Self-powered metal recognition and touch pressure sensing integrated device, system and sensing method

Abstract

The invention relates to a self-powered metal recognition and touch pressure sensing integrated device, system and sensing method, and belongs to the technical field of flexible electronics and self-powered sensing. The device is provided with a first electrode, a touch sensitive layer, a common electrode, a metal identification layer and a conductive electrode which are sequentially stacked in the thickness direction, and the first electrode, the touch sensitive layer, the common electrode, the metal identification layer and the conductive electrode are in contact and serve as common reference electrodes. The negative terminal is a low-resistance ionic conducting medium and is used for generating a first open-circuit potential difference signal representing the material of a measured object at the negative terminal; the electrode is a high-resistance sensitive layer with a surface microstructure, the microstructure is compacted when the electrode is pressed, so that the effective contact between the electrode and the sensitive layer is enhanced, the equivalent impedance is remarkably reduced, and a second open-circuit potential difference signal changing along with the pressure is generated at a-end. According to the invention, material identification and touch pressure synchronous output without external excitation can be realized, crosstalk is reduced, stability is improved, and the method is suitable for scenes such as robot clamping jaw self-adaptive grabbing and electronic skin and wearable interaction.

Description

A self-powered integrated device, system, and sensing method for metal recognition and tactile pressure sensing. Technical Field

[0001] This invention belongs to the field of flexible electronics and self-powered sensing technology, and relates to a self-powered metal recognition and tactile pressure sensing integrated device, system and sensing method. Background Technology

[0002] In applications such as robotic grasping, human-computer interaction, and electronic skin, end-effector sensing units typically need to acquire at least two types of key information simultaneously: one is the material properties of the contact object (e.g., whether it is metal and its type), used for workpiece sorting, contact object identification, and grasping strategy selection; the other is the mechanical information of the contact process (e.g., pressure magnitude, contact state changes), used for force control closed-loop, slip suppression, and compliant grasping. In existing technologies, material recognition and tactile pressure sensing often rely on different devices and measurement links: tactile pressure sensing often employs piezoresistive, piezoresistive, or impedance variation structures; metal recognition may use electromagnetic induction / eddy current, contact potential difference, or multi-sensor fusion. To achieve multimodal sensing at the same end-effector, engineering typically requires multiple device stacks, multiple electrode arrangements, and multiple acquisition circuits, leading to structural complexity, increased wiring burden, and signal crosstalk.

[0003] In the prior art, the invention patent with publication number CN102749158B discloses "a self-powered pressure sensor," which utilizes the self-powered effect to achieve electrical signal output under pressure triggering, and can complete pressure detection without external excitation. However, such solutions are usually aimed at acquiring single pressure / tactile information, and the structure and output mechanism are mostly built around a single sensing unit. It is difficult to simultaneously realize the identification of the contact object material (especially different metal types) and tactile pressure sensing in the same device, and it does not propose a structural design to reduce the mutual loading and discharge of different modal signals under the condition of shared electrode equivalent load change.

[0004] In the prior art, the invention patent with publication number CN107850497A discloses a "pressure sensing scheme based on the generation of electrical signals through the redistribution of mobile ions in a piezoelectric ion layer," which utilizes the ion redistribution induced by pressure to obtain pressure-related electrical signals. However, this scheme mainly focuses on pressure sensing itself and does not involve the identification of the material of the contact object; at the same time, its electrode-ion layer coupling method mainly serves the output of pressure electrical signals, and does not provide a solution for how to avoid the low-resistance circuit forming a parallel load on the high-resistance tactile signal, leading to signal attenuation and zero-point drift, when the device simultaneously carries a "low-resistance recognition channel + high-resistance tactile channel."

[0005] In the prior art, the invention patent with publication number CN108161994A discloses "a multimodal tactile sensing device", which can acquire multimodal information such as three-dimensional contact force, temperature, and texture to improve the fine manipulation ability of robot hands. However, such multimodal devices usually rely on the integration of multiple sensing modules or the superposition of multiple heterogeneous sensing principles, resulting in complex structures and wiring, multiple measurement links, and strong dependence on external power supply and acquisition circuits. This makes it difficult to meet the engineering constraints of flexible electronic skin, such as "thin and light fit, array expansion, low power consumption, and even self-powered operation". Its multimodal parallel output relies more on system-level fusion and does not propose a targeted impedance layering and mutual interference suppression structure around "parallel output of dual signals with open circuit potential difference (open circuit voltage) under shared reference electrode".

[0006] In the prior art, the invention patent with publication number CN115431289B discloses a "four-in-one multimodal tactile sensor and method," which acquires tactile information such as pressure distribution, hardness, and texture through different modules. However, this solution is essentially still a modular / multi-device integration approach, resulting in high system complexity and engineering implementation costs. Furthermore, it does not involve a self-powered output path based primarily on the open-circuit potential difference at the electrode-ion dielectric interface, nor does it resolve the critical contradiction of simultaneously achieving "object material recognition + tactile pressure" within the same compact stacked structure while ensuring that the two signals do not create a load on each other.

[0007] In the prior art, the invention patent with publication number CN103308597A discloses a "Method and System for Detecting Small Holes in Metal Profiles Based on Eddy Current Sensors," which realizes eddy current detection of metal objects through an eddy current probe and a signal controller (including a signal generation circuit and a signal processing circuit). However, eddy current / electromagnetic metal recognition usually requires an excitation-reception-amplification processing link, and the device form is mostly a combination of probe and controller, which is difficult to integrate with a flexible tactile unit in the same location, and even more difficult to achieve synchronous output with tactile pressure without the need for an external excitation power supply; in addition, this type of solution focuses on defect / geometric detection or electromagnetic feature extraction, which differs from the route of using the intrinsic potential difference of the contact interface to perform fine characterization of different metal material categories.

[0008] Meanwhile, for flexible sensing schemes related to potential-type or ion-conducting media, ion migration and interface state are quite sensitive to environmental humidity, temperature and time drift. Under multi-layer structure or electrode reuse conditions, the changes in contact state and equivalent impedance of different functional layers over time can easily lead to baseline drift and reduced repeatability of open-circuit potential difference (open-circuit voltage) at the reference electrode, thereby further aggravating the stability problem of multi-mode synchronous output.

[0009] In summary, while existing technologies include self-powered tactile / pressure sensing, multimodal tactile devices, and electromagnetic / eddy current metal recognition schemes, a solution is still lacking that can achieve simultaneous output of "material (metal) identification of the contact object (including differentiation of different metal categories)" and "tactile pressure sensing" within the same compact stacked device without the need for an external excitation power supply, through a shared reference electrode. In particular, the following key technical contradictions need to be addressed: Under open-circuit potential difference (open-circuit voltage) output conditions, the material identification channel needs to maintain a stable low-resistance interface response to characterize material-related sensitive potential changes; while the tactile channel requires maintaining high resistance in the resting state to suppress internal discharge and stabilize the baseline, and achieving significant resistance variation and potential increment response through microstructure-induced contact state changes under pressure. Without a structural-level impedance gradient layered design and a load isolation mechanism under shared reference electrode conditions, the low-resistance recognition circuit is prone to forming a parallel load on the high-resistance tactile channel, causing tactile open-circuit potential difference signal attenuation, zero-point drift and output instability, thus making it difficult to meet the robot end effector's requirement for parallel output with the same source and high signal-to-noise ratio for "object attribute cognition + force control tactile feedback". Summary of the Invention

[0010] In view of this, the purpose of this invention is to provide a self-powered metal recognition and tactile pressure sensing integrated device, system and sensing method, which can generate an open-circuit potential signal based on the self-generated potential response of the electrode-ion conductive medium interface without the need for an external excitation power source. Under the same compact stacked structure and shared reference electrode conditions, it can output two types of signals simultaneously, representing the material properties of the contact object (including different metal categories) and the contact pressure / contact state. Through impedance layering, common electrode stabilization and encapsulation moisture management, the mutual loading and discharge effects between multimodal signals are reduced, improving output stability and engineering adaptability. It is suitable for robot end effectors, electronic skin and human-computer interaction scenarios.

[0011] To achieve the above objectives, the present invention provides the following technical solution: a self-powered metal recognition and tactile pressure sensing integrated device, comprising a first electrode stacked sequentially along the thickness direction. tactile sensitive layer Common electrode Metal recognition layer and located in the away from the common electrode One side of the recognition end Wherein: (a) the metal recognition layer With the common electrode and the identification terminal Electrical connection; when the identification terminal When in contact with the object being measured, at the common electrode With the identification end The first open-circuit potential difference (open-circuit voltage) signal, which characterizes the material of the object being tested, is generated between them. (b) the tactile sensitive layer It has a surface microstructure and exhibits high resistance in the absence of external force, and the tactile sensitive layer With the first electrode and the common electrode Electrical connection; when pressure is applied to the device, the microstructure deforms and increases the effective contact area between the electrode and the sensitive layer, making the... The equivalent impedance decreases, thereby reducing the impedance at the first electrode. With the common electrode A second open-circuit potential difference (open-circuit voltage) signal representing pressure is generated between them. (c) The common electrode At the same time with the above and stated Contact and as the With the The common reference electrode makes the first open-circuit potential difference (open-circuit voltage) signal In terminal pair – Output, the second open-circuit potential difference (open-circuit voltage) signal In terminal pair – Output; and in the initial state without external force, the The initial equivalent impedance is significantly greater than that of the The initial equivalent impedance.

[0012] Furthermore, the identification end To set in The conductive layer on the surface; or, the identification terminal. The test object, which is conductive, is in contact with the Equivalent to time.

[0013] Furthermore, in the initial state without external force and within the preset operating frequency band, the The initial equivalent impedance is not greater than The The initial equivalent impedance is not less than And satisfy: .

[0014] Furthermore, the microstructure includes microbumps, micropillars, microcones, microdomes, micropyramids, or corrugated stripe structures; the height of the microstructure is... The cycle is The and / or The invention comprises an ion-conducting medium, wherein the ion-conducting medium includes a polymer matrix and an electrolyte dispersed therein; the electrolyte is selected from at least one of inorganic salts, acids, bases, ionic liquids, and zwitterions.

[0015] Furthermore, the first electrode With the common electrode Made of different materials and / or with different surface treatments, and / or the common electrode. With the identification end Made of different materials and / or with different surface treatments; said surface treatment includes at least one of physical roughening, chemical modification, plasma treatment, noble metal modification or nanostructuring treatment.

[0016] Furthermore, the common electrode The core stacked structure has a stabilization layer, which includes at least one of a surface roughening layer, a surface microporous layer, an Ag / AgCl conversion layer, a conductive polymer coating, or a carbon-based coating, for reducing the baseline drift of the open-circuit potential difference (open-circuit voltage) signal. An encapsulation layer and / or a barrier layer are provided on the outside of the core stacked structure to suppress the loss of moisture from the internal ionic conductive medium and to block the influence of external humidity fluctuations on the stability of the open-circuit potential difference (open-circuit voltage) signal.

[0017] Furthermore, the device is an array structure to form a sensing surface with multiple spatial resolution units, and multiple sensing units share the same common electrode. Or shared common electrode in different areas Each sensing unit independently outputs its corresponding first open-circuit potential difference (open-circuit voltage) signal. The signal with the second open-circuit potential difference (open-circuit voltage) .

[0018] This invention also provides a self-powered metal recognition and tactile pressure sensing system, including the aforementioned integrated device; it further includes a signal acquisition module and a processing module; the signal acquisition module is used to input an impedance of not less than... The first open-circuit potential difference (open-circuit voltage) signal is acquired in this manner. With the second open-circuit potential difference (open-circuit voltage) signal The processing module is used to process the data according to the... Output material category information, and according to the... Output pressure value or contact status.

[0019] The input impedance of the signal acquisition module is not less than The system also includes an actuator and a control module; the processing module pre-stores pressure-signal calibration relationships and / or material classification models; the control module dynamically adjusts the pressure threshold of the actuator and performs adaptive grasping or touch operations based on the identified material type and pressure value or contact state.

[0020] This invention also provides a self-powered metal recognition and tactile pressure sensing method, which employs the integrated device or system described above. The method includes: 1) enabling the recognition end... Contact the object being tested to obtain a common electrode. With the identification end The first open-circuit potential difference (open-circuit voltage) signal between ;2) Apply pressure to the device to make the The microstructure undergoes deformation to obtain the first electrode. With common electrode The second open-circuit potential difference (open-circuit voltage) signal between ;3) Based on the above Output material property data, and based on the... The method outputs pressure data or contact status data to achieve synchronous sensing of material and pressure. The preset operating frequency band in this method is a low-frequency or mid-low-frequency band, preferably... any subinterval of .

[0021] The beneficial effects of this invention are as follows: The beneficial effects of this invention are as follows: This invention utilizes the "first electrode" / Touch-sensitive layer / Common Electrode / Metal recognition layer / Identification end The compact stacked structure employs a common electrode. As a common reference electrode, dual-mode output based on open-circuit potential signals is achieved without the need for an external excitation power supply; among which, the metal recognition layer Provides stable, low-resistivity interface response for outputting material-dependent values. tactile sensitive layer By utilizing surface microstructures to maintain high resistance in the resting state and controllably reduce resistance under pressure to output pressure-related parameters. Furthermore, by employing a pre-defined impedance gradient layered design, the parallel load effect of the low-resistance recognition circuit on the high-resistance tactile channel is reduced, mitigating signal attenuation and zero-point drift, and improving the stability and repeatability of the synchronous output of the two signals. Moreover, this invention achieves physical spatial overlap between the detection areas of material recognition and pressure sensing, reducing multimodal asynchrony issues caused by sensor misalignment during robot perception and control. Through common electrode stabilization and encapsulation / isolation design, baseline drift can be further reduced and environmental adaptability improved.

[0022] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the preferred embodiments of this invention will be described in detail below with reference to the accompanying drawings, in which: Figure 1 is a side view of the overall system structure, showing the positional relationships of the top electrode, high-resistivity dielectric layer (including microstructure), shared common electrode, low-resistivity dielectric layer, metal electrode under test, and clamp; Figure 2 shows the high-resistivity dielectric layer. With low-resistivity dielectric layer Figure 3 shows a schematic diagram comparing the equivalent impedance within a preset frequency band; Figure 4 shows the output potential difference between copper and aluminum as the two ends of a flexible medium, with the medium impedance changing; Figure 5 shows the interface change model after applying pressure; Figure 6 shows a bar chart of characteristic potential outputs for different metals, including 9 metals. The following figures illustrate the process: Figure 6 shows the metal recognition confusion matrix, based on the recognition accuracy of 1000 tests; Figure 7 shows the basic data corresponding to the tactile sensor, including response curves for different concentrations, response / recovery time, response under different loading forces and loading speeds, step response, and repeatability of 20,000 times; Figure 8 is a flowchart illustrating the dual-modal synchronous sensing and closed-loop control method provided in Embodiment 2 of the present invention; Figure 9 is a flowchart illustrating the pressure calibration and compensation method based on metal recognition signals provided in Embodiment 3 of the present invention; Figure 10 is a flowchart illustrating the operation of the self-powered metal recognition and tactile pressure sensing system provided in Embodiment 4 of the present invention; Reference numerals: 1- Top electrode; 2- High-resistivity dielectric layer; 3- Shared common electrode; 4- Low-resistivity dielectric layer; 5- The metal electrode to be tested; 6-conductive electrode. Detailed Implementation

[0024] The technical solution of the present invention will now be described in detail with reference to the accompanying drawings.

[0025] Please refer to Figures 1 to 6. The present invention provides a self-powered dual-mode sensing system based on dual-impedance dielectric layering and common electrode multiplexing, including a top electrode. High-resistivity dielectric layer Shared public electrodes Low-resistivity dielectric layer and the metal electrode to be tested Among them, the top electrode Conductively connected to an external actuator (e.g., a clamp), sharing a common electrode. As a common reference point for the tactile sensing module and the metal recognition module, the above structure enables the synchronous output of metal recognition signals by the same device. With tactile pressure signals .

[0026] Example 1: This example provides a simplified process of "non-woven fabric soaking—liquid control consistency—drying—layer assembly" to construct a high-resistivity dielectric layer within the same compact stacked device. With low-resistivity dielectric layer The impedance gradient, and in the shared common electrode Under the condition of synchronous output, the first open-circuit potential signal for identifying the metal type of the contact object is output. The second open-circuit potential increment signal of tactile pressure sensing The "open-circuit potential signal" mentioned in this embodiment refers to the potential difference between electrodes measured when the input impedance is much greater than the equivalent internal resistance of the signal source; it can also be called an open-circuit voltage signal. This embodiment is only used to illustrate the specific implementation of the present invention and does not constitute a limitation on the scope of protection of the present invention; where there is no conflict, the parameter window and features in this embodiment can be combined with each other.

[0027] 1) Device Structure and Material Selection: The device in this embodiment has a stacked structure, which includes, from top to bottom: top electrode High-resistivity dielectric layer / Common Electrode Low-resistivity dielectric layer / Bottom conductive electrode (serves as the identification end and forms an equivalent electrode in contact with the metal being measured) Among them, the common electrode At the same time with and Contact serves as a common reference electrode for both the tactile and recognition channels.

[0028] In this embodiment, the top electrode Aluminum foil is used as the common electrode. Copper foil is selected. The preferred electrode thickness is... More preferably The effective overlap area between the electrode and the dielectric layer is preferably... More preferably This ensures that the output signal is stable and easy to prepare and test repeatedly.

[0029] The and All use nonwoven fabric as the framework carrier for the ion-conducting medium. The preferred nonwoven fabric material is polypropylene (PP) or polyester (PET) nonwoven fabric; the preferred nonwoven fabric basis weight is... More preferably The preferred thickness of the nonwoven fabric (uncompressed) is... More preferably To enhance reproducibility, and It is preferable to use non-woven fabric substrates of the same batch and size.

[0030] 2) High-resistivity dielectric layer With low-resistivity dielectric layer The preparation (non-woven fabric soaking—liquid control—drying) aims to form an impedance gradient. In this embodiment, the same non-woven fabric substrate and the same drying procedure are used, with the preparation achieved only through differences in NaCl solution concentration. and .

[0031] (1) High-resistivity dielectric layer Take the first piece of nonwoven fabric and soak it in a NaCl aqueous solution, wherein the mass ratio of NaCl to water is 0.5% (fixed in this embodiment). The soaking time is preferably... More preferably This ensures the fiber network is fully wetted. After soaking, the nonwoven fabric is removed and subjected to a liquid control and standardization treatment. The preferred method is a combination of natural dripping and gentle scraping / pressing; more preferably, a repeatable mechanical liquid control method is used to achieve standardization, such as using an absorbent medium (absorbent paper / dust-free paper) to briefly press the soaked nonwoven fabric dry under constant pressure, so that... and The apparent liquid content before entering the drying stage is comparable, thereby reducing the exponential effect of moisture content differences on the equivalent impedance. Drying is then carried out, preferably under room temperature ventilation drying or... Drying, more preferably Drying; the preferred drying time is... More preferably Further optimization used "constant quality" as the drying endpoint criterion. After drying, the following was obtained: The elastic dielectric layer, which exhibits high resistance in a resting state without external force, is used to suppress leakage current and stabilize the tactile baseline.

[0032] (2) Low-resistivity dielectric layer Take a second piece of nonwoven fabric and soak it in a NaCl aqueous solution, wherein the mass ratio of NaCl to water is 3% (fixed in this embodiment). The soaking time, the method of consistent liquid control, and the criteria for determining the drying endpoint are optimized and... Maintain consistency. Obtained after drying. The elastic dielectric layer, due to its higher salt content, forms a more continuous ion conduction path and exhibits low resistance, supporting the rapid establishment and stable output of material-related potentials at the metal contact interface. Further preferably, the sample is placed in... Environmental stillness Perform water-bearing state equilibration to reduce initial drift.

[0033] 3) Component assembly and fixing Clamping / attaching to the top electrode of the aluminum foil Common electrode with copper foil Between them, a tactile channel is formed ( – – );Will Clamping / attaching to the copper foil common electrode A recognition channel is formed between the bottom conductive electrode and the electrode. – – The preferred preload pressure for the laminated assembly is... More preferably This ensures consistent bonding between layers and avoids over-compaction during assembly. This causes baseline shift.

[0034] To reduce the impact of moisture loss and environmental humidity disturbances on output stability, an encapsulation layer or edge seal structure can be provided on the outside of the device. The preferred encapsulation method is an elastic material edge seal or an integral encapsulation, and the preferred encapsulation layer thickness is... More preferably Further optimization of composite low water vapor permeability barrier membranes to improve long-term stability.

[0035] 4) Impedance gradient verification and "initial state" definition (corresponding to Figure 2): The impedance spectroscopy method is used to verify the impedance gradient. and The equivalent impedance is measured to verify whether the double impedance stratification is valid. The preferred frequency range for impedance spectrum measurement is... More preferably As shown in Figure 2, the scanning frequency range of this embodiment is... , respectively obtained and of With frequency Variation curve. The preferred test excitation amplitude is... More preferably This is to reduce polarization disturbances to the ion system.

[0036] To ensure the repeatability and comparability of the "initial equivalent impedance", the and The initial equivalent impedances were all measured under standardized clamping conditions; the clamping conditions are preferably a clamping state with a constant preload pressure, more preferably a clamping state consistent with the device assembly preload pressure, for example, taking... A constant preload pressure within a certain range is used as the benchmark test condition to reduce impedance shift in porous nonwoven fabrics caused by different compaction levels. It is preferable to perform the test under the same electrode area, the same preload pressure, and the same environmental conditions. and Comparative tests were conducted to reduce errors introduced by differences in contact resistance and water content.

[0037] As shown in Figure 2, within the scanning frequency band The overall equivalent impedance is significantly higher than The impedance ratio of the two signals satisfies a preset order of magnitude difference (preferably at least one order of magnitude higher), thereby forming a stable impedance gradient and providing an electrical basis for subsequent dual-mode signal splitting output.

[0038] Shared reference electrode In this structure, the tactile channel and the recognition channel can be equivalent to... There are two coupled branch networks at this point. If the signal source of the tactile channel is equivalent to an open-circuit potential source... With internal resistance By connecting them in series, the identification channel is equivalent to a low-impedance branch. Then, when measuring the input impedance When the voltage is sufficiently large (open-circuit acquisition), the degree to which the tactile potential is effectively maintained when measured externally can be qualitatively represented by "load shunt": when Much larger At that time, the charge / potential changes generated on the tactile side are more likely to occur in The interface is established and maintained, rather than via low resistance. The branch lines form significant discharge paths. Therefore, [the following is necessary:] [The following is a separate, unrelated sentence:] (At least one order of magnitude) can be used as a preferred criterion for achieving dual-channel physical layering and mutual interference suppression.

[0039] 5) Experimental Evidence for the Self-Powered Output Mechanism (corresponding to Figures 3 and 4): To illustrate the open-circuit potential output characteristics of this device under conditions without external excitation, this embodiment constructs an interfacial electrochemical open-circuit model formed by different electrode materials (e.g., copper / aluminum) and an ion-conducting medium. Under conditions without external bias voltage, the common electrode... A stable open-circuit potential difference can be spontaneously established between the electrode and the opposite electrode; as shown in Figure 3, the output change trend measured by changing the equivalent impedance of the dielectric / loading conditions is consistent with the interface self-generated potential model, indicating that the output signal is not caused by voltage distribution driven by an external power supply. Furthermore, when the input impedance of the signal acquisition module... When the value is sufficiently high, the measured output is closer to the open-circuit limit, thus verifying the necessity of the self-powered open-circuit acquisition condition.

[0040] In the identification channel, the identification end (which contacts the metal being measured to form an equivalent electrode) ) and common electrode The open-circuit potential between the electrodes can be determined by the difference in work function between the electrodes and the potential of the double layer at the interface, and can preferably be expressed as: in, , Equivalent electrodes With common electrode The work function, For elementary charge, This refers to the electric double-layer potential difference at the electrode-ion medium interface. Different metallic materials... Unlike the interface state, it makes It presents distinguishable material characteristics.

[0041] As shown in Figure 4, the tactile channel undergoes a change in interfacial contact state during compression: the external force compacts the fiber network, increases the effective contact area of ​​the interface, and triggers the reconstruction of ion distribution and double-layer state, thereby generating a pressure-related open-circuit potential increment. With the support of impedance gradient design, the potential increment is mainly in The side is established and preserved, reducing the risk of transmission via The possibility of charge discharge in low-resistance branches.

[0042] To meet the open-circuit acquisition requirements, the input impedance of the signal acquisition module... Preferred ≥ , more preferably ≥ Further optimization ≥ This is to reduce the loading effect of the acquisition circuit on the signal source.

[0043] 6) Metal Recognition Performance (corresponding to Figures 5 and 6) In the recognition channel, when the recognition end comes into contact with different metals, the metal recognition performance at the common electrode... An open-circuit potential signal related to the material is generated between the recognition end and the device. Figure 5 shows a histogram of characteristic potential outputs for nine metals, with different metals corresponding to... It presents a distinguishable step-like difference, which can be used to identify metal categories.

[0044] Figure 6 shows the material recognition confusion matrix obtained based on 1000 tests. It is used to characterize the recognition accuracy and main confusion pairs of different material categories under repeated testing conditions in this embodiment, and provides data support for the classification rules and threshold settings of the subsequent algorithm processing module.

[0045] 7) Tactile pressure response and durability assessment (corresponding to Figure 7) Tactile channels with As the core sensitive layer, pressure loading causes an increase in open-circuit potential. The loading force varies with the loading intensity. The preferred loading force range is... More preferably As shown in Figure 7, the loading force range in this embodiment is... The results include comparisons of response curves for samples of different concentrations, response / recovery times, responses under different loading forces and rates, step responses under stepped pressure inputs, and evaluations of cyclic stability (e.g., 20,000 cycles). These results indicate that... exist It can produce repeatable results within the range. It responds and maintains good stability and durability under cyclic loading conditions. In the tactile channel, Can be used as pressure The characterization parameters are preferably fitted using linear or piecewise linear calibration relationships, for example: in , These are the calibration coefficients determined through calibration experiments. For nonlinear response cases, polynomials or piecewise functions are preferred for establishing the calibration coefficients. and The correspondence.

[0046] Furthermore, to verify the dual-mode operation using a shared common electrode... This embodiment demonstrates parallel operation capability under certain conditions. While maintaining contact between the recognition end and the target metal, dynamic loading (within the range shown in Figure 7) is applied to the tactile channel. Tests show that the recognition channel... The baseline remained stable during haptic loading, and the haptic channels... The response pattern does not drift significantly due to contact recognition, indicating that the impedance gradient design and common electrode multiplexing structure described in this embodiment can achieve parallel output of dual signals and reduce mutual loading effects.

[0047] 8) Explanation of "Preset Operating Frequency Band": In this invention, the "preset operating frequency band" can be set according to the dispersion characteristics, structural dimensions, and input impedance matching relationship of the ion-conducting medium; preferably, the frequency band covers at least a portion of the impedance gradient verification frequency band shown in Figure 2 to ensure that the impedance ratio criterion can be verified and reproduced in actual operation. In this embodiment, the frequency band used for impedance gradient verification is... In practical applications, the preset operating frequency band can also preferentially select a sub-frequency band as the online determination and calibration frequency band.

[0048] Example 2 (Control Method: Dual-modal Synchronous Acquisition and Closed-Loop Force Control, corresponding to Figure 8) This example provides a control method for controlling the self-powered dual-modal sensing system described in Example 1, used to synchronously acquire metal recognition signals during robot end-effector interaction. With tactile pressure signals An adaptive force control closed loop is achieved based on the recognition results and pressure estimation. Please refer to Figures 4–7 (signal features and tactile data).

[0049] More specifically, the control method described in this embodiment includes the following steps: Step 1: Synchronous acquisition and high-resistance measurement condition setting. The signal acquisition module is used to measure the top electrode. Shared public electrode The tactile channel potential signal between them, and the metal electrode under test Shared public electrode The potential signals of the identification channels are synchronously acquired; to meet the prerequisite of open circuit potential measurement, the input impedance of the signal acquisition module is... Preferably configured to be significantly greater than the equivalent internal resistance of the sensing source (further preferred) More preferably This is to suppress the load effect and stabilize the readout of the self-generated open-circuit potential signal.

[0050] Step 2: Signal Preprocessing. The acquired raw potential sequence will undergo preprocessing, which includes at least: normalization, noise reduction, and time window division. Noise reduction can be achieved using digital low-pass filtering, with the preferred cutoff frequency being [missing information]. And a unified clock is used for synchronous sampling to reduce phase error (preferably phase error). ).

[0051] Step 3: Metal Identification and Pressure Estimation (1) Metal Identification: Based on Metal Identification Signals Material identification is performed using a physical model, among which... It is determined by both the work function difference and the double-layer potential difference: In the formula, , These are the electrode work functions, For elementary charge, This represents the double-layer potential difference. Combining the characteristic potential distributions of different metals shown in Figure 5 with the confusion matrix results shown in Figure 6, the metal category to be tested is output.

[0052] (2) Pressure estimation: based on tactile channel signals The calibration relationship is obtained under pressure : in , The calibration coefficients are preferably satisfied, and the linear fit goodness of fit is preferably satisfied. .

[0053] Step 4: Threshold Determination and Control Execution. Based on the calibrated threshold, determine whether the current pressure meets the interaction / grabbing requirements. If it does, continuously collect and update the identification and pressure estimation. If it does not meet the requirements, generate a control signal to instruct the control execution module to adjust the actuator (e.g., clamp current or drive displacement) to change the force, and enter the feedback update process.

[0054] Step 5: The closed-loop feedback update control execution module preferably uses a proportional-integral (PI) control law to achieve closed-loop regulation, and its control output... for: in This is the proportionality coefficient. The integral coefficient is... To control errors, the system response time is optimized. .

[0055] Finally, it should be noted that this embodiment enables the system to achieve a "recognition-sensing-control" closed loop without the need for external excitation through the "synchronous acquisition - identification / estimation - threshold determination - PI closed-loop adjustment" link.

[0056] Example 3 (Calibration and Algorithm: Material Reference Driven Pressure Compensation and Discrimination, corresponding to Figure 9) This example provides a calibration and algorithm processing method for the system described in Example 1, which improves the robustness of metal identification and pressure estimation under dual-modal synchronous output conditions and further reduces the impact of crosstalk. Please refer to Figures 4–7.

[0057] More specifically, this embodiment includes the following steps: Step 1: Establish a metal identification reference library and select various metal materials to be tested, so that the metal electrode to be tested... Shared public electrode A stable contact is formed through a low-resistivity dielectric layer, and the open-circuit potential signal of the identification channel is acquired under conditions without external bias. The characteristic potentials of different metals were statistically analyzed to form a reference library; Figure 5 shows the library containing 9 metals. Example of a columnar distribution.

[0058] Step 2: Construct a metal classifier and validate the collected data. The feature input classification module outputs the metal category; the classification result can be evaluated using the confusion matrix, and Figure 6 shows the recognition accuracy matrix based on 1000 tests.

[0059] Step 3: Pressure Calibration and Fitting. Different pressure loads are applied to the device in the tactile channel, and data are collected. After fitting and calibration, the pressure estimation formula is obtained: And make the best fit condition satisfy The response curves of the tactile channel, different loading forces / loading rates, step response and cyclic stability can be found in Figure 7.

[0060] Step 4: The material reference-driven compensation (preferred) processing module, based on the metal identification results output in Step 1 / 2, assigns the corresponding metal... The baseline value serves as a reference for the system's operating point, adaptively correcting the sensitivity coefficient or zero-point drift of the pressure channel to reduce system errors caused by cross-material contact (e.g., for...). , (By performing material condition segmentation or table lookup updates), the cross-material consistency of the pressure estimation shown in Figure 7 is improved.

[0061] Finally, it should be noted that in this embodiment, the "material benchmark" is established using Figures 5-6 and the "pressure calibration" is established using Figure 7, so that the dual-modal integration is reflected not only at the structural level but also at the algorithm level.

[0062] Example 4 (Control System: Integrated Hardware Link for Acquisition-Processing-Execution, corresponding to Figure 10) This example provides a control system for the self-powered dual-modal sensing system described in Example 1, which is used to realize the closed-loop deployment of "identification-perception-control" and is suitable for scenarios such as robot end effectors.

[0063] More specifically, the control system described in this embodiment includes: a power supply, a signal acquisition module, an algorithm processing module, a control execution module, and an actuator; wherein the power supply is self-powered, the signal acquisition module is connected to the wires led out from the electrodes, the algorithm processing module communicates with the host computer, and the control execution module is connected to the actuator and performs control law adjustment.

[0064] The workflow of this embodiment is as follows: Step 1: System wiring and synchronous sampling configuration (connecting the tactile channel) – ) and identification channel ( – Each signal is connected to a signal acquisition module; the acquisition module preferably uses a 16-bit synchronous ADC and samples synchronously according to a unified clock.

[0065] Step 2: Algorithm processing and dual-modal solution. After preprocessing the synchronous sampling data, the algorithm processing module outputs: (1) Metal category: based on (2) Stress estimation: based on The results are then sent to the control execution module.

[0066] Step 3: Control Execution and Feedback Closed-Loop Control Execution Module generates an error based on the target force / target state and the current estimate. And output the control quantity through a PI control law: By adjusting the force of the actuator, the system response time can be optimized. .

[0067] This embodiment integrates sensors, acquisition circuits, algorithm calculations, and execution control into a deployable system, thereby achieving stable dual-modal synchronous sensing and adaptive control at the robot's end effector. The "open-circuit potential signal" mentioned in this embodiment can also be called an "open-circuit voltage signal," referring to the potential difference between electrodes measured under open-circuit measurement conditions (i.e., the input impedance of the signal acquisition module is much greater than the equivalent internal resistance of the signal source).

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications should be covered within the scope of the claims of the present invention.

Claims

1. A self-powered metal recognition and tactile pressure sensing integrated device, characterized in that: Includes a first electrode stacked sequentially along the thickness direction. tactile sensitive layer Common electrode Metal recognition layer and located in the away from the common electrode One side of the recognition end Wherein: (a) the metal recognition layer With the common electrode and the identification terminal Electrical connection; when the identification terminal When in contact with the object being measured, at the common electrode With the identification end The first open-circuit potential difference signal, characterizing the material of the object being tested, is generated between them. (b) the tactile sensitive layer It has a surface microstructure and exhibits high resistance in the absence of external force, and the tactile sensitive layer With the first electrode and the common electrode Electrical connection; when pressure is applied to the device, the microstructure deforms and increases the effective contact area between the electrode and the sensitive layer, making the... The equivalent impedance decreases, thereby reducing the impedance at the first electrode. With the common electrode A second open-circuit potential difference signal representing pressure is generated between them. (c) The common electrode At the same time with the above Japanese Contact and as the With the The common reference electrode makes the first open-circuit potential difference signal In terminal pair – Output, the second open-circuit potential difference signal In terminal pair – Output; and in the initial state without external force, the The initial equivalent impedance is significantly greater than that of the The initial equivalent impedance.

2. The self-powered metal recognition and tactile pressure sensing integrated device according to claim 1, characterized in that: The identification end To set in The conductive layer on the surface; or, the identification terminal. The test object, which is conductive, is in contact with the Equivalent to time.

3. The self-powered metal recognition and tactile pressure sensing integrated device according to claim 2, characterized in that: In the initial state without external force and within the preset operating frequency band, the The initial equivalent impedance is not greater than The The initial equivalent impedance is not less than And satisfy: 。 4. The self-powered metal recognition and tactile pressure sensing integrated device according to claim 3, characterized in that: The microstructure includes microbumps, micropillars, microcones, microdomes, micropyramids, or corrugated stripe structures; the height of the microstructure is... The cycle is The and / or The invention comprises an ion-conducting medium, wherein the ion-conducting medium includes a polymer matrix and an electrolyte dispersed therein; the electrolyte is selected from at least one of inorganic salts, acids, bases, ionic liquids, and zwitterions.

5. The self-powered metal recognition and tactile pressure sensing integrated device according to claim 4, characterized in that: First electrode With the common electrode Made of different materials and / or with different surface treatments, and / or the common electrode. With the identification end Made of different materials and / or with different surface treatments; said surface treatment includes at least one of physical roughening, chemical modification, plasma treatment, noble metal modification or nanostructuring treatment.

6. The self-powered metal recognition and tactile pressure sensing integrated device according to claim 5, characterized in that: The common electrode The system has a stabilization layer, which includes at least one of a surface roughening layer, a surface microporous layer, an Ag / AgCl conversion layer, a conductive polymer coating, or a carbon-based coating, for reducing the baseline drift of the open-circuit potential difference signal; an encapsulation layer and / or a barrier layer are provided on the outside of the core stacked structure to suppress the loss of moisture from the internal ionic conductive medium and to block the influence of external humidity fluctuations on the stability of the open-circuit potential difference signal.

7. The self-powered metal recognition and tactile pressure sensing integrated device according to claim 6, characterized in that: The device is an array structure to form a sensing surface with multiple spatial resolution units, and multiple sensing units share the same common electrode. Or shared common electrode in different areas Each sensing unit independently outputs its corresponding first open-circuit potential difference signal. With the second open-circuit potential difference signal 。 8. A self-powered metal recognition and tactile pressure sensing system, characterized in that: The device includes an integrated device as described in any one of claims 1 to 7; it also includes a signal acquisition module and a processing module; the signal acquisition module is used to input an impedance not less than... The first open-circuit potential difference signal is acquired in this way. With the second open-circuit potential difference signal The processing module is used to process the data according to the... Output material category information, and according to the... Output pressure value or contact status.

9. The self-powered metal recognition and tactile pressure sensing system according to claim 8, characterized in that: The input impedance of the signal acquisition module is not less than The system also includes an actuator and a control module; the processing module pre-stores pressure-signal calibration relationships and / or material classification models; the control module dynamically adjusts the pressure threshold of the actuator and performs adaptive grasping or touch operations based on the identified material type and pressure value or contact state.

10. A self-powered metal recognition and tactile pressure sensing method, characterized in that, The method employs an integrated device or system as described in any one of claims 1 to 9, the method comprising: 1) enabling the identification end Contact the object being tested to obtain a common electrode. With the identification end The first open-circuit potential difference signal between them ;2) Apply pressure to the device to make the The microstructure undergoes deformation to obtain the first electrode. With common electrode The second open-circuit potential difference signal between ;3) Based on the above Output material property data, and based on the... The method outputs pressure data or contact status data to achieve synchronous sensing of material and pressure. The preset operating frequency band in this method is a low-frequency or mid-low-frequency band, preferably... any subinterval of .

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