Flexible magnetic tactile sensor capable of sensing multiple parameters, preparation method and detection method

Abstract

The invention discloses a flexible magnetic tactile sensor capable of sensing multiple parameters, a preparation method and a detection method, the flexible magnetic tactile sensor comprises a flexible contact layer, an elastic substrate layer and a magnetic sensor layer, the flexible contact layer is arranged on the upper side of the elastic substrate layer, and the flexible contact layer comprises a magnetic film; the magnetic film comprises more than two sub-regions containing hard magnetic particles and more than two sub-regions containing soft and hard magnetic particles, the sub-regions containing the hard magnetic particles and the sub-regions containing the soft and hard magnetic particles are alternately distributed, the magnetic sensor layer is arranged on the lower side of the elastic substrate layer or embedded into the elastic substrate layer, and the magnetic sensor layer comprises a plurality of magnetic sensors. And the plurality of magnetic sensors are arranged in one-to-one correspondence with the plurality of sub-regions of the magnetic film. The composite particle magnetoelastomer is prepared by selecting the hard magnetic particles, the soft magnetic particles and the organic high polymer, force / heat information decoupling is completed from the two aspects of array layout design and signal processing, high-sensitivity measurement of force information is achieved, temperature information can be solved, and the composite particle magnetoelastomer has certain application potential in multiple fields.

Description

Technical Field

[0001] The present invention relates to the technical field of flexible tactile sensors, and specifically discloses a flexible magnetic tactile sensor capable of sensing multiple parameters, a preparation method thereof, and a detection method thereof. Background Art

[0002] A large number of receptors are distributed in the human skin to provide rich tactile feedback for people, enabling humans to not only dynamically adjust the finger posture and contact force, accurately identify, grasp, and manipulate objects, but also analyze the surface texture features, material features, etc. of objects. Tactile sensors with tactile perception performance similar to that of the human skin can not only provide sliding feedback for robots, improve the motion accuracy and sensitivity, and enhance the interactivity, adaptability, and intelligence of the component design and performance regulation of robots, but also have broad application prospects in advanced medical treatment, virtual reality, and other fields.

[0003] The core of a flexible tactile sensor is to convert mechanical interaction into electrical signals that can be interpreted by a digital controller. At present, researchers have developed a series of flexible tactile sensors based on piezoresistive, piezocapacitive, piezoelectric, and triboelectric measurement principles based on flexible electronic technology and research on metal nanomaterials, two-dimensional conductive materials, hydrogels, etc., and have shown excellent performance of high-precision perception and fast response. However, with the further improvement of the requirements for sensor performance, the complexity inside the sensor device is continuously increasing, posing challenges to the stability guarantee of the device.

[0004] A magnetic tactile sensor usually consists of a magnetic source that generates a magnetic field signal and a magnetic sensor that detects the magnetic field signal, and has the advantages of high sensitivity, small hysteresis, low power consumption, easy implementation of three-dimensional detection and remote measurement, etc. Moreover, the magnetic field can penetrate organisms and water bodies, and the magnetic field intensity will not be lost during this process, having the advantage of wireless penetration. Existing flexible magnetic sensors have achieved highly sensitive detection of force and three-dimensional force decoupling through the use of flexible magnetic materials and microstructural design and magnetization strategies, but there is still a lack of research on the measurement of other parameters such as temperature, which brings certain limitations to the application of flexible magnetic tactile sensors in fields such as bionic robots. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a flexible magnetic tactile sensor capable of sensing multiple parameters that can not only achieve highly sensitive measurement of force information but also solve temperature information.

[0006] The present invention further provides a preparation method for the above-mentioned flexible magnetic tactile sensor capable of sensing multiple parameters.

[0007] The present invention further provides a detection method for detecting force information and temperature information using the above-mentioned flexible magnetic tactile sensor capable of sensing multiple parameters.

[0008] To solve the above technical problems, the present invention adopts the following technical solutions:

[0009] A flexible magnetic tactile sensor capable of sensing multiple parameters, comprising a flexible contact layer, an elastic base layer, and a magnetic sensor layer. The flexible contact layer is disposed on the upper side of the elastic base layer. The flexible contact layer includes a magnetic film. The magnetic film includes two or more sub-regions containing hard magnetic particles and two or more sub-regions containing both hard and soft magnetic particles. The sub-regions containing hard magnetic particles and the sub-regions containing both hard and soft magnetic particles are alternately distributed. The magnetic sensor layer is disposed on the lower side of the elastic base layer or embedded inside the elastic base layer. The magnetic sensor layer includes a plurality of magnetic sensors, and the plurality of magnetic sensors are arranged in one-to-one correspondence with the plurality of sub-regions of the magnetic film.

[0010] As a further preference for the above technical solution:

[0011] The hard magnetic particles are NdFeB particles, which have a high magnetic energy product, good thermal stability, and good compatibility with various polymer matrices (such as resins, rubbers, etc.);

[0012] And / or, the soft magnetic particles in the hard and soft magnetic particles are Fe₃O₄ particles, whose DC magnetization response generated under the excitation of a static magnetic field has excellent temperature sensitivity, and the hard magnetic particles in the hard and soft magnetic particles are also NdFeB particles;

[0013] And / or, the elastic base layer is made of a flexible and stretchable organic polymer material (such as Ecoflex silicone, a platinum-catalyzed silicone produced by Smooth-On, USA, which has characteristics such as ultra-softness, high elasticity, and low viscosity);

[0014] And / or, the magnetic sensor adopts a Hall element (such as MLX90393, a high-performance three-axis Hall effect sensor developed by Melexis), and the Hall element includes a Hall element body and a flexible printed circuit board (fPCB board), which can better fit with the magnetoelastic body and also improve the conformal ability of the flexible magnetic tactile sensor, enabling the flexible magnetic tactile sensor to be better installed on non-planar surfaces such as mechanical fingertips. Preferably, a single-chip microcomputer is selected to connect to the Hall element for detecting the output signal of the Hall element, and the output signal of the Hall element is amplified and filtered by a preprocessing circuit before being input into a computer through a data card.

[0015] As a further preference for the above technical solution: The cross-sectional shapes of the sub-regions containing hard magnetic particles and the sub-regions containing both hard and soft magnetic particles are the same (such as both square or circular) and the sizes are the same.

[0016] As a further preferred embodiment of the above technical solution: the main body of the magnetic sensor is parallel to the magnetic film and is arranged at the center of each sub-area.

[0017] A method for preparing the above-mentioned flexible magnetic tactile sensor capable of sensing multiple parameters, wherein the preparation process of the magnetic film is as follows:

[0018] First, a hard magnetic particle magnetic elastomer with a micro-pillar array structure is prepared: an uncured organic polymer solution mixed with hard magnetic particles is poured into a micro-pillar array mold, and after vacuum defoaming treatment, it is placed in a uniform magnetic field until it is cured and formed, and the cured elastomer is magnetized along the direction of the cylindrical hole, and then demolded to obtain a hard magnetic particle magnetic elastomer with hard magnetic particles orderly arranged in a specific direction;

[0019] Then, the hard magnetic particle magnetic elastomer is filled with an organic polymer solution mixed with soft magnetic particles, and after solidification, the sub-region containing both soft magnetic particles and hard magnetic particles is obtained; the hard magnetic particle magnetic elastomer is filled with an organic polymer solution without magnetic particles, and after solidification, the sub-region containing hard magnetic particles is obtained;

[0020] Finally, the prepared sub-regions containing hard magnetic particles and the sub-regions containing soft and hard magnetic particles are arranged in an array to obtain a magnetic film.

[0021] As a further optimization of the above technical solution: it specifically comprises the following steps:

[0022] a) Prepare a micro-pillar array mold by 3D printing to facilitate the regulation of the diameter, height and array distribution of the micro-pillar structure, clean the micro-pillar array mold with ethanol and air-dry the surface at room temperature;

[0023] b) Adding NdFeB particles to Ecoflex A and stirring thoroughly, then adding Ecoflex B and stirring thoroughly, pouring into the microcolumn array mold, defoaming in a vacuum box (e.g., evacuating in a vacuum box with a vacuum degree of -0.1 MPa for 10 minutes), and then placing in a structured magnetic field (e.g., a static magnetic field with a magnetic field strength of 0.1 Tesla), and standing at room temperature to wait for solidification;

[0024] c) demolding the cured Ecoflex to obtain an elastomer containing NdFeB particles, placing the elastomer containing NdFeB particles into a magnetizer for magnetization to obtain a magnetic elastomer with hard magnetic particles having magnetic properties;

[0025] d) using Ecoflex without magnetic particles to fill the hard magnetic particle magnetic elastomer prepared in step c), and obtaining a sub-region containing hard magnetic particles after defoaming and curing;

[0026] e), Add Fe₃O₄ particles to Ecoflex A agent and stir well, then add Ecoflex B agent and stir well, and then fill the hard magnetic particle magnetoelastic body prepared in step c). After defoaming and curing, a sub-region containing both soft magnetic particles and hard magnetic particles is obtained;

[0027] f), Assemble the sub-region containing hard magnetic particles prepared in step d) and the sub-region containing both soft and hard magnetic particles prepared in step e) to form a magnetic film. Place corresponding Hall elements at the center positions of each sub-region of the magnetic film, and use Ecoflex without magnetic particles to make an elastic base layer to complete the encapsulation.

[0028] As a further preference of the above technical solution: The volume ratio of monomer Ecoflex A to cross-linking agent Ecoflex B is 1:1. The cured Ecoflex silica gel is not easily adhered to the micro-column array mold, which can reduce the damage to the elastomer during the demolding process.

[0029] As a further preference of the above technical solution: The mass ratio of hard magnetic particles to the uncured organic polymer solution is 1:1 - 3:7 when mixed.

[0030] As a further preference of the above technical solution: The uniform magnetic field is a static magnetic field.

[0031] A detection method for detecting force / temperature information using the above-mentioned flexible magnetic tactile sensor capable of sensing multiple parameters,

[0032] Obtain the magnetic field intensity using the above-mentioned flexible magnetic tactile sensor capable of sensing multiple parameters, and calculate the force and temperature information obtained through the following model respectively:

[0033] The magnetic field intensity B detected by the magnetic sensor is:

[0034]

[0035] In the above formula, n and d are respectively the carrier concentration and thickness of the Hall material, e is the electron charge, I S is the current flowing through the Hall material. When the working current I S is fixed, the Hall voltage V H is positively correlated with the change in the magnetic field intensity B.

[0036] According to the output voltage V h of the Hall element corresponding to the sub-region containing hard magnetic particles, the magnetic field intensity B h solved only contains the term of the change in the magnetic field intensity caused by the external force:

[0037] B h = f H ·H h+f σ ·σ

[0038] In the above formula, f H , f σ are respectively the effective field calculation functions of the magnetization field and stress field of hard magnetic particles, H h is the magnetization field of hard magnetic particles, σ is the strain generated by the magnetoelastic body under the action of external force. According to the relationship between the external force and strain calibrated in the early stage, and the magnetization field intensity of hard magnetic particles, a regression model of the contact force magnitude is constructed, and the force magnitude of the flexible magnetic tactile sensor that can sense multiple parameters can be solved;

[0039] According to the output voltage V of the Hall element corresponding to the sub-region containing hard and soft magnetic particles S The magnetic field intensity Bs obtained by solving only contains the term of the magnetic field intensity change caused by the external force:

[0040] B s = f H ·H h + f σ ·σ + f T ·T

[0041] In the above formula, f T is the effective field calculation function of the temperature field, T is the temperature value. According to the difference principle, through the following formula:

[0042] B s - B h = f T ·T

[0043] And the relationship between the temperature change and magnetic field change calibrated in the early stage, a regression model of the contact temperature magnitude is constructed, and the temperature information of the flexible magnetic tactile sensor that can sense multiple parameters can be solved.

[0044] Compared with the prior art, the advantages of the present invention are as follows:

[0045] The flexible magnetic tactile sensor that can sense multiple parameters disclosed by the present invention as a whole has good stretchability. By adjusting the process parameters, the overall thickness of the sensor can be regulated so that the sensor can maintain good conformal with the installation surface. Among them, the elastic base layer is the application surface of the flexible magnetic tactile sensor. If a split installation is adopted, the separation of the flexible contact layer and the magnetic sensor can be realized, and there is no need for cable connection or direct contact between the two, which can ensure the stability of the magnetic sensor and enable the sensor to be applied to underwater and other scenarios; the present invention selects two kinds of magnetic particles, hard magnetic and soft magnetic, and an organic polymer to prepare a composite particle magnetoelastic body, and decouples the force / heat information from two levels of array layout design and signal processing, not only realizes the high-sensitivity measurement of force information, but also can solve the temperature information, and has certain application potential in many fields such as bionic robots and advanced medical treatment.

[0046] Other features and advantages of the present invention will be described in detail in the following specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 is a schematic three-dimensional structure diagram of the flexible magnetic tactile that can sense multiple parameters of the present invention.

[0048] Figure 2 is a schematic flow chart of the preparation method of the flexible magnetic tactile that can sense multiple parameters of the present invention.

[0049] Figure 3 is a result diagram of the actual pressure measurement of the present invention, and the applied pressure is the positive pressure perpendicular to the surface of the magnetic film.

[0050] Figure 4 is a result diagram of the actual temperature measurement of the present invention.

[0051] Each label in the figure represents:

[0052] 1. Micro-column array mold; 2. Hard magnetic particle magnetoelastic body; 3. Magnetic pole for generating a structural magnetic field; 4. Elastomer without magnetic particles; 5. Soft magnetic particle magnetoelastic body; 6. Elastic base layer; 7. Hall element; 8. Square container; 9. Sub-region containing hard magnetic particles; 10. Sub-region containing both hard and soft magnetic particles. SPECIFIC IMPLEMENTATION MODE

[0053] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0054] In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more, unless otherwise specifically defined.

[0055] In the present invention, unless otherwise clearly specified and defined, terms such as "assembly", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] The following further details the present invention in conjunction with the accompanying drawings of the specification and specific embodiments.

[0057] As Figure 1 and Figure 2 shown, a preparation method of a flexible magnetic tactile sensor capable of sensing multiple parameters in this embodiment includes the following steps:

[0058] a), Design and fabricate a micro-column array mold 1 with a square base side length of 15 mm based on 3D printing. The diameter of the micro-columns on the micro-column array mold 1 is 200 microns. A stereolithography 3D printer is used, and a photosensitive resin is selected. After the mold is printed, it is surface-cleaned with ethanol, and then exposed to ultraviolet light for 30 minutes. Finally, the micro-column array mold 1 is obtained, and then it is placed in a square mold with an inner side length of 15 mm as well;

[0059] b), Prepare a hard magnetic particle magnetoelastic body 2 according to the material ratio: 25 wt% of Ecoflex 00-30A agent, 25 wt% of Ecoflex 00-30B agent, and 50 wt% of neodymium iron boron particles, where the diameter of the neodymium iron boron particles is 5 microns. First, the Ecoflex 00-30A agent and the neodymium iron boron particles are mixed by magnetic stirring at a rotation speed of 2000 revolutions per minute. After mixing for 3 minutes, the Ecoflex 00-30B agent is added and mixed at the same rotation speed for 3 minutes. Then, the mixed material is slowly poured into the square mold containing the micro-column array mold 1, transferred to a vacuum chamber with a vacuum degree of -0.1 megapascal, evacuated for 10 minutes to complete defoaming, and then transferred to a structural magnetic field and left to cure for 6 hours, and then demolded to obtain the cured hard magnetic particle magnetoelastic body 2;

[0060] c), Prepare an elastomer 4 without magnetic particles according to the material ratio: 45 wt% of Ecoflex 00-30A agent, 45 wt% of Ecoflex 00-30B agent, and 10 wt% of 5-viscosity dimethyl silicone oil. After mixing the materials by magnetic stirring at a rotation speed of 2000 revolutions per minute for 3 minutes, the mixed material is slowly poured into the square mold containing the cured hard magnetic particle magnetoelastic body 2 and placed in a vacuum chamber to defoam for 10 minutes, and then left to cure for 6 hours, and then demolded to obtain a sub-region 9 containing hard magnetic particles;

[0061] d) Prepare a soft magnetic particle magnetic elastomer 5 according to the material ratio: 30wt% Ecoflex 00-30A agent, 30wt% Ecoflex00-30B agent, 6.7wt% 5 viscosity dimethyl silicone oil and 33.3wt% ferrosoferric oxide particles, wherein the diameter of the ferrosoferric oxide particles is 100 nanometers. After mixing the materials, stir them magnetically at a speed of 2000 rpm for 3 minutes, then slowly pour the mixed material into a square mold containing the cured hard magnetic particle magnetic elastomer 2 and put it into a vacuum box for defoaming for 10 minutes, then let it stand and cure for 6 hours, and then demold to obtain a sub-region 10 containing soft and hard magnetic particles;

[0062] e) Place two sub-regions 9 containing hard magnetic particles and two sub-regions 10 containing soft and hard magnetic particles into a square container 8 with a side length of 35 mm in a non-adjacent manner, and slowly pour a mixed solution having the same material ratio as the elastomer 4 without magnetic particles into the square container 8, so that the solution covers the soft magnetic particle magnetic elastomer 5 and the hard magnetic particle magnetic elastomer 2 by 5 mm, and then place the square container 8 into a vacuum box for defoaming and then stand for 6 hours to solidify;

[0063] f) Apply room temperature adhesive ELASTOSIL E43 on the surface of the Hall element 7. The high-performance silicone material brand produced by WackerChemie AG of Germany is widely used in many fields such as industry, construction, automobiles, medical treatment and consumer products. Attach the Hall element 7 to the center of the corresponding magnetic film sub-area, that is, the position where the output voltage signal of the Hall element 7 is the largest. Then, slowly pour a mixed solution with the same material ratio as the elastomer 4 without magnetic particles into the gap between the soft magnetic particle magnetic elastomer 5, the hard magnetic particle magnetic elastomer 2 and the PCB board. After curing, an elastic base layer 6 is obtained. After demolding, the preparation of the sensor is completed. The structure of the obtained flexible magnetic tactile sensor that can perceive multiple parameters is as shown in FIG. Figure 1 shown.

[0064] Preferably, the Hall element 7 is a linear Hall element, the element input is the magnetic induction intensity, and the output is a voltage proportional to the input.

[0065] Preferably, the organic polymer is Ecoflex silicone, which has a low elastic modulus and large deformation characteristics, can improve the force sensitivity of the sensor and achieve excellent perception of tiny forces.

[0066] Preferably, the PCB circuit board can be an fPCB board manufactured based on flexible electronic printing technology, which can not only better adhere to the magnetoelastic body (including the soft magnetic particle magnetoelastic body 5 and the hard magnetic particle magnetoelastic body 2), but also improve the conformal ability of the flexible magnetic tactile sensor, enabling the flexible magnetic tactile sensor to be better installed on non-planar surfaces such as the fingertips of mechanical fingers.

[0067] Figure 3 Shows the relationship between the Hall element signal and the load during the actual pressure test of the present invention. The signal intensity after superimposing the output signal of the Hall element corresponding to the sub-region 9 containing hard magnetic particles and the output signal of the Hall element corresponding to the sub-region 10 containing both hard and soft magnetic particles is used as the input to construct a regression model for the magnitude of the contact force to solve for the magnitude of the contact force.

[0068] Figure 4 Shows the relationship between the Hall element signal and the load during the actual temperature test of the present invention. After differentiating the output signal of the Hall element corresponding to the sub-region 9 containing hard magnetic particles and the output signal of the Hall element corresponding to the sub-region 10 containing both hard and soft magnetic particles, a regression model for the magnitude of the contact temperature is constructed based on the relationship between the temperature and the differential signal intensity to solve for the magnitude of the contact temperature.

[0069] Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make many possible changes and modifications to the technical solution of the present invention, or modify it into an equivalent embodiment with equivalent changes, without departing from the scope of the technical solution of the present invention. Therefore, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. A flexible magnetic tactile sensor capable of sensing multiple parameters, characterized in that: It includes a flexible contact layer, an elastic base layer (6) and a magnetic sensor layer. The flexible contact layer is disposed on the upper side of the elastic base layer (6). The flexible contact layer includes a magnetic film. The magnetic film includes two or more sub-regions (9) containing hard magnetic particles and two or more sub-regions (10) containing both hard and soft magnetic particles. The sub-regions (9) containing hard magnetic particles and the sub-regions (10) containing both hard and soft magnetic particles are alternately distributed. The magnetic sensor layer is disposed on the lower side of the elastic base layer (6) or embedded inside the elastic base layer (6). The magnetic sensor layer includes a plurality of magnetic sensors, and the plurality of magnetic sensors are arranged in one-to-one correspondence with the plurality of sub-regions of the magnetic film.

2. The flexible magnetic tactile sensor capable of sensing multiple parameters according to claim 1, wherein: The hard magnetic particles are NdFeB particles; And / or, the soft magnetic particles in the hard and soft magnetic particles are Fe₃O₄ particles, and the hard magnetic particles are NdFeB particles; And / or, the elastic base layer (6) is made of a flexible and stretchable organic polymer material; And / or, the magnetic sensor uses a Hall element (7), and the Hall element (7) includes a Hall element body and a flexible printed circuit board.

3. The flexible magnetic tactile sensor capable of perceiving multiple parameters according to claim 1, wherein: The cross-sectional shapes and sizes of the sub-regions (9) containing hard magnetic particles and the sub-regions (10) containing both hard and soft magnetic particles are the same.

4. The flexible magnetic tactile sensor capable of perceiving multiple parameters according to claim 3, characterized in that: The main body of the magnetic sensor is parallel to the magnetic film and is arranged at the central position of each sub-region.

5. A method for preparing a flexible magnetic tactile sensor capable of sensing multiple parameters according to any one of claims 1 to 4, characterized in that: The preparation process of the magnetic film is as follows: First, prepare a hard magnetic particle magnetoelastic body (2) with a micro-column array structure: Pour an uncured organic polymer solution mixed with hard magnetic particles into a micro-column array mold (1), after vacuum degassing treatment, place it in a uniform magnetic field until it is cured and formed. After magnetizing the cured elastic body along the direction of the cylindrical hole, demold to obtain a hard magnetic particle magnetoelastic body (2) with hard magnetic particles arranged orderly in a specific direction; Then, fill the hard magnetic particle magnetoelastic body (2) with an organic polymer solution mixed with soft magnetic particles, and after curing, obtain the sub-regions (10) containing both soft and hard magnetic particles; fill the hard magnetic particle magnetoelastic body (2) with an organic polymer solution without magnetic particles, and after curing, obtain the sub-regions (9) containing hard magnetic particles; Finally, perform array arrangement on the prepared sub-regions (9) containing hard magnetic particles and sub-regions (10) containing both hard and soft magnetic particles to obtain a magnetic film.

6. The preparation method of the flexible magnetic tactile sensor capable of sensing multiple parameters according to claim 5, characterized in that: Specifically, it includes the following steps: a), Prepare a micro-column array mold (1) by 3D printing, clean the micro-column array mold (1) with ethanol and air-dry the surface at room temperature; b), Add neodymium iron boron particles to Ecoflex A agent and stir well, then add Ecoflex B agent and stir well, and pour it into the micro-column array mold (1). After vacuum box degassing treatment, place it in a structured magnetic field and wait for curing at room temperature; c), Demold the cured Ecoflex to obtain an elastic body containing neodymium iron boron particles, and place the elastic body containing neodymium iron boron particles in a magnetizer for magnetization to obtain a magnetic hard magnetic particle magnetoelastic body (2); d) using Ecoflex without magnetic particles to fill the hard magnetic particle magnetic elastomer (2) prepared in step c), and obtaining the sub-region (9) containing hard magnetic particles after defoaming and curing; e) adding ferrosoferric oxide particles to Ecoflex A and stirring thoroughly, then adding Ecoflex B and stirring thoroughly, and then filling the hard magnetic particle magnetic elastomer (2) prepared in step c), and after defoaming and curing, obtaining the sub-region (10) containing both soft magnetic particles and hard magnetic particles; f), assembling the sub-region (9) containing hard magnetic particles prepared in step d) and the sub-region (10) containing soft and hard magnetic particles prepared in step e) to form a magnetic film, placing a corresponding Hall element (7) at the center of each sub-region of the magnetic film, and using Ecoflex that does not contain magnetic particles to make an elastic base layer (6) to complete the packaging.

7. The preparation method of the flexible magnetic tactile sensor capable of perceiving multiple parameters according to claim 6, wherein: The volume ratio of monomer Ecoflex A to crosslinker Ecoflex B is 1:

1.

8. The preparation method of the flexible magnetic tactile sensor capable of sensing multiple parameters according to claim 5, characterized in that: The mass ratio of the hard magnetic particles when mixed with the uncured organic polymer solution is 1:1 to 3:

7.

9. The preparation method of the flexible magnetic tactile sensor capable of sensing multiple parameters according to claim 5, characterized in that: The uniform magnetic field is a static magnetic field.

10. A method for detecting force / temperature information using a flexible magnetic tactile sensor capable of perceiving multiple parameters according to any one of claims 1 to 4, characterized in that: The magnetic field strength is obtained by using the magnetic sensor, and the force and temperature information are calculated by the following models respectively: The magnetic field strength B detected by the magnetic sensor is: In the above formula, n and d are the carrier concentration and thickness of the Hall material respectively, e is the electron charge, and I S is the current flowing through the Hall material. When the working current I S is fixed, the Hall voltage V H is positively correlated with the change in the magnetic field strength B; According to the output voltage V of the Hall element (7) corresponding to the sub-region (9) containing hard magnetic particles h The magnetic field strength B obtained by solution h Only includes the magnetic field strength change term caused by the external force B h = f H · H h + f σ · σ In the above formula, f H and f σ are respectively the effective field calculation functions of the magnetization field and the stress field of the hard magnetic particles. H h is the magnetization field of the hard magnetic particles, and σ is the strain generated by the magnetoelastic body under the action of an external force. According to the relationship between the external force and the strain calibrated in the early stage, and the magnetization field intensity of the hard magnetic particles, a regression model for the magnitude of the contact force is constructed, and the magnitude of the force on the flexible magnetic tactile sensor that can sense multiple parameters can be solved; Based on the output voltage V of the Hall element (7) corresponding to the sub-region (10) containing soft and hard magnetic particles S The obtained magnetic field strength Bs only includes the term of the change in magnetic field strength caused by the external force B s = f H ·H h + f σ ·σ + f T ·T In the above formula, f T is the effective field calculation function of the temperature field, T is the temperature value. According to the difference principle, through the following formula: B s -B h = f T ·T As well as the relationship between the temperature change and the magnetic field change calibrated in the early stage, a contact temperature regression model is constructed to obtain the temperature information of the flexible magnetic tactile sensor that can perceive multiple parameters.

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