape of the complete layer of carbon fiber prepreg is a square structure, and the deformed layer of carbon fiber prepreg is obtained by cutting off two symmetric diagonal corners on the basis of the complete layer of carbon fiber prepreg. The shape of the metal layer is the same as that of the deformed layer of carbon fiber prepreg.

[0007] Further, the preset laying requirements are specifically as follows: The metal layer is located in the middle layer of the laminated structure. Carbon fiber prepreg complete layers are arranged on both sides of the metal layer, and deformed layers of carbon fiber prepreg are arranged on the outside of the carbon fiber prepreg complete layers, and so on. That is, on each side of the middle layer, there is an alternating laying method of carbon fiber prepreg complete layers and deformed layers of carbon fiber prepreg. The material on one side of the metal layer forms a first stack layer, and the material on the other side of the metal layer forms a second stack layer. The fiber direction angle of the carbon fiber prepreg in the first stack layer is 45°, and the fiber direction angle of the carbon fiber prepreg in the second stack layer is -45°. The two parts of the material are laid in an anti-symmetric manner, and the laying directions of the metal layer and the deformed layer of carbon fiber prepreg are kept consistent.

[0008] Further, due to the stacking of the deformed layer of carbon fiber prepreg and the metal layer, the local thickness in the middle of the laminate is greater than that of the remaining areas. The middle section with a larger thickness is called the hybrid layer. Take the length of the complete layer of carbon fiber prepreg as 2a, then the width L of the hybrid layer is always less than .

[0009] Further, the overall shape of the laminate is square, and the thickness of the metal layer is 0.01 mm - 0.2 mm; Further, the carbon fiber prepreg is one of T700 unidirectional carbon fiber epoxy resin prepreg, T800 unidirectional carbon fiber epoxy resin prepreg, and T700 unidirectional carbon fiber bismaleimide prepreg; the metal layer is one of iron sheet, copper sheet, zinc sheet, or aluminum sheet; the metal plate is one of iron plate, aluminum plate, or copper plate coated with high-temperature resistant cloth.

[0010] Further, in step S2, the temperature for high-temperature curing is 150°C - 180°C, and the curing time is 1.5 h - 3 h.

[0011] Further, by changing the width of the hybrid layer to adjust the variable stiffness ratio of the laminate, or by changing the thickness of the metal layer to adjust the proportion of the metal layer in the laminate, the steady-state characteristics of the laminate can be changed. The steady-state characteristics include steady-state curvature and critical load, where the steady-state curvature first increases and then decreases with the increase of the metal layer thickness and the hybrid layer width; the critical load increases with the increase of the metal layer thickness and the hybrid layer width.

[0012] The metal layer serves as the intermediate layer, and its thickness in the composite material, as well as the shape and size of the hybrid layer, are variables, thereby improving the flexibility of structural design.

[0013] Segmented (the setting of the hybrid layer and ensuring that the width L of the hybrid layer is always less than ) anti-symmetric laying is beneficial for the bistable structure to present the desired configuration and obtain ideal steady-state transition characteristics.

[0014] The shape of the metal layer is a polygon as shown in Figure 1 , and the thickness range of the metal sheet is 0.01 mm - 0.2 mm. The shape of the hybrid layer always remains the same as that of the metal layer.

[0015] Driving method for the segmented variable stiffness hybrid anti-symmetric bistable laminate: Refer to Figure 2 , and the specific driving method is as follows: At room temperature, heat the hybrid region in the segmented variable stiffness hybrid anti-symmetric bistable laminate in the first steady state, and use the non-uniform stress at the edge of the laminate to cause the steady-state transition of the laminate; heat the whole, apply electricity, or stimulate with infrared light to the segmented variable stiffness hybrid anti-symmetric bistable laminate in the second steady state, so that the laminate is heated to the critical transition temperature, and due to the potential energy difference between the two steady states, the laminate undergoes a steady-state transition.

[0016] During the process of the transition from the first stable state to the second stable state, by heating the local hybrid region, the thermal residual stress in the intermediate region decreases due to heat, thereby reducing the curvature of the hybrid region. At the same time, the edge effect at the diagonal of the laminate gradually increases. As the local heating temperature rises, the edge effect becomes more significant until the critical heating temperature is reached, and the laminate undergoes a stable state transition.

[0017] During the process of the transition from the second stable state to the first stable state, due to the presence of the hybrid variable stiffness layer, the strain energy of the second stable state is higher than that of the first stable state. By heating the laminate, the thermal residual stress decreases due to heat, and the strain energy also decreases accordingly. When the heating temperature rises to the critical temperature, the potential energy barrier between the stable states of the laminate disappears, and the structure changes from bistable to monostable, thus completing the stable state transition.

[0018] The present invention also proposes a method to increase the driving and controlling temperature for the transition from the first stable state to the second stable state while decreasing the driving and controlling temperature for the transition from the second stable state to the first stable state: by changing the thickness of the metal layer. When the thickness of the metal layer increases, the driving and controlling temperature for the transition from the first stable state to the second stable state also increases, while the driving and controlling temperature for the transition from the second stable state to the first stable state decreases.

[0019] The beneficial effects of the present invention are as follows: The present invention adopts a segmented variable stiffness hybrid antisymmetric bistable laminate. Through segmented design and the introduction of a metal layer, not only the mechanical properties of the material are improved, but also the stable state configuration of the ideal laminate can be obtained by changing parameters to meet the engineering requirements, and it has potential application prospects in the aerospace field (such as self-deployable sunshades). In terms of actuation, due to the segmented design of the laminate and the introduction of the hybrid variable stiffness layer, the edge effect of the laminate and the potential energy difference between the stable state configurations are caused, enabling the laminate to obtain active control and adaptive actuation under different thermal actuation mechanisms, and making this structure have broad application prospects in fields such as renewable energy harvesting (such as adaptive solar tracking structures) and soft robots (such as the actuation and control unit of a petal-like gripper). In addition, during the stable state transition of the segmented variable stiffness laminate from the second stable state to the first stable state, due to the relatively large potential energy difference between the stable state configurations caused by the laminate design, the laminate will release more energy during the transition process, generating a relatively large deformation force and causing the structure to bounce, which has broad application prospects in the field of jumping robots. Combining the above characteristics, it can not only be used for adaptive actuation and active control of deployable structures, but also has great potential in the fields of soft robots and energy harvesting, which is not possessed by the previously reported bistable laminates. Description of the Drawings

[0020] Figure 1 It is a schematic diagram of the ply stacking sequence and geometric parameters of the segmented variable stiffness hybrid antisymmetric laminate according to the embodiment of the present invention; Figure 2Schematic diagram of the thermal drive and control mechanism of the segmented variable-stiffness hybrid antisymmetric laminated plate according to the embodiment of the present invention; Figure 3 Schematic diagram (I) of the drive and control experimental platform for the segmented variable-stiffness hybrid antisymmetric laminated plate according to the embodiment of the present invention; Figure 4 Schematic diagram (II) of the drive and control experimental platform for the segmented variable-stiffness hybrid antisymmetric laminated plate according to the embodiment of the present invention; Figure 5 Schematic diagram of the thermal drive (from the first steady state to the second steady state) of the segmented variable-stiffness hybrid antisymmetric laminated plate according to the embodiment of the present invention; Figure 6 Schematic diagram of the thermal drive (from the second steady state to the first steady state) of the segmented variable-stiffness hybrid antisymmetric laminated plate according to the embodiment of the present invention; Figure 7 Steady-state configuration measurement experimental platform for the segmented variable-stiffness hybrid antisymmetric laminated plate according to the embodiment of the present invention. Detailed implementation manners

[0021] In order to describe the invention purpose, invention advantages and technical solutions of the present invention more clearly and clearly, the present invention will be described in detail below in combination with the accompanying drawings and implementation methods. However, it should be understood that the implementation methods described below are only used to explain the present invention and are not limited to the present invention. The present invention will be described in detail below. Through these detailed descriptions, those skilled in the art can fully understand the present invention. As Figure 3 shown, based on the research on the drive and control characteristics of the segmented variable-stiffness hybrid antisymmetric laminated plate of the present invention, a drive and control experimental platform (from the first steady state to the second steady state) is built by using a temperature measuring instrument, a patch-type temperature sensor, an electric heating sheet, a support and a DC power supply. The principle is to adhere the polyimide electric heating sheet on the hybrid layer area of the laminated plate, energize the electric heating sheet on the hybrid layer area of the laminated plate through the DC power supply to achieve the purpose of local area heating, and use the patch-type temperature sensor to detect the temperature of the laminated plate in real time to study its thermal drive and control steady-state transition characteristics.

[0022] As Figure 4 shown, based on the research on the drive and control characteristics of the segmented variable-stiffness hybrid antisymmetric laminated plate of the present invention, a drive and control experimental platform (from the second steady state to the first steady state) is built by using a temperature measuring instrument, a patch-type temperature sensor, an infrared heating instrument, a support and an adjustable lifting platform. The principle is to heat the laminated plate as a whole through the infrared heating instrument, change the temperature of the specimen and the heat source through the lifting platform, and use the patch-type temperature sensor to detect the temperature of the laminated plate in real time to study its thermal drive and control steady-state transition characteristics.

[0023] As Figure 7As shown, based on the research on the steady-state characteristics of the segmented variable-stiffness hybrid antisymmetric laminated plate of the present invention, a steady-state configuration test platform was built using a handheld 3D scanner and a host computer. The sample was scanned by the 3D scanner, and the scanned model was post-processed by post-processing software to study its steady-state configuration.

[0024] Based on the research on the steady-state characteristics of the segmented variable-stiffness hybrid antisymmetric laminated plate of the present invention, a steady-state transition load test platform was built through a tensile and compression testing machine (INSRTON LEGEND-2345), using a force sensor, a indenter, a fixture and a host computer. The specimen was fixed by the fixture, and the specimen was loaded by a universal tensile testing machine to study its steady-state transition characteristics.

[0025] The preparation method of the segmented variable-stiffness hybrid antisymmetric bistable laminated plate in this embodiment includes the following steps: S1: Use a cricut paper cutter to cut the carbon fiber reinforced composite prepreg and the metal layer. A total of 5 layers are cut, including one metal layer, 2 complete layers of carbon fiber prepreg and 2 deformed layers of carbon fiber prepreg; the cut prepregs and the metal layer are laid on a metal flat die according to the laying requirements (such as Figure 1 ). S2: Put the material stack layer into an autoclave for heating and curing. After cooling, a segmented variable-stiffness hybrid antisymmetric bistable laminated plate in the initial shape is obtained and is in the first steady state.

[0026] S3: Change the shape of the segmented variable-stiffness hybrid antisymmetric bistable laminated plate in the initial shape by an external force to obtain a second steady state that does not require external force to maintain.

[0027] In this embodiment, the metal layer is a polygon as shown in Figure 1 . The material is copper, the thickness is 0.1 mm, and the width is 50 mm; the shape of the hybrid layer always remains the same as that of the metal layer, and its width ranges from 20 mm to 80 mm. The material of the carbon fiber prepreg is T700 unidirectional carbon fiber epoxy resin-based prepreg, and the shapes are square (complete layer of carbon fiber prepreg) and polygon (deformed layer of carbon fiber prepreg) with the same shape as the metal layer. The thickness is 0.1 mm, and the fiber directions are arranged in sequence as -45°, -45°, copper, 45° and 45°. The number of layers is 5; the metal flat plate is an aluminum plate wrapped with high-temperature resistant cloth; the high-temperature curing temperature is 180 °C and the curing time is 3 h. The overall laminated plate prepared in this embodiment is a square with a side length of 100 mm, the thickness of the metal layer is 0.01 mm - 0.2 mm, and the width of the hybrid layer is 20 mm - 80 mm.

[0028] Specific preparation method of the segmented variable-stiffness hybrid anti-symmetric bistable laminate in step S1: Number of layers laid: A total of five layers, including four carbon fiber prepreg material layers (wherein there are 2 complete carbon fiber prepreg layers and 2 deformed carbon fiber prepreg layers) and one metal layer; Laying angle: The angles of the first and second carbon fiber prepregs are 45°, and the angles of the fourth and fifth carbon fiber prepregs are -45°; The metal layer is the middle layer of the laminated structure and is aligned with the laying directions of the first and fifth carbon fiber prepregs; Laying sequence: Ensure that the first layer, the second layer, the middle metal layer, the fourth layer, and the fifth layer are laid in sequence.

[0029] For the segmented variable-stiffness hybrid anti-symmetric bistable laminate prepared in the embodiment, the driving and controlling method for its first stable state to undergo a stable state transition to the second stable state is to heat the hybrid region through a polyimide electric heating film, making the edge effect of the laminate gradually obvious until the stable state transition temperature is reached. At this time, after cooling, the stable state configuration of the laminate is the second stable state and no external force is required to maintain it, as Figure 5 shown. In addition, it can also be achieved by the method of external force loading.

[0030] For the segmented variable-stiffness hybrid anti-symmetric bistable laminate prepared in the embodiment, the driving and controlling method for its second stable state to undergo a stable state transition to the first stable state is to heat the specimen through an infrared heating lamp. The curvature of the laminate decreases, and its potential energy also decreases accordingly until the stable state transition temperature is reached. The potential energy barrier between the stable state configurations is eliminated and a stable state transition occurs. At this time, after cooling, the stable state configuration of the laminate is the first stable state and no external force is required to maintain it. The transition process is as Figure 6 shown. In addition, it can also be achieved by the method of external force loading.

[0031] In addition, since the driving and controlling temperatures between the two stable states of the conventional thermally driven bistable laminate are relatively close, this greatly reduces the designability of the laminate. Therefore, this method also proposes a method to increase the driving and controlling temperature from the first stable state to the second stable state while decreasing the driving and controlling temperature from the second stable state to the first stable state. This method is: When changing the thickness of the metal layer, when the thickness of the metal layer increases, the driving and controlling temperature from the first stable state to the second stable state also increases, while the driving and controlling temperature from the second stable state to the first stable state decreases.

[0032] Six groups of bistable carbon fiber composite laminates, namely 1, 2, 3, 4, 5, and 6, are prepared according to the preparation method of the above embodiment. The thicknesses of the metal layers in the six groups of 1, 2, 3, 4, 5, and 6 are 0.02 mm, 0.05 mm, 0.08 mm, 0.1 mm, 0.15 mm, and 0.2 mm respectively. After preparation, the laminates are driven and controlled through the above-mentioned thermal driving and controlling platform, and the required driving and controlling temperature values are measured through temperature sensors.

[0033] The test results show that: 1. For the six groups of 1, 2, 3, 4, 5, and 6, the driving and controlling temperatures for the transformation from the first stable state to the second stable state increase in sequence; correspondingly, the driving and controlling temperatures for the transformation from the second stable state to the first stable state decrease in sequence. During the transformation from the first stable state to the second stable state, the driving and controlling temperature increases with the increase in the thickness of the metal layer. This is because as the thickness of the metal layer increases, the stiffness of the hybrid variable stiffness layer enhances, and the influence of the edge effect caused by local heating on it weakens, resulting in an increase in the required driving and controlling temperature. While during the transformation from the second stable state to the first stable state, the driving and controlling temperature decreases with the increase in the thickness of the metal layer. This is because the coefficient of thermal expansion of the metal layer is higher than that of the carbon fiber composite material. As the thickness of the metal layer increases, the overall coefficient of thermal expansion of the hybrid variable stiffness layer further increases. When the temperature rises, the metal layer will generate strain faster, prompting the laminate to undergo a stable state transformation at a lower temperature.

[0034] Eight groups of bistable carbon fiber composite laminates of 1, 2, 3, 4, 5, 6, 7, and 8 were prepared according to the preparation method of the above embodiment. Among them, the widths of the hybrid layers of groups 1 to 4 were set to 20 mm, 40 mm, 60 mm, and 80 mm respectively; the thicknesses of the metal layers of groups 5 to 8 were 0.05 mm, 0.1 mm, 0.15 mm, and 0.2 mm respectively. After preparation, the stable configurations and transformation loads of each group of laminates were measured using a stable configuration test platform and a stable state transformation load test platform. The test results show that: for groups 1 to 8, the first stable state principal curvature first increases and then decreases with the increase in the width of the hybrid layer and the thickness of the metal layer; at the same time, the transformation loads of groups 1 to 8 increase significantly with the increase in the width of the hybrid layer and the increase in the thickness of the metal layer.

[0035] It can be seen that the segmented variable stiffness hybrid antisymmetric bistable laminate of the present invention can combine active control and adaptive control, can utilize different driving and controlling mechanisms to achieve the transformation between different stable states of the laminate, and can adjust the driving and controlling temperature between stable states by changing the thickness of the metal layer in the laminate. The above functional adjustments make the laminate more designable, the driving and controlling mechanism more perfect, more intelligent, and have a broader application prospect.

[0036] It should be noted that the first stable state described in the present invention is the state when the variable stiffness hybrid layer is in x 2 the shape when bending; the second stable state is the state when the variable stiffness hybrid layer is in x 1 the shape when bending, referring to the coordinates in Figure 1 the figure.

[0037] The above detailed description of the present invention is only a preferred embodiment and is not used to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing a segmented variable stiffness hybrid antisymmetric bistable laminate, characterized in that: The steps include: S1: Cut a metal layer, n carbon fiber prepreg complete layers and n carbon fiber prepreg deformed layers as required, a total of (2n+1) layers, and lay them on a metal flat plate mold according to preset laying requirements to obtain a material stacking layer; wherein n is a positive integer; S2: After the laid material stacking layers are pressed, they are placed in an autoclave for heating and curing, and after cooling, a segmented variable stiffness hybrid antisymmetric bistable laminate with an initial shape is obtained, which is in a first stable state; S3: The shape of the initial shape of the segmented variable stiffness hybrid antisymmetric bistable laminate is changed by a certain driving control method to obtain a second stable state that does not require external force to maintain.

2. The method for preparing a segmented variable stiffness hybrid antisymmetric bistable laminate according to claim 1, characterized in that: The shape of the complete carbon fiber prepreg layer is a square structure, the deformed carbon fiber prepreg layer is obtained by cutting off two symmetrical diagonal corners on the basis of the complete carbon fiber prepreg layer, and the shape of the metal layer is consistent with the shape of the deformed carbon fiber prepreg layer.

3. The method for preparing a segmented variable stiffness hybrid antisymmetric bistable laminate according to claim 2, characterized in that: The preset laying requirements are specifically as follows: the metal layer is located in the middle layer of the laminated structure, carbon fiber prepreg complete layers are arranged on both sides of the metal layer, and carbon fiber prepreg deformation layers are arranged on the outer sides of the carbon fiber prepreg complete layers, and so on, that is, each side of the middle layer is a laying method in which carbon fiber prepreg complete layers and carbon fiber prepreg deformation layers are alternately arranged, one side material of the metal layer constitutes the first stacking layer, and the other side material of the metal layer constitutes the second stacking layer, the fiber direction angle of the carbon fiber prepreg in the first stacking layer is 45°, and the fiber direction angle of the carbon fiber prepreg in the second stacking layer is -45°, and they are laid in an anti-symmetrical manner, and the laying directions of the metal layer and the carbon fiber prepreg deformation layer are consistent.

4. The method for preparing a segmented variable stiffness hybrid antisymmetric bistable laminate according to claim 3, characterized in that: The laminate has a local thickness in the middle that is greater than the rest of the area due to the stacking of the deformed carbon fiber prepreg layer and the metal layer. The middle section with a larger thickness is called a hybrid layer. The length of the complete carbon fiber prepreg layer is 2a, and the width L of the hybrid layer is always set to be less than .

5. The method for preparing a segmented variable stiffness hybrid antisymmetric bistable laminate according to claim 4, characterized in that: The overall shape of the laminate is a square, and the thickness of the metal layer is 0.01 mm-0.2 mm.

6. The method for preparing a segmented variable stiffness hybrid antisymmetric bistable laminate according to claim 4, characterized in that: The carbon fiber prepreg is one of T700 unidirectional carbon fiber epoxy resin-based prepreg, T800 unidirectional carbon fiber epoxy resin-based prepreg, and T700 unidirectional carbon fiber bismaleamide-based prepreg; the metal layer is one of iron sheet, copper sheet, zinc sheet or aluminum sheet; the metal flat plate is one of iron sheet, aluminum sheet or copper sheet covered with high temperature resistant cloth.

7. The method for preparing a segmented variable stiffness hybrid antisymmetric bistable laminate according to claim 4, characterized in that: The high temperature curing temperature in step S2 is 150° C.-180° C., and the curing time is 1.5 h-3 h.

8. The method for preparing a segmented variable stiffness hybrid antisymmetric bistable laminate according to claim 4, characterized in that: The steady-state characteristics of the laminate can be changed by changing the width of the hybrid layer to adjust the variable stiffness ratio of the laminate, or by changing the thickness of the metal layer to adjust the proportion of the metal layer in the laminate. The steady-state characteristics include steady-state curvature and critical load. The steady-state curvature increases first and then decreases with the increase of the thickness of the metal layer and the width of the hybrid layer. The critical load increases with the thickness of the metal layer and the width of the hybrid layer.

9. A driving and controlling method for a segmented variable stiffness hybrid antisymmetric bistable laminate prepared by the preparation method according to any one of claims 4 to 8, characterized in that: At room temperature, the mixed layer area in the segmented variable stiffness hybrid antisymmetric bistable laminate in the first stable state is heated, and the uneven stress at the edge of the laminate is used to make the laminate undergo a stable state transition; the segmented variable stiffness hybrid antisymmetric bistable laminate in the second stable state is heated as a whole, powered on or stimulated by infrared light, so that the laminate is heated to the critical transition temperature, and due to the potential energy difference between the two stable states, the laminate undergoes a stable state transition.

10. The driving and controlling method of the segmented variable stiffness hybrid antisymmetric bistable laminate according to claim 9, characterized in that: The thickness of the metal layer is changed. When the thickness of the metal layer increases, the driving temperature for the transition from the first stable state to the second stable state also increases, while the driving temperature for the transition from the second stable state to the first stable state decreases.

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