A pressure sensing device based on strain bridge and piezoresistance fusion and a detection method

Abstract

The application discloses a kind of pressure sensing device and detection method based on strain bridge and piezoresistive fusion, belong to pressure measurement technical field, including the elastic layer, piezoresistive sensing unit and substrate sequentially arranged along vertical direction;Wherein, piezoresistive sensing unit is multiple, and multiple piezoresistive sensing unit is distributed on substrate surface;Piezoresistive sensing unit is provided with force plate on the side away from substrate, and at least two needles are protruded on the side of force plate towards substrate, and the end of two needles away from force plate is abutted with strain bridge measurement unit, and two needles are respectively abutted at the pressure loading surface of strain bridge measurement unit.The pressure originally dispersed to the whole substrate surface is concentrated in force plate in the application, and finally concentrated and transmitted to needle on force plate, realize the concentrated output of pressure, and the pressure direction measured by piezoresistive sensing unit and the pressure size measured by strain bridge measurement unit are fused, to realize the accurate measurement of pressure size and pressure position.

Description

Technical Field

[0001] This invention belongs to the field of pressure measurement technology, specifically relating to a pressure sensing device and detection method based on the fusion of strain gauge bridge and piezoresistive pressure. Background Technology

[0002] With the rapid advancement of intelligent robot technology, research on robot tactile sensing technology is also flourishing. Flexible tactile sensors have wide applications in feedback control in unstructured environments and collision safety detection. These sensors possess softness and flexibility similar to human skin, enabling them to adapt to changes in the external environment under different curvatures and pressures, and to quickly and accurately acquire external information.

[0003] Currently, the main solution for flexible tactile sensors is the piezoresistive sensor. This sensor uses a piezoresistive array structure to sense the location and magnitude of pressure. It utilizes the property that the resistance of a material changes accordingly when it deforms under pressure, converting pressure into a measurable and readable electrical signal. When the piezoresistive sensor deforms under pressure, the conductive circuitry within the internal piezoresistive structure becomes compressed and denser, causing a rapid change in resistance. When the external pressure is removed, the circuitry within the internal piezoresistive structure disengages, and the resistance returns to its initial level, thus achieving pressure measurement.

[0004] Due to the inherent physical properties of piezoresistive materials, their resistance-pressure relationship is exponential, and they exhibit significant hysteresis (the curves are inconsistent during loading and unloading) and creep (the resistance continues to change while the pressure remains constant). Furthermore, when there are multiple piezoresistive units on the sensor, crosstalk exists between the units, making it impossible to simply convert the final signal into a Newton value. As a result, existing piezoresistive sensors still have many drawbacks in the accurate measurement of force. Summary of the Invention

[0005] In view of one or more of the above-mentioned defects or improvement needs of the prior art, the present invention provides a pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure to solve the problem that existing piezoresistive sensors cannot achieve accurate pressure measurement.

[0006] To achieve the above objectives, the present invention provides a pressure sensing device based on the fusion of strain bridge and piezoresistive sensing, comprising an elastic layer, a piezoresistive sensing unit and a substrate arranged sequentially along the vertical direction. The piezoresistive sensing unit is a plurality of units, and the plurality of piezoresistive sensing units are distributed on the surface of the substrate; The piezoresistive sensing unit has a force plate on the side away from the substrate. At least two pins extend from the force plate toward the substrate. The ends of the two pins away from the force plate abut against a strain bridge measuring unit. The two pins abut against the pressure loading surface of the strain bridge measuring unit.

[0007] As a further improvement of the present invention, the force plate extends four pins toward the substrate, and the end of the pins away from the force plate abuts against two sets of strain bridge measurement units. The four pins abut against the pressure loading surfaces of the two sets of strain bridge measurement units respectively.

[0008] As a further improvement of the present invention, a deformation beam is provided at one end of the ejector pin facing the strain bridge measurement unit. The deformation beam is made of elastic material and has an "I"-shaped structure. Two sets of strain bridge measurement units are respectively attached to the side of the deformation beam away from the ejector pin, and both strain bridge measurement units have a strip-shaped structure. The two strain bridge measurement units are respectively attached to the beam structure surface of the deformation beam.

[0009] As a further improvement of the present invention, the two strain bridge measurement units are connected by a conductive thin film, and the conductive thin film is electrically connected to the substrate.

[0010] As a further improvement of the present invention, a first through hole is correspondingly opened on the substrate, the force plate is attached to the surface of the substrate, and the ejector pin passes through the first through hole and abuts against the strain bridge measurement unit.

[0011] As a further improvement of the present invention, a fixing plate is also connected to the side of the deformable beam facing the substrate, and the fixing plate is fixedly connected to the substrate; a second through hole is provided on the fixing plate, and the ejector pin passes through the second through hole and abuts against the deformable beam.

[0012] As a further improvement of the present invention, the deformable beam is provided with a plurality of crimping grooves on the side facing the ejector pin, and the end of the ejector pin facing the deformable beam abuts against the crimping groove.

[0013] As a further improvement of the present invention, a plurality of the piezoresistive sensing units are arranged in an array on the surface of the substrate.

[0014] As a further improvement of the present invention, it also includes a mounting housing, one end of which is open, and the elastic layer is provided at the opening. The elastic layer and the mounting housing form a closed space, and the piezoresistive sensing unit, the substrate, the force plate and the strain bridge measuring unit are all disposed within the closed space formed by the elastic layer and the mounting housing.

[0015] The present invention also includes a pressure detection method based on the fusion of strain gauge bridge and piezoresistive pressure sensing, which performs detection using the pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure sensing, and includes the following steps: S1. The piezoresistive sensing unit senses pressure, and the pressure sensing position is determined based on the position of the piezoresistive sensing unit on the substrate surface. S2, the strain gauge bridge measurement unit senses the pressure magnitude; S3. The pressure location and magnitude are obtained by fusing the pressure sensing position obtained by the piezoresistive sensing unit and the pressure magnitude sensed by the strain gauge bridge measurement unit.

[0016] The aforementioned improved technical features can be combined with each other as long as they do not conflict with each other.

[0017] In summary, the beneficial effects of the above-described technical solutions conceived by this invention compared with the prior art include: (1) The pressure sensing device based on the fusion of strain bridge and piezoresistive sensing of the present invention combines the piezoresistive sensing unit with the strain bridge measurement unit, arranges multiple piezoresistive sensing units in a distributed manner, and utilizes the large force sensing surface of the piezoresistive sensing unit to realize all-round detection of the force on the substrate surface, so as to accurately know the position of the force point of the pressure sensing device; in addition, the present invention sets a force plate and a pin structure in the pressure sensing device, concentrates the pressure that was originally dispersed on the entire substrate surface to the force plate, and finally transmits it to the pin through the force plate to realize the concentrated output of pressure. Finally, the pressure is accurately measured by the strain bridge measurement unit that is sensitive to the pressure at the endpoint. By fusing the pressure orientation measured by the piezoresistive sensing unit with the pressure magnitude measured by the strain bridge measurement unit, the accurate measurement of pressure magnitude and pressure position is realized.

[0018] (2) The pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure of the present invention uses two sets of strain gauge bridge measurement units to form a rectangular measurement point. When the pressure sensing device is subjected to force, the pressure is distributed to the force plate, and the force plate transmits the pressure to the pressure loading surfaces of the two sets of strain gauge bridge measurement units through four pins, thus realizing accurate pressure measurement. In addition, the two sets of strain gauge bridge measurement units can form a differential measurement system. By differentially processing the pressure data of the two sets of strain gauge bridge measurement units, common-mode interference caused by the external environment (temperature, humidity) can be effectively eliminated, improving the signal-to-noise ratio and measurement stability.

[0019] (3) The pressure sensing device based on the fusion of strain bridge and piezoresistive pressure of the present invention sets a deformation beam between the ejector pin and the strain bridge measuring unit. The deformation beam is an "I" structure, which is similar in shape to the two sets of strain bridge measuring units. When the ejector pin pressure is applied to the deformation beam, the stress point of the deformation beam deforms accordingly and transmits the lattice pressure to the pressure loading surface of the strain bridge measuring unit, thereby realizing accurate pressure measurement. Attached Figure Description

[0020] Figure 1 This is an exploded structural diagram of a pressure sensing device based on the fusion of strain bridge and piezoresistive technology in an embodiment of the present invention. Figure 2 This is a schematic diagram of the overall structure of the pressure sensing device based on the fusion of strain bridge and piezoresistive technology in an embodiment of the present invention. Figure 3 This is a schematic diagram of the structure at the point where the ejector pin abuts against the deformed beam in an embodiment of the present invention; Figure 4 This is a schematic diagram of the piezoresistive sensing unit arranged on the substrate surface in an embodiment of the present invention; Figure 5 This is a schematic diagram of the strain gauge bridge measurement unit structure in an embodiment of the present invention; Figure 6 This is a schematic flowchart of the pressure detection method based on the fusion of strain bridge and piezoresistive method in an embodiment of the present invention.

[0021] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1. Elastic layer; 2. Piezoresistive sensing unit; 3. Substrate; 4. Force plate; 5. Ejector pin; 6. Strain gauge bridge measurement unit; 7. Deformation beam; 8. Fixing plate; 9. Mounting housing. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0023] In the description of this invention, it should be understood that, unless otherwise stated, the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are 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. Therefore, they should not be construed as limiting this invention.

[0024] Furthermore, unless otherwise stated, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0025] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0026] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0027] Example: Please see Figures 1-5 The pressure sensing device based on the fusion of strain bridge and piezoresistive sensing in a preferred embodiment of the present invention includes an elastic layer 1, a piezoresistive sensing unit 2 and a substrate 3 arranged vertically in sequence; wherein, there are multiple piezoresistive sensing units 2, and the multiple piezoresistive sensing units 2 are distributed on the surface of the substrate 3; a force plate 4 is provided on the side of the piezoresistive sensing unit 2 away from the substrate 3, and at least two pins 5 extend from the side of the force plate 4 toward the substrate 3, and the ends of the two pins 5 away from the force plate 4 abut against the strain bridge measuring unit 6, and the two pins 5 abut against the pressure loading surface of the strain bridge measuring unit 6 respectively.

[0028] The pressure sensing device based on the fusion of strain gauge bridge and piezoresistive sensing in this invention combines a piezoresistive sensing unit 2 with a strain gauge bridge measurement unit 6. Multiple piezoresistive sensing units 2 are distributed and utilized to achieve omnidirectional detection of the force on the surface of the substrate 3 by leveraging the large force-sensing surface of the piezoresistive sensing unit 2, thus accurately determining the location of the force point of the pressure sensing device. Furthermore, by incorporating a force plate 4 and a push pin 5 structure within the pressure sensing device, the pressure originally dispersed across the entire surface of the substrate 3 is concentrated on the force plate 4 and then transmitted to the push pin 5, achieving a concentrated pressure output. Finally, the pressure is accurately measured by the strain gauge bridge measurement unit 6, which is sensitive to the pressure at the endpoints. By fusing the pressure orientation measured by the piezoresistive sensing unit 2 with the pressure magnitude measured by the strain gauge bridge measurement unit 6, accurate measurement of both pressure magnitude and location is achieved.

[0029] Optionally, in this invention, the pressure loading surface of the strain bridge measurement unit 6 refers to the surface of the elastic body corresponding to the resistance in the strain bridge measurement unit 6. By applying pressure to the pressure loading surface of the strain bridge measurement unit 6, the strain bridge measurement unit 6 generates a corresponding change in electrical signal, thereby achieving accurate pressure sensing.

[0030] Optionally, such as Figure 5 As shown, the strain gauge bridge measurement unit 6 in this invention includes four resistors R1, R2, R3, and R4 arranged side by side. The four resistors are connected end to end to form a closed loop, which together constitutes a Wheatstone bridge structure.

[0031] Furthermore, such as Figure 3 As shown in the preferred embodiment of the present invention, four pins 5 extend from the force-bearing plate 4 towards the substrate 3. Two sets of strain gauge bridge measurement units 6 are attached to the ends of the pins 5 away from the force-bearing plate 4. The four pins 5 are respectively attached to the pressure loading surfaces of the two sets of strain gauge bridge measurement units 6. A single strain gauge bridge measurement unit 6 can only form a linear pressure measurement structure. When the pressure deviates from the center of the substrate 3 and is far from the strain gauge bridge measurement unit 6, it is easy to cause pressure detection deviation of the strain gauge bridge measurement unit 6. The present invention uses two sets of strain gauge bridge measurement units 6, which form a rectangular measurement point. When the pressure sensing device is subjected to force, the pressure is distributed to the force-bearing plate 4, and the force-bearing plate 4 transmits the pressure to the pressure loading surfaces of the two sets of strain gauge bridge measurement units 6 through the four pins 5, thus achieving accurate pressure measurement. In addition, the two sets of strain gauge bridge measurement units 6 can form a differential measurement system. By differentially processing the pressure data of the two sets of strain gauge bridge measurement units 6, common-mode interference caused by the external environment (temperature, humidity) can be effectively eliminated, thereby improving the signal-to-noise ratio and measurement stability.

[0032] Furthermore, as an optional embodiment of the present invention, a deformation beam 7 is also provided at the end of the ejector pin 5 facing the strain bridge measuring unit 6. The deformation beam 7 is made of elastic material and has an "I"-shaped structure. Two sets of strain bridge measuring units 6 are respectively attached to the side of the deformation beam 7 away from the ejector pin 5. Both strain bridge measuring units 6 have a strip-shaped structure and are respectively attached to the surface of the beam structure of the deformation beam 7. The strain bridge measuring unit 6 is similar to the piezoresistive sensing unit 2, both of which are flexible structures. When the ejector pin 5 directly acts on the strain bridge measuring unit 6, the strain bridge measuring unit 6 is easily deformed and displaced under the action of the ejector pin 5. Moreover, the direct action of the ejector pin 5 on the strain bridge measuring unit 6 can easily cause wear on the surface of the strain bridge measuring unit 6, resulting in damage to the strain bridge measuring unit 6. Based on this, the present invention sets a deformation beam 7 between the ejector pin 5 and the strain bridge measurement unit 6. The deformation beam 7 has an overall "I" structure, which is similar in shape to the two sets of strain bridge measurement units 6. When the ejector pin 5 applies pressure to the deformation beam 7, the stress point of the deformation beam 7 deforms accordingly and transmits the lattice pressure to the pressure loading surface of the strain bridge measurement unit 6, thereby realizing accurate pressure measurement.

[0033] Further, as an optional embodiment of the present invention, the two strain gauge bridge measurement units 6 are connected by a conductive film, and the conductive film is electrically connected to the substrate 3. The substrate 3 in the present invention is a PCB board, which is connected to the piezoresistive sensing unit 2 and the strain gauge bridge measurement unit 6 to collect their pressure signals and pressure positions, thereby achieving accurate pressure measurement. The piezoresistive sensing unit 2 is directly attached to the substrate 3, and the two can be directly connected by wires or solder points; while a pin 5 and a deformation beam 7 are also provided between the substrate 3 and the strain gauge bridge measurement unit 6, and a pressing space for the pin 5 needs to be reserved between the substrate 3 and the strain gauge bridge. Based on this, the present invention uses a conductive film to point-connect the strain gauge bridge measurement unit 6 and the substrate 3 to achieve electrical signal transmission between them. The substrate 3 in the present invention integrates a control unit, which can analyze the data collected by the piezoresistive sensing unit 2 and the strain gauge bridge measurement unit 6 to obtain the magnitude and direction of the pressure.

[0034] Further, as an optional embodiment of the present invention, a first through hole is correspondingly formed on the substrate 3, a force-bearing plate 4 is attached to the surface of the substrate 3, and a pin 5 passes through the first through hole and abuts against the strain bridge measurement unit 6. The force-bearing plate 4 is disposed on the side of the substrate 3 facing the elastic layer 1, so that the pressure on the elastic layer 1 can be accurately transmitted to the force-bearing plate 4, which facilitates the improvement of the measurement accuracy of the strain bridge measurement unit 6. In order to control the overall size of the pressure sensing device, the width of the force-bearing plate 4 is similar to the width of the substrate 3. By forming a first through hole on the substrate 3, the pin 5 is positioned away from the substrate 3, which facilitates the pin 5 to transmit pressure to the strain bridge measurement unit 6 on the side of the substrate 3 away from the force-bearing plate 4. On the other hand, the substrate 3 is used to arrange circuits and electronic components. In order to reduce the influence of the first through hole on the circuits and electronic components on the substrate 3, the first through hole is formed on the side of the substrate 3, reducing the area occupied by the first through hole on the substrate 3. Optionally, in this invention, the first through hole on the substrate 3 is a semi-hole structure. The substrate 3 can be limited by the combination structure of the force plate 4 and the ejector pin 5, which facilitates the assembly of the substrate 3 and the force plate 4 and ensures the stable setting of each electronic component in the pressure sensing device.

[0035] Furthermore, as an optional embodiment of the present invention, the deformation beam 7 facing the substrate 3 is also connected to a fixing piece 8, which is fixedly connected to the substrate 3; the fixing piece 8 has a second through hole, and the ejector pin 5 passes through the second through hole and abuts against the deformation beam 7. The pressure sensing device in the present invention is an integral structure. To ensure the stable transmission of force from the elastic layer 1 to the strain bridge measurement unit 6, the present invention provides a fixing piece 8 on the side of the deformation beam 7 facing the substrate 3, and the fixing piece 8 is fixedly connected to the substrate 3, thereby achieving a stable connection between the deformation beam 7 and the substrate 3.

[0036] In this invention, the fixing plate 8 and the deformation beam 7 are preferably bonded together, and the fixing plate 8 and the substrate 3 are preferably bolted together. Optionally, the strain bridge measurement unit 6 is bonded to the surface of the deformation beam 7.

[0037] Furthermore, as an optional embodiment of the present invention, the deformable beam 7 is provided with multiple pressing grooves on the side facing the ejector pin 5, and the end of the ejector pin 5 facing the deformable beam 7 abuts against the pressing groove. The deformable beam 7 is a flexible structure; when the ejector pin 5 abuts against the deformable beam 7, the deformable beam 7 is prone to deformation, causing the abutment position of the ejector pin 5 to shift, and the pressure of the ejector pin 5 cannot be stably transmitted to the pressure loading surface of the strain gauge measurement unit 6. Based on this, the present invention provides corresponding pressing grooves on the deformable beam 7 to limit the abutment position of the ejector pin 5 and ensure that the pressure received by the ejector pin 5 is stably transmitted to the pressure loading surface of the strain gauge measurement unit 6.

[0038] Furthermore, such as Figure 4As shown, in an optional embodiment of the present invention, multiple piezoresistive sensing units 2 are arranged in an array on the surface of the substrate 3. By setting multiple piezoresistive sensing units 2 on the surface of the substrate 3, the present invention senses pressure through piezoresistive sensing units 2 located at different positions, achieving accurate identification of the pressure application position. To facilitate the calculation of the pressure application position by the control unit in the substrate 3, the piezoresistive sensing units 2 are arranged in a regular array on the surface of the substrate 3, facilitating the accurate conversion of the pressure application position to a set coordinate system, thus achieving the identification of the pressure application position. Optionally, the piezoresistive sensing units 2 in the present invention are arranged in a circular array or a square array on the surface of the substrate 3.

[0039] Further, as an optional embodiment of the present invention, the present invention also includes a mounting housing 9, one end of which is open, and an elastic layer 1 is provided at the opening, and the elastic layer 1 and the mounting housing 9 form a closed space; the aforementioned piezoresistive sensing unit 2, substrate 3, force plate 4, and strain bridge measuring unit 6 are all disposed within the closed space formed by the elastic layer 1 and the mounting housing 9. The mounting housing 9 is used to encapsulate the various structures in the pressure sensing device, so that the pressure sensing device is formed into an integral structure. Preferably, the elastic layer 1 and the mounting housing 9 are respectively provided with screws and threaded holes, and the two are threadedly connected as one unit. At the same time, the substrate 3, deformation beam 7, and strain bridge measuring unit 6 are respectively provided with threaded holes, and the substrate 3, deformation beam 7, and strain bridge are connected to the mounting housing 9 by screw structure.

[0040] Furthermore, such as Figure 6 As shown, the present invention also includes a pressure detection method based on the fusion of strain gauge bridge and piezoresistive array, which is implemented by the aforementioned pressure sensing device based on the fusion of strain gauge bridge and piezoresistive array, and includes the following steps: S1. The piezoresistive sensing unit 2 senses the pressure, and the pressure sensing position is determined based on the arrangement position of the piezoresistive sensing unit 2 on the surface of the substrate 3. S2, Strain gauge bridge measurement unit 6 senses the pressure magnitude; S3. The pressure location and magnitude are obtained by fusing the pressure sensing position obtained by the piezoresistive sensing unit 2 and the pressure magnitude sensed by the strain bridge measurement unit 6.

[0041] As a feasible embodiment of the present invention, the present invention can calibrate a pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure using a pressure calibration device. The data measured by the pressure sensing device is corrected by the position and magnitude of the pressure applied by the calibration device, so that the pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure can accurately measure the magnitude and position of pressure.

[0042] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure, characterized in that, It includes an elastic layer, a piezoresistive sensing unit, and a substrate arranged vertically in sequence; The piezoresistive sensing unit is a plurality of units, and the plurality of piezoresistive sensing units are distributed on the surface of the substrate; The piezoresistive sensing unit has a force plate on the side away from the substrate. At least two pins extend from the force plate toward the substrate. The ends of the two pins away from the force plate abut against a strain bridge measuring unit. The two pins abut against the pressure loading surface of the strain bridge measuring unit.

2. The pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure according to claim 1, characterized in that, The force-bearing plate has four pins extending from one side toward the base plate. The end of each pin away from the force-bearing plate abuts against two sets of strain gauge measurement units. The four pins abut against the pressure loading surfaces of the two sets of strain gauge measurement units respectively.

3. The pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure according to claim 2, characterized in that, The end of the ejector pin facing the strain gauge measurement unit is also provided with a deformation beam. The deformation beam is made of elastic material and has an "I" shaped structure. Two sets of strain gauge measurement units are respectively attached to the side of the deformation beam away from the ejector pin, and both strain gauge measurement units have a strip-shaped structure. The two strain gauge measurement units are respectively attached to the beam structure surface of the deformation beam.

4. The pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure according to claim 2, characterized in that, The two strain bridge measurement units are connected by a conductive thin film, which is electrically connected to the substrate.

5. The pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure according to claim 3, characterized in that, A first through hole is correspondingly formed on the substrate, the force plate is attached to the surface of the substrate, and the ejector pin passes through the first through hole and abuts against the strain bridge measurement unit.

6. The pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure according to claim 5, characterized in that, The deformable beam is also connected to a fixing plate on the side facing the substrate, and the fixing plate is fixedly connected to the substrate; a second through hole is provided on the fixing plate, and the ejector pin passes through the second through hole and abuts against the deformable beam.

7. The pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure according to claim 3, characterized in that, The deformable beam has multiple crimping grooves on the side facing the ejector pin, and the end of the ejector pin facing the deformable beam abuts against the crimping groove.

8. The pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure according to claim 1, characterized in that, Multiple piezoresistive sensing units are arranged in an array on the surface of the substrate.

9. The pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure according to claim 1, characterized in that, It also includes a mounting housing with an opening at one end. The opening is provided with the elastic layer, and the elastic layer and the mounting housing form a closed space. The piezoresistive sensing unit, the substrate, the force plate, and the strain bridge measurement unit are all disposed within the closed space formed by the elastic layer and the mounting housing.

10. A pressure detection method based on the fusion of strain gauge bridge and piezoresistive pressure, wherein the detection is performed using a pressure sensing device based on the fusion of strain gauge bridge and piezoresistive pressure as described in any one of claims 1 to 9, characterized in that, Includes the following steps: S1. The piezoresistive sensing unit senses pressure, and the pressure sensing position is determined based on the position of the piezoresistive sensing unit on the substrate surface. S2, the strain gauge bridge measurement unit senses the pressure magnitude; S3. The pressure location and magnitude are obtained by fusing the pressure sensing position obtained by the piezoresistive sensing unit and the pressure magnitude sensed by the strain gauge bridge measurement unit.

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