Bionic wave type variable stiffness ocean current power generation device

Abstract

This invention discloses a biomimetic wave-type variable stiffness ocean current power generation device, comprising a zero-buoyancy front blunt body, a high-elasticity spring, a fixed component body, a flexible thin film substrate, a piezoelectric generator, and several stiffness patches with different stiffnesses. The piezoelectric generator is disposed in an intermediate layer between the flexible thin film substrates. The stiffness patches are symmetrically arranged on both sides of the flexible thin film substrate, and each stiffness patch is non-uniformly arranged along the length of the flexible thin film substrate to form a non-uniform flexible variable stiffness configuration. One end of the piezoelectric generator is connected to the zero-buoyancy front blunt body. The high-elasticity spring is fixedly connected to the zero-buoyancy front blunt body through a mounting hole structure, and both ends of the high-elasticity spring are respectively connected to the fixed component body for installation on a riverbed or seabed base. This invention solves the technical problems of existing structures, such as high starting flow velocity, limited vibration amplitude, stress concentration that easily damages the piezoelectric element, and low energy harvesting efficiency and short service life due to the lack of stiffness control design.

Description

Technical Field

[0001] This invention relates to the field of marine micro-nano energy harvesting technology, and in particular to a biomimetic wave-type variable stiffness ocean current power generation device. Background Technology

[0002] In key areas such as deep-sea resource exploration, marine environmental early warning, and marine observation, the three-dimensional marine observation network serves as a core component. However, since the energy supply systems of deep-sea observation nodes are typically deployed in deep-sea areas and need to support the long-term stable operation of the network, the energy supply system remains the biggest bottleneck for these nodes. These nodes are usually equipped with sensors, communication equipment, and data processing units, requiring stable power support. Traditional power supply methods, such as battery and external cable power supply, face numerous challenges in terms of energy and power density, cycle stability, flexibility, and biodegradability. While batteries provide convenient short-term power, they require frequent replacement, have high maintenance costs, and pose a risk of environmental pollution. External cable power supply, while enabling continuous power supply, requires complex underwater cabling and is susceptible to environmental factors such as high pressure, low temperature, and seawater corrosion.

[0003] Piezoelectric power generation technology, with its advantages of simple structure, direct energy conversion, and adaptability to low-frequency mechanical energy harvesting, has become an important technological direction in the field of fluid energy harvesting. Flexible piezoelectric thin films, due to their small size, high flexibility, and adaptability to complex fluid environments, are widely used for energy harvesting from low-velocity fluids such as ocean currents, river currents, and industrial pipeline fluids. They provide self-powered support for various low-power monitoring sensors and wireless transmission modules, solving the problems of high maintenance costs and limited wiring of traditional battery-powered systems. However, existing flexible piezoelectric power generation devices based on flow-induced vibration generally suffer from the following technical bottleneck: high starting flow velocity. Traditional flexible piezoelectric structures typically employ a cantilever beam design with uniform stiffness. The critical flow velocity required to initiate flow-induced vibration under fluid action is relatively high. Low-velocity fluid environments make it difficult to generate effective vibration, resulting in weak vibration amplitude and an inability to effectively capture energy, thus hindering the effective excitation of piezoelectric elements to output electrical energy. Furthermore, ocean currents and river currents in natural environments are mostly in a low-velocity state, limiting the applicability of such devices.

[0004] Therefore, there is an urgent need to propose a biomimetic wave-type variable stiffness ocean current power generation device. Through the design of a non-uniform stiffness configuration, it can achieve the dual effects of low start-up flow velocity and high amplitude flow-induced vibration, while solving the stress concentration problem, improving energy collection efficiency and structural service life. This has become a technical problem that urgently needs to be solved in the field of fluid micro-nano energy collection technology. Summary of the Invention

[0005] This invention provides a biomimetic wave-type variable stiffness ocean current power generation device to overcome the above-mentioned technical problems.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows: A biomimetic wave-type variable stiffness ocean current power generation device includes a front-mounted floating vibration component, a flexible thin film substrate, a piezoelectric power generation sheet, and several stiffness patches with different stiffnesses. The pre-floating vibration assembly includes a zero-buoyancy pre-floating blunt body, a high-elasticity spring, and a fixed component body. The flexible thin film substrate includes a first flexible thin film structure and a second flexible thin film structure arranged symmetrically; the piezoelectric generator is disposed in the intermediate layer between the first flexible thin film structure and the second flexible thin film structure to form an integrated flexible power generation thin film body, and the piezoelectric generator is located at one end of the flexible thin film substrate. The stiffness patches are symmetrically arranged on both sides of the flexible power generation film body, and each stiffness patch is non-uniformly arranged along the length direction of the flexible power generation film body to form a non-uniform flexible variable stiffness configuration. In the non-uniform flexible variable stiffness configuration, one end of the piezoelectric generator is connected to the zero buoyancy front blunt body; the two ends of the zero buoyancy front blunt body are symmetrically provided with mounting hole structures, and the high elasticity spring is fixedly connected to the zero buoyancy front blunt body through the mounting hole structure; the two ends of the high elasticity spring are respectively connected to the fixed parts body for installation on the riverbed or seabed base. The piezoelectric generator is used to output electrical energy when it bends under external force; The external forces include the flow-induced vibrations generated by the flexible film substrate and stiffness patch acting on the piezoelectric generator when the water flow directly impacts the non-uniform flexible variable stiffness configuration, and the vortex-induced oscillations generated by the water flow impact on the non-uniform flexible variable stiffness configuration when the water flow impacts the front-mounted floating vibration component.

[0007] Furthermore, the zero-buoyancy front blunt body is a cylindrical structure with a hollow cavity formed by a first front blunt body component and a second front blunt body component arranged symmetrically.

[0008] Furthermore, the piezoelectric generator is made of a piezoelectric polymer PVDF film.

[0009] Furthermore, the materials of the flexible film substrate include, but are not limited to, polyimide and polydimethylsiloxane.

[0010] Furthermore, the fixed part body is provided with conductive terminals for connecting to external energy storage circuits or electrical equipment, the cylindrical structure is provided with lead wire through holes, the electrode leads at the end of the piezoelectric generator are connected to the conductive terminals through the lead wire through holes and then welded, and coated with a waterproof and anti-corrosion protective layer.

[0011] Furthermore, the thickness of each stiffness patch is 0.05-0.8 mm, and the total attachment area of ​​any stiffness patch accounts for 20%-30% of the surface area of ​​one side of the flexible film substrate.

[0012] Furthermore, a flexible adhesive layer is provided, through which the rigid patch is fixedly connected to the outer surface of the flexible film substrate.

[0013] Beneficial Effects: This invention provides a biomimetic wave-type variable stiffness ocean current power generation device. By mimicking the non-uniform stiffness distribution characteristics of aquatic organisms and by periodically setting stiffness patches with non-uniform stiffness variations along the length of the flexible film substrate surface, it achieves precise control over the overall stiffness of the flexible structure. Compared with the traditional uniform stiffness cantilever beam structure design, it can induce significant flow-induced vibrations at lower flow velocities, significantly reducing the start-up flow velocity threshold. Through the design of the non-uniform stiffness configuration and the pre-floating vibration component, this invention can generate effective vibrations in low-flow-velocity fluid environments to achieve effective energy capture. The non-uniform stiffness distribution, driven by the zero-buoyancy pre-floating blunt body, enables the flexible film substrate to generate vibration modes with larger amplitudes in the flow field, enhancing fluid-structure interaction efficiency and thus significantly improving the energy conversion efficiency of the piezoelectric power generation unit. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the structure of the biomimetic wave-type variable stiffness ocean current power generation device of the present invention; Figure 2 This is an exploded view of the flexible power-generating thin-film body with variable stiffness patches in this embodiment. Figure 3 This is a schematic diagram showing the connection between the flexible power generation film body and the zero-buoyancy front blunt body in this embodiment.

[0016] In the figure: 1. Flexible film substrate; 11. First flexible film structure; 12. Second flexible film structure; 2. Piezoelectric generator; 3. Stiffness patch; 4. Zero buoyancy front blunt body; 41. First front blunt body component; 42. Second front blunt body component; 5. High elasticity spring; 6. Fixing part body; 7. Mounting hole structure; 8. Hexagonal bolt reinforcement hole. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] This embodiment provides a biomimetic wave-type variable stiffness ocean current power generation device, including a front-mounted floating vibration component, a flexible thin film substrate 1, a piezoelectric power generation sheet 2, and several stiffness patches 3 with different stiffnesses; the front-mounted floating vibration component includes a zero-buoyancy front-mounted blunt body 4, a high-elasticity spring 5, and a fixed part body 6; the zero-buoyancy front-mounted blunt body 4 is a cylindrical structure with a hollow cavity formed by a first front-mounted blunt body component 41 and a second front-mounted blunt body component 42 arranged symmetrically; The flexible thin film substrate 1 includes a first flexible thin film structure 11 and a second flexible thin film structure 12 arranged symmetrically; the piezoelectric generator 2 is disposed in the intermediate interlayer between the first flexible thin film structure 11 and the second flexible thin film structure 12, forming an integrated flexible power generation thin film body, and the piezoelectric generator 2 is located at one end of the flexible thin film substrate 1. The stiffness patches 3 are symmetrically arranged on both sides of the flexible power generation film body, and each stiffness patch 3 is non-uniformly arranged along the length direction of the flexible power generation film body to form a non-uniform flexible variable stiffness configuration. The stiffness patches 3 are attached to the surface of the flexible power generation film substrate according to the non-uniform stiffness distribution law of aquatic organism bodies. The non-uniform flexible variable stiffness configuration can have low start-up flow velocity characteristics under the action of fluid and can generate a high amplitude flow-induced vibration response, realizing the conversion of flow-induced vibration mechanical energy into electrical energy. In the non-uniform flexible variable stiffness configuration, one end of the piezoelectric generator 2 is connected to the zero-buoyancy front blunt body 4; the two ends of the zero-buoyancy front blunt body 4 are symmetrically provided with mounting hole structures 7, and the high-elasticity spring 5 is fixedly connected to the zero-buoyancy front blunt body 4 through the mounting hole structures 7. The two ends of the high-elasticity spring 5 are respectively connected to the fixed part body 6 for installation on the riverbed or seabed base; in addition, the device in this embodiment is waterproofed and protected against corrosion based on waterproof and anti-corrosion protection technology; the zero-buoyancy front blunt body has equal weight and buoyancy, and the equality of weight and buoyancy allows it to be in a balanced state underwater; The piezoelectric generator 2 is used to output electrical energy when it bends under external force; The external forces include the flow-induced vibrations generated by the flexible film substrate 1 and the stiffness patch 3 on the piezoelectric generator 2 when the water flow directly impacts the non-uniform flexible variable stiffness configuration, and the vortex-induced oscillations generated by the water flow impact on the non-uniform flexible variable stiffness configuration when the water flow impacts the front floating vibration component.

[0019] In this embodiment, one end of the flexible power generation film body is connected to the zero-buoyancy front blunt body 4 via a fixed component 6 and a high-elasticity spring 5, forming a coupled vibration system of "zero-buoyancy front blunt body 4 - spring - flexible film". The device described in this embodiment is based on the non-uniform stiffness distribution characteristics of biomimetic aquatic organism bodies. Variable stiffness patches 3 with non-uniform stiffness are spaced along the length direction on the surface of the flexible film substrate, achieving fine control of the overall stiffness of the flexible structure. Compared with the traditional uniform stiffness cantilever beam structure design, it can induce significant flow-induced vibration at lower flow velocities, significantly reducing the starting flow velocity threshold. At the same time, the non-uniform stiffness distribution, driven by the zero-buoyancy front blunt body 4, enables the flexible film substrate to generate a larger amplitude vibration mode in the flow field, enhancing the fluid-structure coupling efficiency and thus greatly improving the energy conversion efficiency of the piezoelectric power generation unit. The device described in this embodiment has a simple structure, requires no complex transmission mechanism, and is highly adaptable. It can be widely used in micro-energy harvesting in fields such as marine, water conservancy, and industrial automation, providing continuous and stable self-powered support for various low-power electronic devices such as marine monitoring sensors, hydrological monitoring equipment, and industrial pipeline monitoring modules. It is particularly suitable for fluid environments with low flow rates and large flow rate fluctuations, effectively solving the problems of high maintenance costs and limited wiring associated with traditional power supply methods. It has good engineering application value and market prospects.

[0020] In a specific embodiment, the piezoelectric generator 2 is made of a piezoelectric polymer PVDF film, which is sandwiched between two layers of flexible film substrate 1. The PVDF film has a thickness of 0.1 mm and is coated with silver paste electrodes. Electrode leads are led out from the end of the film substrate and welded to the conductive terminals on the fixed column frame part, i.e., the fixed part body 6. The piezoelectric polymer PVDF film is fixed to the interlayer of the flexible film substrate 1 by adhesive bonding to form a piezoelectric generator unit. When the flexible film substrate 1 is bent and deformed, the piezoelectric polymer PVDF film generates charges due to the piezoelectric effect, and leads out wires through the surface electrodes to the energy storage circuit.

[0021] In a specific embodiment, the material of the flexible film substrate 1 includes, but is not limited to, polyimide and polydimethylsiloxane. In this embodiment, the flexible film substrate 1 is made of polymeric materials with good elasticity and water resistance, such as polyimide and polydimethylsiloxane, and has an overall elongated sheet structure with an effective vibration area length of 160 mm and a width of 50 mm.

[0022] In a specific embodiment, the fixed component 6 is provided with conductive terminals for connecting to external energy storage circuits or electrical equipment. The cylindrical structure has lead wire exit holes. The electrode leads at the end of the piezoelectric generator 2 are connected to the conductive terminals through the lead wire exit holes and then welded, and coated with a waterproof and anti-corrosion protective layer. Furthermore, buffer pads are provided between the piezoelectric generator 2 and the first flexible thin film structure 11 and the second flexible thin film structure 12. The buffer pads are made of flexible insulating material, which can buffer the stress impact on the piezoelectric generator 2 during flow-induced vibration, preventing the piezoelectric generator 2 from breaking due to frequent vibration or excessive local stress, while ensuring the insulation of the piezoelectric generator 2 and avoiding electrode short circuits.

[0023] In a specific embodiment, the zero-buoyancy front blunt body 4 can generate vortex-induced oscillations under the impact of water flow. The zero-buoyancy front blunt body 4 is a corrosion-resistant high-polymer rigid material. Driven by the high-elasticity spring 5 on the side, it can reduce the starting flow rate of the film and at the same time improve the flow-induced vibration of the film.

[0024] In a specific embodiment, the stiffness patch 3 includes three high-stiffness patch segments, three low-stiffness patch segments, and a stiffness transition patch segment. The high-stiffness patch segments are carbon fiber reinforced polyimide with a stiffness of approximately 1200 MPa and a length accounting for 20% of the effective vibration area. The stiffness transition patch segments and the low-stiffness patch segments are distributed in a gradient continuous manner on the outer surface of the flexible film substrate 1. For example, the free end of the flexible film substrate 1 is a stiffness transition patch segment / low-stiffness patch segment with a stiffness of approximately 200 MPa and a length accounting for 20%-30% of the effective vibration area. This simulates the gradual change in stiffness from the end to the middle of an aquatic organism's body, making the composite flexible power generation film body form a non-uniform stiffness distribution structure from the edge to the center, consisting of high stiffness, gradual stiffness, and low stiffness. This reduces the critical starting flow velocity for flow-induced vibration, increases the vibration amplitude, and simultaneously allows the vibration stress to be evenly distributed on the film surface, avoiding local stress concentration. The thickness of each stiffness patch 3 is 0.05-0.8 mm, and the total attachment area of ​​any one stiffness patch 3 accounts for 20%-30% of the surface area of ​​one side of the flexible thin film substrate 1. The attachment area of ​​the stiffness patch 3 is the effective vibration area of ​​the flexible thin film substrate 1, and the edge of the stiffness patch 3 is left with a preset distance from the edge of the flexible thin film substrate 1 to avoid the rigid constraint of the flexible thin film substrate 1 corresponding to the fixed frame, which would affect the control effect of the stiffness patch 3 on the stiffness distribution of the film. This ensures the stiffness control effect while avoiding the overall decrease in flexibility and vibration obstruction of the power generation film due to too many stiffness patches 3. Furthermore, in this embodiment, multiple stiffness patches 3 are spaced apart along the length of the flexible film substrate 1 on the upper and lower surfaces of the substrate. The stiffness patches 3 are made of composite materials, such as rigid plastic sheets adhered to an elastic rubber base layer. By adjusting the thickness, area, or distribution density of the rigid material in each patch, sufficient root support can be provided while reducing the starting flow velocity, allowing the film to generate greater amplitude flow-induced vibrations under low-velocity water flow excitation, thereby improving the conversion efficiency of mechanical energy to electrical energy. This non-uniform stiffness configuration, biomimetic to the torso of aquatic plants or fish, enables the film to generate significant flow-induced vibrations in water flows with velocities as low as 0.2 m / s, and the vibration amplitude is much greater than that of a uniform stiffness film.

[0025] In a specific embodiment, a flexible adhesive layer is also provided, and the stiffness patch 3 is fixedly connected to the outer surface of the flexible thin film substrate 1 through the flexible adhesive layer. The flexible adhesive layer has good elastic deformation capability and can undergo flow-induced vibration synchronously with the flexible thin film substrate 1 without affecting the vibration characteristics of the composite power generation thin film body, while ensuring the firmness of the variable stiffness patch 3 and preventing the patch from falling off under fluid impact.

[0026] To further enhance power generation efficiency, this embodiment includes a zero-buoyancy front blunt body 4 vibration coupling mechanism, i.e., a front-floating vibration assembly, installed in front of the flexible thin film substrate 1 in the upstream direction. The fixed end of the flexible thin film substrate 1 is connected to the fixed column frame, i.e., the fixed component body 6, via hexagonal bolt reinforcement holes 8. The fixed column frame component, i.e., the fixed component body 6, is a rigid frame used to install the entire device on a base on a riverbed or seabed. The zero-buoyancy front blunt body 4 is a cylindrical hollow structure with a diameter of 40mm and a height of 180mm. It has pre-drilled mounting holes 4 and spring mounting holes 5 inside, and its surface is treated with an anti-corrosion coating to adapt to marine water environments. The side of the zero-buoyancy front blunt body 4 is connected to a high-elasticity spring 5 via spring mounting holes 5, and the other end of the high-elasticity spring 5 is fixed to the fixed column frame component, i.e., the fixed component body 6. Among them, the high-elasticity spring 5 is made of stainless steel, with a spring wire diameter of 2mm and an effective number of 30 turns. One end is connected to the zero-buoyancy front blunt body 4 through the spring mounting hole 5, and the other end is connected to the external fixed base. The zero-buoyancy front blunt body 4 can generate reciprocating vibration under the impact of water flow.

[0027] When impacted by water flow, the device described in this embodiment exhibits a dual vibration power generation effect: The first effect is that when water flows directly impacts the device, the flexible film substrate 1 will first generate bending vibration. Due to the non-uniform distribution of the variable stiffness patch 3 on its surface, the film generates large-amplitude, multi-modal flow-induced vibration. The piezoelectric polymer PVDF film then bends repeatedly, effectively stimulating the piezoelectric element to output electrical energy. The second effect is that the water flow first impacts the zero-buoyancy front blunt body 4, pushing it backward to compress the high-elasticity spring 5. After the spring stores energy, it rebounds, causing the zero-buoyancy front blunt body 4 to oscillate back and forth. This oscillation will further excite the flow-induced vibration of the flexible thin film substrate 1. The two vibration modes are superimposed to achieve the dual excitation of "thin film self-excited vibration + column coupling vibration", which greatly reduces the starting flow velocity and significantly improves the total strain rate and power output of the piezoelectric power generation unit.

[0028] When the device described in this embodiment is in the high-amplitude vibration stage, under the action of continuous water flow, the gradient distribution of the stiffness patch 3 causes the vibration stress to spread uniformly along the length direction of the flexible thin film substrate 1, avoiding stress concentration and improving the service life of the structure. At the same time, the non-uniform stiffness configuration makes the vibration mode of the flexible thin film substrate 1 easier to be excited. The piezoelectric polymer PVDF film will generate piezoelectric charge under repeated bending deformation, and output electrical energy through the electrode leads. The electrical energy is output to the external rectifier energy storage circuit through the conductive terminal to power low-power hydrological monitoring sensors, wireless transmission modules and other equipment. In addition, the welding status of the PVDF electrode leads and the conductive terminal is checked every 6 months to avoid poor contact that leads to a decrease in output.

[0029] The device described in this embodiment regulates the stiffness distribution of the flexible structure by mimicking the non-uniform stiffness distribution characteristics of aquatic organisms, endowing the power-generating film with low start-up flow velocity characteristics. This allows the power-generating film to start up and generate a significant flow-induced vibration response at a low flow velocity, thereby driving the piezoelectric power generation unit to convert mechanical deformation into electrical energy, greatly improving energy conversion efficiency. This power-generating film has the advantages of low start-up flow velocity, strong flow-induced vibration response, and high energy harvesting efficiency. The overall structure is compact and flexible, making it suitable for fluid energy harvesting in various scenarios such as oceans and water conservancy. It can provide continuous and stable self-powered support for various low-power monitoring devices, and is especially suitable for distributed energy harvesting in low-speed water flow environments such as oceans and rivers.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A biomimetic wave-type variable stiffness ocean current power generation device, characterized in that, It includes a front-mounted floating vibration component, a flexible thin film substrate (1), a piezoelectric generator (2), and several stiffness patches (3) with different stiffnesses. The front-mounted floating vibration assembly includes a zero-buoyancy front-mounted blunt body (4), a high-elasticity spring (5), and a fixed component body (6). The flexible thin film substrate (1) includes a first flexible thin film structure (11) and a second flexible thin film structure (12) arranged symmetrically; the piezoelectric generator (2) is disposed in the middle interlayer between the first flexible thin film structure (11) and the second flexible thin film structure (12) to form an integrated flexible power generation thin film body, and the piezoelectric generator (2) is located at one end of the flexible thin film substrate (1); The stiffness patches (3) are symmetrically arranged on both sides of the flexible power generation film body, and each stiffness patch (3) is non-uniformly arranged along the length direction of the flexible power generation film body to form a non-uniform flexible variable stiffness configuration. In the non-uniform flexible variable stiffness configuration, one end of the piezoelectric generator (2) is connected to the zero buoyancy front blunt body (4); the two ends of the zero buoyancy front blunt body (4) are symmetrically provided with mounting hole structures (7), and the high elasticity spring (5) is fixedly connected to the zero buoyancy front blunt body (4) through the mounting hole structure (7), and the two ends of the high elasticity spring (5) are respectively connected to the fixed part body (6) for installation on the riverbed or seabed base; The piezoelectric generator (2) is used to output electrical energy when it bends under external force; The external forces include the flow-induced vibrations generated by the flexible film substrate (1) and the stiffness patch (3) on the piezoelectric generator (2) when the water flow directly impacts the non-uniform flexible variable stiffness configuration, and the vortex-induced oscillations generated by the water flow impact on the non-uniform flexible variable stiffness configuration when the water flow impacts the front floating vibration component.

2. The biomimetic wave-type variable stiffness ocean current power generation device according to claim 1, characterized in that, The zero-buoyancy front blunt body (4) is a cylindrical structure with a hollow cavity formed by a first front blunt body component (41) and a second front blunt body component (42) arranged symmetrically.

3. The biomimetic wave-type variable stiffness ocean current power generation device according to claim 1, characterized in that, The piezoelectric generator (2) is made of piezoelectric polymer PVDF film.

4. A biomimetic wave-type variable stiffness ocean current power generation device according to claim 2, characterized in that, The materials of the flexible film substrate (1) include, but are not limited to, polyimide and polydimethylsiloxane.

5. A biomimetic wave-type variable stiffness ocean current power generation device according to claim 3, characterized in that, The fixed part (6) is provided with a conductive terminal for connecting to an external energy storage circuit or electrical equipment. The cylindrical structure is provided with a lead wire through hole. The electrode lead wire at the end of the piezoelectric generator (2) is connected to the conductive terminal through the lead wire through hole and then welded. A waterproof and anti-corrosion protective layer is then applied.

6. A biomimetic wave-type variable stiffness ocean current power generation device according to claim 4, characterized in that, The thickness of each stiffness patch (3) is 0.05-0.8 mm, and the total attachment area of ​​any stiffness patch (3) accounts for 20%-30% of the surface area of ​​one side of the flexible film substrate (1).

7. A biomimetic wave-type variable stiffness ocean current power generation device according to claim 5, characterized in that, It also has a flexible adhesive layer, and the rigid patch (3) is fixedly connected to the outer surface of the flexible film substrate (1) through the flexible adhesive layer.

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