Three-dimensional array type magnetic tactile sensor

Abstract

The utility model relates to the technical field of tactile sensing, in particular to a three-dimensional array type magnetic tactile sensor. The three-dimensional array type magnetic tactile sensor comprises a flexible circuit board layer, an elastic layer and a flexible magnet layer which are sequentially stacked and bonded from bottom to top, when the flexible magnet layer deforms due to external pressure, the surrounding magnetic field intensity is changed, and the flexible circuit board layer measures external force by sensing the magnetic field change of the flexible magnet layer. The elastic layer is used for expanding the external force measurement range of the flexible circuit board layer. The flexible magnet layer comprises a top-layer flexible body and a plurality of flexible magnets embedded in the top-layer flexible body, and the flexible magnets are used as contacts. The device simulates hand touch perception, has a wide force measurement range, can accurately detect tiny force change, and improves sensitivity.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of tactile sensing, particularly to a three-dimensional array type magnetic tactile sensor. BACKGROUND

[0002] Tactile sensing plays a core role in robotics, enabling robots to perceive and respond to the external environment in a manner similar to humans. High-performance tactile sensors enhance the ability of robots in fine manipulation, object recognition, and human-robot interaction, and are crucial for achieving intelligent and flexible robotic systems. In daily life, human hands can grasp and manipulate objects of various shapes and sizes because the rich tactile receptors in the skin of the fingers can perceive three-dimensional forces of contact and adjust the grasping force of the fingers in real time to ensure safe grasping and manipulation. Therefore, it is particularly urgent to develop high-performance three-dimensional force sensor technology to meet the demand for tactile feedback.

[0003] In recent years, research on three-dimensional force sensors has made some progress, and tactile sensors based on various mechanisms such as resistance, capacitance, piezoelectricity, and optics have been developed. Compared with three-dimensional force tactile sensors based on other mechanisms, magnetic sensors have the advantages of high sensitivity, high resolution, non-contact measurement, strong stability, and resistance to environmental interference, making them an important direction in the field of tactile sensing. The principle of magnetic tactile sensors is to use a mixture of magnetic and flexible materials as a magnetic field source. When an external force acts on the magnetic material, it will cause deformation or displacement. By detecting the change in the magnetic field with a magnetic sensor, the size and direction of the external force can be obtained, thereby realizing tactile sensing. Based on this principle, contact sensors of different shapes, sizes, and sensitivities can be designed, and integrating such sensors can enhance the ability of robots to grasp fragile objects, deformable objects, and identify object properties.

[0004] In previous studies, the structure design of magnetic composites has been diverse, but most tactile sensors based on magnetic field detection principles have problems such as small measurement range at high sensitivity or poor sensitivity at large measurement range. UTILITY MODEL CONTENT

[0005] To solve the problem of existing tactile sensors having a small measurement range at high sensitivity or poor sensitivity at a large measurement range, the utility model provides a three-dimensional array type magnetic tactile sensor.

[0006] To achieve the above-mentioned purpose, the utility model adopts the following technical solutions:

[0007] The utility model provides a three -dimensional array formula magnetic touch sensor, including the flexible circuit board layer, elastic layer and flexible magnet layer of the adhesion from below to above in turn, wherein the flexible magnet layer changes the magnetic field intensity around when the deformation is generated, the flexible circuit board layer measures the external force through the magnetic field change of flexible magnet layer sensing, and the elastic layer is used for expanding the external force measurement range of flexible circuit board layer.

[0008] The flexible magnet layer includes a top layer flexible body and a plurality of flexible magnets embedded in the top layer flexible body. The flexible magnets serve as touch points and can deform under external pressure, thereby changing the surrounding magnetic field intensity.

[0009] The front surface of the flexible magnet is a square structure protruding from the top surface of the top layer flexible body, and the bottom surface of the flexible magnet is a cross hollow structure recessed from the bottom surface of the top layer flexible body.

[0010] The elastic layer includes a middle layer flexible body and a plurality of springs embedded in the middle layer flexible body.

[0011] The flexible circuit board layer includes a bottom layer flexible body and a flexible hard brush circuit board embedded above the bottom layer flexible body. The flexible hard brush circuit board is provided with a plurality of chips corresponding to the flexible magnets.

[0012] The chips are Hall sensors, and the plurality of Hall sensors are arranged in a square array.

[0013] The three-dimensional array magnetic touch sensor provided by the utility model simulates human hand tactile perception, has a wide force measurement range, can accurately detect small force changes, and improves sensitivity. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is a structural schematic view of the three-dimensional array magnetic touch sensor of the utility model.

[0015] Figure 2 It is a structural schematic view of the flexible magnet layer in the utility model.

[0016] Figure 3 It is a structural schematic view of the flexible hard brush circuit board in the utility model.

[0017] Figure 4 It is a structural schematic view of the magnet layer mold in the utility model: (a) is a structural schematic view of the upper mold of the magnet layer, and (b) is a structural schematic view of the lower mold of the magnet layer.

[0018] Figure 5 It is a structural schematic view of the elastic layer mold in the utility model: (a) is a structural schematic view of the upper mold of the elastic layer, and (b) is a structural schematic view of the lower mold of the elastic layer.

[0019] In the figure: 1 - lower mold of magnet layer, 2 - square groove, 3 - upper mold of magnet layer, 4 - cross convex, 5 - lower mold of elastic layer, 6 - lower spring fixing column, 7 - upper mold of elastic layer, 8 - upper spring fixing column, 10 - cross hollow structure, 11 - flexible magnet, 12 - top layer flexible body, 13 - spring, 14 - middle layer flexible body, 15 - chip, 16 - flexible hard brush circuit board, 17 - bottom layer flexible body. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical scheme and advantages of the utility model more clear, the utility model is described below in combination with the drawings and specific embodiments.

[0021] Referring to Figures 1 to 3 The utility model provides a three -dimensional array formula magnetic touch sensor, including by lower to upper sequentially laminated and bonded flexible circuit board layer, elastic layer and flexible magnet layer, wherein flexible magnet layer is changed surrounding magnetic field intensity when deformation occurs under external pressure, flexible circuit board layer measures external force through sensing the magnetic field change of flexible magnet layer, and elastic layer is used for expanding the external force measurement range of flexible circuit board layer.

[0022] Referring to Figure 1 And Figure 2 In the embodiment of the utility model, the flexible magnet layer includes the top layer flexible body 12 and the plurality of flexible magnets 11 embedded on the top layer flexible body 12, and the flexible magnet 11 is used as a contact point and can be deformed under external pressure, and then the surrounding magnetic field intensity is changed.

[0023] Specifically, the front surface of the flexible magnet 11 is a square structure protruding on the upper surface of the top layer flexible body 12, which can detect normal force and radial force simultaneously, and the bottom surface of the flexible magnet 11 is a cross hollow structure 10 recessed in the lower surface of the top layer flexible body 12 to improve the sensitivity of the sensor.

[0024] Referring to Figure 1 In the embodiment of the utility model, the elastic layer includes the middle layer flexible body 14 and the plurality of springs 13 embedded in the middle layer flexible body 14.

[0025] Referring to Figure 1 , Figure 3 In the embodiment of the utility model, the flexible circuit board layer includes the bottom layer flexible body 17 and the flexible hard brush circuit board 16 embedded above the bottom layer flexible body 17, and the flexible hard brush circuit board 16 is provided with a plurality of chips 15 corresponding to the flexible magnets 11.

[0026] In this embodiment, the chip 15 is a Hall sensor, and the plurality of Hall sensors are arranged in a 3x3 array. Correspondingly, the flexible magnets 11 on the top layer of flexible body 12 are arranged in a 3x3 array. Specifically, the top layer of flexible body 12, the middle layer of flexible body 14 and the bottom layer of flexible body 17 are all organic elastomers made of silicone material, specifically Excof l e 00-30 silicone.

[0027] The three-dimensional array type magnetic haptic sensor provided by the utility model is designed as a sandwich structure form, the flexible magnet layer of the top layer changes the magnetic field intensity around when being deformed by external pressure, the changes are detected by the Hall sensor embedded in the bottom layer, then the changes are converted into electric signals through the flexible printed circuit board (FPCB), so that the haptic perception is obtained. The middle layer is combined by the soft organic elastomer (Excof l e 00-30) and spring, the external force measurement range of the sensor is expanded, so the utility model has the advantages of high sensitivity, wide range and the like.

[0028] The manufacturing method of the three-dimensional array type magnetic haptic sensor provided by the utility model comprises the following steps:

[0029] The flexible magnet layer is manufactured through a magnet layer mold;

[0030] The elastic layer is manufactured through an elastic layer mold;

[0031] The flexible circuit board layer is manufactured;

[0032] After the flexible circuit board layer, the elastic layer and the flexible magnet layer are sequentially bonded through the Excof l e 00-30 silicone solution, they are put into a drying box again and solidified for 2 hours. Finally, the flexible circuit board layer, the elastic layer and the flexible magnet layer are firmly combined together to form a complete sensor structure.

[0033] Referring to Figure 4 As shown in (a)-(b), in the embodiment of the utility model, the magnet layer mold comprises a magnet layer lower mold 1 and a magnet layer upper mold 3, wherein the inner surface of the magnet layer lower mold 1 is arrayed with 3x3 square grooves 2, and the inner surface of the magnet layer upper mold 3 is arrayed with cross-shaped protrusions 4 corresponding to the square grooves 2 on the magnet layer lower mold 1; when the magnet layer upper mold 3 and the magnet layer lower mold 1 are closed, the cross-shaped protrusions 4 are accommodated in the corresponding square grooves 2, and a forming gap is left between the cross-shaped protrusions 4 and the square grooves 2.

[0034] In the embodiment of the utility model, the process of manufacturing the flexible magnet layer comprises the following steps:

[0035] Neodymium iron boron magnetic powder and Excofle 00-30 silica gel solution are mixed into a mixed solution according to a mass ratio of 2:1, the mixed solution is poured into the 3*3 square array of square grooves 2 on the lower mold 1 of the magnet layer, each square groove 2 has a size of 4mm*4mm and a depth of 3mm, the left and right intervals between the square grooves 2 are 4.5mm, and the front and rear intervals are 7.5mm; then vacuumizing treatment is carried out, a Fujihara oil-free vacuum pump is used for operation, and then the mold is placed in a drying box (a model of Lichen Science and Technology electric heating constant temperature drying box, and the setting temperature is 40C°) for drying for 5 minutes to form a semi-liquid state;

[0036] Then the excess mixture on the surface of the mold is removed, a layer of Excofle 00-30 silica gel solution is poured again, the upper mold 3 of the magnet layer is combined with the lower mold 1 of the magnet layer to be fixed, and then the mold is placed in a drying box for curing for 2 hours;

[0037] After curing, the flexible magnet layer is taken out of the mold, the upper surface of the flexible magnet layer has flexible magnets 11, and the lower surface has a cross-shaped hollow structure 10 embedded inward corresponding to the flexible magnets 11;

[0038] Finally, the flexible magnets 11 are subjected to magnetizing operation to have magnetic field characteristics.

[0039] Referring to Figure 5 As shown in (a)-(b), in the embodiment of the utility model, the elastic layer mold includes an elastic layer lower mold 5 and an elastic layer upper mold 7, and the inner surfaces of the elastic layer lower mold 5 and the elastic layer upper mold 7 are respectively arrayed with a plurality of one-to-one corresponding lower spring fixing columns 6 and upper spring fixing columns 8.

[0040] In the embodiment of the utility model, the process of making the elastic layer includes the following steps:

[0041] A spring 13 is placed on each lower spring fixing column 6 of the elastic layer lower mold 5, the elastic layer upper mold 7 is combined with the elastic layer lower mold 5 to be fixed, and the upper ends of the springs 13 are respectively fixed through the corresponding upper spring fixing columns 8;

[0042] The silica gel liquid is poured into the cavity through the pouring hole provided on the elastic layer upper mold 7;

[0043] Curing forming. The lowermost row of the sensor array is S1-S3, the middle row is S4-S6, and the uppermost row is S7-S9, wherein the magnet, the spring and the Hall sensor jointly act to realize the force sensing function.

[0044] The utility model discloses the advantage lies in, 1) extensible flexible sensing, analog human hand tactile sensation perception, 2) wide force measurement range and high sensitivity: through the optimization magnet hardness and add spring layer, make sensor have extensive force measurement range, normal force measurement range is up to 0~16N, and minimum resolution is 10mN, can accurately detect tiny force change. Tangential force measurement range is -7N to 7N, simultaneously has 57.625 1N-high sensitivity, and it is superior to the flexible sensing of current.

[0045] The above merely describes the embodiments of the utility model, and is not used to limit the protection scope of the utility model. Any modification, equivalent replacement, improvement, extension etc. within the spirit and principle of the utility model are included in the protection scope of the utility model.

Claims

1. A three-dimensional arrayed magneto-tactile sensor, characterized by, The flexible magnet layer is deformed by external pressure to change the magnetic field intensity around, the flexible circuit board layer measures the external force by sensing the magnetic field change of the flexible magnet layer, and the elastic layer is used for expanding the external force measurement range of the flexible circuit board layer.

2. The three-dimensional array magnetic haptic sensor of claim 1, wherein, The flexible magnet layer comprises a top layer flexible body (12) and a plurality of flexible magnets (11) embedded in the top layer flexible body (12), the flexible magnets (11) are used as contacts and can be deformed by external pressure, and then the magnetic field intensity around is changed.

3. The three-dimensional arrayed magneto-tactile sensor according to claim 2, wherein, The front surface of the flexible magnet (11) is a square structure protruding on the upper surface of the top layer flexible body (12), and the bottom surface of the flexible magnet (11) is a cross hollow structure (10) recessed on the lower surface of the top layer flexible body (12).

4. The three-dimensional array magnetic haptic sensor of claim 2, wherein, The elastic layer comprises a middle layer flexible body (14) and a plurality of springs (13) embedded in the middle layer flexible body (14).

5. The three-dimensional array magnetic haptic sensor of claim 2, wherein, The flexible circuit board layer comprises a bottom layer flexible body (17) and a flexible hard brush circuit board (16) embedded above the bottom layer flexible body (17), and a plurality of chips (15) corresponding to the flexible magnets (11) are arranged on the flexible hard brush circuit board (16).

6. The three-dimensional array magnetic haptic sensor of claim 5, wherein, The chip (15) is a Hall sensor, and a plurality of Hall sensors are arranged in a square array.

Images