Curved surface pressure sensor based on magnetic field

Abstract

The utility model discloses a curved surface pressure sensor based on a magnetic field, and aims to solve the problem that when an existing flexible pressure sensor based on the magnetic field is matched with a complex curved surface, wiring of a PCB is complex, or the consistency of readings of different Hall elements is low, and consequently the accuracy of a measurement result is reduced. The device comprises a flexible magnet layer, a hard shell layer and a flexible printed circuit board, the hard shell layer is a curved surface, and the inner wall of the hard shell layer is uniformly provided with mounting grooves for placing the stiffening plates; the flexible printed circuit board is provided with a plurality of reinforcing plates which are arranged at intervals, and the plurality of Hall elements are arranged on the plurality of reinforcing plates in a one-to-one correspondence manner; the flexible printed circuit board is connected with the hard printed circuit board through a connector; the problem of adaptation to a complex curved surface is solved, the consistency of the interlayer spacing of the Hall sensor and the flexible magnet is kept, the measurement result of the sensor is more accurate and stable, and the sensor has the capacity of covering the shape of a complex product in a large range.

Description

Technical Field

[0001] This application relates to the field of pressure sensor technology, and specifically to a curved surface pressure sensor based on a magnetic field. Background Technology

[0002] Magnetic field pressure sensors typically consist of a flexible magnetic membrane (possibly with an additional elastic layer) that generates a magnetic field, an intermediate rigid substrate, and a sensor and its integrated circuit for detecting the magnetic field. When pressure is applied to a deformable material, the deformation of the material causes a change in the magnetic field, which is captured by the magnetic sensor, thus reflecting the pressure. These sensors are commonly used on planar or developable surfaces (such as cylinders, cones, etc.). Developable surfaces can be bent without stretching, shrinking, wrinkling, or tearing, thus approximating a planar surface.

[0003] However, challenges remain regarding the "sensor layout and integrated circuit design" for magnetic field-based flexible pressure sensors. Ordinary printed circuit boards (PCBs) are typically planar and cannot be fitted to complex curved surfaces. One possible solution is to break down the complex curved surface into multiple smaller, approximately planar surfaces, each fitted with a separate PCB. However, this approach has several drawbacks: if the segmented surfaces are too small, the production and wiring of different PCBs become extremely complex; conversely, if the segmented surfaces are too large, the PCBs may not fit perfectly, leading to uneven distances between the Hall sensors and the surface. This not only reduces the consistency of readings from different Hall elements, affecting the accuracy and reliability of the measurement results, but may also result in some Hall sensors being too far from the surface to effectively measure the magnetic field. Utility Model Content

[0004] To address this issue, this application provides a magnetic field-based curved surface pressure sensor to solve the problem that existing magnetic field-based flexible pressure sensors suffer from complex PCB board traces or low consistency between readings of different Hall elements when adapting to complex curved surfaces, leading to reduced accuracy of measurement results.

[0005] To achieve the above objectives, this application provides the following technical solution:

[0006] In a first aspect, a curved pressure sensor based on a magnetic field includes: a flexible magnet layer located on the outer layer that is capable of generating a magnetic field, a rigid shell layer located in the middle layer, a flexible printed circuit board located in the inner layer, and a Hall sensor array.

[0007] The rigid shell layer is curved, and multiple mounting grooves are evenly provided on the inner wall of the rigid shell layer. The bottom surface of the mounting groove is a plane, which is parallel to the tangent plane of the nearby curved surface, and the distance between the plane and the outer surface of the rigid shell layer is set to a fixed value.

[0008] The flexible printed circuit board is provided with a plurality of reinforcing plates arranged at intervals, and the plurality of reinforcing plates are placed one-to-one in the plurality of mounting slots; the Hall sensor array is composed of a plurality of Hall elements, and the plurality of Hall elements are disposed one-to-one on the plurality of reinforcing plates, such that each Hall element is equidistant from the outer surface of the rigid shell layer and parallel to the tangent plane of its nearby outer surface; the flexible printed circuit board is also connected to the rigid printed circuit board.

[0009] Optionally, the reinforcing plate is fixed to the inner wall of the mounting groove by adhesive or snap-fit ​​device.

[0010] Optionally, the Hall element is mounted on a flexible printed circuit board by soldering.

[0011] Optionally, the rigid printed circuit board is disposed inside the rigid housing layer, and the rigid printed circuit board is also connected to the host computer.

[0012] Optionally, the flexible printed circuit board is connected to the rigid printed circuit board via a connector.

[0013] Optionally, the rigid printed circuit board integrates a microcontroller unit, a data transmission interface, and the connector.

[0014] Optionally, the rigid shell layer is further provided with reinforcing ribs on the side away from the flexible magnet layer.

[0015] Secondly, a method for fabricating a curved surface pressure sensor based on a magnetic field includes the following steps:

[0016] S1. Select the target product shell with curved surfaces;

[0017] S2. Design and fabrication of the flexible magnet layer;

[0018] S3, Magnetization of the flexible magnet layer;

[0019] S4, Design of Hall sensor array;

[0020] S41. First, extract the thin-walled portion of the target product's outer shell, analyze the curved surface of the thin wall, and make preliminary point selections.

[0021] S42. Place a Hall element at each selected point;

[0022] S43. Design a reinforcing plate that matches the Hall element directly below it, and center the Hall element.

[0023] S5. Adaptive design and manufacturing of the target product's casing;

[0024] S51. Based on the reinforcing plate designed in S4, a mounting groove is opened on the inner wall of the target product shell, so that the reinforcing plate can be precisely embedded in the mounting groove.

[0025] S52. The outer shell of the target product is manufactured using 3D printing.

[0026] S6, design and fabrication of flexible printed circuit boards and rigid printed circuit boards;

[0027] S61. Based on the adjusted position of the reinforcing plate, design a flexible printed circuit board, and make the reinforcing plate on the flexible printed circuit board fully embedded in the mounting slot opened in the housing. One end of the flexible printed circuit board is inserted into the connector on the rigid printed circuit board.

[0028] S62. A rigid printed circuit board is installed at a suitable location inside the casing of the target product;

[0029] After printing S63, flexible printed circuit boards and rigid printed circuit boards, surface mount electronic components are attached, connected to the host computer, and tested without error.

[0030] S7. Wrap the flexible magnet layer around the outer wall of the target product casing.

[0031] Thirdly, a calibration method for a curved surface pressure sensor based on a magnetic field includes the following steps:

[0032] S1. Apply pressure to the flexible magnet layer, and record and view the output signal of each Hall element under different pressures through the host computer;

[0033] S2. Based on the recorded data, establish a mathematical model to describe the relationship between the output of the Hall element and the applied pressure, and determine the pressure parameters of each Hall element.

[0034] Compared with the prior art, this application has at least the following beneficial effects:

[0035] 1. Based on further analysis and research of existing technical problems, this application provides a magnetic field-based curved surface pressure sensor, successfully solving the adaptation problem to complex curved surfaces while maintaining consistency in the distance between the Hall sensor and the flexible magnet layer. This simplifies the correspondence between magnetic field changes and deformation, making the sensor's measurement results more accurate and stable. It has the ability to cover a wide range of complex product shapes and is applicable to various objects with complex curved surfaces, such as robot shells, home appliances, factory equipment, and toy shells. By using a flexible circuit board, the Hall sensor can be tightly attached to the curved surface, maintaining consistent distance with the flexible magnet layer. This effectively avoids measurement errors caused by inconsistent spacing between different sensors and the magnetic film, and also avoids the complex wiring and routing problems associated with using a large number of rigid printed circuit boards for segmenting curved surfaces.

[0036] In addition, the reinforcing plate helps to enhance the overall structural strength and stability of the flexible printed circuit board, especially at the location where the Hall sensor is soldered. The reinforcing plate can ensure the reliability and measurement accuracy of the Hall sensor during use, prevent the flexible printed circuit board from shifting due to external forces or its own deformation, and further improve the stability of the Hall sensor and the accuracy of the measurement data.

[0037] 2. This application also provides a calibration method for a curved surface pressure sensor based on a magnetic field. Through calibration, it can be used for subsequent pressure measurement and calibration, and also improves the measurement accuracy.

[0038] 3. The reinforcing plate of this application is fixed to the inner wall of the mounting groove by adhesive or snap-on device, which has the advantage of convenient installation.

[0039] 4. The rigid shell layer of this application has a reinforcing rib on the side away from the flexible magnet layer, which enhances the overall mechanical strength and stability of the rigid shell layer. Attached Figure Description

[0040] To more intuitively illustrate the prior art and this application, exemplary drawings are provided below. It should be understood that the specific shapes and structures shown in the drawings should not generally be regarded as limiting conditions for implementing this application; for example, based on the technical concept disclosed in this application and the exemplary drawings, those skilled in the art are able to easily make conventional adjustments or further optimizations to the addition / reduction / classification, specific shapes, positional relationships, connection methods, size ratios, etc. of certain units (components).

[0041] Figure 1 A schematic diagram of the rigid housing layer and the flexible printed circuit board with reinforcing plate in a pressure sensor provided in one embodiment of this application;

[0042] Figure 2 for Figure 1 The diagram shown illustrates the rigid shell layer in a transparent state.

[0043] Figure 3 for Figure 1 A partial schematic diagram;

[0044] Figure 4 for Figure 3 The front view shown;

[0045] Figure 5 for Figure 1 A schematic diagram of the structure with a flexible magnet layer in the middle;

[0046] Figure 6 for Figure 5 The diagram shown illustrates the flexible magnet layer in a transparent state.

[0047] Figure 7 for Figure 5 A partial schematic diagram;

[0048] Figure 8 for Figure 7 The front view shown;

[0049] Figure 9 for Figure 5 A planar unfolded view of a flexible printed circuit board;

[0050] Figure 10 for Figure 5 A cross-sectional view of the Hall sensor located on the side away from the flexible magnet layer;

[0051] Figure 11 for Figure 10 A schematic diagram of the state when pressure is applied;

[0052] Figure 12 for Figure 5 A cross-sectional view of the Hall sensor located on the side closest to the flexible magnet layer;

[0053] Figure 13 This is a circuit block diagram of a pressure sensor provided in one embodiment of this application.

[0054] Explanation of reference numerals in the attached figures:

[0055] 1. Flexible magnet layer; 2. Rigid shell layer; 21. Reinforcing ribs;

[0056] 3. Flexible printed circuit board; 4. Hall sensor; 5. Reinforcing plate;

[0057] 6. Rigid printed circuit board; 7. Host computer. Detailed Implementation

[0058] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0059] In the description of this application: unless otherwise stated, "a plurality of" means two or more. The terms "first," "second," "third," etc., in this application are intended to distinguish the objects referred to and do not have any special meaning in terms of technical connotation (e.g., they should not be construed as an emphasis on importance or order). Expressions such as "comprising," "including," and "having" also mean "not limited to" (certain units, components, materials, steps, etc.).

[0060] The terms used in this application, such as "upper," "lower," "left," "right," and "middle," are generally used to indicate the general relative positional relationship for the purpose of intuitive understanding by referring to the accompanying drawings, and are not absolute limitations on the positional relationship in the actual product.

[0061] One embodiment of this application provides a curved surface pressure sensor based on a magnetic field, such as... Figures 1-13 As shown, it includes: a flexible magnet layer 1 located on the outer layer, a rigid shell layer 2 located in the middle layer, a flexible printed circuit board 3 located in the inner layer, and a Hall sensor array; the flexible magnet layer 1 is wrapped around the outer wall of the rigid shell layer 2.

[0062] The rigid shell layer 2 has a complex curved surface shape, and multiple mounting slots are evenly provided on the inner wall of the rigid shell layer 2. The mounting slots are used to place the reinforcing plate 5 of the flexible printed circuit board 3. The bottom surface of each mounting slot is a small plane, which is parallel to the tangent plane of its nearby curved surface, and the distance from the outer surface of the rigid shell layer 2 is set to a fixed value.

[0063] The flexible printed circuit board 3 is provided with multiple reinforcing plates 5 arranged at intervals, and the multiple reinforcing plates 5 are placed one-to-one in multiple mounting slots; the Hall sensor array is composed of multiple Hall sensors 4 (Hall elements), and the multiple Hall elements are arranged one-to-one on the multiple reinforcing plates 5, so that each Hall element is equidistant from the outer surface of the rigid shell layer 2 and parallel to the tangent plane of its nearby outer surface, thereby ensuring that the response of each Hall element to the magnetic field change of the outer flexible magnet layer 1 is consistent; the flexible printed circuit board 3 is connected to the rigid printed circuit board 6 through a connector, and the rigid printed circuit board 6 is used to collect and summarize the data of the Hall sensors; the rigid printed circuit board 6 can be disposed inside the rigid shell layer 2, and the rigid printed circuit board 6 is also connected to the host computer 7.

[0064] The reinforcing plate 5 is used to enhance the overall structural strength and stability of the flexible printed circuit board 3, especially at the location where the Hall sensor 4 is soldered. It can ensure the reliability and measurement accuracy of the Hall sensor 4 and ensure that the flexible printed circuit board 3 will not deform or shift during use.

[0065] The flexible magnet layer 1 (flexible magnetic film) can generate a magnetic field. When pressure is applied to the flexible magnetic film, the flexible magnetic film will deform, causing the distribution of the magnetic field to change. The Hall sensor 4 is used to detect the change in the magnetic field. When the deformation of the flexible magnet layer 1 causes the magnetic field to change, the Hall sensor 4 can capture these changes and convert them into electrical signals. These electrical signals are then processed by the rigid printed circuit board 6, which converts them into pressure values ​​and performs further signal processing and transmission.

[0066] The flexible printed circuit board 3 and the rigid printed circuit board 6 can also be connected by direct soldering or adhesive bonding.

[0067] There are two ways to install the Hall sensor 4 on the reinforcing plate 5, as detailed below:

[0068] The first method: The Hall sensor 4 is mounted on the reinforcing plate 5 and located on the side away from the flexible magnet layer 1, such as... Figure 10 , Figure 11 As shown;

[0069] The second method: The Hall sensor 4 is mounted on the reinforcing plate 5 and located on the side close to the flexible magnet layer 1, such as... Figure 12 As shown.

[0070] Preferably, the reinforcing plate 5 is fixed to the inner wall of the mounting groove by adhesive or snap-fit ​​device, so that the reinforcing plate 5 can be easily fixed inside the rigid shell layer 2.

[0071] The dimensions of the reinforcing plate 5 are determined according to actual needs. When slotting the rigid shell layer 2, if the rigid shell layer 2 itself is too thin to allow for a sufficiently deep mounting slot, the thickness can be increased around the mounting slot to ensure that the reinforcing plate 5 can be securely embedded inside the shell. This provides more stable support and more reliable fixation for the reinforcing plate 5 without changing the overall thickness of the shell.

[0072] Preferably, the Hall element is mounted on the flexible printed circuit board 3 by soldering.

[0073] More preferably, the rigid printed circuit board 6 integrates a microcontroller unit (MCU), a data transmission interface (CAN), and connectors. Multiple Hall sensors 4 are connected to the microcontroller unit via an IIC bus, and the Hall addresses on the same IIC bus are different. The rigid printed circuit board 6 is connected to the host computer 7 via the data transmission interface, and the connectors are used to connect to the flexible printed circuit board 3.

[0074] Preferably, the side of the rigid shell layer 2 away from the flexible magnet layer 1 is also provided with a reinforcing rib 21, which can enhance the overall mechanical strength and stability of the rigid shell layer 2; in addition, screw holes can also be provided on the rigid shell layer 2 to fix the shell.

[0075] The working process of the above embodiments:

[0076] 1. Initial state: When no external force is applied, the flexible magnet layer 1 remains flat and the magnetic field is uniformly distributed;

[0077] 2. Under pressure: When pressure is applied to the flexible magnet layer 1, the flexible magnet layer 1 deforms, and the magnetic field distribution changes accordingly.

[0078] 3. Magnetic field detection: The Hall sensor 4 on the flexible printed circuit board 3 detects the change in magnetic field and converts it into an electrical signal;

[0079] 4. Signal processing: The rigid printed circuit board 6 processes the electrical signals to calculate the magnitude and distribution of the pressure.

[0080] Based on the above-mentioned magnetic field-based curved surface pressure sensor, this application also provides a method for manufacturing a magnetic field-based curved surface pressure sensor, including the following steps:

[0081] S1. Select the target product shell (rigid shell layer 2) with a complex curved surface;

[0082] S2, Design and fabrication of flexible magnet layer 1; its fabrication process involves uniformly mixing magnetic powder into resin, then shaping it into the required shape through injection molding, compression molding and other molding processes, and finally magnetizing it; the magnetic field generated by the magnetic film has a certain distribution and is consistent along the curved surface; specifically, taking thickness magnetization as an example, the magnetic field direction is almost perpendicular to the magnetic film.

[0083] S3, Magnetization of flexible magnet layer 1;

[0084] The flexible magnet layer 1 is magnetized using a pulse magnetization device, so that the magnetic field generated by the flexible magnet layer 1 is relatively uniformly distributed along the flexible magnet layer 1.

[0085] S4, Design of Hall sensor array;

[0086] S41. First, extract the thin-walled portion of the target product's outer shell, analyze the curved surface of the thin wall, and make preliminary point selections. The selected points should be distributed as evenly as possible, with consistent spacing, covering the entire curved surface of the outer shell.

[0087] S42. Place a Hall element at each selected point;

[0088] S43. Design a reinforcement piece that matches the Hall element directly below it, and center the Hall element.

[0089] S5. Adaptive design and manufacturing of the target shell;

[0090] S51. According to the reinforcing plate 5 designed in S4, an installation groove is opened on the inner wall of the target product shell, so that the reinforcing plate 5 can be precisely embedded in the installation groove.

[0091] S52. Adjust the position of the reinforcing rib 21 inside the outer shell and the screw hole, and adjust the position of the groove appropriately so that the two do not conflict.

[0092] S53. The outer shell of the target product is manufactured using 3D printing.

[0093] Design and fabrication of S6, flexible printed circuit board 3 and rigid printed circuit board 6;

[0094] S61. Based on the adjusted position of the reinforcing plate 5 and the positions of the reinforcing ribs 21 and screw holes, design the flexible printed circuit board 3, so that the reinforcing plate 5 on the flexible printed circuit board 3 can be fully embedded in the mounting groove opened in the shell, and one end of the flexible printed circuit board 3 is inserted into the connector on the rigid printed circuit board 6.

[0095] S62. A rigid printed circuit board 6 is installed at a suitable location inside the casing of the target product.

[0096] After printing S63, flexible printed circuit board 3 and rigid printed circuit board 6, surface mount electronic components, burn embedded software program, connect to host computer 7 and test to ensure no errors.

[0097] S7. Wrap the flexible magnet layer 1 around the outer wall of the target product casing.

[0098] Preferably, S2 above can be divided into the following steps:

[0099] S21. Based on the shape of the target product's outer shell, design a flexible magnet layer 1 of a certain thickness, and design a mold for the flexible magnet layer 1, which is then manufactured using CNC machining.

[0100] S22. Mix the magnetic powder and silicone (with crosslinking agent / catalyst) in a 1:1 ratio and stir evenly. Be careful to avoid generating air bubbles. If air bubbles are generated, they need to be removed.

[0101] S23. Inject the well-stirred suspension into the mold under pressure and wait for it to solidify and take shape;

[0102] S24. Test, modify and repeat the above steps until the flexible magnet layer 1 can wrap and fit the target shell.

[0103] The magnetic field-based curved surface pressure sensor provided in this application has the ability to cover a large area of ​​complex product shapes, especially in applications requiring the measurement of pressure distribution on complex curved surfaces, such as robot shells, household appliances, factory equipment, and toy shells. The following is a specific manufacturing method using an electronic skin adapted to a robot shell as an example, including the following steps:

[0104] S1. Select the target product shell (rigid shell layer 2) with a complex curved surface; select a robot structural shell, in this case, the robot's elbow joint;

[0105] S2, Design and fabrication of flexible magnet layer 1:

[0106] S21. Based on the robot's shell shape, design flexible magnet layer 1 (flexible magnetic film), with a magnetic film thickness of approximately 3mm, and design a mold for the flexible magnetic film, which is then manufactured using CNC machining.

[0107] S22. Mix the magnetic powder and silicone (with crosslinking agent / catalyst) in a 1:1 ratio and stir evenly. Be careful to avoid generating air bubbles. If air bubbles are generated, they need to be removed.

[0108] S23. Inject the well-stirred suspension into the mold under pressure and wait for it to solidify and take shape;

[0109] S24. Test, modify and repeat the above steps until the flexible magnetic film can wrap and fit the robot shell.

[0110] S3, Magnetization of flexible magnet layer 1:

[0111] A pulse magnetization device is used to magnetize the magnetic film, so that the magnetic field generated by the magnetic film is relatively uniformly distributed along the magnetic film.

[0112] S4, Hall array design:

[0113] S41. First, extract the thin-walled part of the robot shell, analyze the thin-walled surface in a way similar to a UV curve, and make preliminary point selections. The selected points should be distributed as evenly as possible and the spacing should be consistent (e.g., 10mm) to cover the entire shell surface.

[0114] S42. Place a Hall element (e.g., package size 3×3mm) at each selected point, and make the x-axis of the Hall element the same as the u or v direction in the uv curve in the previous step S41.

[0115] S43. Design a reinforcing plate 5 (e.g., a 5×5mm rectangle with a thickness of 1mm) that is appropriately sized to fit the Hall element directly below it, and center the Hall element.

[0116] S5. Adaptive design and manufacturing of the robot shell:

[0117] S51. Based on the reinforcing plate 5 designed in the previous step, an installation groove is opened on the inner wall of the robot shell, so that the reinforcing plate 5 can be precisely embedded in the installation groove.

[0118] S52. Adjust the position of the reinforcing rib 21 inside the robot shell and the screw hole, and adjust the position of the mounting slot appropriately to ensure that the two do not conflict.

[0119] S53, The robot's outer shell is manufactured using 3D printing;

[0120] Design and fabrication of S6, flexible printed circuit board 3 (FPC) and rigid printed circuit board 6 (PCB);

[0121] S61. Based on the adjusted position of the reinforcing plate 5 and the positions of the reinforcing rib 21 and screw holes, design the flexible printed circuit board 3 (FPC) so that the FPC strip will not interfere with the reinforcing rib 21 and screw holes, and the reinforcing plate 5 on the FPC can be fully embedded in the mounting slot opened in the housing. One end of the FPC is inserted into the connector on the rigid printed circuit board 6.

[0122] S62. A rigid printed circuit board 6 (PCB) is designed in a suitable position inside the robot shell. The rigid printed circuit board 6 integrates a microcontroller unit (MCU), a data transmission interface (CAN), and a connector for connecting to the flexible printed circuit board 3.

[0123] After printing S63, flexible printed circuit board 3 and rigid printed circuit board 6, surface mount electronic components, burn embedded software program, connect to host computer 7 and test to ensure no errors.

[0124] S7. Wrap the flexible magnet layer 1 around the outer wall of the rigid shell layer 2.

[0125] In addition, this application also provides a calibration method for a curved surface pressure sensor based on a magnetic field, comprising the following steps:

[0126] S1. Apply pressure to the flexible magnet layer, and record and view the output signal of each Hall element under different pressures through the host computer;

[0127] S2. Based on the recorded data, establish a mathematical model to describe the relationship between the output of the Hall element and the applied pressure, and determine the pressure parameters of each Hall element for subsequent pressure measurement and calibration.

[0128] In summary, this application has at least the following advantages:

[0129] 1. The pressure sensor provided in this application has the ability to cover a wide range of complex product shapes and can be applied to various objects with complex curved surfaces, such as robot shells, home appliances, factory equipment, and toy shells. By using a flexible circuit board, the Hall sensor can be closely attached to the curved surface, maintaining a consistent distance with the flexible magnet layer. This effectively avoids measurement errors caused by inconsistent spacing between different sensors and the magnetic film, and also avoids the complex wiring problems caused by using a large number of rigid printed circuit boards due to the segmentation of curved surfaces.

[0130] 2. The reinforcing plate is used to enhance the overall structural strength and stability of the flexible printed circuit board, especially at the location where the Hall sensor is soldered. The reinforcing plate can ensure the reliability and measurement accuracy of the Hall sensor during use, prevent the flexible printed circuit board from shifting due to external force or its own deformation, and further improve the stability of the Hall sensor and the accuracy of the measurement data.

[0131] In summary, the pressure sensor of this application successfully solves the problem of adapting to complex curved surfaces, avoids the problems of complex wiring and routing, and maintains the consistency of the spacing between the Hall sensor and the flexible magnet layer (flexible magnetic film), which helps to simplify the correspondence between magnetic field changes and deformation, making the sensor's measurement results more accurate and stable.

[0132] The technical features of the above embodiments can be combined in any way (as long as there is no contradiction in the combination of these technical features). For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; these embodiments not explicitly written should also be considered to be within the scope of this specification.

Claims

1. A curved surface pressure sensor based on a magnetic field, characterized in that, include: The outer layer consists of a flexible magnet layer that generates a magnetic field, the middle layer consists of a rigid shell layer, the inner layer consists of a flexible printed circuit board, and the inner layer consists of a Hall sensor array. The rigid shell layer is curved, and multiple mounting grooves are evenly provided on the inner wall of the rigid shell layer. The bottom surface of the mounting groove is a plane, which is parallel to the tangent plane of the nearby curved surface, and the distance between the plane and the outer surface of the rigid shell layer is set to a fixed value. The flexible printed circuit board is provided with a plurality of reinforcing plates arranged at intervals, and the plurality of reinforcing plates are placed one-to-one in the plurality of mounting slots; The Hall sensor array consists of multiple Hall elements, which are arranged one-to-one on the multiple reinforcing plates, such that each Hall element is equidistant from the outer surface of the rigid shell layer and parallel to the tangent plane of its nearby outer surface; the flexible printed circuit board is also connected to the rigid printed circuit board.

2. The curved surface pressure sensor based on a magnetic field according to claim 1, characterized in that, The reinforcing plate is fixed to the inner wall of the mounting groove by adhesive or snap-on device.

3. The curved surface pressure sensor based on a magnetic field according to claim 1, characterized in that, The Hall element is mounted on a flexible printed circuit board by soldering.

4. The curved surface pressure sensor based on a magnetic field according to claim 1, characterized in that, The rigid printed circuit board is disposed inside the rigid housing layer, and the rigid printed circuit board is also connected to the host computer.

5. The curved surface pressure sensor based on a magnetic field according to claim 4, characterized in that, The flexible printed circuit board is connected to the rigid printed circuit board via a connector.

6. The curved surface pressure sensor based on a magnetic field according to claim 5, characterized in that, The rigid printed circuit board integrates a microcontroller unit, a data transmission interface, and the connector.

7. The curved surface pressure sensor based on a magnetic field according to claim 1, characterized in that, The rigid shell layer is further provided with reinforcing ribs on the side away from the flexible magnet layer.

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