A sensor based on a friction nanogenerator and a preparation method thereof
By designing a sensor based on triboelectric nanogenerators and fabricating the sensor using 3D printing and electrospinning techniques, the problems of inconvenient wear, long production cycle, and high cost have been solved, realizing a sensor that is easy to wear, quick to manufacture, and highly sensitive.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHANDONG UNIV OF SCI & TECH
- Filing Date
- 2023-05-16
- Publication Date
- 2026-07-03
AI Technical Summary
Existing wearable sensors based on triboelectric nanogenerators are inconvenient to wear, have long manufacturing cycles, and are costly to produce.
A sensor comprising a sensor body and a triboelectric device is designed. The bottom and top layers are prepared using 3D printing technology, and a PVDF film is prepared using electrospinning technology. The sensor combines a loss-of-electron layer and an gain-of-electron layer. The slider is connected to a spring and slides in a sliding groove. The sensor is encapsulated using TPU film, which simplifies the manufacturing process.
This enables the sensor to be easily worn, shortens the manufacturing cycle, reduces costs, and can more accurately reflect the slider position, adapt to different working environments, and extend its service life.
Smart Images
Figure CN116817986B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of sensor technology, specifically to a sensor based on a triboelectric nanogenerator and its fabrication method. Background Technology
[0002] Triboelectric nanogenerators can be used to harvest various forms of mechanical energy, such as human movement, mechanical vibration, rotation, wind energy, and sound waves. Furthermore, by converting these mechanical movements into electrical signals, triboelectric nanogenerators can serve as self-powered sensors to detect displacement, velocity, metal ions, humidity, temperature, and ultraviolet light intensity. Triboelectric nanogenerators offer advantages such as high output power, high efficiency, light weight, low material cost, and simple manufacturing. The output of a triboelectric nanogenerator generally exhibits a linear relationship with mechanical motion in the environment. Therefore, sensors based on triboelectric nanogenerators can function as active sensors to detect mechanical disturbances in the environment with extremely high sensitivity.
[0003] Current research on wearable sensors based on triboelectric nanogenerators (TENGs) focuses more on their power generation characteristics, while neglecting their convenience as wearable sensors. Furthermore, existing technologies for this type of sensor have long manufacturing cycles and high production costs.
[0004] Therefore, there is a need for a sensor based on triboelectric nanogenerators that is easy to wear, has a short manufacturing cycle, and low manufacturing cost, as well as a method for its fabrication. Summary of the Invention
[0005] The main objective of this invention is to provide a sensor based on triboelectric nanogenerators and its fabrication method, so as to solve the problems of inconvenience in wearing, long manufacturing cycle and high manufacturing cost of wearable sensors based on triboelectric nanogenerators in the prior art.
[0006] To achieve the above objectives, the present invention provides a sensor based on a triboelectric nanogenerator, comprising: a sensor body and a triboelectric device, wherein the sensor body comprises: a bottom layer and a top layer, and the triboelectric device comprises: a ring structure, a slider and a spring;
[0007] The top layer covers the bottom layer, and there are multiple sliding grooves between the top and bottom layers. The slider is located in the sliding groove. The sidewall of the sliding groove is approximately circular, and there are multiple spaced annular grooves on the sidewall of the sliding groove. The annular grooves are adapted to the shape of the sidewall of the sliding groove, and there is an annular structure inside the annular groove. The slider has a volatile electron layer and a gain electron layer covering the volatile electron layer. The surface of the annular structure that contacts the slider has a volatile electron layer. The length of the sliding groove is greater than the length of the slider. One end of the slider is connected to a spring, and the spring is fixed to the surface of the bottom layer relative to the top layer by a connecting post. Further, the bottom layer is square, and there is a square protrusion structure at each of the four corners of the bottom layer. Each square protrusion structure forms a sliding groove with the adjacent square protrusion structure. Multiple sliding grooves form a "+" shaped structure.
[0008] Furthermore, the connecting post is located at the center of the bottom layer, and the end face of the connecting post away from the bottom layer has a raised "+" shaped connecting structure. The top layer and the bottom layer are the same size and shape, and the center of the top layer has a "+" shaped groove structure. The connecting structure and the groove structure cooperate with each other.
[0009] Furthermore, the four sliders are located in the four sliding grooves respectively, and one end of each of the four sliders is fixedly connected to a spring.
[0010] Furthermore, the upper part of the slider is a cylindrical structure, the lower part is a truncated pyramid structure, and the contact point between the square protrusion and the slider is a trapezoidal structure.
[0011] Furthermore, the volatile electron layer is made of copper tape, and the volatile electron layer is made of PVDF or PI; the length of the annular groove is 0.8cm, the distance between the two annular grooves is 0.2cm, and the length of the slider is 1cm.
[0012] Furthermore, a TPU film is encapsulated on the outer side of both the top and bottom layers.
[0013] A method for fabricating a sensor based on a triboelectric nanogenerator includes the following steps:
[0014] S1 utilizes 3D printing technology to print the bottom layer, top layer, ring structure, and slider according to actual size requirements.
[0015] S2 uses 3D printing technology to print molds for preparing PVDF films.
[0016] S3, mechanically stir PVDF and DMF to obtain PVDF spinning precursor solution.
[0017] S4. The PVDF spinning precursor solution is evenly coated onto the mold using an electrospinning machine. After drying at a constant temperature, the PVDF coating is peeled off from the mold to form a PVDF film.
[0018] S5, cut the PVDF film to a size suitable for attaching to the surface of the slider to obtain an easily accessible electron layer.
[0019] S6. Cut the volatile electron layer material to a size suitable for attachment to the ring structure, and cut it to a size suitable for attachment to the slider, to obtain the volatile electron layer.
[0020] S7. Conductive copper wires are adhered to the volatile electron layer on the inner surface of the sliding groove that contacts the slider and the volatile electron layer on the slider, respectively, using conductive silver paste.
[0021] S8. A layer of volatile electrons is adhered to the slider, and then a layer of readily available electrons is adhered on the volatile electrons layer. A layer of volatile electrons is also adhered to the inner surface of the annular structure that contacts the slider. The slider is connected to the connecting post by a spring. The slider is placed in the sliding groove, the top layer is placed on the bottom layer, and the connection is fixed by the connecting structure and the groove structure to complete the fabrication of the sensor.
[0022] S9 involves attaching insulating material to the outer surfaces of the top and bottom layers to complete the encapsulation.
[0023] Furthermore, the 3D printer parameters in steps S1 and S2 are: nozzle temperature 230°C and heated bed temperature 65°C.
[0024] Furthermore, in step S3, the mixing mass ratio of PVDF to DMF is 1:9.
[0025] The present invention has the following beneficial effects:
[0026] 1. The sensor provided by this invention uses soft and non-toxic materials for its main body, making it safe, comfortable, and lightweight to wear. Due to the self-powered characteristics of the triboelectric nanogenerator, it is even more convenient to wear. The encapsulation uses non-toxic insulating materials, which can avoid the influence of human body surface charge on the sensor.
[0027] 2. The sensor provided by this invention features an independent triboelectric device. A loss-of-electron layer and an gain-of-electron layer are attached to the surface of the slider or the surface of the annular structure in contact with the slider. The triboelectric device is easy to manufacture, allowing the sensor body, which is difficult to manufacture, to be reused repeatedly. This makes the sensor easy to replace and adjust. It shortens the manufacturing cycle, reduces costs, and extends the sensor's lifespan.
[0028] 3. The sensor provided by this invention initially positions the slider near the connecting post on the bottom layer, without contacting the tangential surface of the sliding groove away from the connecting post. Compared to a design that only has a single ring structure within the sliding groove, this design can more accurately reflect the slider's current position, thus reflecting more operational conditions. The sensor provided by this invention allows for free selection of the working direction; it can operate simultaneously in four directions or in one direction alone, thereby adapting to different working environments. Attached Figure Description
[0029] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific 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. In the drawings:
[0030] Figure 1 A top view of the underlying structure of a sensor based on a triboelectric nanogenerator according to the present invention is shown;
[0031] Figure 2 A top view of the top structure of a sensor based on a triboelectric nanogenerator according to the present invention is shown;
[0032] Figure 3 An exploded side cross-sectional view of the overall structure of a sensor based on a triboelectric nanogenerator according to the present invention is shown.
[0033] Figure 4 This image shows a top view of a sensor based on a triboelectric nanogenerator according to the present invention, with the top layer removed.
[0034] The reference numerals in the above figures are as follows:
[0035] 10. Bottom layer; 11. Square protrusion structure; 111. Trapezoidal structure; 12. Connecting column; 121. Connecting structure; 13. Circular groove; 20. Top layer; 21. Groove structure; 30. Slider; 31. Cylinder structure; 32. Quadrangular frustum structure; 40. Spring; 50. Sliding groove. Detailed Implementation
[0036] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.
[0037] like Figure 1 , Figure 2 , Figure 3 and Figure 4 The sensor shown includes a triboelectric nanogenerator and a triboelectric device. The sensor body includes a bottom layer 10 and a top layer 20. The triboelectric device includes a ring structure (not shown in the figure), a slider 30 and a spring 40.
[0038] The top layer 20 covers the bottom layer 10, and there are multiple sliding grooves 50 between the top layer 20 and the bottom layer 10. The slider 30 is located in the sliding groove 50. The side wall of the sliding groove 50 is approximately circular. There are multiple spaced annular grooves 13 on the side wall of the sliding groove 50. The annular grooves 13 are adapted to the shape of the side wall of the sliding groove 50. There is an annular structure in the annular groove 13. The slider 30 has a volatile electron layer and a gain electron layer covering the volatile electron layer. The surface of the annular structure that contacts the slider 30 has a volatile electron layer. The length of the sliding groove 50 is greater than the length of the slider 30. One end of the slider 30 is connected to a spring 40. The spring 40 is fixed to the surface of the bottom layer 10 relative to the top layer 20 by a connecting post 12. Bottom layer 10, top layer 20, slider 30, spring 40, top layer 20, bottom layer 10, slider 30, spring 40, top layer 20, bottom layer 10, top layer 20, bottom layer 10, sliding groove 50, slider 30, sliding groove 50, slider 30, spring 40, spring 40, connecting post 12. Bottom layer 10, top layer 20, slider 30, sliding groove 50, slider 30. During assembly, the annular structure (not shown in the figure) is placed in the annular groove 13, the slider 30 is placed in the sliding groove 50, and the slider 50 is connected to the connecting post 12 at the center of the bottom layer 10 through the spring 40. Finally, the whole is wrapped with the encapsulation layer to complete the assembly.
[0039] The slider is connected to the bottom layer by a spring, allowing it to return to its initial state when no external force is applied. Easily lost and easily gained electron layers are attached to the surface of the slider and the sliding groove in contact with it. The triboelectric device is easy to manufacture, allowing the sensor body, which is difficult to manufacture, to be reused repeatedly, and making the entire sensor easy to replace and adjust. This shortens the manufacturing cycle, reduces costs, and extends the sensor's lifespan.
[0040] Specifically, the bottom layer 10 is a square, and each of the four corners of the bottom layer 10 has a square protrusion structure 11. Each square protrusion structure 11 forms a sliding groove 50 with the adjacent square protrusion structure 11, and multiple sliding grooves 50 form a cross-shaped structure.
[0041] Specifically, the connecting post 12 is located at the center of the bottom layer 10. The end face of the connecting post 12 away from the bottom layer 10 has a raised cross-shaped connecting structure 121. The top layer 20 is the same size and shape as the bottom layer 10. The top layer 20 has a cross-shaped groove structure 21 at its center. The connecting structure 121 and the groove structure 21 cooperate with each other. This allows the slider to slide freely in the sliding groove while ensuring that the slider will not fall out of the sliding groove.
[0042] Specifically, four sliders 30 are located within four sliding grooves 50, and one end of each slider 30 is fixedly connected to one of four springs 40.
[0043] Specifically, the upper part of the slider 30 is a cylindrical structure 31, the lower part is a truncated pyramid structure 32, and the contact point between the square protrusion structure 11 and the slider 30 is a trapezoidal structure 111.
[0044] Specifically, the volatile electron layer is made of copper tape, and the volatile electron layer is made of PVDF or PI; the length of the annular groove is 0.8cm, the distance between the two annular grooves is 0.2cm, and the length of the slider is 1cm.
[0045] Initially, the slider 30 is located near the connecting post 12 on the bottom layer and does not contact the tangential surface of the sliding groove 50 away from the connecting post 12. Compared to a design that only has a single ring structure in the sliding groove 50, this design can more accurately reflect the current position of the slider 30, and thus reflect more working conditions. The sensor provided by this invention can freely select the working direction, can work simultaneously in four directions, or work independently in one direction, thereby adapting to different working environments.
[0046] Specifically, a TPU film is encapsulated on the outer side of the top layer 20 and the bottom layer 10.
[0047] A method for fabricating a sensor based on a triboelectric nanogenerator includes the following steps:
[0048] S1 utilizes 3D printing technology to print the bottom layer 10, top layer 20, and slider 30 according to actual size requirements. Specifically, the top and bottom layers are made of TPU, and their dimensions are both 5cm*5cm*1cm. The TPU material makes the top and bottom layers soft, lightweight, and easy for the human body to wear. 3D printing technology facilitates the fabrication of the sensor body (i.e., the bottom and top layers) and the triboelectric device (i.e., the ring structure and slider), enabling mass production. The dimensions of both the sensor body and the triboelectric device are controllable, improving device performance.
[0049] S2 uses 3D printing technology to print a mold for preparing PVDF films. The mold is a mold without microstructures on its surface.
[0050] S3: Mechanically stir PVDF and DMF (N,N-dimethylformamide) to obtain a PVDF spinning precursor solution; S4: Apply the PVDF spinning precursor solution evenly to a mold using an electrospinning machine, and after constant-temperature drying, peel off the PVDF coating from the mold to form a PVDF film. The coating is completed using electrospinning technology to reduce performance differences caused by the manufacturing process. Specifically, 3 ml of PVDF spinning precursor solution is drawn and loaded into a syringe. A 19G stainless steel flat-tipped needle is used for spinning. The needle is connected to the positive terminal of a high-voltage power supply, and the receiving plate is connected to the negative terminal. The mold is placed on the receiving plate, with a distance of 10 cm between the needle and the receiving plate. Nanofiber membranes are prepared at 12 kV, with a pump push speed of 0.008 mm / s and a horizontal left-right movement speed of 10 mm / s for the syringe. Spinning is carried out at an environment of 26–29℃. After constant-temperature drying of the mold, the PVDF coating is peeled off from the mold to form a PVDF film.
[0051] S5, the PVDF film is cut to a size suitable for attachment on the surface of slider 30 to obtain an easily accessible electron layer.
[0052] S6. The volatile electron layer material is cut into the shape of the inner surface of the sliding groove 50 that contacts the slider 30, and cut to a size suitable for attachment to the slider 30, thus obtaining the volatile electron layer. The volatile electron layer is manufactured using a coating-stripping technique, and microstructures can be added to it to increase the friction area and improve the output voltage and sensitivity. S7. Conductive copper wires are adhered to the volatile electron layer on the inner surface of the sliding groove 50 that contacts the slider 30 and the volatile electron layer on the slider 30 using conductive silver paste.
[0053] S8, a layer of volatile electrons is adhered to the slider 30, and then a layer of volatile electrons is adhered to the volatile electrons layer. A layer of volatile electrons is adhered to the inner surface of the sliding groove 50 that contacts the slider 30. The slider 30 is connected to the connecting post 12 by the spring 40. The slider 30 is placed in the sliding groove 50, the top layer 20 is placed on the bottom layer 10, and they are fixedly connected by the connecting structure 121 and the groove structure 21 to complete the fabrication of the sensor.
[0054] S9, an insulating material is adhered to the outside of the top layer 20 and the bottom layer 10 to complete the encapsulation.
[0055] Specifically, the 3D printer parameters in steps S1 and S2 are: nozzle temperature 230°C and heated bed temperature 65°C.
[0056] Specifically, in step S3, the mixing mass ratio of PVDF to DMF is 1:9.
[0057] Specifically, the electrospinning machine parameters in step S4 are set to a spinning voltage of 12KV.
[0058] Specifically, the conductive copper wire in step S7 is an enameled wire, which is polished only at both ends to avoid environmental interference, and is used to connect the host computer and the sensor body.
[0059] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.
Claims
1. A frictional nanogenerator-based sensor, characterized by, include: The sensor body comprises a bottom layer and a top layer, and the triboelectric device comprises a ring structure, a slider, and a spring. The top layer covers the bottom layer, and there are multiple sliding grooves between the top layer and the bottom layer. The slider is located in the sliding groove. The sidewall of the sliding groove is approximately circular. There are multiple spaced annular grooves on the sidewall of the sliding groove. The annular grooves are adapted to the shape of the sidewall of the sliding groove. The annular grooves contain the annular structure. The slider has a volatile electron layer and a gain electron layer covering the volatile electron layer. The volatile electron layer is on the surface of the annular structure that contacts the slider. The length of the sliding groove is greater than the length of the slider. One end of the slider is connected to the spring. The spring is fixed to the surface of the bottom layer relative to the top layer by a connecting post. The bottom layer is square, and each of the four corners of the bottom layer has a square protrusion structure. Each square protrusion structure forms a sliding groove with the adjacent square protrusion structure, and multiple sliding grooves form a cross shape. The four sliders are respectively located in the four sliding grooves, and one end of each of the four sliders is fixedly connected to the four springs.
2. The sensor based on a triboelectric nanogenerator according to claim 1, characterized in that, The connecting post is located at the center of the bottom layer. The end face of the connecting post away from the bottom layer has a raised "+" shaped connecting structure. The top layer and the bottom layer are the same size and shape. The top layer has a "+" shaped groove structure at its center. The connecting structure and the groove structure cooperate with each other.
3. The sensor based on a triboelectric nanogenerator according to claim 1, characterized in that, The upper part of the slider is a cylindrical structure, the lower part is a truncated pyramid structure, and the part of the square protrusion that contacts the slider is a trapezoidal structure.
4. A sensor based on a triboelectric nanogenerator according to claim 1, characterized in that, The volatile electron layer is made of copper tape, and the volatile electron layer is made of PVDF or PI; the length of the annular groove is 0.8 cm, the distance between two annular grooves is 0.2 cm, and the length of the slider is 1 cm.
5. A sensor based on a triboelectric nanogenerator according to claim 1, characterized in that, The outer sides of the top layer and the bottom layer are encapsulated with a TPU film.
6. A method for fabricating a sensor based on a triboelectric nanogenerator as described in any one of claims 1-5, characterized in that, Specifically, the steps include the following: S1 utilizes 3D printing technology and prints the bottom layer, top layer, ring structure, and slider according to actual size requirements; S2, using 3D printing technology, prints molds for preparing PVDF films; S3, mechanically stir PVDF and DMF to obtain PVDF spinning precursor solution; S4. The PVDF spinning precursor solution is evenly coated onto the mold using an electrospinning machine. After drying at a constant temperature, the PVDF coating is peeled off from the mold to form a PVDF film. S5, cut the PVDF film to a size suitable for attaching to the surface of the slider to obtain an easily accessible electron layer; S6. Cut the volatile electron layer material to a size suitable for attachment to the ring structure, and cut it to a size suitable for attachment to the slider to obtain the volatile electron layer. S7, conductive copper wires are adhered to the volatile electron layer on the inner surface of the sliding groove in contact with the slider and the volatile electron layer on the slider, respectively, using conductive silver paste. S8, a layer of volatile electrons is adhered to the slider, and then a layer of readily available electrons is adhered to the volatile electrons layer. A layer of volatile electrons is adhered to the inner surface of the annular structure that contacts the slider. The slider is connected to the connecting post by a spring. The slider is placed in the sliding groove, the top layer is placed on the bottom layer, and the connection is fixed by the connecting structure and the groove structure to complete the fabrication of the sensor. S9 involves attaching insulating material to the outer surfaces of the top and bottom layers to complete the encapsulation.
7. The method for fabricating a sensor based on a triboelectric nanogenerator according to claim 6, characterized in that, The 3D printer parameters in steps S1 and S2 are: nozzle temperature 230℃ and heated bed temperature 65℃.
8. The method for fabricating a sensor based on a triboelectric nanogenerator according to claim 6, characterized in that, In step S3, the mixing mass ratio of PVDF to DMF is 1:9.