Broadband wide piezoresistive sensing structure simulating scorpion threshold response characteristic

Abstract

The utility model relates to the technical field of bionic pressure sensors, in particular to a broadband wide piezoresistive sensing structure simulating scorpion threshold response characteristics, which comprises a threshold adjusting structure and a piezoresistive sensing unit. The threshold value adjusting structure comprises a flexible deformation cover and a threshold value sensing structure base, the flexible deformation cover covers the top end of the threshold value sensing structure base, the piezoresistive sensing unit is arranged in the threshold value sensing structure base, and a rectangular through groove is formed in the bottom of the threshold value sensing structure base; a threading hole is formed in the side wall of the threshold sensing structure base; the flexible deformation cover comprises a sheet, and the center of the lower surface of the sheet is integrally connected with an inverted-cone-shaped protruding block. The problems that the inherent contradiction exists between the sensitivity and the bandwidth performance of an existing piezoresistive sensor, in particular, structural instability under large signals is easily caused when the sensitivity is improved through a traditional design, and the response capacity to small signals is greatly reduced by increasing rigid support to expand the measuring range are solved.

Description

Technical Field

[0001] This utility model relates to the field of biomimetic pressure sensor technology, specifically a wide-bandwidth piezoresistive sensing structure that mimics the threshold response characteristics of a scorpion. Background Technology

[0002] In the field of modern sensor technology, piezoresistive sensors typically employ a homogeneous sensitive layer and a single sensing unit structure, detecting pressure or strain signals through changes in the resistance of the piezoresistive material. These sensors play a crucial role in fields such as medical monitoring and industrial inspection. Their core design goal is to improve sensitivity to capture weak signals or to extend the measurement range to meet the needs of detecting high-intensity signals.

[0003] However, existing piezoresistive sensors have an inherent contradiction in terms of sensitivity and bandwidth performance: although sensors with thin flexible structures can improve sensitivity, they are prone to structural instability under large signals due to stress concentration; while wide-range designs that thicken the substrate or add rigid support will significantly reduce the response capability to small signals.

[0004] Therefore, it is necessary to invent a wide-bandwidth piezoresistive sensing structure that mimics the threshold response characteristics of a scorpion to solve the above problems. Utility Model Content

[0005] To address the inherent contradiction between sensitivity and bandwidth performance in existing piezoresistive sensors, particularly the problem that traditional designs can easily lead to structural instability under large signals while improving sensitivity, and that increasing rigid support to extend the measurement range can significantly reduce the response capability to small signals, this invention provides a wide-bandwidth piezoresistive sensing structure with scorpion-like threshold response characteristics.

[0006] This utility model is achieved using the following technical solution:

[0007] A wide-bandwidth piezoresistive sensing structure with scorpion-like threshold response characteristics includes a threshold adjustment structure and a piezoresistive sensing unit.

[0008] The threshold adjustment structure includes a flexible deformable cover and a threshold sensing structure base. The flexible deformable cover is placed on the top of the threshold sensing structure base, and the piezoresistive sensing unit is placed inside the threshold sensing structure base. A rectangular through groove is opened at the bottom of the threshold sensing structure base, and a wire hole is opened on the side wall of the threshold sensing structure base.

[0009] The flexible deformable cover includes a thin sheet, and an inverted conical protrusion is integrally connected to the center of the lower surface of the thin sheet;

[0010] The piezoresistive sensing unit includes a flexible substrate film, and a conductive paste layer is disposed on the upper surface of the flexible substrate film. The conductive paste layer includes several parallel strip-shaped piezoelectric sensing units.

[0011] Furthermore, the sheet is circular, and the thickness of the sheet ranges from 0.1 mm to 0.2 mm.

[0012] Furthermore, the threshold sensing structure base is in the shape of a circular bottle cap, and the piezoresistive sensing unit is fixed to the inner bottom wall of the threshold sensing structure base and covers the rectangular through groove.

[0013] Furthermore, the flexible substrate film is made of one of paper, polyethylene terephthalate film, or polyimide film, and the thickness of the flexible substrate film ranges from 0.1 mm to 0.2 mm.

[0014] Furthermore, the threshold sensing structure base is made of resin material.

[0015] This invention features a reasonable and reliable structural design. The piezoresistive sensing unit mimics the strain amplification structure in the scorpion slit receptor. A conductive paste layer on the surface of the flexible substrate film includes several parallel strip-shaped piezoelectric sensing units, simulating the rigid regions on both sides of the scorpion slit and the flexible crack region in the middle. This "hard-soft-hard" structure of the biological surface sensor slit can generate significant resistance changes under minute strains, thereby improving the sensor's ability to identify weak signals and enhancing sensitivity. This overcomes the problem of insensitivity to small signals caused by the simple structure and uniform materials of traditional piezoresistive sensors. Furthermore, by changing one or more of the following three parameters—the height of the threshold sensing structure base, the height of the conical protrusion, and the elastic modulus of the flexible deformable cover—the threshold value of this scorpion-inspired wide-bandwidth piezoresistive sensing structure can be altered. This adjusts the response range of this scorpion-inspired wide-bandwidth piezoresistive sensing structure to different pressures / strains, solving the problem of fixed response thresholds in traditional sensors that cannot adapt to different intensity excitations. This allows the sensor to selectively respond according to the intensity of external stimuli, avoiding overload distortion or missed detection of small signals. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0017] Figure 2 This is a front view of the present invention.

[0018] Figure 3 It is along Figure 2 A cross-sectional view along line AA in the middle.

[0019] Figure 4 This is the resistance-force output response diagram of the wide bandwidth piezoresistive sensing structure in Embodiment 1 of this utility model.

[0020] Figure 5This is a schematic diagram of the deformation mechanism of the wide bandwidth piezoresistive sensing structure in Embodiment 1 of this utility model when it does not perform the threshold adjustment function.

[0021] Figure 6 This is a schematic diagram of the deformation mechanism of the wide bandwidth piezoresistive sensing structure in Embodiment 1 of this utility model when it performs the threshold adjustment function.

[0022] Figure 7 This is a comparison diagram of the resistance-force output response of the wide-bandwidth piezoresistive sensing structure in Embodiment 1, the wide-bandwidth piezoresistive sensing structure in Embodiment 2, and the strain sensor with a thresholdless structure.

[0023] Figure 8 This is a schematic diagram of the piezoresistive sensing unit in this utility model.

[0024] In the figure: 1. Piezoresistive sensing unit; 2. Flexible deformable cover; 3. Threshold sensing structure base; 4. Rectangular through groove; 5. Wire hole; 6. Flexible substrate film; 7. Conductive paste layer. Detailed Implementation

[0025] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model. Example 1

[0026] A wide-bandwidth piezoresistive sensing structure mimicking scorpion threshold response characteristics, as shown in the attached figure. Figure 1 ~Appendix Figure 3 Appendix Figure 8 As shown, it includes a threshold adjustment structure and a piezoresistive sensing unit 1;

[0027] The threshold adjustment structure includes a flexible deformable cover 2 and a threshold sensing structure base 3. The flexible deformable cover 2 includes a circular sheet with a diameter of 8 mm and a thickness of 0.1 mm. An inverted conical protrusion is integrally connected to the center of the lower surface of the circular sheet. The diameter of the largest circular cross-section of the inverted conical protrusion is 0.5 mm, and the height of the inverted conical protrusion is 0.5 mm. The flexible deformable cover 2 is placed on the top of the threshold sensing structure base 3, and the piezoresistive sensing unit 1 is disposed inside the threshold sensing structure base 3. The threshold sensing structure base 3 is made of resin material, and a rectangular through groove 4 with a length of 10 mm, a width of 4 mm, and a depth of 1.5 mm is opened at the bottom of the threshold sensing structure base 3. The threshold sensing structure base 3 is shaped like a circular bottle cap, with a diameter of 8 mm and a height of 3.5 mm. A pair of opposing diameters of 0.5 mm are opened on the side wall of the threshold sensing structure base 3. The piezoresistive sensing unit 1 is fixed to the inner bottom wall of the threshold sensing structure base 3 and covers the rectangular through groove 4. The piezoresistive sensing unit 1 has a length of 12 mm, a width of 5 mm, and a thickness of 0.2 mm.

[0028] The piezoresistive sensing unit 1 includes a flexible substrate film 6, and a conductive paste layer 7 is disposed on the upper surface of the flexible substrate film 6. The conductive paste layer 7 includes a plurality of parallel strip-shaped piezoelectric sensing units. The flexible substrate film 6 is made of glossy photo paper with a thickness of 0.2 mm.

[0029] The threshold value of the wide-bandwidth piezoresistive sensing structure with the simulated scorpion threshold response characteristics was measured to be 1.8N using a multimeter and a tension / compression gauge.

[0030] As attached Figure 4 ~Appendix Figure 6 As shown, the resistance-force output response curve of the wide-bandwidth piezoresistive sensing structure with scorpion-like threshold response characteristics in this embodiment shows a significant change starting from a force of 1.8N. This indicates that before reaching this force value, the resistance of the wide-bandwidth piezoresistive sensing structure changes very little or almost nothing. When the force exceeds 1.8N, the curve rises rapidly, showing that the wide-bandwidth piezoresistive sensing structure is very sensitive to changes in force after this point. This design helps to avoid the sensor reacting to small disturbance forces below a certain threshold, improving the stability and reliability of the sensor in specific application scenarios. Example 2

[0031] The difference between this embodiment and embodiment 1 is that the height of the threshold sensing structure base 3 of the wide bandwidth piezoresistive sensing structure with scorpion-like threshold response characteristics in this embodiment is 4 mm, while the rest of the structure is the same as in embodiment 1.

[0032] Using a multimeter and a tension / compression gauge, the threshold value of the wide-bandwidth piezoresistive sensing structure with scorpion-like threshold response characteristics in this embodiment was measured to be 2.3N.

[0033] As attached Figure 7 As shown, the resistance-force output response curve of the wide-bandwidth piezoresistive sensing structure with scorpion-like threshold response characteristics in this embodiment is compared with the resistance-force output response curve of the wide-bandwidth piezoresistive sensing structure with scorpion-like threshold response characteristics in Embodiment 1 and the resistance-force output response curve of the strain sensor without threshold structure. It can be seen that the resistance-force output response curve of the strain sensor without threshold structure starts from the origin (0,0), and the resistance change rate (ΔR / R) gradually increases with the increase of force, showing the direct response characteristics of the strain sensor without threshold structure to force; the resistance-force output response curve of the wide-bandwidth piezoresistive sensing structure with scorpion-like threshold response characteristics obtained in Embodiment 1 starts from a force of 1.8N. The obvious change indicates that before reaching this force value, the resistance of the wide-bandwidth piezoresistive sensing structure changes very little or almost nothing. When the force exceeds 1.8N, the curve rises rapidly, showing that the wide-bandwidth piezoresistive sensing structure of Example 1 is very sensitive to changes in force thereafter. In contrast, the resistance-force output response curve of the wide-bandwidth piezoresistive sensing structure with scorpion threshold response characteristics in this embodiment shows a significant change starting from a force of 2.3N, indicating that before reaching this force value, the resistance of the wide-bandwidth piezoresistive sensing structure changes very little or almost nothing. When the force exceeds 2.3N, the curve rises rapidly, showing that the wide-bandwidth piezoresistive sensing structure of this embodiment is very sensitive to changes in force thereafter.

[0034] It should be noted that the strain sensor without a threshold structure in this embodiment uses a graphene-based flexible sensor, but is not limited to this type of sensor. Such sensors usually do not have a preset threshold, but their actual response may have a slight baseline shift due to material properties or structural design.

[0035] In the specific implementation of this utility model, the threshold sensing structure base 3 can be made of Somos®LEDO6060 resin material, but is not limited to this type of resin material; this utility model can change the threshold value of the wide bandwidth piezoresistive sensing structure with scorpion-like threshold response characteristics by changing one or more of the following three data: the height of the threshold sensing structure base 3, the height of the conical protrusion, and the elastic modulus of the flexible deformable cover 2, that is, adjust the response range of the wide bandwidth piezoresistive sensing structure with scorpion-like threshold response characteristics to different pressures / strains.

[0036] In the description of this utility model, it should be understood that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this utility model and simplifying the description, and is not intended to 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 this utility model.

[0037] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A wide bandwidth piezoresistive sensing structure emulating the scorpion tail threshold response characteristic, characterized by: Including a threshold adjustment structure and a piezoresistive sensing unit (1); The threshold adjustment structure includes a flexible deformable cover (2) and a threshold sensing structure base (3). The flexible deformable cover (2) is placed on the top of the threshold sensing structure base (3), and the piezoresistive sensing unit (1) is placed inside the threshold sensing structure base (3). A rectangular through groove (4) is opened at the bottom of the threshold sensing structure base (3), and a wire hole (5) is opened on the side wall of the threshold sensing structure base (3). The flexible deformable cover (2) includes a thin sheet, and an inverted conical protrusion is integrally connected to the center of the lower surface of the thin sheet; The piezoresistive sensing unit (1) includes a flexible substrate film (6), and a conductive paste layer (7) is disposed on the upper surface of the flexible substrate film (6). The conductive paste layer (7) includes several parallel strip-shaped piezoelectric sensing units.

2. The wide bandwidth piezoresistive sensing structure with scorpion-like threshold response characteristics according to claim 1, characterized in that: The sheet is circular and has a thickness ranging from 0.1 mm to 0.2 mm.

3. The wide bandwidth piezoresistive sensing structure emulating the scorpion's threshold response characteristic according to claim 1, characterized in that: The threshold sensing structure base (3) is in the shape of a circular bottle cap, and the piezoresistive sensing unit (1) is fixed to the inner bottom wall of the threshold sensing structure base (3) and covers the rectangular through groove (4).

4. The wide bandwidth piezoresistive sensing structure emulating the scorpion's threshold response characteristic according to claim 1, characterized in that: The flexible substrate film (6) is made of one of paper, polyethylene terephthalate film, or polyimide film, and the thickness of the flexible substrate film (6) is in the range of 0.1 mm to 0.2 mm.

5. The wide bandwidth piezoresistive sensing structure emulating the scorpion's threshold response characteristic according to claim 1, characterized in that: The threshold sensing structure base (3) is made of resin material.

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