A tactile sensing array and method of making the same

Abstract

The application discloses a kind of tactile sensor arrays, it is related to sensor technical field, including soft and hard coupling packaging layer, electrode layer is attached and arranged on the soft and hard coupling packaging layer, multistage segmented dot matrix support layer is arranged between the soft and hard coupling packaging layer by adhesion, porous ionic medium layer is clamped and arranged between the electrode layer or between the electrode layer and the soft and hard coupling packaging layer, multilayer array is cooperatively arranged.The application also discloses a kind of tactile sensor array preparation method, steps are as follows: preparation porous ionic medium layer, preparation soft and hard coupling packaging layer, preparation electrode layer, preparation multistage segmented dot matrix support layer, assemble sensor array.The application is compact in structure, cooperatively close, can have excellent strain insensitive and crosstalk suppression performance, and tactile unit response has higher linearity.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, and in particular to a tactile sensing array and its fabrication method. Background Technology

[0002] The physical contact between the human body and the environment contains rich tactile interaction information, which helps humans perceive the characteristics of objects in the surrounding world (such as shape and material) and achieve fine motion control. To mimic the tactile perception capabilities of living organisms, researchers have developed various tactile sensors in recent years to provide robots with perceptual functions similar to human touch. Tactile sensors are sensing elements that can convert physical interaction information (such as pressure, vertical deformation, etc.) into electronic signals that are easily processed by machines, often implemented through transduction principles such as resistance and capacitance. These sensors have become key devices in fields such as robotics, human-computer interaction, and intelligent systems. Among them, ion-capacitive tactile sensors based on the electric double-layer capacitance effect (EDL) have attracted widespread attention due to their high sensitivity and high signal-to-noise ratio. Their working principle is based on the nanoscale ion-electron double-layer interface formed between the electrode and the contact ion dielectric layer, which significantly increases the initial value of the capacitance. Under different pressure conditions, the contact area or distance between the electrode and the ion dielectric changes, causing a change in capacitance and achieving a sensitive response to pressure.

[0003] Tactile sensors are commonly used in flexible structures such as robotic skin or artificial hands, whose surfaces undergo significant bending, stretching, or deformation during movement or interaction with the external environment. However, existing tactile sensor arrays typically lack the ability to adapt to these additional strains, generating a wide range of false response signals under bending or stretching conditions. For example, even without actual touch pressure, the sensor array may trigger erroneous signals due to surface deformation, greatly limiting its reliability and applicability in real-world applications.

[0004] Furthermore, when such sensors are fabricated into compact, high-density tactile sensor arrays, signal crosstalk may occur between adjacent units because multiple sensing units share the same ionic medium. Specifically, when a unit is subjected to pressure, deformation conduction / leakage current can induce signal responses in adjacent, untouched units, leading to erroneous perception results. This crosstalk phenomenon significantly weakens the signal resolution and sensing accuracy of the sensor array, severely impacting the accurate acquisition of tactile information. Summary of the Invention

[0005] In view of the above-mentioned deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a strain-insensitive, crosstalk-free tactile sensor array and its fabrication method.

[0006] To achieve the above objectives, the present invention provides a tactile sensor array that solves the aforementioned technical problems. The array includes a flexible-rigid coupling encapsulation layer, an electrode layer attached to the flexible-rigid coupling encapsulation layer, a multi-level segmented lattice support layer bonded between the flexible-rigid coupling encapsulation layers, and a porous ion-dielectric layer sandwiched between the electrode layers or between the electrode layers and the flexible-rigid coupling encapsulation layer. Through the coordinated arrangement of the multi-layer array, the tactile sensor array achieves insensitivity to strain and suppression of crosstalk.

[0007] Furthermore, the rigid-flexible coupling encapsulation layer includes an array of high-modulus rigid regions covered by a low-modulus soft material, and a flexible connection region formed by filling the pores between the high-modulus rigid regions with a low-modulus soft material. The material used for the high-modulus rigid regions is a high-modulus hard material, such as PDMS, TPU, or PVA. The low-modulus soft material is PDMS, Ecoflex series, or TPU. The thickness of the rigid-flexible coupling encapsulation layer is 100-300 micrometers.

[0008] Furthermore, the electrode layer is configured as an electrode unit array, and the electrode layer adopts a parallel electrode structure or a coplanar electrode structure. The parallel electrodes are row electrodes or column electrodes, and the coplanar electrode structure is an interdigitated electrode, a spiral interdigitated electrode, or a rectangular electrode.

[0009] Furthermore, the multi-level segmented lattice support layer is a relatively rigid support unit, which is disposed between the layers of the flexible connection area. The multi-level segmented lattice support unit adopts a cylindrical, square, or conical lattice structure, with the size of a single lattice structure ranging from 100 to 300 micrometers and the spacing ranging from 100 to 300 micrometers. The material used for the multi-level segmented lattice support layer is PDMS, TPU, or PVA.

[0010] Furthermore, the porous ion medium layer is an array unit, sandwiched between the electrode unit array layers or between the high modulus hard region array layer and the electrode unit array layer. The material used for the porous ion medium layer is an ion gel composed of PVD (F-HFP) and ionic liquid [EMIM][TFSI] mixed in a 1:1 ratio and attached to a high porosity 3D mesh framework. The high porosity 3D mesh framework is melamine open-cell foam or open-cell sponge or open-cell foam prepared from PDMS / Ecoflex material.

[0011] Furthermore, the tactile sensor array of the present invention adopts a 5-layer structure, which is arranged from top to bottom as follows: first layer: soft and hard coupling encapsulation layer; second layer: row electrode layer; third layer: porous ion dielectric layer array unit and multi-level segmented lattice support unit located between the porous ion dielectric layer array units; fourth layer: column electrode layer; fifth layer: soft and hard coupling encapsulation layer. The electrode unit array of the row and column electrode layers is disposed on the high modulus hard region array of the first layer and the fifth layer. The array unit of the porous ion dielectric layer is directly contacted between the electrode array layers of the second layer and the fourth layer.

[0012] Furthermore, the tactile sensor array of the present invention adopts a four-layer structure, which is arranged from top to bottom as follows: first layer: soft and hard coupling encapsulation layer; second layer: porous ion dielectric layer array unit and multi-level segmented lattice support unit located between the porous ion dielectric layer array units; third layer: coplanar electrode layer; fourth layer: soft and hard coupling encapsulation layer. The electrode unit array of the coplanar electrode layer is disposed on the high modulus hard region array of the fourth layer, and the array unit of the porous ion dielectric layer is directly contacted between the high modulus hard region array layer of the first layer and the electrode array layer of the third layer.

[0013] The present invention also provides a method for preparing the above-mentioned tactile sensing array, comprising the following steps:

[0014] Step 1: Prepare a porous ion-dielectric layer;

[0015] Step 2: Prepare the flexible and rigid coupling encapsulation layer;

[0016] Step 3: Prepare the electrode layer;

[0017] Step 4: Prepare a multi-level segmented lattice support layer;

[0018] Step 5: Assemble the sensor array.

[0019] further,

[0020] Step one also includes the following steps:

[0021] Step 1.1 Dissolve the ionogel in an organic solvent to prepare ionogel solutions of different concentrations;

[0022] Step 1.2 The ion gel solution obtained in the above steps is attached to the high porosity 3D mesh framework by coating or embedding.

[0023] Step 1.3: Completely dry the 3D mesh framework saturated with ionogel solution;

[0024] Step 1.4 Use a die cutter to cut the dried porous ion medium into array units that match the sensing electrodes.

[0025] Step two also includes the following steps:

[0026] Step 2.1 Prepare arrays of high-modulus hard regions using high-modulus material through molding or dispensing printing;

[0027] Step 2.2 uses an extrusion or scraping process to press the low-modulus material into the gaps between the high-modulus hard regions, while simultaneously covering the high-modulus hard regions.

[0028] Step three also includes the following steps:

[0029] Step 3.1 On the soft-hard coupling encapsulation layer, align the high-modulus hard regions by printing or dispensing to fabricate an array of electrodes;

[0030] Step 3.2 involves drying.

[0031] Step four is described in detail below:

[0032] High-modulus materials are processed through a multi-level segmented lattice support structure mold, and then formed into a multi-level segmented lattice support layer through dispensing printing or mold making processes.

[0033] Step five also includes the following steps:

[0034] Step 5.1 Cover the back of the multi-level segmented lattice support layer with adhesive;

[0035] Step 5.2 For parallel electrode configurations, use a die cutter to cut away the electrode corresponding areas of the multi-level segmented lattice support layer, and then bond it to the soft and hard coupling encapsulation layer of the printed electrode layer; for coplanar electrode configurations, bond it to the soft and hard coupling encapsulation layer on the side without printed electrodes.

[0036] Step 5.3 After bonding the multi-level segmented lattice support layer with the soft and hard coupling encapsulation layer, demold and remove it. Bond the multi-level segmented lattice support layer with another soft and hard coupling encapsulation layer, and clamp the array-divided porous ion medium between the electrode array layers or between the high modulus hard region array layer and the electrode array layer.

[0037] further,

[0038] In step 1.1, the mass ratio of the ion gel to the organic solvent is 1:16, 1:12, or 1:8, and the organic solvent is acetone.

[0039] The coating / embedding method described in step 1.2 is dip coating or spray coating;

[0040] In step 1.3, when melamine open-cell foam is used as a 3D mesh framework, the drying temperature of the ion gel solution is 60°C.

[0041] Compared with the prior art, the present invention has the following advantages:

[0042] (1) With minimal impact on spatial resolution, it is possible to achieve insensitivity to maximum 75% tensile deformation and insensitivity to bending with a radius >10mm.

[0043] (2) For mechanical crosstalk, it can reduce the vertical deformation of adjacent units by 89.8% and achieve a crosstalk suppression ratio of about 30dB.

[0044] (3) The prepared ion tactile sensor can have good response linearity over a large pressure range.

[0045] The following will further explain the concept, specific structure, and technical effects of the present invention in conjunction with the accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of a preferred embodiment of the present invention;

[0047] Figure 2 This is a schematic diagram of another preferred embodiment of the present invention;

[0048] Figure 3 This is a schematic diagram of the preparation method of the present invention;

[0049] Figure 4 The high-modulus hard unit and the soft-hard coupled encapsulation-electrode composite layer prepared for this invention;

[0050] Figure 5 The microstructure of the porous ion medium prepared in this invention;

[0051] Figure 6 The morphology of the multi-level segmented lattice support prepared for this invention and its variation with bending;

[0052] Figure 7 These are images from actual machine tests of the tensile deformation of the soft-hard coupled encapsulation-electrode composite layer of the present invention.

[0053] Figure 8 Simulated deformation and internal stress of the soft-hard coupled encapsulation-electrode composite layer of the present invention;

[0054] Figure 9 Tactile array photographs prepared for this invention;

[0055] Figure 10 The response performance of the tactile sensor array with different concentrations of ion gel ratios prepared in this invention;

[0056] Figure 11 The differences in initial values ​​and response of the tactile sensor prepared in this invention under different tensile strains;

[0057] Figure 12 The false response of the tactile sensor prepared in this invention under different bending radii;

[0058] Figure 13 This paper compares the crosstalk of the tactile sensor array before and after adding a multi-level segmented dot matrix support structure, as prepared in this invention.

[0059] Wherein: 0-tactile sensor array, 1-soft and hard coupling encapsulation layer, 100-high modulus hard region, 101-soft connection region, 2-row and column electrode layer, 3-multi-level segmented lattice support layer, 4-porous ion medium layer, 6-coplanar electrode layer, 601-spiral interdigital electrode, 7-soft and hard coupling encapsulation electrode composite layer. Detailed Implementation

[0060] The preferred embodiments of the present invention are described below with reference to the accompanying drawings to make the technical content clearer and easier to understand. The present invention can be embodied in many different forms, and the scope of protection of the present invention is not limited to the embodiments mentioned herein.

[0061] In the accompanying drawings, components with the same structure are indicated by the same numerical designation, and components with similar structures or functions are indicated by similar numerical designations. The dimensions and thicknesses of each component shown in the drawings are arbitrary, and the present invention does not limit the dimensions and thicknesses of each component. To make the illustrations clearer, the thickness of some components has been appropriately exaggerated in the drawings.

[0062] like Figure 1-2 As shown, the tactile sensing array of this invention adopts a multi-layer structure collaborative design, including a rigid-soft coupling encapsulation layer 1, an electrode layer, a multi-level segmented lattice support layer 3, and a porous ion dielectric layer 4. The rigid-soft coupling encapsulation layer 1 includes a high-modulus rigid region array 100 and a flexible connection region 101. The high-modulus rigid region 100 is made of high-modulus hard materials such as PDMS, TPU, and PVA, while the low-modulus flexible connection region 101 and the encapsulation are made of low-modulus soft materials such as PDMS, Ecoflex series, and TPU. The low-modulus soft material covers the high-modulus rigid region array 100 and fills the gaps between the high-modulus rigid region arrays to form the flexible connection region 101. The thickness of the rigid-soft coupling encapsulation layer 1 is 100-300 micrometers. The rigid-soft coupling encapsulation layer 1 not only concentrates tensile strain in the flexible connection region 101 of adjacent units, but also ensures that the sensing unit is not affected by tensile or other lateral strains.

[0063] The electrode layer is an array of electrode units. The electrode layer design can adopt a parallel electrode structure (i.e., row and column electrodes) or a coplanar electrode structure. The row and column electrodes are row electrodes or column electrodes, and the coplanar electrodes are interdigitated electrodes, spiral interdigitated electrodes, rectangular electrodes, etc. The electrode layer is attached to the high-modulus hard region 100 array surface of the soft and hard coupling encapsulation layer 1. The electrode layer and the soft and hard coupling encapsulation layer can be integrally composited to form a soft and hard coupling encapsulation electrode composite layer 7.

[0064] The porous ion-dielectric layer 4 is an ion-dielectric unit / region array. The material used is an ion gel composed of PVD (F-HFP) and ionic liquids [EMIM][TFSI] mixed in a 1:1 ratio and attached to a high-porosity 3D mesh framework. However, it is not limited to PVD (F-HFP) and ionic liquids [EMIM][TFSI]. The high-porosity 3D mesh framework can be melamine open-cell foam, open-cell sponge, or open-cell foam prepared from materials such as PDMS / Ecoflex. The porous ion-dielectric layer 4 is sandwiched between electrode unit array layers or between a high-modulus rigid region array layer and an electrode unit array layer. Using high-porosity organic foam as the ion gel embedding framework not only allows for the construction of a 3D distribution of the ion gel, resulting in a greater contact area change efficiency, but also, due to its extremely high porosity, the Poisson's ratio of the overall material is close to 0, and its compressive modulus hardly changes with the compression process. This makes the material's compression amount and the applied pressure value exhibit an approximately linear relationship. The effective contact area between the porous ion medium layer 4 and the electrode layer is also approximately proportional to the compression amount, ultimately exhibiting a linear response characteristic of relative capacitance change with pressure.

[0065] The multi-level segmented lattice support layer 3 has high modulus characteristics and is relatively rigid. The materials used include PDMS, TPU, and PVA. The multi-level segmented lattice support layer 3 employs cylindrical, square, and conical lattice structures distributed in multiple rows and columns between adjacent independent unit ion-dielectric regions. The size of a single lattice structure ranges from 100 to 300 micrometers, and the spacing is also from 100 to 300 micrometers. The multi-level segmented lattice support layer 3 is bonded to the flexible connection area 101 of the top layer and the bottom layer of the soft-hard coupling encapsulation layer 1 using adhesive. This provides vertical support and isolation, resisting vertical strain caused by bending / Poisson effect of the tactile sensor array without affecting tensile strength, thus preventing false activation of the sensing unit. The multi-level lattice support layer 3 forms vertically supporting isolation bands between adjacent porous ion dielectric units, resisting vertical deformation. Together with the soft-hard coupling encapsulation layer 1 (which reduces stress transmission between units), it significantly reduces mechanical crosstalk between adjacent units caused by deformation / stress transmission. Furthermore, the multi-level segmented lattice support layer 3 isolates the porous ion dielectric layer 4, enabling each unit's ion dielectric layer to be independent, thus reducing electrical crosstalk between units caused by ion movement.

[0066] Example 1

[0067] like Figure 1 As shown, a preferred embodiment of the tactile sensing array of the present invention includes a soft and hard coupling encapsulation layer 1, a row and column electrode layer 2 (adopting a parallel electrode structure), an independent porous ion medium layer 4 for each unit, and a multi-level segmented lattice support layer 3 located between each unit, wherein the row and column electrode layer 2 is a row electrode layer or a column electrode layer.

[0068] The tactile sensor array adopts a 5-layer structure design, from top to bottom: the first layer, the second layer, the third layer, the fourth layer, and the fifth layer. The first layer (i.e., the top layer) is the soft and hard coupling encapsulation layer 1, the second layer is the row electrode layer, the third layer is the porous ion dielectric layer array unit and the multi-level segmented dot matrix support unit located between the porous ion dielectric layer array units, the fourth layer is the column electrode layer, and the fifth layer (i.e., the bottom layer) is the soft and hard coupling encapsulation layer 1.

[0069] In the tactile sensor array, the sensing electrode unit regions of the row electrode layer (second layer) correspond to the high-modulus hard region 100 of the flexible-rigid coupling encapsulation layer 1 (first layer), and the sensing electrode unit regions of the column electrode layer (fourth layer) correspond to the high-modulus hard region 100 of the flexible-rigid coupling encapsulation layer 1 (fifth layer). This structure gives the sensing electrode regions high-modulus characteristics, making them less prone to stretching, while the flexible connection regions between adjacent units have low-modulus characteristics, making them easier to stretch. When the tactile sensor array is stretched, the stretching deformation is mainly concentrated in the low-modulus flexible connection regions 101, preventing the sensing electrode regions from being deformed due to stretching. Moreover, under the same overall stretching deformation, the stress generated inside the flexible-rigid coupling encapsulation layer 1 is smaller due to the presence of the low-modulus flexible connection regions 101. The independent porous ion-dielectric regions of each unit directly contact the surfaces of the upper and lower electrode layers (i.e., the second and fourth layers), while the multi-level segmented lattice support layer 3 is distributed between the independent porous ion-dielectric regions of each unit, corresponding to the flexible connection regions 101 of the flexible-rigid coupling encapsulation layer 1.

[0070] Example 2

[0071] like Figure 2 As shown, in another preferred embodiment of the present invention, the electrode adopts a coplanar electrode structure, which differs from that in Embodiment 1. The tactile sensor adopts a 4-layer structure design, which consists of a first layer, a second layer, a third layer and a fourth layer from top to bottom. The first layer (i.e., the top layer) is a soft and hard coupling encapsulation layer 1, the second layer is a porous ion dielectric layer array unit and a multi-level segmented lattice support unit located between the porous ion dielectric layer array units, the third layer is a coplanar electrode layer 6, and the fourth layer (i.e., the bottom layer) is a soft and hard coupling encapsulation layer 1.

[0072] In the tactile sensor array, the sensing electrode unit region of the coplanar electrode layer 6 (third layer) corresponds to the high-modulus hard region 100 of the flexible-rigid coupling encapsulation layer 1 (fourth layer). When the tactile sensor array is stretched, the deformation is mainly concentrated in the low-modulus flexible connection region 101, while the sensing electrode unit region (i.e., the high-modulus hard region 100) is almost unaffected. Moreover, under the same overall tensile deformation, the stress generated inside the flexible-rigid coupling encapsulation layer 1 is smaller due to the presence of the low-modulus flexible connection region 101. The independent ion-dielectric region of each unit directly contacts the coplanar electrode surface 6 (third layer) and the high-modulus hard region 100 of the flexible-rigid coupling encapsulation layer 1 (first layer). The multi-level segmented lattice support layer 3 is distributed between the independent ion-dielectric regions of each unit, corresponding to the flexible connection region 101 of the flexible-rigid coupling encapsulation layer 1 (first and fourth layers).

[0073] like Figure 3 As shown, the present invention also provides a method for preparing the above-mentioned tactile sensing array, the specific steps of which are as follows:

[0074] Step 1: Preparation of a porous ion-dielectric layer

[0075] First, ionogel solutions of different concentrations were prepared by dissolving the ionogel in an organic solvent. The mass ratio of ionogel to organic solvent was 1:16, 1:12, and 1:8, and the organic solvent was acetone, etc.

[0076] Next, the ionogel solution obtained in the above steps is attached to a high-porosity 3D mesh framework via a coating / embedding method. The coating / embedding method can be dip coating or spray coating, etc.

[0077] The 3D mesh framework, saturated with ionogel solution, is then completely dried. Finally, it is cut into array units the size of sensing electrodes using a die-cutting tool. Melamine open-cell foam, after being used as the 3D mesh framework with the ionogel solution attached, can be completely dried at 60°C.

[0078] Step 2: Fabrication of the soft-hard coupling encapsulation layer

[0079] First, a high-modulus hard region 100 is prepared by using a mold with an array of openings to prepare the high-modulus material through molding or dispensing printing. Then, a low-modulus material is pressed into the gaps between the high-modulus hard regions 100 by extrusion or scraping processes, and covers the high-modulus hard regions 100 to form a low-modulus soft connection region 101, and the whole is formed into an integrated film with soft and hard coupling.

[0080] Step 3: Prepare the electrode layer

[0081] On the hard-soft coupling encapsulation layer 1, the high-modulus hard region 100 is aligned by printing or dispensing to prepare an array of electrodes, and then the hard-soft coupling encapsulation electrode composite layer 7 is formed by drying.

[0082] Step 4: Prepare a multi-level segmented lattice support layer

[0083] High-modulus materials are processed through multi-level segmented lattice support structure molds, and then formed into multi-row and column distributed lattice structure support layers such as cylindrical, square, and conical shapes using processes such as adhesive printing or mold making.

[0084] Step 5: Assemble the sensor array

[0085] First, adhesive is applied to the back of the multi-level segmented lattice support layer 3. For parallel electrodes, the corresponding electrode area of ​​the multi-level segmented lattice support layer 3 is cut away using a die-cutting tool to expose the electrode. Then, it is bonded to the flexible and rigid coupling encapsulation layer 1 with the printed electrode layer. For coplanar electrodes, no cutting is required; they only need to be bonded to the flexible and rigid coupling encapsulation layer 1 on the side without the printed electrode layer.

[0086] Then, the multi-level segmented lattice support layer 3 is bonded to the soft and hard coupling encapsulation layer 1 and demolded. The multi-level segmented lattice support layer is bonded to another soft and hard coupling encapsulation layer 1, and the array-divided porous ion medium layer is sandwiched between the electrode array layers or between the high modulus hard region 100 array layer and the electrode array layer to form a tactile sensing array.

[0087] like Figure 4 As shown, the left figure is the high modulus hard region 100 prepared by the above preparation method, and the right figure is the soft and hard coupling encapsulation electrode composite layer 7 prepared by the above method, which is the composite layer formed after the electrode regions of the row and column electrode layers are aligned and combined with the high modulus hard region 100 of the soft and hard coupling encapsulation layer 1.

[0088] like Figure 5 The image shows the microstructure of the porous ionic medium prepared using the above method. Figure 4 The 3D mesh embedding patterns with different ion gel concentrations can be observed.

[0089] like Figure 6 The image shows the morphology of the multi-level segmented lattice support layer 3 prepared using the above-described method. Figure 5 The multi-level segmented lattice support structure is distributed in the connection area between different unit electrodes (i.e., the flexible connection area 101 of the soft-hard coupling encapsulation layer 1). From Figure 5 It can be seen that this multi-level segmented dot matrix support structure can unfold according to the change of the bending radius of the tactile sensor array, continuously forming effective support.

[0090] like Figure 7The figure shows the tensile deformation test results of the soft-hard coupling encapsulated electrode composite layer 7 prepared by the above preparation method. It can be seen from the figure that under a total tensile strain of 50%, the main tensile deformation is mainly generated by the low modulus soft connection region 101 between adjacent electrodes, while the electrode region (that is, the corresponding high modulus hard region 100) is less affected by tensile deformation.

[0091] like Figure 8 The figures show simulation results for the soft-hard coupled encapsulated electrode composite layer 7 and the homogeneous PDMS substrate, reflecting the changes in their internal states. The upper figure shows the area change rate of the array electrodes under a total stretch of 50%, indicating that the area change of the soft-hard coupled encapsulated electrode composite layer 7 is reduced by 79% compared to the homogeneous PDMS substrate. The lower figure shows the stress distribution within the two encapsulation layers, showing that the stress inside the soft-hard coupled encapsulated electrode composite layer 7 is significantly reduced compared to the homogeneous PDMS substrate, with an average stress reduction of 90%.

[0092] like Figure 9 The image shown is a photograph of the tactile sensor array 0 of Embodiment 1 of the present invention, prepared using the above-described method.

[0093] like Figure 10 The figure shows the tactile sensing array response performance using different ion gel ratios as porous ion medium layer 4. It can be seen from the figure that the highest sensitivity (average 2.733 kPa) is achieved when the ion gel solution concentration is 1:8. -1 It exhibits good linearity (0.986) over a wide detection range (0-1400 kPa).

[0094] like Figure 11 The figure shows the differences in initial capacitance and response to pressure of the tactile sensor array fabricated using the above method under different overall stretch rates. It can be seen from the figure that even at a maximum stretch rate of 75%, the response remains relatively consistent, with a statistically obtained response deviation within ±10.47%. Furthermore, the initial capacitance of the tactile unit changes even less with the stretch rate, with a relative change of <7% at 75% stretch rate, less than the response amplitude generated by 1 Pa (calculated from the average sensitivity). Therefore, the use of the soft-hard coupling encapsulation layer 1 significantly improves the insensitivity of the tactile sensor array to tensile deformation.

[0095] like Figure 12The figure shows the false response of the tactile sensor array fabricated using the above method under different bending radii. As can be seen from the figure, for bending radii > 10 mm, the statistically obtained average false response is approximately < 0.17, roughly the response value generated by a 0.06 kPa pressure (calculated from the average sensitivity). Therefore, the use of the soft-hard coupling encapsulation layer 1 significantly improves the insensitivity of the tactile sensor array to bending deformation.

[0096] like Figure 13 As shown, the figure compares the crosstalk suppression results of the tactile sensor array with and without the same soft-hard coupling encapsulated electrode composite layer 7 and porous ion dielectric layer 4. It can be seen from the figure that the multi-level segmented lattice support structure significantly reduces the crosstalk influence of the centrally loaded unit (O) on adjacent units (ABCD), and there is almost no visible crosstalk signal between diagonally adjacent units. Here, the degree of influence of the signal of the centrally loaded unit on the signal of adjacent units is statistically and quantitatively calculated, using the crosstalk suppression ratio defined as follows:

[0097] I CRR =-20log 10 (ΔC stressed / ΔC adiacent )

[0098] Where ΔCstressed represents the capacitive signal response generated by the central pressure-bearing unit, and ΔCadjacent represents the capacitive signal response generated by the vertically adjacent unit. The crosstalk suppression ratio of a tactile sensing array without a multi-level segmented dot matrix support structure is approximately 15dB, while that of a tactile sensing array using a multi-level dot matrix support structure reaches 30dB. Therefore, employing a multi-level dot matrix support structure significantly improves the crosstalk suppression capability of the tactile sensing array.

[0099] This invention features a compact and tightly integrated tactile sensor array. With minimal impact on spatial resolution, it achieves excellent strain insensitivity and crosstalk suppression. The tactile units exhibit high linearity and are insensitive to tensile deformation up to 75% (initial drift <7%, pressure response difference ±10.47%) and bending with a radius >10mm (the curvature of the human hand's finger surface is approximately 10mm; at a 10mm bending radius, the relative capacitance change is <0.17, corresponding to a response of approximately 0.06kPa). Regarding mechanical crosstalk (vertical deformation transmission), it reduces the vertical deformation experienced by adjacent units by 89.8%, achieving a crosstalk suppression ratio of approximately 30dB (i.e., the influence of the contact unit on adjacent units is approximately 1 / 30). It maintains effective responsiveness over a wide pressure range (0-1400kPa) with good response linearity (0.986). It readily and robustly captures tactile information accurately on soft, curved human-machine surfaces, achieving precise response to contact information.

[0100] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A tactile sensing array, characterized by, The soft and hard coupling packaging layer, the electrode layer attached and arranged on the soft and hard coupling packaging layer, the multi-stage segmented dot matrix support layer arranged between the soft and hard coupling packaging layers by adhesion, and the porous ion medium layer clamped between the electrode layers or between the electrode layers and the soft and hard coupling packaging layers are included. The soft and hard coupling packaging layer includes an array of high modulus hard area coated with low modulus soft material, and a soft connection area formed by filling the pores between the array of high modulus hard area with low modulus soft material. The multi-stage segmented dot matrix support layer is arranged between the soft connection area layers. Through the coordinated arrangement of the multi-layer array, the strain insensitivity of the tactile sensor array and the suppression of crosstalk are realized.

2. The tactile sensor array of claim 1, wherein, The high modulus hard material used in the high modulus hard area is PDMS or TPU or PVA, and the low modulus soft material is PDMS or Ecoflex series or TPU, and the thickness of the soft and hard coupling packaging layer is 100-300 microns.

3. The tactile sensor array of claim 2, wherein, The electrode layer is an array of electrode units arranged in parallel or coplanar electrode structure, and the parallel electrode is a row electrode or a column electrode, and the coplanar electrode structure is an interdigital electrode or a rectangular electrode.

4. The tactile sensor array of claim 3, wherein, The multi-stage segmented dot matrix support layer is a relatively hard support unit, and the multi-stage segmented dot matrix support unit adopts a cylindrical or square column or conical dot matrix structure, and the size of a single dot matrix structure is 100 to 300 microns, and the pitch is 100 to 300 microns, and the material used in the multi-stage segmented dot matrix support layer is PDMS or TPU or PVA.

5. The tactile sensor array of claim 4, wherein, The porous ion medium layer is an array unit clamped between the electrode unit array layer or between the array layer of high modulus hard area and the electrode unit array layer, and the material used in the porous ion medium layer is an ion gel formed by mixing PVD(F-HFP) and ionic liquid [EMIM][TFSI] in a ratio of 1:1 attached to a high porosity 3D grid frame, and the high porosity 3D grid frame is melamine open-cell foam or open-cell sponge or open-cell foam prepared from PDMS / Ecoflex material.

6. The tactile sensor array of claim 5, wherein, A 5-layer structure is adopted, and from top to bottom, it is sequentially arranged as a first layer: a soft and hard coupling packaging layer, a second layer: a row electrode layer, a third layer: a porous ion medium layer array unit and a multi-stage segmented dot matrix support unit located between the porous ion medium layer array units, a fourth layer: a column electrode layer, and a fifth layer: a soft and hard coupling packaging layer, and the electrode unit array of the row and column electrode layers is arranged on the array of high modulus hard area of the first layer and the fifth layer, and the array unit of the porous ion medium layer is directly contacted and arranged between the electrode array layers of the second layer and the fourth layer.

7. The tactile sensor array of claim 5, wherein, Adopt 4 layers structure, from top to bottom is set as first layer: soft and hard coupling packaging layer, second layer: porous ion medium layer array unit and multi-stage segmented dot matrix support unit between porous ion medium layer array unit, third layer: coplanar electrode layer, fourth layer: soft and hard coupling packaging layer, electrode unit array of the coplanar electrode layer is arranged on the high modulus hard area array of the fourth layer, the array unit of the porous ion medium layer is directly contacted and arranged between the high modulus hard area array layer of the first layer and the electrode array layer of the third layer.

8. A method of manufacturing a tactile sensor array as claimed in any one of the claims 1-7, characterized in that, It comprises the following steps: Step one, preparation of porous ion medium layer; Step two, preparation of soft and hard coupling packaging layer; Step three, preparation of electrode layer; Step four, preparation of multi-stage segmented dot matrix support layer; Step five, assembly of sensor array.

9. The method of tactile sensing array of claim 8, wherein, The step one further comprises the following steps: Step 1.1 Dissolve the ion gel into organic solvent to prepare ion gel solution with different concentrations; Step 1.2 Attach the ion gel solution obtained in the above step to the high open porosity 3D grid frame by coating or embedding method; Step 1.3 Dry the 3D grid frame saturated with ion gel solution completely; Step 1.4 Cut the dried porous ion medium into array units matching the sensing electrodes using a die cutter; The step two further comprises the following steps: Step 2.1 Prepare the high modulus hard area of the array by flip molding or dispensing printing of high modulus material; Step 2.2 Use extrusion or doctor blade coating process to press the low modulus material into the gap between the high modulus hard area, while coating the high modulus hard area; The step three further comprises the following steps: Step 3.1 On the soft and hard coupling packaging layer, prepare the array electrode by printing or dispensing printing of high modulus hard area in alignment; Step 3.2 Perform drying treatment; The step four is specifically as follows: Form the multi-stage segmented dot matrix structure support layer by dispensing printing or flip molding process of high modulus material through the multi-stage segmented dot matrix support structure mold; The step five further comprises the following steps: Step 5.1 Cover adhesive on the back of the multi-stage segmented dot matrix support layer; Step 5.2 For parallel electrode configuration, use a die cutter to cut off the electrode corresponding area of the multi-stage segmented dot matrix support layer, and then bond it with the soft and hard coupling packaging layer of the printed electrode layer; for coplanar electrode configuration, bond it with the soft and hard coupling packaging layer of the side without printed electrode; Step 5.3 After bonding the multi-stage segmented dot matrix support layer with the soft and hard coupling packaging layer, demold and take out, bond the multi-stage segmented dot matrix support layer with another piece of soft and hard coupling packaging layer, and clamp the array segmented porous ion medium between the electrode array layer or between the high modulus hard area array layer and the electrode array layer.

10. The method of tactile sensing array of claim 9, wherein, The mass ratio of ion gel to organic solvent in step 1.1 is 1:16, 1:12, 1:8, and the organic solvent is acetone; The coating / embedding method in step 1.2 is dip coating or spraying; The drying temperature of the ion gel solution is 60°C when the melamine open-cell foam in step 1.3 is used as a 3D grid framework.

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