Multi-dimensional force tactile perception electronic skin and preparation method thereof

Abstract

Disclosed are a multi-dimensional force tactile perception electronic skin and a preparation method thereof. In the method, a plurality of TMR elements are arrayed on a flexible printed circuit board; a silicone rubber base is attached to the flexible printed circuit board with the plurality of TMR elements arrayed thereon; a neodymium iron boron-PDMS magnet block is prepared, the neodymium iron boron-PDMS magnet block being mixed from neodymium iron boron magnetic particles and polydimethylsiloxane; a PDMS protective layer is prepared, a main agent and a curing agent of the PDMS are mixed and stirred at a ratio of 5:1, and then placed in an ultrasonic oscillator for oscillation, and then poured into a mold for the protective layer, and then placed in a vacuum box for vacuumizing treatment, and then subjected to ultrasonic oscillation, and finally placed in a curing box for curing and cooling to obtain the PDMS protective layer; and the PDMS protective layer and the neodymium iron boron-PDMS magnet block are adhered through a PDMS prepolymer and then laminated on the silicone rubber base, so that the neodymium iron boron-PDMS magnet block is located between the silicone rubber base and the PDMS protective layer.

Description

Technical Field

[0001] This invention belongs to the field of electronic skin, specifically a multidimensional force-tactile sensing electronic skin and its preparation method. Background Technology

[0002] Robots are playing an increasingly important role in human life, moving from laboratories to factories and even into homes. A key indicator of a robot's level of intelligence in human life is its operational capabilities. Tactile sensors, as the medium for robots to interact with the outside world, enable robots to achieve self-perception and feedback, better performing tasks such as object recognition, operational status judgment, and collision detection. In various daily tasks, sensors are required not only to sense pressure but also shear force and even torque. Furthermore, sensors should possess a certain degree of flexibility and extensibility to provide skin-like cushioning and protection. Existing magnetic films are typically monolithic films composed of magnetic particles and polymers. These films often suffer from uneven magnetization and weak magnetic field strength, leading to poor positioning accuracy, low sensitivity, and low resolution in arrayed sensors. The uneven and complex distribution of the magnetic field in continuous magnetic films also complicates sensor calibration. Currently, electronic skin suffers from problems such as typically only being able to detect pressure in a single direction, low sensitivity, difficult calibration, and high manufacturing requirements.

[0003] The information disclosed in the background section is only intended to enhance the understanding of the background of the present invention, and therefore may contain information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention proposes a multidimensional force-tactile sensing electronic skin and its preparation method, which has the ability to recognize spatial multidimensional force dynamics and statics, and is highly sensitive and flexible.

[0005] The objective of this invention is achieved through the following technical solution: a method for preparing a multidimensional force-tactile sensing electronic skin includes:

[0006] Multiple TMR components are arrayed on a flexible printed circuit board;

[0007] A silicone rubber substrate is bonded to a flexible printed circuit board containing an array of multiple TMR elements;

[0008] A neodymium iron boron-PDMS magnet block was prepared, wherein the neodymium iron boron-PDMS magnet block was composed of neodymium iron boron magnetic particles and polydimethylsiloxane;

[0009] To prepare the PDMS protective layer, the PDMS main agent and curing agent were mixed and stirred at a ratio of 5:1, and then poured into a mold for the protective layer after being vibrated in an ultrasonic oscillator. The mixture was then placed in a vacuum chamber for vacuum treatment, followed by ultrasonic vibration, and finally placed in a curing chamber for curing and cooling to obtain the PDMS protective layer.

[0010] The PDMS protective layer and the NdFeB-PDMS magnet block are bonded together using PDMS prepolymer and then stacked on the silicone rubber substrate, so that the NdFeB-PDMS magnet block is located between the silicone rubber substrate and the PDMS protective layer.

[0011] In the preparation method of the multidimensional force-tactile sensing electronic skin, in the preparation of the neodymium iron boron-PDMS magnet block, neodymium iron boron magnetic particles and PDMS prepolymer are mixed in a ratio of 2:1 and stirred in an ultrasonic stirrer for 30-60 minutes to obtain neodymium iron boron-PDMS prepolymer; a layer of PDMS release agent is sprayed into the magnetic block mold, and then the neodymium iron boron-PDMS prepolymer is poured into the magnetic block mold. The magnetic block mold is placed in a constant magnetic field space device composed of two permanent magnets, and then the entire device is placed in a high-temperature curing oven for curing and cooling. Finally, magnetization is performed along the thickness direction under the magnetic field space.

[0012] In the preparation method of the multidimensional force-tactile sensing electronic skin, the magnetic block mold is placed in a constant 200mT magnetic field space device composed of two permanent magnets. Then the entire device is placed in a high-temperature curing chamber and cured at 80°C for 2 hours. After that, it is cooled at room temperature for 2 hours. Finally, it is magnetized along the thickness direction in a 5T magnetic field space.

[0013] In the preparation method of the multidimensional force-tactile sensing electronic skin, PDMS main agent and curing agent are mixed at a ratio of 5:1, then stirred with a glass rod for 10 minutes, followed by ultrasonic oscillation for 2 minutes. Then, PDMS is poured into the upper protective layer mold, and the whole thing is placed in a vacuum chamber for vacuum treatment at -0.09MPa for 2 minutes. After that, ultrasonic oscillation is performed for 5 minutes. Finally, it is placed in a high-temperature curing chamber and cured at 80°C for 2 hours. Finally, it is cooled at room temperature for 2 hours.

[0014] In the preparation method of the multidimensional force-tactile sensing electronic skin, the PDMS prepolymer is obtained by mixing PDMS main agent and curing agent in a ratio of 8:1 and stirring in an ultrasonic mixer.

[0015] A multidimensional force-tactile sensing electronic skin is prepared according to the aforementioned method for preparing a multidimensional force-tactile sensing electronic skin.

[0016] In the aforementioned multidimensional force-tactile sensing electronic skin, 16 TMR elements are distributed in a 4×4 array on a flexible printed circuit board.

[0017] In the aforementioned multidimensional force-tactile sensing electronic skin, the neodymium iron boron-PDMS magnet block has a size of 3mm×2.5mm×2mm, the silicone rubber substrate has a thickness of 4mm-5mm, and the TMR element is in the Z-axis magnetic sensing direction with a size of 2.95mm×1.65mm×1.45mm.

[0018] In the aforementioned multidimensional force-tactile sensing electronic skin, the neodymium iron boron magnetic particles have a particle size of 1–2 μm.

[0019] In the aforementioned multidimensional force-tactile sensing electronic skin, the neodymium iron boron-PDMS magnet blocks are arranged in an alternating N and S phase configuration.

[0020] Compared with existing technologies, this invention has the following advantages: This invention utilizes neodymium magnet powder with high remanence and low intrinsic coercivity, and PDMS with high elastic modulus to form magnetic blocks as a magnetic field source. High-sensitivity, low-power, and temperature-insensitive TMR elements are used as sensing elements to form an electronic skin. Based on the output voltage characteristics and magnitude of the magnetic sensing elements under different forces, force / torque recognition and positioning are achieved. Sixteen TMR elements are soldered onto an FPCB in a 4×4h configuration, giving the sensor a certain degree of flexibility, facilitating its attachment to a robotic arm. Arranging magnetic blocks on the TMR elements ensures that each TMR element is within a high magnetic field variation range, thereby improving the sensitivity and resolution of the tactile sensor. The arrangement of individual magnetic blocks simplifies the TMR sensing model, making it easier to calibrate without considering other stray magnetic fields. Based on the continuity of the PDMS protective layer, even if an external force is applied between two magnetic blocks, adjacent magnetic blocks will deflect to a certain extent, thus achieving higher resolution force positioning. The sensor uses a flexible and stretchable TPU substrate, which can be easily attached to various curved surfaces. The magnetic block and the PDMS protective layer are connected by PDMS prepolymer. Since the polymer has the same functional groups, the magnetic block and the PDMS protective layer can be tightly connected. Attached Figure Description

[0021] Various other advantages and benefits of the present invention will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0022] In the attached diagram:

[0023] Figure 1 This is a schematic diagram of the entire structure of the electronic skin;

[0024] Figure 2 This is a schematic diagram showing the change in the output voltage of the TMR element when the electronic skin is subjected to positive pressure;

[0025] Figure 3 This is a schematic diagram showing the change in the output voltage of the TMR element when the electronic skin is subjected to a tangential force along the Y-axis.

[0026] Figure 4 This is a schematic diagram showing the change in the output voltage of the TMR element when the electronic skin is subjected to a tangential force along the X-axis.

[0027] Figure 5 This is a schematic diagram showing the change in the output voltage of the TMR element when the electronic skin is subjected to in-plane torque.

[0028] Figure 6 This is a schematic diagram of the arrangement of neodymium magnet powder-PDMS magnetic blocks in electronic skin;

[0029] Figure 7 This is a schematic diagram of the arrangement of TMR components in electronic skin.

[0030] The present invention will be further explained below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0031] Specific embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While specific embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art.

[0032] It should be noted that certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that different terms may be used to refer to the same component. This specification and claims do not distinguish components based on differences in terminology, but rather on differences in function. The terms "comprising" or "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising but not limited to." The following descriptions are preferred embodiments for carrying out the invention; however, these descriptions are for the purpose of understanding the general principles of the specification and are not intended to limit the scope of the invention. The scope of protection of this invention is determined by the appended claims.

[0033] To facilitate understanding of the embodiments of the present invention, further explanations and descriptions will be provided below with reference to the accompanying drawings and specific embodiments. The accompanying drawings do not constitute a limitation on the embodiments of the present invention.

[0034] In one embodiment, such as Figures 1 to 7 As shown, a method for preparing a multidimensional force-tactile sensing electronic skin includes,

[0035] Multiple TMR elements 4 are arrayed on the flexible printed circuit board 5;

[0036] A silicone rubber substrate 3 is bonded to a flexible printed circuit board 5 on which multiple TMR elements 4 are arrayed;

[0037] A neodymium iron boron-PDMS magnet block 2 is prepared, wherein the neodymium iron boron-PDMS magnet block 2 is composed of neodymium iron boron magnetic particles and polydimethylsiloxane;

[0038] To prepare PDMS protective layer 1, the PDMS main agent and curing agent were mixed and stirred at a ratio of 5:1, and then poured into the mold of the protective layer after being vibrated in an ultrasonic oscillator. After that, they were placed in a vacuum chamber for vacuum treatment, followed by ultrasonic vibration, and finally placed in a curing chamber for curing and cooling to obtain PDMS protective layer 1.

[0039] The PDMS protective layer 1 and the NdFeB-PDMS magnet block 2 are bonded together using PDMS prepolymer and then stacked on the silicone rubber substrate 3, so that the NdFeB-PDMS magnet block 2 is located between the silicone rubber substrate 3 and the PDMS protective layer.

[0040] In a preferred embodiment of the method for preparing a multidimensional force-tactile sensing electronic skin, in the preparation of the neodymium iron boron-PDMS magnet block 2, neodymium iron boron magnetic particles and PDMS prepolymer are mixed in a 2:1 ratio and stirred in an ultrasonic mixer for 30-60 minutes to obtain the neodymium iron boron-PDMS prepolymer; a layer of PDMS release agent is sprayed into the magnetic block mold, and then the neodymium iron boron-PDMS prepolymer is poured into the magnetic block mold. The magnetic block mold is placed in a constant magnetic field space device composed of two permanent magnets, and then the entire device is placed in a high-temperature curing oven for curing and cooling. Finally, magnetization is performed along the thickness direction in the magnetic field space.

[0041] In a preferred embodiment of the method for preparing a multidimensional force-tactile sensing electronic skin, a magnetic block mold is placed in a space device with a constant magnetic field of 200mT composed of two permanent magnets. Then, the entire device is placed in a high-temperature curing chamber and cured at a constant temperature of 80°C for 2 hours. After that, it is cooled at room temperature for 2 hours. Finally, it is magnetized along the thickness direction in a magnetic field space of 5T.

[0042] In a preferred embodiment of the method for preparing a multidimensional force-tactile sensing electronic skin, the PDMS main agent and curing agent are mixed at a ratio of 5:1, stirred with a glass rod for 10 minutes, then placed in an ultrasonic oscillator for 2 minutes, and then the PDMS is poured into the upper protective layer mold. The whole thing is then placed in a vacuum chamber for vacuum treatment at -0.09 MPa for 2 minutes, followed by ultrasonic oscillation for 5 minutes, and finally placed in a high-temperature curing chamber for constant temperature curing at 80°C for 2 hours, and finally cooled at room temperature for 2 hours.

[0043] In a preferred embodiment of the method for preparing a multidimensional force-tactile sensing electronic skin, the PDMS prepolymer is obtained by mixing a PDMS main agent and a curing agent in a ratio of 8:1 and stirring the mixture in an ultrasonic mixer.

[0044] A multidimensional force-tactile sensing electronic skin is prepared according to the aforementioned method for preparing a multidimensional force-tactile sensing electronic skin.

[0045] In the aforementioned multidimensional force-tactile sensing electronic skin, 16 TMR elements 4 are distributed in a 4×4 array on a flexible printed circuit board 5.

[0046] In the aforementioned multidimensional force-tactile sensing electronic skin, the neodymium iron boron-PDMS magnet block 2 has a size of 3mm×2.5mm×2mm, the silicone rubber substrate 3 has a thickness of 4mm-5mm, and the TMR element 4 is in the Z-axis magnetic sensing direction with a size of 2.95mm×1.65mm×1.45mm.

[0047] In the aforementioned multidimensional force-tactile sensing electronic skin, the neodymium iron boron magnetic particles have a particle size of 1–2 μm.

[0048] In the aforementioned multidimensional force-tactile sensing electronic skin, the neodymium iron boron-PDMS magnet block 2 is arranged in an alternating N and S phase configuration.

[0049] In one embodiment, the multidimensional force-tactile sensing electronic skin consists of five parts: a PDMS protective layer 1, a neodymium iron boron-PDMS magnetic block, a silicone rubber substrate 3, a TMR element 4, and a flexible printed circuit board 5. It can fit well into the fingertips and palm of a robotic hand, giving the robot the ability to sensitively perceive changes in the manipulated object. Simultaneously, it can also detect the edge shape and hardness of the object. The 4×4 TMR element 4 in the lower layer of the electronic skin can detect weak magnetic field changes, converting them into changes in magnetoresistance value through the tunneling magnetoresistance effect, and then converting them into an electrical signal for output via a bridge circuit. The silicone rubber substrate 3 in the middle layer serves as a buffer layer to protect the sensor and the force-displacement conversion matrix. The range and resolution of the sensor can be changed by altering the elastic modulus of the matrix according to actual needs. When an external force acts on the PDMS protective layer, the PDMS protective layer and the magnetic blocks embedded in it move together, providing a changing magnetic field for the TMR magnetic sensing element.

[0050] In one embodiment, the multidimensional force-sensitive electronic skin includes a PDMS protective layer, a neodymium iron boron-PDMS magnet block 2, a silicone rubber Ecoflex 00-30 intermediate layer, TMR elements 4, and an FPCB. Sixteen TMR elements 4 are arranged in a 4×4 array on the flexible PCB; the silicone rubber Ecoflex 00-30 intermediate layer is attached above the flexible PCB; the PDMS protective layer and the magnet block together constitute the upper layer of the sensor. Based on neodymium magnet powder, polydimethylsiloxane, and TMR magnetic sensing elements, an electronic skin with force positioning, multidimensional force measurement, dynamic and static sensing, and high-sensitivity detection is designed through arraying. When different external forces act on the electronic skin, the magnetic blocks will undergo spatial displacement, thereby changing the distribution of the spatial magnetic field. The Z-axis tunnel magnetoresistive element serves as the detection part; changes in the magnetic field cause changes in its internal magnetoresistive resistance, which is converted into an electrical signal by a bridge circuit for output. Magnetic sensing elements at fixed positions exhibit different change characteristics. By comprehensively judging the change trends and values ​​of the sixteen elements, the magnitude, position, and direction of multidimensional forces in space are identified. This invention has the advantages of spatial multidimensional force dynamic and static recognition, high sensitivity, and good flexibility.

[0051] The neodymium iron boron-PDMS magnetic block is composed of neodymium iron boron particles and polydimethylsiloxane in a mass ratio of 2:1, with dimensions of 3mm × 2.5mm × 2mm. The multidimensional force-tactile sensing electronic skin can sense skin surface pressure, shear force, and torque perpendicular to the surface. The thickness of the Ecoflex 00-30 interlayer is 4mm-5mm.

[0052] The preparation method of the NdFeB-PDMS magnetic block includes the following steps: NdFeB magnetic particles and PDMS prepolymer are mixed in a 2:1 ratio and stirred in an ultrasonic stirrer for 30-60 minutes to obtain NdFeB-PDMS prepolymer; a layer of PDMS release agent is sprayed into the magnetic block mold, and then the NdFeB-PDMS prepolymer is poured into the mold. The mold is placed in a space device with a constant magnetic field of 200mT composed of two permanent magnets, and then the entire device is placed in a high-temperature curing oven and cured at 80°C for 2 hours. Then it is cooled at room temperature for 2 hours. Finally, it is magnetized along the thickness direction in a 5T magnetic field space. The particle size of the NdFeB magnetic particles is 1-2μm, which is 2000-mesh NdFeB magnet powder.

[0053] The fabrication process of the PDMS protective layer includes the following steps: The PDMS base agent and curing agent are mixed at a ratio of 5:1, then stirred with a glass rod for 10 minutes, followed by ultrasonic vibration for 2 minutes. The PDMS is then poured into a mold for the upper protective layer, and the entire assembly is placed in a vacuum chamber for vacuum treatment at -0.09 MPa for 2 minutes. Afterward, ultrasonic vibration is performed for 5 minutes, and finally, the mixture is placed in a high-temperature curing chamber and cured at 80°C for 2 hours, followed by cooling at room temperature for 2 hours. The substrate material of the flexible printed circuit board 5 is polyimide, and the circuitry is distributed on the flexible substrate.

[0054] The type and magnitude of the force experienced by the sensor are determined by comparing the output results and output characteristics of each TMR.

[0055] In one embodiment, the multidimensional force-tactile sensing electronic skin includes a PDMS protective layer 1, neodymium magnet powder-PDMS magnetic blocks, a silicone rubber substrate 3, TMR magnetic sensing elements, and a flexible PCB. Sixteen TMR elements 4 are arranged in a 4×4 array on the flexible PCB at the bottom layer; the silicone rubber substrate 3 is Ecoflex 00-30 silicone rubber. Sixteen rectangular neodymium magnet powder-PDMS magnetic blocks are embedded in the PDMS protective layer at the top layer. The rectangular magnets are a mixture of neodymium iron boron particles and polydimethylsiloxane. When an external force is applied to the protective layer, the PDMS protective layer deforms, causing the magnetic blocks within the PDMS protective layer to displace. The TMR elements 4, fixed to the FPCB, can sense the magnetic field changes caused by the displacement of the magnetic blocks and convert these magnetic field changes into electrical signals. Experimental calibration is used to establish the correspondence between displacement and magnetic field changes. The output electrical signals are uploaded to a host computer via a multi-channel dynamic acquisition system. The host computer further classifies and processes the signals to determine the magnitude, location, direction, and type of contact force. The method for determining the type, magnitude, and direction of force is as follows: When the sensor is subjected to pressure at a single point, the sensor at the corresponding pixel outputs a corresponding voltage signal, while other signals are almost not output. This enables the location and identification of the contact point.

[0056] When the entire plane of the sensor is subjected to pressure, the sensor is at the position of maximum magnetic field gradient, enabling it to output a higher voltage change. The direction of the voltage change is related to the direction of the magnet. When the N pole is close to the element, the output voltage of a single TMR element 4 decreases; when the S pole is close to the element, the output voltage of a single TMR element 4 increases. Figure 2 As shown. When the entire plane of the sensor is subjected to a tangential force along the positive Y-axis, Increase Decrease and The absolute values ​​of the changes are approximately equal, but The change should be less than The change in quantity. This is due to Only the N-pole magnet is far away from the top of the component, while Not only is the S pole magnet moving away, but the N pole is also moving closer, so The change is larger. Because Only the N-pole magnet is far away from the top of the component. Since only the S-pole magnet is far away from the top of the component, the two change in opposite directions, but their voltage changes are similar.

[0057] When the entire plane of the sensor is subjected to a tangential force along the negative Y-axis, Increase Decrease and The absolute values ​​of the changes are approximately equal, but The change must be smaller than The change. This is due to... Only the S-pole magnet is far away from the top of the component, while Not only is the N pole moving away, but the S pole is also moving closer, so The change is larger. Because Only the S-pole magnet is far away from the top of the component. Only the N-pole magnet is away from the element, so the two change in opposite directions and their voltage changes are similar. When the entire plane of the sensor is subjected to a tangential force along the positive X-axis, Increase Decrease and The absolute values ​​of the changes are approximately equal, but The change should be less than The change in quantity. This is due to Only the S-pole magnet is far away from the top of the component, while Not only is the N pole moving away, but the S pole is also moving closer, so The change is larger. Because Only the S-pole magnet is far away from the top of the component. Only the N-pole magnet is away from the element, so the two change in opposite directions, resulting in similar voltage changes. When the entire plane of the sensor is subjected to a tangential force along the negative X-axis, Decrease Increase and The absolute values ​​of the changes are approximately equal, but The change must be greater than The change in quantity. This is due to Only the N-pole magnet is far away from the top of the component, while Not only is the S pole magnet moving away, but the N pole is also moving closer, so The change is larger. Because Only the N-pole magnet is far away from the top of the component. Only the S-pole magnet is away from the element, so the two change in opposite directions, resulting in similar voltage changes. When the entire plane of the sensor is subjected to a counterclockwise torque along the Z-axis... Increase Decrease and The absolute values ​​of the changes are approximately equal, but The change should be less than The change in quantity. This is due to The farther the component is from the deflection center, the greater the displacement. The change is larger. When the entire plane of the sensor is subjected to a clockwise torque along the Z-axis, Decrease Increase and The absolute values ​​of the changes are approximately equal, but The change should be less than The change in quantity. This is due to The farther the element is from the deflection center, the greater the displacement. The amount of change is greater.

[0058] Although embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the specific embodiments and application fields described above. The specific embodiments described above are merely illustrative and instructive, and not restrictive. Those skilled in the art can make many other forms based on the guidance of this specification and without departing from the scope of protection of the claims of the present invention, and all of these are within the scope of protection of the present invention.

Claims

1. A method for preparing a multidimensional force-tactile sensing electronic skin, characterized in that, It includes the following steps: Multiple TMR components are arrayed on a flexible printed circuit board; A silicone rubber substrate is bonded to a flexible printed circuit board containing an array of multiple TMR elements; A neodymium iron boron-PDMS magnet block was prepared, wherein the neodymium iron boron-PDMS magnet block was composed of neodymium iron boron magnetic particles and polydimethylsiloxane; To prepare the PDMS protective layer, the PDMS main agent and curing agent were mixed and stirred at a ratio of 5:1, and then poured into a mold for the protective layer after being vibrated in an ultrasonic oscillator. The mixture was then placed in a vacuum chamber for vacuum treatment, followed by ultrasonic vibration, and finally placed in a curing chamber for curing and cooling to obtain the PDMS protective layer. The PDMS protective layer and the NdFeB-PDMS magnet block are bonded together using PDMS prepolymer and then stacked on the silicone rubber substrate, so that the NdFeB-PDMS magnet block is located between the silicone rubber substrate and the PDMS protective layer.

2. The method for preparing a multidimensional force-tactile sensing electronic skin according to claim 1, characterized in that, Preferably, in the preparation of NdFeB-PDMS magnet blocks, NdFeB magnetic particles and PDMS prepolymer are mixed in a 2:1 ratio and stirred in an ultrasonic mixer for 30-60 minutes to obtain NdFeB-PDMS prepolymer; a layer of PDMS release agent is sprayed into the magnetic block mold, and then the NdFeB-PDMS prepolymer is poured into the magnetic block mold. The magnetic block mold is placed in a constant magnetic field space device composed of two permanent magnets, and then the entire device is placed in a high-temperature curing oven for curing and cooling. Finally, magnetization is performed along the thickness direction under the magnetic field space.

3. The method for preparing a multidimensional force-tactile sensing electronic skin according to claim 2, characterized in that, The magnetic block mold is placed in a space device with a constant magnetic field of 200mT composed of two permanent magnets. Then the entire device is placed in a high-temperature curing chamber and cured at 80°C for 2 hours. After that, it is cooled at room temperature for 2 hours. Finally, it is magnetized along the thickness direction in a magnetic field space of 5T.

4. The method for preparing a multidimensional force-tactile sensing electronic skin according to claim 1, characterized in that, Mix the PDMS base agent and curing agent at a ratio of 5:1, then stir with a glass rod for 10 minutes. Next, place it in an ultrasonic oscillator and vibrate for 2 minutes. Then pour the PDMS into the upper protective layer mold, and then place the whole thing in a vacuum chamber for vacuum treatment at -0.09MPa for 2 minutes. After that, perform ultrasonic vibration for 5 minutes, and finally place it in a high-temperature curing chamber and cure at 80°C for 2 hours. Finally, cool it at room temperature for 2 hours.

5. The method for preparing a multidimensional force-tactile sensing electronic skin according to claim 1, characterized in that, The PDMS prepolymer is obtained by mixing PDMS main agent and curing agent in a ratio of 8:1 and stirring in an ultrasonic mixer.

6. A multidimensional force-tactile sensing electronic skin, characterized in that, The preparation method of a multidimensional force-tactile sensing electronic skin according to any one of claims 1-5.

7. The multidimensional force-tactile sensing electronic skin according to claim 6, characterized in that, Sixteen TMR components are distributed in a 4×4 array on a flexible printed circuit board.

8. The multidimensional force-tactile sensing electronic skin according to claim 6, characterized in that, The NdFeB-PDMS magnet block has dimensions of 3mm×2.5mm×2mm, the silicone rubber substrate has a thickness of 4mm-5mm, and the TMR element has a Z-axis magnetic sensitivity direction with dimensions of 2.95mm×1.65mm×1.45mm.

9. The multidimensional force-tactile sensing electronic skin according to claim 6, characterized in that, The particle size of neodymium iron boron magnetic particles is 1–2 μm.

10. The multidimensional force-tactile sensing electronic skin according to claim 6, characterized in that, The NdFeB-PDMS magnet blocks are arranged with alternating N and S phases.

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