CN110772247A - Sensing device for synchronous and apposition detection of bioelectric signals and pressure signals - Google Patents

Abstract

The invention discloses a sensor for detecting biological electrical signals and pressure signals, which comprises a pressure sensitive layer and an electrical signal conducting layer, wherein the electrical signal conducting layer includes at least one electrode. Wherein, the pressure sensitive layer can sense pressure and convert the pressure into an electrical signal, and the electrical signal conducting layer can collect the electrical signal and conduct the electrical signal through the electrode.

Description

A sensor device for simultaneous detection of bioelectrical signals and pressure signals

technical field

The present invention relates to the field of sensor technology. In particular, the present invention relates to a sensing device for synchronously detecting bioelectrical signals and pressure signals at the same location.

Background technique

The potential and polarity changes of organs, tissues, and cells of organisms in the process of life activities, and the extensive and complex bioelectric phenomena in organisms can reflect some physical and chemical changes in the process of life activities. For example, in the absence of irritable excitation, there is a potential difference between different parts of a biological tissue or cell, that is, a resting potential. When stimulated, living organisms produce stress, and cell metabolism or function changes, which in turn produces potential changes, that is, bioelectrical signals. For example, for plants, when the plant tissue is bent or folded (mechanical stimulation), it can cause potential changes of tens of millivolts; plants also have potential changes in photosynthesis, which is an electrical response caused by metabolic changes. . In animals, nerve impulses are conducted in the form of electrical signals. During the movement of animal muscles, electrical signals are also generated on the surface of muscle tissue.

Under certain conditions, in a statistical sense, these bioelectrical signals are regular, that is, certain physiological processes often correspond to certain electrical responses. Therefore, in some applications, the state of the physiological process can be inferred according to the changes of bioelectricity, such as the detection of bioelectrical information such as electrocardiogram, electroencephalogram, and electromyogram.

In addition, the life activities of organisms also generate stress signals. For example, when breathing, the pressure in the abdominal cavity changes; when sleeping, the head pressure changes caused by different sleeping positions; when exercising, the muscle surface pressure changes caused by the deformation caused by muscle contraction, and the pressure changes between different limb positions and the ground caused by exercise, etc. . Detecting pressure changes between an organism and the external environment can reflect the physiological activity state of an organism, and is also an important means of monitoring and evaluating human health-related indicators and exercise conditions.

Existing bioelectric signal sensing technologies can be divided into two categories: invasive sensing and non-invasive sensing. The sensor of invasive sensing is generally needle type or hook type, which can be surgically implanted into the site to be tested or directly inserted into the site to be tested in the body to conduct electrical signals, and can be used to record deep, smaller muscles, nerves Waiting for the discharge, the physiological process of the organism can be inferred according to the change of the bioelectrical signal. The disadvantage of this method is that it is invasive, has a greater impact on the health of the organism, is complicated to use, and has a high cost. Non-invasive sensing utilizes the phenomenon that the electrical signals generated by the physiological activities inside the organism will be transmitted to the body surface and cause the corresponding electrical signal response on the body surface. Generally, a conductive medium is used to connect the surface of the organism to be measured due to the physiological activity. electrical signals are transmitted.

In the prior art, when using non-invasive electrical signal sensing technology for bioelectrical signal detection, there are the following problems, including: the bioelectrical signal itself is easily disturbed by itself and the environment, for example, between the site to be measured and the electrode Motion artifacts caused by tiny movements, bioelectric signals themselves are easily affected by surrounding electrical and magnetic interference, easily affected by ambient temperature, humidity, and easily affected by the organism itself (such as sweating, etc.), and the physiological state of the organism is determined by Therefore, it is difficult to obtain accurate detection. At the same time, signal crosstalk between different tissues (eg muscle fibers) can also cause high signal distortion. The reproducibility of surface bioelectrical signals is difficult due to the influence of multiple sources of interference and small differences in the positioning of electrodes during multiple measurements, and its placement is also difficult due to differences in the tissue structure (e.g., muscles) of different users. Difficult to standardize.

In addition, in the prior art, when the detection of the bioelectrical signal and the pressure signal needs to be applied at the same time, if simultaneous detection is required, the detection points of the bioelectrical signal and the pressure signal cannot be located at the same location, that is, the same location detection cannot be achieved; If co-location detection is required, one type of signal needs to be measured before another type of signal, that is, synchronous detection cannot be achieved. For example, in the paper "Exploration of Force Myography and surface Electromyography in handgesture classification" (Medical Engineering & Physics, 2017.41: 63-73), the recent research results of Jiang X et al. in the field of electromyography were reported, which disclosed a synchronous acquisition of muscle The device for electricity and pressure is shown in Figure 1. In Figure 1, each pair of electrodes is used to collect EMG signals, and the wristband part on the left is provided with a pressure signal detection sensor. In this way, under the unified clock, the EMG signal and the pressure signal can be detected synchronously, but the co-location detection of the two cannot be achieved, and it is difficult to eliminate the influence of changes in environmental conditions during the detection process.

Therefore, there is an urgent need for a sensor device and measurement method that can realize synchronous and isotopic detection of bioelectrical signals and pressure signals, can flexibly adapt to sensitivity and range, and is relatively robust to environmental influences.

SUMMARY OF THE INVENTION

The present invention proposes a sensor device for synchronously detecting bioelectrical signals and pressure signals, which can well solve the above-mentioned problems in the prior art. In order to achieve this purpose, the present invention adopts the following technical solutions:

A sensor for detecting bioelectrical signals and pressure signals, comprising: a pressure-sensitive layer; an electrical signal conducting layer comprising at least one electrode; wherein the pressure-sensitive layer can sense pressure and convert the pressure into electricity signal; the electrical signal conducting layer can collect the electrical signal and conduct the electrical signal through the electrode.

In a further embodiment, the pressure-sensitive layer and the electrical signal conducting layer are bonded together to form a sheet-like whole that can be closely attached to the surface of a living body.

In a further embodiment, the electrical signal conducting layer includes a pressure signal conducting layer and a bioelectrical signal conducting layer, the pressure sensitive layer is laminated with the pressure signal conducting layer to form a pressure sensing layer, and the pressure sensing layer An insulating layer is provided between the layer and the bioelectrical signal conducting layer.

In a further embodiment, the pressure sensitive layer is one or more of a resistive pressure sensitive layer, a capacitive pressure sensitive layer, a piezoelectric pressure sensitive layer, and a triboelectric pressure sensitive layer.

In a further embodiment, the capacitive pressure sensitive layer includes at least one electrode, and the pressure sensitive layer includes a layer of ionic material that is deformed by external pressure, thereby affecting the capacitance formed by the electrode.

In a further embodiment, the pressure sensitive layer, the pressure signal conducting layer and the insulating layer enclose an enclosed or non-enclosed chamber.

In a further embodiment, the pressure signal conducting layer is formed with one or more protrusions and/or depressions on the surface of the portion inside the chamber.

In a further embodiment, the capacitive pressure sensitive layer includes at least two patterned electrodes, wherein the at least two patterned electrodes are separate electrodes that are electrically insulated from each other.

In a further embodiment, the patterned electrodes are comb electrodes, wherein the comb electrodes are arranged to intermesh but not contact each other.

In further embodiments, the pressure sensitive layers and the electrical signal conducting layers are stacked in any number and order.

As can be seen from the above content, the present invention describes a sensor device and measurement method capable of synchronously detecting bioelectrical signals and pressure signals, flexibly adaptable in sensitivity and range, and relatively robust to environmental impact. Advantages of the present invention include, but are not limited to, being able to achieve simultaneous and co-located detection of bioelectrical signals and pressure signals. The method and device involved in the present invention are particularly suitable for identifying, monitoring and analyzing the motion state of human and animal body by measuring the electromyographic signal and pressure signal of the human body.

The details of some exemplary embodiments of the invention are set forth in the accompanying drawings and the detailed description below. Other features and advantages will be apparent from the description of the drawings and detailed description and claims.

Description of drawings

1 illustrates a schematic diagram of a device for synchronously detecting electromyographic signals and pressure signals in the prior art;

Figure 2 illustrates a simplified schematic diagram of a sensor principle according to an embodiment of the invention;

FIG. 3 illustrates a schematic diagram of an exemplary electromyographic signal acquisition scheme according to an embodiment of the present invention;

FIG. 4 illustrates a schematic diagram of a sensor implemented using a shared solution according to an embodiment of the present invention;

5 illustrates a schematic diagram of a sensor implemented using a split-type scheme according to an embodiment of the present invention;

6 illustrates a schematic diagram of a sensor with a chamber structure according to an embodiment of the present invention;

7 illustrates a schematic diagram of a single-electrode sensor according to an embodiment of the present invention;

8 illustrates a schematic diagram of a composite sensor according to an embodiment of the present invention;

9 illustrates a schematic diagram of a stacked structure and a staggered structure according to an embodiment of the present invention;

Figure 10 illustrates a sensor configuration in a multi-electrode form according to an embodiment of the present invention;

Figure 11 illustrates some examples of pressure sensitive layers with protrusions in accordance with embodiments of the present invention;

12 illustrates a schematic diagram of a comb-shaped meshing electrode according to an embodiment of the present invention;

Figure 13 illustrates a schematic diagram of some variations of a sensor according to an embodiment of the invention;

14 illustrates an exploded schematic view of a capacitive sensor according to an embodiment of the present invention;

15 illustrates a schematic diagram of an electric double layer structure according to an embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the exemplary embodiments of the present application, and are not exhaustive. Based on the embodiments in this application, it is not difficult for those skilled in the art to make other possible combinations of the technical features and means in these embodiments together with the prior art, and the technical solutions of all other embodiments obtained in this way fall within the scope of If they fall into the spirit and scope of the present application, they all belong to the intended protection scope of the present application.

The present invention can be implemented in many ways, eg as an apparatus, a method, a computer program product. Generally, unless otherwise stated or logically necessary, the order of the steps of the disclosed processes may be varied within the scope of the invention.

A detailed description of embodiments of the present invention is provided below in conjunction with the accompanying drawings that illustrate the principles of the present invention. While the invention is described in conjunction with such embodiments, the invention is not limited to any embodiment. Numerous specific details are set forth in the following detailed description in order to provide a thorough understanding of the present invention. The details are provided for the purpose of example, however, the invention may be practiced according to the claims without some or all of these specific details. For the purpose of clarity, techniques that are known in the technical fields related to the invention have not been described in detail so as not to obscure the invention.

The invention discloses a sensing device for synchronously detecting bioelectrical signals and pressure signals. As shown in FIG. 2, the sensor may include a pressure sensitive layer and an electrical signal conducting layer, wherein the electrical signal conducting layer includes at least one electrode. During operation, the electrical signal conducting layer is in direct contact with the site to be measured, and can conduct the generated electrical signal. The pressure sensitive layer is located on (preferably, attached to) the upper part of the electrical signal conducting layer.

Organs, tissues and cells of organisms may undergo potential changes in the process of life activities, which is a manifestation of normal physiological activities and a basic feature of biological living tissues. For example, during the movement of animal muscle tissue, potential differences are generated at different points on the surface of the muscle tissue. This potential difference will pass through the skin of the site to be measured and be captured by the electrodes of the electrical signal conduction layer attached to the site to be measured, and then the potential difference signal will be transmitted to the detection instrument to realize the detection of bioelectrical signals. monitor. Preferably, the pressure-sensitive layer and the electrical signal conducting layer are attached into a sheet-like whole, and the sheet-shaped whole is convenient to be attached to the surface of a living body. Preferably, both the pressure-sensitive layer and the electrical signal conducting layer are made of flexible materials, so as to satisfy good adhesion with the living body. The pressure sensitive layer can be solid, liquid, or composite. The material of the pressure-sensitive layer undergoes micro-displacement under the action of the pressure of the part to be measured, which in turn changes the physical and chemical properties of the pressure-sensitive material, which in turn generates changes in electrical signals, causing changes in the electrical signals of the conductive layer, which are further transmitted by the conductive layer. The electrical signal conducting layer can be solid, liquid, or composite material, such as metal, conductive liquid, conductive film, conductive fabric, graphene, and the like. There may be insulating materials around the electrical signal conducting layer or a conductive medium may be attached to the insulating material to form the electrical signal conducting layer. The electrical signal conducting layer may be a conductive surface of a film. Conductive surfaces can be implemented in a variety of ways, such as electrically active conductive surfaces and various conductive materials, such as thin-film indium tin oxide (ITO), or by proton doping of different oxidation states of the active material. The electrical signal conduction layer can also be made of metal materials (such as gold, aluminum, silver, copper, iron, etc., and their alloys, liquid metal mercury, gallium alloys and other metals); nanostructures (such as single-atom conductors, nanotubes, nanoparticles, etc.) and nanowires, etc.); non-metallic particles (such as carbon black, graphene, carbon nanotubes, carbon fullerene zinc oxide nanowires, indium oxide, germanium silicon, gallium arsenide, etc.); some conductive organic materials ( Such as polyphenylenedioxythiophene (3,4-enthy lenedioxythiophene), polystyrene sulfonate (PEDOT:PSS), polyaniline (PANI), poly(3-hexylthiophene-2,5-diyl) (P3HT) ) conductive polymers, and combinations of these materials. The insulating layer material can be a variety of non-conductive materials, including SU-8 glue, glass, polymers, Avatrel, double-sided tape, plastic, BCB PPA (benzocyclobutene) , polyimide, silicone rubber (PDMS), polymethyl methacrylate. Preferably, the insulating layer can be made of a flexible insulating material, which is convenient for conducting the pressure of the tested part.

Bioelectrical signals that are widely concerned at present include, for example, electromyography, electroencephalography, electrocardiogram, and oculoelectricity. It has become one of the hotspots in human-computer interaction research by decoding human bioelectrical signals to recognize human behavior, and then endow robots with the ability to understand human intentions. Surface EMG is the result of comprehensive superposition in time and space on the skin surface after the action potential sequences emitted by multiple active motor units propagate along the muscle fibers and filter through the volume conductor composed of fat/skin. FIG. 3 illustrates a schematic diagram of an exemplary electromyographic signal acquisition scheme according to an embodiment of the present invention. Before performing EMG acquisition, you can first select an appropriate electrode placement site on the muscle surface, and clean the skin surface (such as removing hairs, wiping with alcohol, etc.). The EMG signal captured by the surface electrode is first amplified by the amplifier circuit, and then input to the computer through A/D conversion. The recognition result can be used for, for example, realizing human-computer interaction control or analyzing the movement of the living body.

In some embodiments, the electrical signaling layer may include a pressure signaling layer and a bioelectrical signaling layer. The pressure signal conducting layer and the bioelectrical signal conducting layer may be insulated from each other. The pressure signal conducting layer is used for conducting electrical signals (eg, potential changes) generated by pressure, and the bioelectrical signal conducting layer is used for conducting electrical signals (eg, potential changes) generated by a living body. In this solution, the pressure signal conducting layer and the bioelectric signal conducting layer are electrically insulated, and the pressure signal conducting layer and the bioelectric signal conducting layer respectively conduct the pressure signal and the bioelectric signal generated at the same site, which are referred to herein as For the split-type scheme. On the contrary, the pressure signal (such as the potential difference signal due to pressure) and the bioelectrical signal generated at the same site can also be transmitted in the same conductive layer, and this scheme is referred to as a shared scheme in this paper.

4 illustrates a schematic diagram of a sensor implemented using a shared solution according to an embodiment of the present invention, wherein from top to bottom are a front view, a left view, and a top view of the sensor in order. The sensor includes a pressure-sensitive layer and a conductive layer, wherein the pressure-sensitive layer can be a whole piece of pressure-sensitive material, and the conductive layer includes left and right parts (or more parts) attached to the pressure-sensitive layer, and these parts form two one or more electrodes. When the pressure-sensitive layer is subjected to pressure, an electrical signal is generated, which is conducted through the conductive layer to the detection device. In some embodiments, the pressure-sensitive layer can be a piezoelectric pressure-sensitive layer that, when subjected to pressure, can produce a potential change corresponding to the magnitude of the pressure, the potential change passing through two or more electrodes of the conductive layer It is transmitted to the detection device, so that the magnitude of the pressure can be detected. In some embodiments, the pressure-sensitive layer can be a capacitive pressure-sensitive layer, which can produce a capacitance change corresponding to the magnitude of the pressure when subjected to pressure, and can be applied between two or more electrodes of the conductive layer There is a constant voltage, and the instantaneous current caused by the change of the capacitance under the constant voltage is conducted to the detection device, so that the magnitude of the pressure can be detected. In addition, the pressure-sensitive layer can also be one or more of a resistive pressure-sensitive layer, a Hall-type pressure-sensitive layer, a triboelectric pressure-sensitive layer, etc., all of which can be active or passive. The pressure is converted into a detectable electrical signal to measure the pressure experienced by the site in real time.

In some embodiments, the pressure signal and the bioelectric signal (eg, myoelectric signal) transmitted on the same channel can be extracted according to their respective signal characteristics and using a targeted acquisition method to extract the pure pressure signal and the pure bioelectric signal .

For example, due to the different frequency characteristics of the pressure signal bioelectrical signal, the common type can obtain different frequency components of the electrical signal by filtering the electrical signal. For example, when measuring EMG and pressure, the effective EMG spectrum is about 20 to 500 Hz, while the effective spectrum range of the stress signal is mainly distributed within 20 Hz. In some embodiments, a filtering operation may be applied to separate the pressure signal component and the bioelectrical signal component.

In other embodiments, when the pressure-sensitive layer is actively driven (for example, when the pressure-sensitive layer is a resistive pressure-sensitive layer or a capacitive pressure-sensitive layer, etc.), high-frequency sampling can be used to make the electrical signal It is distributed at intervals with the pressure signal sampling points to achieve synchronous and co-located detection. Specifically, for example, the power source of the pressure-sensitive layer can be turned off at odd-numbered sampling points, so that the detected electrical signal is only a bioelectrical signal, and the power source of the pressure-sensitive layer can be turned on at even-numbered sampling points, so that the detected electrical signal is only a bioelectrical signal. The signal is the sum of the pressure signal and the bioelectric signal. Since the pressure signal at adjacent sampling points is almost unchanged under high-frequency sampling (such as 1000Hz), and the pressure signal is usually a DC signal, the bioelectrical signal is usually an AC signal, and its effective spectral range is also much higher than that of the pressure signal. This feature can be used to estimate the magnitude of the pressure signal at odd sampling points. For example, the pressure signal at odd sampling points can be regarded as the mean or median of the sum of the pressure signal and the electromechanical signal in a certain neighborhood. In some embodiments, the DC nature of the pressure signal and the AC nature of the bioelectric signal can also be utilized to separate the pressure signal and the bioelectric signal. As an alternative to the odd-even sampling method in the above solution, the bioelectric signals of n points and the sum of pressure signals and bioelectric signals of m points (m, n are configurable positive integers) can also be collected alternately. Other arbitrary alternate acquisition methods can also be used, and the subsequent signal processing process can extract pure pressure and pure EMG signals according to this law.

FIG. 5 illustrates a schematic diagram of a sensor implemented using a split type solution according to an embodiment of the present invention, wherein from top to bottom are a front view, a left view, and a top view of the sensor in order. In some embodiments, the sensor includes a pressure signal conducting layer, a pressure sensitive layer and a bioelectric signal conducting layer, wherein the bioelectric signal conducting layer and the pressure signal conducting layer each include two separate electrodes, respectively attached to the pressure sensitive layer Both sides of the layer (which itself is an insulating material, eg can be made of natural rubber pressure sensitive adhesive, synthetic rubber pressure sensitive adhesive, thermoplastic elastic pressure sensitive adhesive). The conductive layer can be wrapped with insulating material to reduce contact with the environment and enhance the stability and robustness of the sensor. In some embodiments, two or more electrodes of the pressure signal conducting layer are in contact with the pressure sensitive layer on the site to be measured, collect electrical signals generated by pressure changes, and transmit the electrical signals through the pressure signal conducting layer In order to measure the pressure signal of the site to be measured; one side of two or more electrodes of the bioelectrical signal conducting layer is in contact with the site to be measured (eg skin) on the living body, and the other side of the bioelectrical signalling layer One side is in contact with the pressure sensitive layer, so the electrical signal transmission layer collects the sum of the pressure signal and the bioelectrical signal, and the bioelectrical signal can be obtained by subtracting the electrical signal detected by the pressure signal transmission layer.

In some embodiments, an insulating layer is provided between the bioelectrical signal conducting layer and the pressure sensitive layer, two or more electrodes of the pressure signal conducting layer are in contact with the pressure sensitive layer on the site to be measured, and pressure changes are collected The generated electrical signal is transmitted through the pressure signal conducting layer to measure the pressure signal of the site to be measured. The two or more electrodes of the bioelectrical signal conducting layer are in contact with the site to be measured (eg, skin) on the living body in order to measure the bioelectrical signal of the site to be measured.

In further embodiments, insulating materials may be filled between two or more electrodes of the pressure signal conducting layer, and between two or more electrodes of the bioelectric signal conducting layer, to provide In order to avoid impurities between the electrode pairs and affect the insulation performance between the electrodes.

6 illustrates a schematic diagram of a sensor with a chamber structure according to an embodiment of the present invention, wherein from top to bottom are a front view of the sensor in an unpressed state and a front view of the sensor in a pressurized state, respectively. Compared with the previous embodiments, the sensor described in FIG. 6 is provided with a chamber surrounded by an insulating layer between the pressure signal conducting layer and the pressure sensitive layer. In the absence of pressure or the pressure has not yet reached the threshold, the pressure signaling layer and the underlying pressure sensitive layer are separated by a chamber. Under the action of pressure, the pressure signal conducting layer is in contact with the pressure sensitive layer, and the pressure sensitive layer is subjected to physical or chemical changes caused by pressure to generate electrical signals, which can then pass through the pressure signal conducting layer (for example, two of the pressure signal conducting layers). or more electrodes) are transmitted out. After adding the design of the chamber, the tiny pressure is no longer expressed as an electrical signal output, but only when the pressure exceeds a certain threshold, the pressure signal can be output. This specific threshold can be adjusted to match specific application requirements by changing the thickness of the chamber, the stiffness of the pressure signal conducting layer, etc. Although only the insulating layers are shown on the left and right sides in the figures, in practical applications, more insulating layer strips may be arranged (eg, in the middle of the chamber of FIG. 6 ). The inner surface of the pressure-sensitive layer may also have any shape of protrusions and/or depressions, such as semicircles, triangles, etc., to achieve contact with the pressure signal conducting layer under different conditions. The chamber can be a vacuum chamber, can also be filled with any suitable dielectric such as special insulating gas, air, insulating liquid, etc., or can be a non-closed chamber.

In a further embodiment, the inner surface of the pressure signal conducting layer may also be provided with conductive protrusions and/or depressions (eg, semi-circles, triangles, etc.) to make the pressure signal conducting layer easier to contact with the pressure sensitive layer.

7 illustrates a schematic diagram of a sensor according to an embodiment of the present invention, wherein from top to bottom are a front view, a left view, and a top view of the sensor. Compared with the previous embodiments, the biggest feature of the sensor structure is that the bioelectrical signal conducting layer is a whole and is not divided into two or more electrodes, that is, the electrical signal conducting layer of the sensor only includes one electrode. The difference between a sensor with a single electrode electrical signal conduction layer and a sensor with multiple electrical signal conduction layers is that the sensor with multiple electrical signal conduction layers forms a loop between its own electrodes, and makes a voltage difference between its own electrodes to obtain an electrical signal; The sensor of the single-electrode signal conducting layer obtains an electrical signal by forming a loop or a differential signal with the electrodes of another sensor or sensors measuring other sites. It should be noted that the pressure signal conducting layer in FIG. 7 may also include only one electrode (although not so shown). Similar to the bioelectrical signal conducting layer of the single electrode, the pressure signal conducting layer of the single electrode can also be de-differentiated from the potentials between the pressure conducting layers of one or more sensors to obtain a corresponding potential difference signal. For example such two single-electrode sensors may be located at the heart and the wrist, respectively, to measure the potential difference between the points to be measured at the heart and the wrist.

The sensors introduced in the above embodiments can adjust various parameters to achieve different ranges according to needs. However, the range and measurement accuracy are often contradictory, that is, no matter how the sensing principle, sensor parameters, and material selection are adjusted, the sensor's Range and sensitivity always tend to show a certain antagonistic nature, that is, when the sensor expands the range, it is often accompanied by a decrease in sensitivity within a certain range, and when the sensor increases its sensitivity within a certain range, it is often accompanied by the range. Decline. Based on this, the present invention further proposes a composite sensor with multiple sensing units, which is integrated by sensors with different sensitivities and ranges, so that the composite sensor can adapt to a wider range of ranges, and at the same time Maintain better measurement accuracy within the desired range.

Since different sensitivities and ranges may be required in various application scenarios, in order to solve this problem, the present invention further proposes a composite sensor structure, so that the range and sensitivity of the sensor can be achieved.

8 illustrates a schematic diagram of a composite sensor according to an embodiment of the present invention, which is a pressure signal conducting layer 1, a pressure sensitive layer 1, an insulating layer 1 (forming a pressure sensing layer 1) in order from top to bottom; a pressure signal Conductive layer 2 , pressure sensitive layer 2 , insulating layer 2 (forming pressure sensing layer 2 ); electrical signal conducting layer 1 . The pressure sensing principle and design parameters of the pressure signal sensing layer 1 and the pressure signal sensing layer 2 can be the same or different, for example, different pressure sensing principles can be used for the two (for example, the resistive pressure sensitive layer and the capacitive pressure sensitive layer), different materials, set to different thicknesses, etc. to match different ranges. Similarly, the configurations of the pressure sensing layer 1 and the pressure sensing layer 2, the insulating layer 1 and the insulating layer 2, and the bioelectrical signal conduction layer can also be arbitrarily set according to actual needs. It should be understood that the number, sequence, arrangement, material, sensing principle and other configuration methods illustrated here are only examples, and various configurations can be designed according to actual needs to meet application requirements. In addition, various spatial arrangements can also be used between the sensing layers, for example, overlapping up and down, crossing left and right, and different units are arranged at a certain space interval. As an example, FIG. 9 illustrates a schematic diagram of two arrangements, the upper diagram is a stacked structure, and the lower diagram is a staggered structure. After reading this specification by those skilled in the art, other arrangement structures are also obvious, so various arrangement structures that cannot be listed all should fall within the protection scope of the present invention.

In a multi-sensing layer configuration, for example, a sensor with a larger range and high sensitivity in some specific ranges can be realized.

For example, in the armband application that measures the EMG signal of the arm, when measuring the EMG signal of the arm and the pressure signal on the arm surface to analyze gesture movements (such as fisting, wrist bending, wrist extension, wrist internal rotation, wrist external rotation), These movements produce large changes in pressure on the arm surface, so a large range is required to detect such movements. At the same time, since the tiny and fine movements of the fingers will cause the pressure on the arm surface to change in some small ranges, it is necessary to improve the sensitivity in these ranges to improve the classification accuracy of gesture actions. For example, in such scenarios, a composite sensor with multiple sensing layers can be used, and the requirements of large range and high sensitivity can be met simultaneously through the appropriate configuration of different sensor layers.

Additionally, the required ranges and sensitivities may vary in various applications. For example, when measuring the pressure on the arm surface, the pressure variation range is larger, and when measuring the pressure variation on the face of a person, the variation range is smaller. A composite sensor with multiple sensing layers can be used, and the same sensor can measure both arm surface pressure and facial pressure or other applications through appropriate configuration of different sensor layers, thereby realizing a wide range of measurement devices. match.

In a further embodiment, the number of electrodes in both the pressure signal conducting layer and the bioelectric signal conducting layer is not limited to one or two, and more electrodes may be provided as required. For example, Figure 10 illustrates a sensor configuration in a multi-electrode form according to an embodiment of the present invention. In contrast to the previously described embodiment, the bioelectrical signaling layer includes a plurality of electrodes, and the potential difference between any two or more electrodes can be monitored as required, eg, electrodes 1-2, 1-3, and 1 can be monitored simultaneously The potential difference between -5, which can realize the measurement of bioelectrical signals at different spatial scales at the same time in the case of arranging only a single sensor. Similarly, the pressure signal conducting layer may also include more electrodes (although only two conducting layer electrodes are shown), so as to realize pressure signal measurement at different spatial scales. It should be noted that although the figure schematically shows a bioelectric signal conducting layer including 5 electrodes with a rectangular cross-section, the number, shape and arrangement of the electrodes can be arbitrarily set, for example, 9 electrodes with a space between them. Irregularly spaced hemispherical electrodes, etc. Similarly, the electrodes of the pressure signal conducting layer can also have any suitable configuration.

In a further embodiment, in order to make the pressure-sensitive layer more easily deformable, the pressure-sensitive layer can be provided with protrusions and/or depressions, for example, one or more arc-shaped protrusions or triangular protrusions and/or depressions, Or any arrangement and combination of protrusions and/or depressions with any other shape. 11 illustrates some examples of pressure sensitive layers with protrusions and/or depressions in accordance with embodiments of the present invention.

In some embodiments, the pressure-sensitive layer (eg, capacitive pressure-sensitive layer) includes at least two patterned electrodes, wherein the at least two patterned electrodes are separate electrodes that are electrically insulated from each other.

In some preferred embodiments, the pressure signal conducting layers can be designed as combs that mesh with each other but do not contact each other, which can achieve more sensitive detection, as shown in FIG. 12 . In some embodiments, when the pressure sensitive layer is subjected to pressure, its physical and/or chemical properties change, resulting in a change in the equivalent dielectric constant between two or more comb electrodes, thereby changing the relationship between the comb electrodes. capacitance between. In some embodiments, the pressure sensitive layer generates a potential difference when subjected to pressure, and this potential difference signal can propagate through the comb electrodes and be detected. In some embodiments, the resistance of the pressure sensitive layer changes when subjected to pressure, resulting in a change in the current between the electrodes to which the voltage is applied, thereby reflecting the change in pressure. Combined with the comb-shaped electrode, any other principle of pressure-sensitive layer can also be used to realize the sensing of pressure signals in the case of active or passive. Similarly, the comb sensor can also form a part of the above-mentioned composite sensor, and cooperate with the bioelectric signal conduction layer to realize the synchronous and isotopic detection of the pressure signal and the bioelectric signal.

FIG. 14 is an exploded schematic view of a capacitive sensor according to an embodiment of the present invention. The sensor is divided into a pressure sensing layer and a bioelectric sensing layer, wherein the pressure sensing layer may include a capacitive pressure sensing layer, an adhesive layer (such as double-sided tape), a first insulating layer, and a pressure signal conducting layer; The sensing layer includes a bioelectrical conductive layer and a second insulating layer; a third insulating layer is further arranged between the pressure sensing layer and the bioelectrical sensing layer. For example, the third insulating layer may be a polyethylene terephthalate (PET) film. Other materials may also be used to implement the third insulating layer.

The pressure signal conduction layer and the electromyography signal conduction layer are formed on PET by screen printing with conductive silver paste.

The pressure signal sensing layer can be realized based on the ionic supercapacitive method, wherein the capacitive pressure sensitive layer is an ionic polymer based on the ionic supercapacitive pressure sensing method (for example, made of polyvinyl alcohol (PVA) and one made of 1 -ethyl-3-methyl-imidazolium tricyanomethanide, (EMIM TCM) ionic liquid polymer) coating, which contains conductive ions and a polymer structure for providing space for ions to move. The capacitive pressure sensitive layer can form an electric double layer structure near the comb-shaped electrode. Due to the change of the contact area between the ionic polymer coating and the electrode under pressure, the capacitance formed between the electrodes changes, thereby forming a Measuring electrical signals (such as instantaneous current at constant voltage). On the interface between the electrode and the ionic polymer, ions and electrons form a tight charge layer due to electrostatic interaction, that is, an electric double layer. The tight electric double layer is similar to that of a plate capacitor. The distance is much smaller and thus has a larger capacity than ordinary capacitors.

The pressure signal conducting layer can be, for example, conductive silver paste printed on one side of the third insulating layer by screen printing, and the two or more electrodes of the pressure conducting layer are not in contact with each other but can be respectively connected with each other under the action of pressure. The ionic polymer coating contacts and transmits the electrical signal generated by the capacitive pressure-sensitive layer.

A cavity is formed between the capacitive pressure sensitive layer, the pressure signal conducting layer and the third insulating layer, and an opening can be left in the cavity, and the other positions are sealed with glue. Under the action of pressure, the volume of the cavity changes, and the contact area between each electrode and the ionic material layer changes, thereby changing the capacitance.

The bioelectric signal sensing layer can be realized based on the screen printing technology of conductive silver paste. The bioelectric signal conducting layer includes conductive silver paste printed on the other side of the third insulating layer, and is divided into two or more electrodes that are not in contact with each other. These electrodes can be in contact with the point to be measured and can conduct the skin. surface potential signal.

15 illustrates a schematic diagram of an electric double layer structure according to an embodiment of the present invention. Since the contact area between the pressure sensitive layer and the electrode of the pressure signal conducting layer changes under pressure, the capacitance formed between the electrodes changes, thereby forming a measurable electrical signal (such as an instantaneous current under a constant voltage). On the interface between the electrode of the pressure signal conduction layer and the pressure sensitive layer, ions and electrons form a tight charge layer due to static electricity, that is, an electric double layer. Due to the tight charge layer spacing, the distance between the charge layers of an ordinary capacitor is smaller than the distance between the charge layers of ordinary capacitors. Therefore, it has a larger capacity than ordinary capacitors.

Those skilled in the art should understand that the modules, methods, processes, steps and components herein are only examples, and they are not limited to be implemented in a specific physical component, but may be implemented in any same or different physical components . Unless explicitly stated, the above-mentioned modules/devices may be separate or integrated in a single physical component, and may be located locally or remotely. The above-mentioned modules/devices may be directly or indirectly coupled together or communicate through various means, including but not limited to mechanical connection, electrical connection, wireless communication, and mutual calls between software modules/processes/threads. It should be noted that the methods, steps, and processes described herein are not limited to the described order, but may be implemented in any suitable order, unless clearly defined in the relevant context. The drawings drawn herein are only exemplary representations, and the physical structures and arrangements thereof only represent examples of implementations, rather than limitations of the present invention. Those skilled in the art can modify the devices therein without departing from the scope of the present invention. , Modules and methods to adjust the position and exchange the order to better adapt to the specific installation site.

It should be noted that, in the foregoing description of the embodiments of the apparatus, the described logic, steps, processes, etc. are also applicable to the method embodiments of the present invention.

It can be known from the above disclosure that the present invention provides a sensor for detecting bioelectrical signals and pressure signals. In the embodiment of the present invention, a novel sensor is designed to realize the synchronous and isotopic detection function of the bioelectrical signal and the pressure signal. Compared with the prior art, it can achieve a lower cost and a simpler device structure under the condition of a relatively low cost and a simple device structure. , to achieve accurate identification and monitoring of the movement of living organisms.

Although the preferred embodiments of the embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once the basic inventive concepts of the present invention are known. Therefore, the appended claims are intended to be construed to include the preferred embodiment and all changes and modifications that fall within the true scope of this application.

Finally, it should also be noted that in this document, relational terms such as first and second are used only to distinguish one entity or operation from another, and do not necessarily require or imply these entities or that there is any such actual relationship or sequence between operations. Furthermore, the terms "comprising", "comprising" or any other variation thereof are meant to be non-exclusive, such that a process, method, article or device comprising a list of elements includes not only those elements, but may also include not expressly listed Other elements, or elements already in the prior art inherent in such a process, method, article or apparatus.

Claims (10)

1. A sensor for detecting bioelectrical signals and pressure signals, comprising: pressure sensitive layer; an electrical signal conducting layer comprising at least one electrode; Wherein, the pressure sensitive layer can sense pressure and convert the pressure into an electrical signal; the electrical signal conducting layer can collect the electrical signal and conduct the electrical signal through the electrode. 2 . The sensor according to claim 1 , wherein the pressure-sensitive layer and the electrical signal conducting layer are bonded together to form a sheet-like whole that can be closely attached to the surface of a living body. 3 . 3. The sensor according to claim 1 or 2, wherein the electrical signal conducting layer comprises a pressure signal conducting layer and a bioelectrical signal conducting layer, and the pressure sensitive layer is adhered to the pressure signal conducting layer to form a pressure conducting layer. A sensing layer, an insulating layer is arranged between the pressure sensing layer and the bioelectric signal conducting layer. 4. The sensor of any preceding claim, wherein the pressure sensitive layer is one of a resistive pressure sensitive layer, a capacitive pressure sensitive layer, a piezoelectric pressure sensitive layer, a triboelectric pressure sensitive layer, or variety. 5. The sensor of claim 4, wherein the capacitive pressure sensitive layer comprises at least one electrode, the pressure sensitive layer comprising a layer of ionic material for deforming by external pressure to affect the capacitance formed by the electrodes. 6. The sensor of claim 3, wherein the pressure-sensitive layer, the pressure-signaling layer, and the insulating layer enclose an enclosed or non-enclosed chamber. 7. The sensor of claim 6, wherein the pressure signal conducting layer and/or the pressure signal conducting layer is formed with one or more protrusions and/or depressions on the surface of the portion inside the chamber. 8. The sensor of claim 4, wherein the capacitive pressure sensitive layer comprises at least two patterned electrodes, wherein the at least two patterned electrodes are separate electrodes that are electrically insulated from each other. 9. The sensor of claim 8, wherein the patterned electrodes are comb electrodes, wherein the comb electrodes are arranged to intermesh but not contact each other. 10. The sensor of any one of claims 1-9, wherein the pressure sensitive layer and the electrical signal conducting layer are arranged in a stacked fashion.

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