Programmable nonlinear restoring force electromagnetic vibration energy harvester and design method

Abstract

This invention belongs to the technical field of electromagnetic vibration energy harvesters, specifically disclosing a programmable nonlinear restoring force electromagnetic vibration energy harvester and its design method. It includes a base, a magnetic vibration energy harvesting module mounted on the base, and a programmable restoring force design device. A rolling element is mounted on the programmable restoring force design device, and a raceway is mounted on the coil frame of the magnetic vibration energy harvesting module. The rolling element rotates horizontally left and right along the raceway. The profile curve of the raceway is designed to meet nonlinear requirements, thus constituting the equivalent restoring force of the energy harvester. This invention achieves precise design of the nonlinear force through mathematical design of the raceway's profile surface. This technological breakthrough means that nonlinear forces highly adapted to specific vibration environment requirements can be customized. This invention, through mathematical derivation, achieves precise design of the restoring force, broadening the adaptability of electromagnetic energy harvesting devices to vibration environments.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic vibration energy harvester technology, and in particular to a programmable nonlinear restoring force electromagnetic vibration energy harvester and its design method. Background Technology

[0002] Sensors are currently widely used in many key fields such as agriculture, smart grids and transportation, environmental monitoring, and the military. Given the challenge of large-scale replacement of chemical battery power in the future, the academic community has proposed a sustainable solution: capturing environmental vibration energy and converting it into electrical energy to self-sufficiently power sensors. This vibration energy harvesting technology aims to reduce reliance on traditional batteries and enhance the system's energy autonomy.

[0003] Among various vibration energy harvesters, electromagnetic vibration energy harvesters have attracted much attention due to their wide range of applications. They mainly consist of a permanent magnet, a coil, and a spring oscillator. However, traditional designs, based on linear theory, only exhibit high energy harvesting efficiency near the resonant frequency, with limited bandwidth. To improve performance, researchers have proposed introducing nonlinear restoring forces, utilizing the broadband characteristics of nonlinear vibration to enhance energy harvesting efficiency.

[0004] However, the form of nonlinear forces has a significant impact on the performance of electromagnetic vibration energy harvesters, and improper design can degrade performance. Therefore, it is necessary to comprehensively consider factors such as the energy harvester's own vibration characteristics, environmental vibration levels and frequencies, and rationally optimize the nonlinear force design. Unfortunately, although many current electromagnetic vibration energy harvester patents introduce nonlinear forces, they cannot achieve precise design of these nonlinear forces.

[0005] For example, patent number 202111289977.6, entitled "Nonlinear Piezoelectric Energy Harvesting Device," specifically includes: a magnetic circuit motion unit, a piezoelectric element, a cantilever beam, a wave spring, a second column, a mass block, a magnet bracket, a rectangular base, and a first column; the first column, the second column, and the magnet bracket are vertically mounted on the same side of the rectangular base, with the magnet bracket positioned between the first and second columns; one end of the cantilever beam is fixedly mounted on the first column and designated as the fixed end, while the other end extends to the magnet bracket and is designated as the free end; the wave spring and the mass block are installed inside the second column, with the mass block connected to the wave spring; multiple block-shaped permanent magnets are installed on the free end of the cantilever beam and the magnet bracket, and the piezoelectric element is installed on the fixed end of the cantilever beam; the magnetic circuit motion unit is connected to the mass block; this device increases the amplitude of the energy harvesting device by introducing nonlinear permanent magnetic force, thereby improving the working efficiency of the energy harvesting device and broadening its working bandwidth. This patent introduces a nonlinear force through the magnetic force between two magnets. However, this patent can only change the form of the nonlinear force by adjusting the distance between the magnets, and cannot achieve the precise design of each coefficient in the nonlinear force.

[0006] Similarly, patent number 202110808165.1, entitled "A Nonlinear Multidirectional Piezoelectric Energy Recovery Device," specifically includes a support frame and an irregularly shaped cantilever beam. The irregularly shaped cantilever beam is fixedly connected to the right side of the top inner side of the support frame. A piezoelectric sheet is attached to the top left side of the irregularly shaped cantilever beam, and a first magnet is attached to the top right side of the irregularly shaped cantilever beam. A spring is fixedly connected to the right side of the top of the support frame, and a second magnet is fixedly connected to the top of the spring. This invention introduces magnetic force to construct a nonlinear bistable system, which is beneficial for overcoming potential barriers to achieve inter-well oscillations, generating frequent bistable transition oscillations. It can resonate under vibration excitation over a wide frequency range, thereby greatly improving broadband energy harvesting efficiency. Furthermore, the unique irregularly shaped cantilever beam structure, combined with magnetic excitation, can achieve vibration energy harvesting in three directions, ultimately realizing broadband, multi-dimensional, efficient vibration energy harvesting without real-time adjustment of structural spacing. This patent also uses the method of introducing nonlinear force with magnetism, but it cannot achieve the requirement of precisely designing the nonlinear force.

[0007] Furthermore, patent number 201910643094.7, entitled "A Passive Adaptive Tuning Resonant Vibration Energy Harvesting Device," describes a device that is fixed at a certain angle to one side of a foundation structure. A cantilever beam magnet is fixed to the free end of the cantilever beam, and a foundation structure magnet is fixed to the foundation structure at the corresponding position. The cantilever beam carries a free slider, and a piezoelectric element is attached to the fixed end of the cantilever beam, connected to a load circuit. This invention broadens the resonant frequency of the oscillator to higher frequencies through a nonlinearly stiffening cantilever beam. The sliding of the free slider helps the nonlinear cantilever beam capture high-energy orbits and provides anti-interference capabilities. Adaptive frequency tuning is achieved through a completely passive mechanical method, which is more intelligent than traditional mechanical adjustment methods and more economical, energy-efficient, simple, and stable than circuit-controlled adjustment methods. By adjusting different beam lengths and magnet gaps, it can be applied to different frequency bands. This patent utilizes the geometric nonlinearity of the cantilever beam to generate a gradually stiffening nonlinear force. Patent number 201721076093.1, entitled "A Vibration Energy Harvester," specifically includes a cantilever beam, a mass block located at the free end of the cantilever beam, and a piezoelectric layer on the surface of the cantilever beam. A blocking block corresponding to the position of the mass block is located above the free end of the cantilever beam. The distance between the lowest point of the blocking block and the equilibrium point of the mass block is less than the amplitude of the mass block during normal operation. This invention, by setting a blocking block corresponding to the position of the mass block above the free end of the cantilever beam, allows the mass block to vibrate up and down when the vibration energy of the external environment forces it to vibrate. Since the distance between the blocking block and the equilibrium point of the mass block is d, when the oscillation amplitude of the mass block exceeds d, the mass block will collide with the blocking block, resulting in a constant output amplitude over a wide frequency range and improving the stability of the device output. This patent utilizes the nonlinear force generated by the collision between the mass block at the free end of the cantilever beam and the adjacent blocking block.

[0008] Although the two existing technologies mentioned above each have their own characteristics, they both have difficulty in achieving precise control over the various coefficients in nonlinear forces. Although there are many methods that introduce nonlinear mechanisms, none of them can achieve precise design of nonlinear forces.

[0009] In summary, existing technologies widely recognize that introducing nonlinear forces can improve the efficiency of linear electromagnetic vibration energy harvesters. Therefore, numerous patents have attempted to introduce nonlinear forces into energy harvesters using permanent magnets, geometric nonlinearity, inclined springs, collisions, or combinations thereof. However, a common drawback of these methods is their inability to precisely design the nonlinear forces. This deficiency directly leads to the difficulty in matching the designed electromagnetic vibration energy harvesters to the complex and variable vibration characteristics of the environment, thus limiting their ability to achieve maximum efficiency. Summary of the Invention

[0010] In view of this, the purpose of this invention is to overcome the shortcomings of inaccurate nonlinear force design in the prior art by precisely designing nonlinear forces, thereby significantly improving the working efficiency of electromagnetic vibration energy harvesters and their adaptability to different vibration environments. Therefore, this invention proposes a programmable nonlinear restoring force electromagnetic vibration energy harvester and its design method.

[0011] To achieve the above objectives, the present invention adopts the following technical solution: A programmable nonlinear restoring force electromagnetic vibration energy harvester includes a base and a magnetic vibration energy harvesting module disposed on the base, and further includes a programmable restoring force design device. The programmable restoring force design device includes a plurality of parallel spring supports disposed on the base, a support frame disposed parallel to the spring supports and disposed on the base, a sliding rod whose rear end passes through the plurality of spring supports and whose front end passes through the support frame, a horizontal spring sleeved on the sliding rod and located between the spring supports and the support frame, a rolling fixing member disposed at the front end of the sliding rod, a rolling member disposed at the front end of the rolling fixing member, and a raceway disposed on the coil frame of the magnetic vibration energy harvesting module. The rolling member rotates horizontally left and right along the raceway. The profile curve of the raceway is mathematically designed to meet nonlinear requirements, thus constituting the equivalent restoring force of the energy trap.

[0012] As a further improvement to the above technical solution: An optimized version of the above technical solution is that an adjusting nut is screwed onto the rear end of the slide rod to adjust the pre-compression of the horizontal spring.

[0013] An optimized solution to the above technical solution is to provide a first linear motion mechanism that can slide back and forth within the support frame to ensure that the horizontal spring is only compressed horizontally without deformation.

[0014] An optimized version of the above technical solution is that the magnetic vibration energy harvesting module is provided with a programmable restoring force design device on the left and right sides or one side.

[0015] An optimized version of the above technical solution is that the magnetic vibration energy harvesting module includes a second linear motion mechanism that can slide left and right and is fixedly mounted on the base, a coil frame mounted on the upper end of the second linear motion mechanism, a drive coil mounted inside the coil frame, fixed magnets located on the left and right sides of the coil frame and mounted on a magnet frame fixed on the base, and a load and energy storage circuit device mounted on the base and electrically connected to the drive coil. The left and right movement of the coil frame enables the fixed magnets and the drive coil to form an electromagnetic interaction system.

[0016] An optimized version of the above technical solution is that the profile curve of the raceway is specifically as follows:

[0017]

[0018]

[0019] in The profile curve of the raceway. The motion trajectory curve of the center of the rolling element. For the radius of the rolling element, yes right Take the derivative, yes Upper coordinate point, yes Upper coordinate point, The force applied to the raceway by the rolling element Component of force in direction, Let the stiffness of the horizontal spring be . This is the pre-compression of the horizontal spring.

[0020] An optimized solution to the above technical solution is as follows: Specifically:

[0021]

[0022] in This refers to the elastic potential energy generated by the horizontal spring.

[0023] This invention also provides a design method for a programmable nonlinear restoring force electromagnetic vibration energy harvester, comprising the following steps: Step 1: Determine the required restoring force based on the vibration characteristics of the site environment; Step 2: Select the stiffness of the horizontal spring, the pre-compression of the horizontal spring, and the radius of the rolling element; Step 3: Establish the mapping relationship between the center trajectory of the rolling element and the equivalent restoring force based on the potential energy expression of the pre-compression spring; Step 4: Based on the radius of the rolling element, convert the center trajectory of the rolling element into the raceway profile curve; Step 5: Machin the raceway according to the raceway profile curve; Step 6: Assemble the components.

[0024] An optimized version of the above technical solution is that the vibration characteristics of the on-site environment include frequency, amplitude, and target energy capture bandwidth.

[0025] Compared with existing technologies, the beneficial effects of this invention are: This invention achieves precise design of nonlinear forces by mathematically designing the profile surface of the raceway. This technological breakthrough means that nonlinear forces can be customized to meet specific vibration environment requirements. For example, in ultra-low frequency vibration environments, the first-order coefficient of the nonlinear force can be precisely adjusted to near zero to optimize energy harvesting. In environments with abundant vibration energy, nonlinear forces can be designed to form a multi-stable system, further improving energy harvesting efficiency. Therefore, this invention, through mathematical derivation, achieves precise design of the restoring force, broadening the adaptability of electromagnetic energy harvesting devices to vibration environments. Furthermore, this invention is the first to integrate the target nonlinear restoring force design mechanism based on raceway inversion with the motion mass, electromagnetic damping, and transducer structure of the electromagnetic vibration energy harvester.

[0026] The design method provided by this invention first determines the target equivalent restoring force function based on the target vibration environment, then uses this target equivalent restoring force to inversely solve for the center trajectory of the rolling element, and further calculates the raceway profile curve. The machined raceway, in conjunction with the rolling element and the pre-compression spring, enables the moving parts of the energy trap to obtain a predetermined nonlinear restoring force, thereby allowing the electromagnetic transducer module to operate at the target frequency, low frequency, or multiple steady-state conditions. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall three-dimensional structure of the electromagnetic vibration energy harvester of the present invention; Figure 2 This is a schematic diagram of the overall front view of the electromagnetic vibration energy harvester of the present invention; Figure 3 The rolling center motion trajectory of the rolling element in this invention With raceway profile curve Relationship diagram; Figure 4 This is a schematic diagram of the electromagnetic vibration energy harvester design method of the present invention; Figure 5 This is a schematic diagram of the raceway profile to be processed in application example 1 of the present invention; Figure 6 This is a schematic diagram of the raceway profile to be processed in application example 2 of the present invention; Figure 7 This is a schematic diagram of the raceway profile to be processed in application example 3 of the present invention.

[0028] In the diagram: 1. Base; 2. Spring bracket; 3. Support frame; 4. Sliding rod; 5. Horizontal spring; 6. Rolling fixing component; 7. Rolling component; 8. Raceway; 9. Adjusting nut; 10. First linear motion mechanism; 11. Second linear motion mechanism; 12. Coil frame; 13. Drive coil; 14. Fixed magnet; 15. Magnet frame; 16. Load and energy storage circuit components. Detailed Implementation

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0030] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0032] As attached Figure 1 With appendix Figure 2 As shown, the structure of this technical solution mainly includes two core components: a classic electromagnetic vibration energy harvesting module, used to convert vibration energy into electrical energy; and a programmable restoring force design device, used for precise programming and design of the required nonlinear mechanical characteristics. Both are mounted on the base 1, and their specific descriptions are as follows: The classic electromagnetic vibration energy harvesting module is described as follows: A second linear motion mechanism 11 (such as a linear guide rail-slider) that slides left and right is provided on one side of the upper end of the base 1. A coil frame 12 is installed on the slider of the second linear motion mechanism 11, and a drive coil 13 is fixed inside the coil frame 12. At the front and rear ends of the second linear motion mechanism 11, magnet frames 15 are provided. Fixed magnets 14 (which can be configured to be of the same pole or opposite poles) are provided on the opposite surfaces of the two magnet frames 15. The fixed magnets 14 are located in the middle area of ​​the drive coil 13. The fixed magnets 14 and the drive coil 13 on the coil frame 12 form an electromagnetic interaction system. At the same time, a load and energy storage circuit 16 is also provided on the base 1. The load and energy storage circuit 16 is electrically connected to the drive coil 13. When the coil frame 12 vibrates back and forth along the second linear motion mechanism 11, an induced current will be generated in the drive coil 13, and the electrical energy will be stored through the load and energy storage circuit.

[0033] The programmable restoring force design device is described as follows: A parallel spring bracket 2 and a support frame 3 are provided on the other side of the upper end of the base 1. Although only one spring bracket 2 is shown in the figure, it can be added as needed to ensure the linear sliding of the sliding rod 4. The two ends of the sliding rod 4 pass through the spring bracket 2 and the support frame 3 respectively. A horizontal spring 5 is sleeved on the sliding rod 4, located between the spring bracket 2 and the support frame 3. An adjusting nut 9 is screwed onto the sliding rod 4 near the outer side of the spring bracket 2, mainly for fine adjustment of the initial pre-compression of the horizontal spring 5. Meanwhile, a first linear motion mechanism 10 (which can be a linear bearing) is set inside the support frame 3, mainly to ensure that the sliding rods 4 slide back and forth, thereby ensuring that the horizontal springs 5 ​​perform linear displacement without bending deformation; A rolling fixing member 6 is provided on the sliding rod 4 near the outer side of the support frame 3. A rolling member 7 (roller or ball) is provided at the front end of the rolling fixing member 6. At the same time, a raceway 8 is provided on the coil frame 12. The rolling member 7 is always in contact with the contour surface of the raceway 8 and can roll on the raceway 8. The contour of the raceway 8 is not a circular arc, a straight inclined plane or an empirical curve, but is calculated in reverse according to the preset target equivalent restoring force function, so that the component force of the rolling member 7 applied to the coil frame 12 in the direction of movement by the pre-compression spring matches the target equivalent restoring force function.

[0034] The working principle of the programmable design restoring force electromagnetic vibration energy harvester of this technical solution is as follows: In the initial configuration stage, by adjusting the position of the coil frame 12, the rolling element 7 is ensured to be located at the center of the raceway 8.

[0035] Subsequently, when the base 1 is subjected to vibration excitation along the direction (left and right movement) of the second linear motion mechanism 11, the excitation will drive the coil 13 to generate corresponding vibration, thereby causing the rolling element 7 to roll on the raceway 8.

[0036] During this process, the pre-compressed horizontal spring 5 applies a nonlinear reaction force to the raceway 8 through the rolling element 7. By carefully designing the geometric profile of the raceway 8, the component force acting on the raceway 8 along the direction of the linear guide can be precisely controlled and designed. This component force constitutes the equivalent restoring force of the energy trap.

[0037] As can be seen from the above, the core of this technical solution lies in the precise mathematical design of the profile shape of the raceway 8, thereby realizing the application of nonlinear forces. By precisely designing this equivalent restoring force to adapt to environmental conditions, the overall performance of the energy harvester under various working conditions can be significantly improved. The specific design scheme is as follows: Let the profile curve of raceway 8 be expressed in functional form as follows: Meanwhile, the trajectory of the center of the rolling element 7 as it rolls on the raceway 8 is defined as another function. .

[0038] Through rigorous mathematical derivation, as shown in the appendix. Figure 3 As shown, and They satisfy a specific functional association:

[0039] (1) In the formula, The radius of the rolling element is 7. yes Upper coordinate point; yes Upper coordinate point; yes right Take the derivative.

[0040] Let the rolling displacement of the rolling element 7 on the raceway 8 be... The potential energy generated by the horizontal spring 5 is: (2) In the formula, The stiffness of the horizontal spring 5; The pre-compression of the horizontal spring 5 (adjusted by adjusting nut 9). The force applied by the rolling element 7 to the raceway 8 The component of the force in the direction can be expressed as: (3) set up =0, from equation (3) we can get: (4) Based on this analysis, equation (4) successfully constructs the restoring force. The trajectory of the center of the rolling element 7 The mathematical connection between them.

[0041] Furthermore, by combining the information already explained in equation (1) and The correspondence between them can be derived With the profile curve of raceway 8 The precise relationship between them. This means that the contour curve of raceway 8 is carefully designed. Its shape allows for flexible application of any desired restoring force. The precise generation of .

[0042] This conclusion not only deepens the understanding of the restoring force regulation mechanism, but also provides a basic theoretical and mathematical basis for the design of the 8-roller profile, thus meeting the specific requirements for restoring force in different application scenarios.

[0043] Therefore, the main design step for the energy trap in this technical solution is to first determine the outline of the raceway 8, as shown in the attached figure. Figure 4 As shown, its design method is mainly as follows: Step 1: Based on the vibration characteristics of the on-site environment, specifically, obtain the frequency, amplitude, and target energy capture bandwidth of the target vibration environment. Then, determine the required restoring force based on the moving mass, electromagnetic damping, spring stiffness, and target vibration environment. Step 2: Select the stiffness of the horizontal spring 5, the pre-compression of the horizontal spring 5, and the radius of the rolling element 7; Step 3: Establish the mapping relationship between the center trajectory of the rolling element 7 and the equivalent restoring force according to the potential energy expression of the pre-compressed spring in formula (4); Step 4: Based on the radius of the rolling element 7, convert the center trajectory of the rolling element 7 into the profile curve of the raceway 8 according to formula (1); Step 5: Machining raceway 8 according to the outline curve of raceway 8; Step 6: Assemble the components.

[0044] To further elaborate and explain the profile design of raceway 8, the following specific examples are provided: Application Example 1 Horizontal spring with 5 stiffness The pre-compression amount is 100 N / m. The radius of the roller 77 is 7mm, and the diameter of the roller is 10mm. The participating mass m of the electromagnetic vibration energy harvester is 0.1kg (the participating mass includes the roller 8, coil frame 12, and drive coil 13), and the ambient vibration frequency f is 5Hz. According to vibration theory, the vibration energy harvesting efficiency is maximized when the participating mass resonates. Therefore... It can be determined by the following formula: (5) After substituting the parameters, we get: (6) Substituting equation (6) into equations (4) and (1), the center trajectory of the rolling element 7 can be obtained. and the profile curve of raceway 8 As attached Figure 5 As shown.

[0045] After the precision machining of raceway 8 is completed, an electromagnetic vibration energy harvester that can achieve maximum vibration energy harvesting efficiency under a 5Hz frequency vibration environment can be constructed by assembling all the components.

[0046] Application Example 2 Horizontal spring with 5 stiffness The pre-compression amount is 100 N / m. The radius of the rolling element 7 is 7mm, and the radius of the roller 8 is 10mm. The participating mass m of the electromagnetic vibration energy harvester is 0.1kg (the participating mass includes the roller 8, coil frame 12, and drive coil 13). The ambient vibration frequency is very low, almost zero. Therefore, according to vibration theory, the optimal frequency is when the natural frequency of the participating system is close to zero. Considering that the system vibration amplitude will be very large at this time, a higher-order restoring force is needed for limiting the movement. Therefore... It can be determined as the following formula: (7) Substituting equation (7) into equations (4) and (1), the center trajectory of the rolling element 77 can be obtained. and the profile curve of raceway 88 As attached Figure 6 As shown.

[0047] After the raceway 8 is machined and all components are successfully assembled, the resulting electromagnetic vibration energy harvester can exhibit the maximum vibration energy harvesting efficiency in a near-zero frequency vibration environment.

[0048] Application Example 3: Assuming the horizontal spring has a stiffness of 5... The pre-compression amount is 100 N / m. The radius of the rolling element 7 is 7mm, and the vibrating mass m of the electromagnetic vibration energy harvester is 0.1Kg (the vibrating mass includes the raceway 8, coil frame 12, and drive coil 13). Assuming the amplitude of the vibration excitation source in the environment is very large, the electromagnetic vibration energy harvester can be designed as a bistable system to better adapt to strong vibration environments. This can be expressed as the following formula: (8) The system is a bistable system, with the two equilibrium points spaced apart by -10mm and 10mm, respectively. Substituting equation (8) into equations (4) and (1), the center trajectory of the rolling element 77 can be obtained. and the profile curve of raceway 88 As attached Figure 7 As shown.

[0049] After precision machining of raceway 8, the assembly of various components yields a vibration energy trap with dual stable points.

[0050] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A programmable nonlinear restoring force electromagnetic vibration energy harvester, comprising a base (1) and a magnetic vibration energy harvesting module disposed on the base (1), characterized in that, It also includes a programmable restoring force design device, which includes a plurality of parallel spring supports (2) arranged on the base (1), a support frame (3) parallel to the spring supports (2) and arranged on the base (1), a sliding rod (4) with its rear end passing through the plurality of spring supports (2) and its front end passing through the support frame (3), a horizontal spring (5) sleeved on the sliding rod (4) and located between the spring supports (2) and the support frame (3), a rolling fixing member (6) arranged at the front end of the sliding rod (4), a rolling member (7) arranged at the front end of the rolling fixing member (6), and a raceway (8) arranged on the coil frame (12) of the magnetic vibration energy harvesting module. The rolling member (7) rotates horizontally left and right along the raceway (8). The profile curve of the raceway (8) is designed mathematically to meet nonlinear requirements and constitutes the equivalent restoring force of the energy trap.

2. The programmable nonlinear restoring force electromagnetic vibration energy harvester according to claim 1, characterized in that, The sliding rod (4) has an adjusting nut (9) screwed to its rear end for adjusting the pre-compression of the horizontal spring (5).

3. The programmable nonlinear restoring force electromagnetic vibration energy harvester according to claim 1, characterized in that, A first linear motion mechanism (10) that can slide back and forth is provided in the support frame (3) to ensure that the horizontal spring (5) is only compressed horizontally without deformation.

4. The programmable nonlinear restoring force electromagnetic vibration energy harvester according to any one of claims 1 to 3, characterized in that, The magnetic vibration energy harvesting module is equipped with a programmable restoring force design device on its left and right sides or one side.

5. The programmable nonlinear restoring force electromagnetic vibration energy harvester according to claim 4, characterized in that, The magnetic vibration energy harvesting module includes a second linear motion mechanism (11) that can slide left and right and is fixedly mounted on the base (1), a coil frame (12) mounted on the upper end of the second linear motion mechanism (11), a drive coil (13) mounted in the coil frame (12), fixed magnets (14) located on the left and right sides of the coil frame (12) and mounted on a magnet frame (15) fixed on the base (1), and a load and energy storage circuit (16) mounted on the base (1) and electrically connected to the drive coil (13). The left and right movement of the coil frame (12) enables the fixed magnets (14) and the drive coil (13) to form an electromagnetic interaction system.

6. The programmable nonlinear restoring force electromagnetic vibration energy harvester according to claim 1, characterized in that, The specific profile curve of the raceway (8) is as follows: in The profile curve of raceway (8), The motion trajectory curve of the center of the rolling element (7), The radius of the rolling element (7) is... yes right Take the derivative, yes Upper coordinate point, yes Upper coordinate point, The force applied to the raceway (8) by the rolling element (7) Component of force in direction, The stiffness of the horizontal spring (5) is... The pre-compression of the horizontal spring (5) is given.

7. The programmable nonlinear restoring force electromagnetic vibration energy harvester according to claim 6, characterized in that, The Specifically: in The elastic potential energy generated by the horizontal spring (5).

8. A design method for the programmable nonlinear restoring force electromagnetic vibration energy harvester as described in claim 7, characterized in that, Includes the following steps: Step 1: Determine the required restoring force based on the vibration characteristics of the site environment; Step 2: Select the stiffness of the horizontal spring (5), the pre-compression of the horizontal spring (5), and the radius of the rolling element (7); Step 3: Establish the mapping relationship between the center trajectory of the rolling element (7) and the equivalent restoring force based on the potential energy expression of the pre-compressed spring; Step 4: Based on the radius of the rolling element (7), convert the center trajectory of the rolling element (7) into the profile curve of the raceway (8); Step 5: Machin the raceway (8) according to the outline curve of the raceway (8); Step 6: Assemble the components.

9. The programmable nonlinear restoring force electromagnetic vibration energy harvester according to claim 1, characterized in that, The vibration characteristics of the field environment include frequency, amplitude, and target energy capture bandwidth.

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