Multi-direction self-adaptive piezoelectric energy harvester and energy harvesting method thereof

Abstract

The invention discloses a multi-direction self-adaptive piezoelectric energy harvester and an energy harvesting method. The energy harvesting method comprises the steps that one end of a main beam is fixed through a clamp; the shear mode piezoelectric piece is mounted on the surface of the main beam; the energy triggering assembly comprises a triggering piece, and the triggering piece is installed at one end of the main beam and provided with a triggering curved surface and a triggering rolling body moving in the mode of being attached to the triggering curved surface. When the piezoelectric energy harvester is subjected to vibration excitation perpendicular to or deviating from the thickness direction of the main beam, the triggering rolling body can roll in the triggering curved surface. In the process of triggering the rolling body to roll, the overall gravity center of the piezoelectric energy harvester shifts, the structure of the main beam is forced to generate torsional deformation, and the shear mode piezoelectric piece converts vibration energy in the environment into electric energy. According to the invention, vibration energy in multiple directions can be effectively captured only by using a single piezoelectric material, so that an efficient energy collection function is realized, the preparation difficulty is reduced, the cost performance of a product is improved, and a solid economic feasibility foundation is provided for large-scale industrial production and wide application.

Description

Technical Field

[0001] The invention belongs to the technical field of vibration energy recovery and piezoelectric power generation, and relates to a configuration of a multi-directional adaptive piezoelectric energy harvester and an energy harvesting method thereof. Background Art

[0002] A piezoelectric energy harvester is a device that converts mechanical vibration energy into electrical energy using the positive piezoelectric effect. It has the characteristics of efficient and sustainable energy recovery and plays an important role in green energy, wireless sensor networks and vibration monitoring systems.

[0003] The main problems of existing piezoelectric energy harvesters are:

[0004] 1) Single application scenario: Some piezoelectric energy harvesters are difficult to adapt to multi-directional vibration environments. This sensitivity to the vibration direction limits the application of piezoelectric energy harvesters in complex vibration environments, reducing their practicality and flexibility. For example: Patent CN109039156A uses the bending-torsion coupling deformation of an asymmetric structure to capture vibration energy along the thickness direction of the main beam. When the vibration direction changes from the thickness direction of the main beam to the width direction of the main beam, the energy conversion efficiency of the energy harvester will be greatly reduced. Patent CN107733284A combines piezoelectric and electromagnetic energy harvesting mechanisms to design a two-degree-of-freedom hybrid energy harvester. Although the output power is increased, it can only capture vibration energy in the vertical direction (spring axial direction).

[0005] 2) Complex structure and high cost: In order to overcome the problem of vibration direction sensitivity, multi-directional piezoelectric energy harvesters often adopt complex structures and require a large amount of piezoelectric materials, which leads to increased manufacturing costs and reduced energy conversion efficiency, resulting in poor cost performance.

[0006] In view of the specific problems of low energy conversion efficiency and limited energy capture direction of existing piezoelectric energy harvesters, research on new configurations of multi-directional piezoelectric energy harvesters has been carried out. For example, patent CN114584002A arranges three cantilevers to realize three-directional energy capture of piezoelectric energy harvesters, but when subjected to lateral force and torque, the performance of the energy harvester decreases. The multi-directional energy harvester proposed in patent CN114006550A has significant directional sensitivity: when the vibration direction is at an angle of 45° with the x-axis, the energy harvester can generate a high voltage of nearly 20V; but when the vibration direction is at an angle of 45° with the z-axis, its maximum voltage drops sharply to about 3V. The multi-directional vibration energy harvesters proposed in patents CN111884543A and CN117277870A have effectively overcome the limitations of the existing structure with a single energy capture direction and low output voltage; however, the design of multiple vibration energy harvesting units increases the complexity of the structure and the preparation cost, and it is difficult to achieve the adaptive function of the vibration direction. In addition, in the design of the multi-directional vibration energy harvester, the motion trajectory of the mass oscillator involved in patent CN219394719U is difficult to accurately control to a certain extent, which directly affects the energy conversion efficiency in the energy harvesting process. In addition, patent CN219394719U is difficult to ensure the fit between the spring end and the piezoelectric ceramic surface during the preparation process, which limits the durability and reliability of the energy harvester in long-term operation. In addition, the above-mentioned energy harvester mainly relies on the single bending deformation mode of the piezoelectric material in the vibration response, which may limit the energy collection efficiency and adaptability of the energy harvester in complex and changeable vibration environments.

[0007] In view of the research limitations of existing multi-directional piezoelectric energy harvesters, this paper proposes a configuration and energy harvesting method of a multi-directional adaptive piezoelectric energy harvester. Summary of the invention

[0008] The piezoelectric energy harvester designed in the present invention aims to solve the problems of low energy collection efficiency, high sensitivity to vibration direction and limited application scenarios existing in existing energy harvesters.

[0009] In order to solve the above technical problems, the inventors have obtained the technical solution of the present invention through practice and summary. The present invention adopts the following technical solution:

[0010] A multi-directional adaptive piezoelectric energy harvester, comprising:

[0011] A main beam, one end of which is fixed by a clamp;

[0012] A shear mode piezoelectric element, wherein the shear mode piezoelectric element is mounted on the surface of the main beam;

[0013] An energy trigger assembly, the energy trigger assembly comprises a trigger member, the trigger member is mounted at one end of the main beam and is provided with a trigger curved surface and a trigger rolling body that moves in accordance with the trigger curved surface;

[0014] When the piezoelectric energy harvester is subjected to vibration excitation perpendicular to or deviating from the thickness direction of the main beam, the trigger rolling body can roll within the triggering curved surface;

[0015] The displacement of the overall center of gravity of the piezoelectric energy harvester caused by the rolling of the triggering rolling body forces the structure of the main beam to undergo torsional deformation, and the shear mode piezoelectric element converts the vibration energy in the environment into electrical energy.

[0016] Preferably, a path guiding structure is provided on the surface of the triggering curved surface, for guiding the motion trajectory of the triggering rolling body during the vibration process;

[0017] When the piezoelectric energy harvester is subjected to vibration excitation perpendicular to or deviating from the thickness direction of the main beam, the trigger rolling body can roll along the path guiding structure within the triggering curved surface.

[0018] Preferably, the path guiding structure is a groove or two parallel convex ridges.

[0019] The main function of the path guiding structure is to effectively guide the movement trajectory of the ball during the vibration process. When the piezoelectric energy harvester is subjected to vibration excitation perpendicular to the thickness direction of the main beam, the trigger rolling body (for example, a ball) can roll along a predetermined path in the curved surface structure. By utilizing the displacement of the overall center of gravity of the piezoelectric energy harvester caused by the trigger rolling body during the rolling process, the main beam structure is effectively forced to undergo torsional deformation, and the piezoelectric material attached to the main beam can make full use of the torsional deformation caused by the vibration to efficiently output electrical energy, thereby achieving the purpose of converting the vibration energy in the environment into usable electrical energy.

[0020] In a preferred solution, the main beam comprises a sandwich beam, a filling groove is provided on the sandwich beam, and the upper and lower surfaces of the sandwich beam are covered with a surface beam.

[0021] In a preferred solution, the filling groove is uniformly and densely filled with a low shear modulus body, and the shear modulus of the low shear modulus body is lower than the shear modulus of the sandwich beam.

[0022] During the energy capture period, since the main beam needs to have a certain torsional stiffness but also needs to take into account the energy capture efficiency, the torsional stiffness cannot be too large, which is not conducive to torsional deformation, thereby making the energy capture efficiency low; the torsional stiffness cannot be too small, which will lead to poor structural strength and durability, resulting in energy capture failure. Therefore, the inventors solve the contradiction between torsional stiffness and energy capture efficiency by designing the main beam structure in a targeted manner, and the following effects are obtained:

[0023] 1) Accurately perform slotting operations on the beam. The location and size of the slots can be determined through theoretical analysis, numerical calculation or experiments to ensure that the main beam has sufficient structural strength and long service life while meeting functional requirements.

[0024] 2) Fill the opened grooves with materials with lower shear modulus (for example, polyethylene, polypropylene or soft magnetic alloys, etc.). The goals of this material selection strategy are: first, to optimize and simplify the preparation process of the overall structure, and second, to significantly enhance or improve the mechanical properties of the structure. For example, because materials with lower shear modulus are easy to shape and fill, the complexity and cost of the preparation process can be significantly reduced. This type of material is not only easy to adapt to various groove designs, but also can effectively avoid preparation difficulties caused by material stress concentration, ensuring the consistency and reliability of the structure. In addition, under the action of shear stress, these materials can effectively slow down stress transfer and reduce stress concentration inside the structure, thereby significantly improving the fatigue durability of the structure under long-term use.

[0025] 3) A thin layer of metal is evenly covered on the upper and lower surfaces of the beam, so that the rectangular beam forms a structurally complete and stable main beam as a whole. Using this construction method, by adjusting the parameters such as the slot position, depth, width, spacing, and selecting appropriate filling materials based on factors such as elastic modulus, shear modulus, and density, the torsional stiffness of the main beam can be effectively reduced, thereby improving the energy capture efficiency of the main beam.

[0026] Preferably, the shear mode piezoelectric element is made of shear mode piezoelectric fiber reset material, model M-8528-F1 piezoelectric material, and the piezoelectric material is firmly adhered to the main beam by adhesive to ensure that electrical energy can be effectively output when the main beam vibrates and deforms.

[0027] Preferably, the polarization direction of the shear mode piezoelectric element is perpendicular to the direction of the electric field.

[0028] Preferably, one end of the main beam is a clamping end and the other end is a mounting end, the clamp is connected at the clamping end, the trigger member is connected at the mounting end, the clamping end and the main beam are integrally formed, or connected by disassembly or bonding.

[0029] A method for harvesting energy using a multi-directional adaptive piezoelectric energy harvester, comprising the following steps:

[0030] Step 1: Main beam production

[0031] Slot the beams according to the pre-designed slotting scheme, and strictly control the slotting position and dimensional accuracy;

[0032] The selected low shear modulus body is uniformly and densely filled in the filling groove to obtain a sandwich beam;

[0033] The upper and lower surfaces of the sandwich beam are covered with surface beams to obtain a main beam;

[0034] A triggering curved surface and a path guiding structure located on the surface of the triggering curved surface are processed on the triggering member;

[0035] Step 2: Piezoelectric energy harvester assembly

[0036] The clamping end of the main beam and the fixture are reliably clamped to ensure that the clamping force is moderate and stable, and the installation end is firmly connected to the triggering member;

[0037] A trigger rolling body is placed inside the trigger member to ensure that the trigger rolling body can roll freely and smoothly within the trigger curved surface;

[0038] Step 3, Calibration

[0039] The thickness direction of the main beam is strictly perpendicular to the ambient vibration direction. Under the action of the ambient vibration, the trigger rolling body inside the trigger part receives the excitation vibration, and the guiding structure starts the rolling mode along the pre-designed path inside the trigger part.

[0040] Step 4: Energy capture

[0041] When the direction of environmental vibration is perpendicular to the thickness direction of the piezoelectric energy harvester, the dynamic rolling of the rolling body is triggered, causing the overall center of gravity of the piezoelectric energy harvester to shift. A torque will be generated inside the piezoelectric energy harvester, which acts on the main beam, forcing the main beam to twist and deform, thereby outputting electrical energy.

[0042] When the direction of the environmental vibration deviates at a certain angle around the thickness direction of the piezoelectric energy harvester, the trigger rolling element can still cause torsional deformation of the main beam under the continuous excitation of the environmental vibration.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1) Simple structure and low cost. The multi-directional piezoelectric energy harvester designed by the present invention can effectively capture vibration energy in multiple directions by using only a single piezoelectric material, which is conducive to realizing efficient energy harvesting function, reducing the difficulty of preparation, and improving the cost performance of the product, providing a solid economic feasibility foundation for large-scale industrial production and wide application.

[0045] 2) Easy integration. The multi-directional adaptive piezoelectric energy harvester has a flexible structure and is easy to integrate with other devices, effectively reducing the overall complexity of the system. This design facilitates rapid deployment and flexible configuration in practical applications, providing strong technical support and guarantee for the rapid construction and optimization and upgrading of energy harvesting systems.

[0046] 3) Multi-directional adaptive function. The present invention utilizes the overall center of gravity shift of the piezoelectric energy harvester caused by the rolling of the trigger rolling body, effectively forcing the main beam to undergo torsional deformation, and the shear mode piezoelectric fiber composite material pasted on the main beam can fully utilize the torsional deformation caused by vibration and efficiently output electrical energy, thereby achieving the purpose of converting the vibration energy in the environment into usable electrical energy. In addition, the design of the guide path structure can optimize the movement path of the trigger rolling body, making it easier to move to a position with higher energy output, thereby overcoming the shortcomings of low energy collection efficiency and limited performance improvement of traditional piezoelectric energy harvesters.

[0047] 4) Broad application prospects. The multi-directional adaptive piezoelectric energy harvester can convert vibration energy in the environment into electrical energy, providing reliable power support for wireless sensors and portable electronic devices in the fields of IoT devices, wearable devices, smart sensors, etc. It is simple and easy to integrate, which helps to reduce system complexity and cost, achieve energy self-sufficiency, and has broad market application prospects and social value.

[0048] Based on the above reasons, the present invention can be widely used in the fields of vibration energy recovery technology and piezoelectric power generation technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a structural schematic diagram of a multi-directional adaptive piezoelectric energy harvester of the present invention;

[0050] Figure 2 It is a schematic diagram of the main beam structure of the present invention;

[0051] Figure 3 It is a schematic diagram of the structure of the trigger member of the present invention.

[0052] In the figure: 1. Clamping end; 2. Shear mode piezoelectric component; 3. Main beam; 4. Bolt; 5. Trigger component; 6. Path guide structure; 7. Trigger rolling element; 8. Nut; 9. Upper beam; 10. Sandwich beam; 11. Lower beam. DETAILED DESCRIPTION

[0053] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0054] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0055] Example 1

[0056] like Figure 1 As shown, a multi-directional adaptive piezoelectric energy harvester comprises:

[0057] A main beam 3, one end of which is fixed by a clamp;

[0058] A shear mode piezoelectric element 2, wherein the shear mode piezoelectric element 2 is mounted on the surface of the main beam 3;

[0059] An energy trigger component, the energy trigger component comprises a trigger member 5, the trigger member 5 is mounted at one end of the main beam 3 and is provided with a trigger curved surface and a trigger rolling body 7 that moves in accordance with the trigger curved surface;

[0060] When the piezoelectric energy harvester is subjected to vibration excitation perpendicular to or deviating from the thickness direction of the main beam 3, the trigger rolling body 7 can roll within the triggering curved surface;

[0061] The displacement of the overall center of gravity of the piezoelectric energy harvester caused by the rolling of the triggering rolling body 7 forces the structure of the main beam 3 to undergo torsional deformation, and the shear mode piezoelectric element 2 converts the vibration energy in the environment into electrical energy.

[0062] Example 2

[0063] In the above-mentioned scheme, if Figure 1 As shown, a path guiding structure 6 is provided on the surface of the triggering curved surface, for guiding the motion trajectory of the triggering rolling body 7 during the vibration process;

[0064] When the piezoelectric energy harvester is subjected to vibration excitation perpendicular to or deviating from the thickness direction of the main beam 3 , the rolling body 7 is triggered to roll along the path guiding structure 6 within the triggering curved surface.

[0065] The path guiding structure 6 is a groove or two parallel ridges. Of course, the groove can be a track groove set along the surface of the triggering curved surface, or it can be an irregular curved groove. The guiding trajectory is determined according to the excitation direction. As long as the movement path of the triggering rolling body can be optimized, it can be easier to move to a position with higher energy output.

[0066] Taking the groove as an example, groove 6 is a concave part on the trigger surface. According to the design requirements and excitation parameters (for example, the intensity and direction of the excitation), the width, depth, position and other parameters of the initial groove can be optimized through theoretical analysis, numerical calculation and experiments to improve the energy conversion efficiency of the energy harvester.

[0067] In actual application, the piezoelectric energy harvester configuration of the present invention can be further optimized and adjusted according to the specific characteristics of the vibration environment and the energy recovery requirements to meet the energy requirements in different vibration scenarios. For example, when the excitation force increases, in order to ensure that the trigger rolling body 7 continues to roll stably in the trigger surface, it is necessary to appropriately extend the rolling path of the trigger surface or increase the length and complexity of the trigger surface (such as Figure 3 As shown, multiple triggering curved surfaces are used, and arc curved surfaces are used for transition between the multiple triggering curved surfaces, and the radius of the curved surface gradually decreases from bottom to top. This method is used in the case where the size of the trigger member 5 is limited). When the exciting force decreases, in order to ensure the stability of the captured power, the torsional amplitude of the main beam 2 can be increased by selecting a filling material or a sandwich beam material with a smaller shear stiffness, thereby improving the energy conversion efficiency.

[0068] Example 3

[0069] In the above-mentioned scheme, if Figure 2 As shown, the main beam 3 includes a sandwich beam 10, a filling groove is opened on the sandwich beam 10, and the upper and lower surfaces of the sandwich beam 10 are covered with surface beams. The two surface beams are an upper beam 9 and a lower beam 11 respectively. Suitable process means such as electroplating and spraying can be used between the sandwich beam 10 and the surface beam to ensure the uniformity and adhesion of the metal layer, thereby forming a complete main beam structure.

[0070] The filling groove is uniformly and densely filled with a low shear modulus body, and the shear modulus of the low shear modulus body is lower than the shear modulus of the sandwich beam 10 .

[0071] The torsional stiffness of the main beam 3 can be effectively reduced by selecting the slot position and size and material filling on the sandwich beam 10. Under the same excitation conditions, the reduction of the torsional stiffness of the main beam 3 will directly lead to an increase in its torsional deformation, which will further increase the energy output of the shear mode piezoelectric fiber composite material according to the piezoelectric effect principle. This improvement can provide a reliable energy source for equipment or systems that require a stable energy supply.

[0072] Example 4

[0073] In the above-mentioned scheme, if Figure 1 As shown, the shear mode piezoelectric element 2 is made of a shear mode piezoelectric fiber reset material and is tightly adhered to the surface of the main beam 3 by an adhesive. It can be the upper surface or the lower surface.

[0074] The polarization direction of the shear mode piezoelectric element 2 is perpendicular to the electric field direction. It can be one group or multiple groups, depending on the design requirements. And with the help of advanced optimization algorithms, comprehensive consideration of structural mechanical characteristics, vibration environment parameters, energy conversion efficiency requirements and other factors, the relevant parameters of the shear mode piezoelectric element 2 can be deeply optimized to determine the optimal number and parameter configuration to achieve the best energy capture effect.

[0075] Example 5

[0076] In the above-mentioned scheme, if Figure 1 As shown, one end of the main beam 3 is the clamping end 1 and the other end is the mounting end. The clamp is connected to the clamping end 1 by bolts and nuts, and the trigger member 5 is connected to the mounting end by bolts and nuts. The clamping end 1 is integrally formed with the main beam 3, or is connected by disassembly or bonding.

[0077] One end of the main beam 3 (i.e., the clamping end 1 of the beam) is reliably clamped by a clamp to ensure that the clamping force is moderate and stable, and the other end (i.e., the mounting end) is connected to the trigger member 5. If bolts 4-nuts 8 are used for connection, bolts 4 and nuts 8 of appropriate specifications need to be selected, and tightened according to standard connection processes to ensure the firmness and reliability of the connection; if adhesive connection is used, adhesives that match the connection materials need to be selected and operated according to the instructions for use of the adhesives to ensure that the bonding strength of the connection parts meets the requirements.

[0078] Example 6

[0079] like Figures 1 to 3 As shown, a method for harvesting energy by a multi-directional adaptive piezoelectric energy harvester comprises the following steps:

[0080] Step 1: Main beam 3 production

[0081] Slot the beams according to the pre-designed slotting scheme, and strictly control the slotting position and dimensional accuracy;

[0082] The selected low shear modulus body is uniformly and densely filled in the filling groove to obtain a sandwich beam 10;

[0083] The upper and lower surfaces of the sandwich beam 10 are covered with surface beams to obtain the main beam 3;

[0084] A triggering curved surface and a path guiding structure 6 located on the surface of the triggering curved surface are processed on the triggering member 5;

[0085] Step 2: Piezoelectric energy harvester assembly

[0086] The clamping end of the main beam 3 and the fixture are reliably clamped to ensure that the clamping force is moderate and stable, and the mounting end is firmly connected to the trigger member 5;

[0087] A trigger rolling body 7 is placed inside the trigger member 5 to ensure that the trigger rolling body 7 can roll freely and smoothly within the trigger curved surface;

[0088] Step 3, Calibration

[0089] The thickness direction of the main beam 3 is strictly perpendicular to the environmental vibration direction. Under the action of the environmental vibration, the trigger rolling body 7 inside the trigger member 5 receives the excitation vibration, and the guiding structure 6 starts the rolling mode along the pre-designed path inside the trigger member 5;

[0090] Step 4: Energy capture

[0091] When the environmental vibration direction is perpendicular to the thickness direction of the piezoelectric energy harvester, the dynamic rolling of the rolling element 7 is triggered, causing the overall center of gravity of the piezoelectric energy harvester to shift, and a torque will be generated inside the piezoelectric energy harvester. The torque acts on the main beam 3, forcing the main beam 3 to twist and deform, thereby outputting electrical energy.

[0092] When the direction of the environmental vibration deviates by a certain angle around the thickness direction of the piezoelectric energy harvester, the trigger rolling body 7 can still cause the torsional deformation of the main beam 3 under the continuous excitation of the environmental vibration.

[0093] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. The replacement may be a replacement of a part of the structure, device, method step, or a complete technical solution. Any equivalent replacement or change according to the technical solution and the inventive concept of the present invention shall be covered within the protection scope of the present invention.

Claims

1. A multi-directional adaptive piezoelectric energy harvester, characterized in that: include: A main beam (3), one end of the main beam (3) being fixed by a clamp; A shear mode piezoelectric element (2), wherein the shear mode piezoelectric element (2) is mounted on the surface of the main beam (3); An energy trigger component, the energy trigger component comprising a trigger member (5), the trigger member (5) being mounted on one end of the main beam (3) and having a trigger curved surface and a trigger rolling body (7) that moves in conformity with the trigger curved surface; When the piezoelectric energy harvester is subjected to vibration excitation perpendicular to or deviating from the thickness direction of the main beam (3), the trigger rolling body (7) can roll within the trigger curved surface; The displacement of the overall center of gravity of the piezoelectric energy harvester caused by the rolling of the trigger rolling body (7) forces the structure of the main beam (3) to undergo torsional deformation, and the shear mode piezoelectric element (2) converts vibration energy in the environment into electrical energy.

2. The multi-directional adaptive piezoelectric energy harvester according to claim 1, characterized in that: A path guiding structure (6) is provided on the surface of the triggering curved surface, for guiding the movement trajectory of the triggering rolling body (7) during the vibration process; When the piezoelectric energy harvester is subjected to vibration excitation perpendicular to or deviating from the thickness direction of the main beam (3), the trigger rolling body (7) can roll along the path guiding structure (6) within the trigger curved surface.

3. The multi-directional adaptive piezoelectric energy harvester according to claim 2, characterized in that: The path guiding structure (6) is a groove or two convex ridges arranged in parallel.

4. The multi-directional adaptive piezoelectric energy harvester according to claim 1, characterized in that: The main beam (3) comprises a sandwich beam (10), a filling groove is provided on the sandwich beam (10), and the upper and lower surfaces of the sandwich beam (10) are both covered with surface beams.

5. The multi-directional adaptive piezoelectric energy harvester according to claim 4, characterized in that: The filling groove is uniformly and densely filled with a low shear modulus body, and the shear modulus of the low shear modulus body is lower than the shear modulus of the sandwich beam (10).

6. The multi-directional adaptive piezoelectric energy harvester according to claim 1, characterized in that: The shear mode piezoelectric element (2) is made of a shear mode piezoelectric fiber resetting material.

7. The multi-directional adaptive piezoelectric energy harvester according to claim 6, characterized in that: The polarization direction of the shear mode piezoelectric element (2) is perpendicular to the direction of the electric field.

8. The multi-directional adaptive piezoelectric energy harvester according to claim 1, characterized in that: One end of the main beam (3) is a clamping end (1), and the other end is a mounting end; the clamp is connected to the clamping end (1), and the trigger member (5) is connected to the mounting end; The clamping end (1) and the main beam (3) are integrally formed, or connected by disassembly or bonding.

9. The energy harvesting method of a multi-directional adaptive piezoelectric energy harvester according to any one of claims 1 to 8, characterized in that: The steps include: Step 1: Main beam (3) production Slot the beams according to the pre-designed slotting scheme, and strictly control the slotting position and dimensional accuracy; The selected low shear modulus body is uniformly and densely filled into the filling groove to obtain a sandwich beam (10); Covering the upper and lower surfaces of the sandwich beam (10) with surface beams to obtain a main beam (3); A triggering curved surface and a path guiding structure (6) located on the surface of the triggering curved surface are processed on the triggering member (5); Step 2: Piezoelectric energy harvester assembly The clamping end of the main beam (3) and the clamp are reliably clamped to ensure that the clamping force is moderate and stable, and the mounting end is firmly connected to the trigger member (5); A trigger rolling body (7) is placed inside the trigger member (5) to ensure that the trigger rolling body (7) can roll freely and smoothly within the trigger curved surface; Step 3, Calibration The thickness direction of the main beam (3) is strictly perpendicular to the environmental vibration direction. Under the action of the environmental vibration, the trigger rolling body (7) inside the trigger member (5) receives the excitation vibration and guides the structure (6) to start the rolling mode along the pre-designed path inside the trigger member (5); Step 4: Energy capture When the direction of environmental vibration is perpendicular to the thickness direction of the piezoelectric energy harvester, the dynamic rolling of the rolling body (7) is triggered, causing the overall center of gravity of the piezoelectric energy harvester to shift, and a torque is generated inside the piezoelectric energy harvester. The torque acts on the main beam (3), forcing the main beam (3) to undergo torsional deformation and output electrical energy. When the direction of the environmental vibration deviates at a certain angle around the thickness direction of the piezoelectric energy harvester, the trigger rolling body (7) can still cause the torsional deformation of the main beam (3) under the continuous excitation of the environmental vibration.

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