CN104236591B

CN104236591B - A kind of sensing device based on triboelectricity technology and preparation and application thereof

Info

Publication number: CN104236591B
Application number: CN201410214880.2A
Authority: CN
Inventors: 韩昌报; 王中林; 李晓慧; 张弛
Original assignee: Beijing Institute of Nanoenergy and Nanosystems
Current assignee: Beijing Institute of Nanoenergy and Nanosystems
Priority date: 2014-05-20
Filing date: 2014-05-20
Publication date: 2016-11-16
Anticipated expiration: 2034-05-20
Also published as: CN104236591A

Abstract

The invention provides a kind of sensing device based on triboelectricity technology and preparation and application thereof, described sensing device utilizes triboelectricity technology to achieve without additional power source, the self-driven mode of operation that can be monitored at any time.The sensing device of the present invention includes two arrays, each array is made up of some independent unit, these unit intersect to form network structure by mutual insulating, are an independent sensing pixels point between the cross point that each two is adjacent, and the signal of telecommunication of each sensing unit individually exports.This network structure substantially increases the resolution of sensing device, decreases the wiring quantity that circuit connects, highly beneficial for large-scale industrial application.

Description

Sensing device based on friction power generation technology and preparation and use methods thereof

Technical Field

The invention relates to a sensing device and a preparation and use method thereof, in particular to a sensing device based on a friction power generation technology and a preparation and use method thereof.

Background

Tracking sensors are increasingly used in smart phones and body tracking systems, however current sensors are based on capacitive, or optical and magnetic effects. Generally, the power supply for these sensors is derived directly or indirectly from a battery. The situation that the standby is needed at any time and the signal monitoring is carried out at irregular time causes great power-off hidden trouble; and a large amount of maintenance work is needed in the aspects of battery power monitoring, battery replacement and the like when the system is applied in a large range; meanwhile, the traditional battery and the power supply system have larger volume and mass, so that the application of the sensor in certain fields is limited; furthermore, toxic chemicals contained in the battery present potential hazards to the environment and human body. Therefore, it is of great importance to develop a sensing technology capable of self-driving.

From 2012, a tribo-electrostatic effect-based triboelectric generator has developed rapidly, and provides a promising approach for converting mechanical energy into electric energy with its high-efficiency output, simple process and stable performance. Some friction power generating devices and devices that use friction power generation for sensing have been developed in succession. However, the sensors designed based on the existing friction generators have the defects of low resolution, complex positioning circuit and the like, and are not beneficial to practical application.

Disclosure of Invention

Aiming at the defects in the prior art, the invention designs a novel sensing device based on the friction power generation technology, so that the sensing device can work in a self-driven mode, not only can realize high resolution, but also can greatly simplify a detection circuit, and has very wide application prospect.

In order to achieve the above object, the present invention firstly provides a sensing device based on a friction power generation technology, which includes a first array, a second array and an electrical signal output end with one end grounded, wherein the first array is composed of n mutually independent first units, and the first units include a first electrode unit; the second array is composed of m mutually independent second units, and the second units comprise second electrode units; the first array and the second array form a net shape through insulating intersection at a certain angle, and the surfaces of the non-intersection positions of the first array and the second array form a sensing surface; the electric signal output end is respectively electrically connected with the n first electrode units and the m second electrode units, and is used for individually monitoring signals output by each electrode unit, wherein n and m are natural numbers;

preferably, each of said first cells crosses one second cell only once;

preferably, each of the first cells forms an intersection with m second cells;

preferably, the relative positions of the first unit and the second unit are the same at all the intersections;

preferably, the surfaces of the first and second arrays at the points of intersection are lower than the sensing surface at the points of non-intersection;

preferably, the device further comprises a substrate with holes, and the intersection points of the first unit and the second unit are sunk in the holes of the substrate;

preferably, at non-intersecting points, the surfaces of the first and second arrays lie in the same plane;

preferably, at any two adjacent intersections in the extending direction of the first unit and the second unit, the relative positions of the first unit and the second unit are opposite;

preferably, all of said first elements are parallel to each other, and/or all of said second elements are parallel to each other;

preferably, all of said first cells are arranged equidistantly, and/or all of said second cells are arranged equidistantly;

preferably, the shape and size of all the first electrode units are the same, and/or the shape and size of all the second electrode units are the same;

preferably, the first electrode unit and the second electrode unit are the same in shape and size;

preferably, the width of the first electrode unit is the same as the distance between two adjacent first electrode units;

preferably, the certain angle is a right angle;

preferably, at the intersection point, the first unit is separated from the second unit by a void, or by an insulating layer;

preferably, the first cell consists of only first electrode cells, and/or the second cell consists of only second electrode cells;

preferably, the liquid crystal display further comprises an isolation layer attached on the surfaces of the first array and the second array;

preferably, the isolation layer is an insulating material;

preferably, the outer surface of the first electrode unit and/or the outer surface of the second electrode unit are attached with a non-conductive friction layer;

preferably, the friction layer is an organic polymeric material;

preferably, the first and second units are of uniform material composition, shape and/or size.

The invention also provides a manufacturing method of the sensing device, which comprises the following steps:

(1) providing a substrate, wherein a plurality of holes are distributed on the substrate;

(2) insulating a first array comprising n mutually independent first units on the substrate such that each first unit passes through at least one of the holes;

(3) sinking the part of the first unit passing through the hole into the hole to form a recess;

(4) laying a second array comprising m independent second units on the substrate in an insulating manner, so that each second unit and at least one first unit intersect to form a net at the hole;

(5) sinking the part of the second unit passing through the intersection into the hole to form a recess, and keeping insulation between the first unit and the second unit at the recess;

(6) providing a plurality of electric signal output ends with one ends grounded, electrically connecting the electric signal output ends with the n first electrode units and the m second electrode units respectively, and monitoring the output signal of each electrode unit independently;

preferably, each hole on the substrate becomes an intersection of the first cell and the second cell;

preferably, the number of the holes is equal to or greater than n × m;

preferably, the apertures are distributed in a regular, determinant array;

preferably, the method further comprises the step (7) of removing the substrate;

preferably, the mutual insulation in step (5) is achieved by forming a gap between the two cells.

Preferably, step (3) is followed by step (3-1) of laying an insulating layer on the first unit in each of the holes.

(1) providing n + m wires with conductors inside and insulating material outside, and a plurality of electric signal output ends with one ends grounded;

(2) taking n threads as warps, taking m threads as wefts, and mutually crossing the warps and the wefts to form a net structure, wherein each warp is a first unit, and each weft is a second unit;

(3) the n warps and the m wefts are respectively and electrically connected with the electric signal output end through internal conductors so as to independently monitor the output signal of each unit;

preferably, the warp and weft are crossed to form a net shape by a weaving method;

preferably, in the extending direction of the first unit and the second unit, at any two adjacent intersections, the up-down relative positions of the first unit and the second unit are opposite;

preferably, the method further comprises the step (4) of removing the insulating material at the non-intersection points of the surfaces of the first unit and the second unit, so that the sensing surface is composed of the materials of the first electrode unit and the second electrode unit;

preferably, the insulating material is removed in step (4) by a mechanical polishing technique.

The invention also provides a using method of the sensing device, which comprises the steps of detecting the speed, the acceleration and the motion track of a single moving object by using the sensing device, wherein the single moving object slides on the sensing surface of the sensing device, and the change of the electric signal output by each unit along with the time is recorded;

preferably, the first and second arrays are reticulated by being orthogonal.

The sensing device based on the friction power generation technology has the most outstanding advantages of high resolution and simple output signal wiring. The two arrays form a network structure in a crossed mode, and insulation treatment is carried out at the crossed points, so that a sensing pixel point is formed on a small surface between every two crossed points, the process limitation that a small-size friction generator is difficult to manufacture is overcome, the resolution of the whole sensing device is greatly improved, and thousands of pixel points can be formed in each square centimeter. Meanwhile, only the electric signals of each unit in the array, not each pixel point, are monitored, so that the number of the electric signal monitoring points is reduced from n multiplied by m to n + m, and the wiring amount of output signals is greatly reduced. On the basis, the intersection of electric signals generated by the two arrays in the same time is skillfully utilized, so that the object positioning in a two-dimensional plane is realized; if the time dimension is added, the moving process of the object can be tracked.

In addition, the sensing device of the invention does not need external power supply, and as long as a moving object is contacted with the sensing surface, an electric signal is automatically output outwards, thus the sensing device is self-driven sensing. The method has particularly obvious advantages for tracking and monitoring a large-range random target.

The sensor of the invention has low price and simple manufacturing process, and is very suitable for large-scale industrial application.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent from the accompanying drawings. Like reference numerals refer to like parts throughout the drawings. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Additionally, although examples of parameters including particular values may be provided herein, the parameters need not be exactly equal to the corresponding values, but may be approximated to the corresponding values within acceptable error tolerances or design constraints. In addition, directional terms such as "upper", "lower", "front", "rear", "left", "right", and the like, referred to in the following embodiments, are directions only referring to the drawings. Accordingly, the directional terminology is used for purposes of illustration and is in no way limiting.

FIG. 1 is a schematic diagram of an exemplary configuration of a sensing device based on a friction power generation technology;

FIG. 2 is a schematic diagram of the electrical signal output principle of the sensing device of the present invention;

FIGS. 3(a) - (b) are schematic diagrams of two typical structures of a first unit and a second unit of a sensing device of the present invention;

FIG. 4 is a schematic view of another exemplary construction of the sensing device of the present invention;

FIGS. 5(a) - (b) are schematic diagrams of two exemplary configurations of the sensing device of the present invention;

FIGS. 6(a) - (d) are schematic diagrams of an exemplary method of making a sensing device according to the present invention;

FIG. 7 is an exploded view of the sensing device of the present invention monitoring the direction of movement of an object;

FIGS. 8(a) - (d) are schematic diagrams illustrating the operation of the sensing device of the present invention to monitor the movement of an object;

FIGS. 9(a) - (c) are a schematic structural diagram and an electric signal output spectrum of the sensing device of example 1;

FIGS. 10(a) - (c) are graphs of signals for tracking the movement of an object by the sensing device of the embodiment 1; and

fig. 11(a) - (c) are a schematic structural diagram and an electric signal output spectrum of the sensing device of example 2.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Next, the present invention is described in detail with reference to the schematic drawings, and when the embodiments of the present invention are described in detail, the schematic drawings are only examples for convenience of description, and should not limit the scope of the present invention.

Fig. 1 is a typical structure of a sensing device based on a friction power generation technology, which includes a first array, a second array and an electrical signal output terminal 30 with one end grounded, wherein the first array is composed of a plurality of mutually independent first units 10, and the first units 10 include a first electrode unit 101 (not shown); the second array is composed of a plurality of mutually independent second units 20, and the second units 20 comprise second electrode units 201 (not shown in the figure); the first array and the second array are crossed through insulation at a certain angle to form a net shape, the surface (namely the shaded part in the figure) at the non-crossed part of the first array and the second array forms a sensing surface, and the sensing surface between any two adjacent crossed points forms a sensing pixel point; the 2 multi-channel electrical signal output terminals 30 are electrically connected to each first electrode unit 101 and each second electrode unit, respectively, and individually monitor signals output by each electrode unit.

The working principle of the sensing device of the present invention is illustrated by taking as an example that the first electrode unit 101 and the second electrode unit 201 constitute a sensing surface, see in particular fig. 2, wherein x₁、x₂And x₃Representing different positions of 3 sensing pixels on the sensing device of the invention, A₁、A₂And A₃Is an electrical signal output 30 that is individually connected to each sensing pixel. When a moving object A to be monitored with a non-conductive surface and the sensing device of the invention are positioned on x₁When the surfaces of the sensing pixel points at the positions are contacted, surface charges with opposite electrical properties are formed on the contacted surfaces of the surface material A of the object to be monitored and the sensing surface material due to the fact that the triboelectric properties of the surface material of the object A are different from those of the sensing surface material; when in transitWhen the animal a moves away from the sensing pixel point, the first electrode unit 101 forming the sensing pixel point is kept neutral, and electrons are transferred through the electric signal output end 30 connected with the first electrode unit and having one end grounded, so that current output can be detected at the electric signal output end; when the moving object a with frictional charges on the surface continues to move and contact another sensing pixel, the electrode material corresponding to the pixel transfers electrons through the electrical signal output terminal 30 connected to the pixel and having one end grounded, so that the electrical signal can be detected at the electrical signal output terminal. Therefore, the sensor can sense the actions of entering, moving, leaving and the like of the moving object without an external power supply.

The triboelectric properties of the material in the invention refer to the electron gaining and losing ability of one material in the process of rubbing or contacting with other materials, namely one is positively charged and the other is negatively charged when two different materials are contacted or rubbed, which indicates that the two materials have different electron gaining abilities, namely the two materials have different triboelectric properties. For example, when the polymer nylon is in contact with the aluminum foil, the surface of the polymer nylon is positively charged, namely, the electron losing capability is strong, and when the polymer polytetrafluoroethylene is in contact with the aluminum foil, the surface of the polymer polytetrafluoroethylene is negatively charged, namely, the electron losing capability is strong.

In order to realize large-scale, high-sensitivity and high-resolution sensing, the present invention adopts a mesh structure formed by crossing two arrays, and the first unit 10 and the second unit 20 are the most basic components for providing a sensing surface and an electrode unit which are in contact with a moving object and output a sensing signal. The sensing surface is used for being in direct contact with a moving object to be monitored and forming surface charges through friction, the material of the sensing surface is the same as the friction surface of a common friction generator, and the sensing surface can be selected from insulating materials, semiconductor materials and conductor materials. Among these, the insulator may be selected from some commonly used organic polymer materials and natural materials, including: polytetrafluoroethylene, polydimethylsiloxane, polyimide, polydiphenyl propane carbonate, polyethylene terephthalate, aniline formaldehyde resin, polyoxymethylene, ethyl cellulose, polyamide, melamine formaldehyde, polyethylene glycol succinate, cellulose acetate, polyethylene adipate, polydiallyl phthalate, regenerated cellulose sponge, polyurethane elastomer, styrene propylene copolymer, styrene-acrylonitrile copolymer, styrene butadiene copolymer, polyamide nylon 11, polyamide nylon 66, wool and fabrics thereof, silk and fabrics thereof, paper, rayon, cotton and fabrics thereof, wood, hard rubber, polymethacrylate, polyvinyl alcohol, polyester, polyisobutylene, polyurethane elastomer, polyurethane flexible sponge, polyethylene terephthalate, polyvinyl butyral, polyethylene terephthalate, Phenolic resins, neoprene, butadiene propylene copolymers, natural rubber, polyacrylonitrile, poly (vinylidene chloride-co-acrylonitrile), poly (ethylene propylene carbonate), polystyrene, polymethyl methacrylate, polycarbonate, liquid crystal high molecular polymer, polychloroprene, polyacrylonitrile, acetate, poly (bisphenol carbonate), polychlorinated ether, polychlorotrifluoroethylene, polyvinylidene chloride, polyethylene, polypropylene, polyvinyl chloride and parylene, including parylene C, parylene N, parylene D, parylene HT or parylene AF 4.

Commonly used semiconductors include silicon, germanium; group III and V compounds such as gallium arsenide, gallium phosphide, and the like; group II and VI compounds such as cadmium sulfide, zinc sulfide, etc.; and solid solutions composed of group III-V compounds and group II-VI compounds, such as gallium aluminum arsenic, gallium arsenic phosphorus, and the like. In addition to the above-described crystalline semiconductor, an amorphous glass semiconductor, an organic semiconductor, and the like are available. Non-conductive oxides, semiconductor oxides and complex oxides also have triboelectric properties and can form surface charges during the triboelectric process and can therefore also be used as tribolayers according to the invention, for example oxides of manganese, chromium, iron, copper, including silicon oxide, manganese oxide, chromium oxide, iron oxide, copper oxide, zinc oxide, BiO₂And Y₂O₃。

Commonly used conductor materials include metallic and electrically conductive non-metallic materials, etc., such as: metals including gold, silver, platinum, aluminum, nickel, copper, titanium, chromium or selenium; an alloy formed of one or more selected from gold, silver, platinum, aluminum, nickel, copper, titanium, chromium, and selenium; conductive oxides such as indium tin oxide ITO; the organic conductor is generally a conductive polymer, and includes polypyrrole, polyphenylene sulfide, poly phthalocyanine compounds, polyaniline and/or polythiophene. For reasons of space and not intended to be exhaustive, and it is to be understood that these specific materials are not to be construed as limiting the scope of the invention since other similar materials may be readily selected by those skilled in the art based on the triboelectric properties of these materials.

The sensing surface can also be physically or chemically modified, so that a micro-structure array with micron or sub-micron magnitude is distributed on the sensing surface, the contact area between the sensing surface and an object to be monitored is increased, and the contact charge quantity is increased. The specific modification method comprises photoetching, chemical etching, plasma etching and the like. The purpose can also be achieved by means of the decoration or coating of nano materials, or the chemical modification is carried out on the sensing surface, so that the transfer quantity of the charges at the contact moment is further improved, and the contact charge density and the output power of the generator are improved.

In practical application, the material selection of the sensing surface is mainly considered to be matched with the material of an object to be monitored, and the difference of the triboelectric properties of the two surfaces which are in contact with each other is large as much as possible, for example, if the contact surface of the object to be monitored is a conductor material, the sensing surface can obtain better output performance by selecting an insulating material or a semiconductor material; if the contact surface of the object to be monitored is an insulating material, the sensing surface may take into account an insulating material, a semiconductor material or a conductor material having large differences in triboelectric properties, so that both are prone to generate surface contact charges during the rubbing process.

The triboelectric charges generated by the sensing surface need to pass through the electrode units to be output outwards, so the electrode units are necessary components in each unit. General conductive materials can be used to prepare the electrode unit, including metals and conductive non-metallic materials, such as: metals including gold, silver, platinum, aluminum, nickel, copper, titanium, chromium or selenium; an alloy formed of one or more selected from gold, silver, platinum, aluminum, nickel, copper, titanium, chromium, and selenium; conductive oxides such as indium tin oxide ITO; the organic conductor is generally a conductive polymer, including polypyrrole, polyphenylene sulfide, poly phthalocyanine compounds, polyaniline and/or polythiophene.

Since the sensing surface may also consist of an electrically conductive material, the surface of the electrode unit may also serve as the sensing surface in this case. This is the case as shown in figure 2. If the sensing surface is made of an insulating material or a semiconductor material, in order to ensure smooth output of surface charges, the sensing surface and the corresponding electrode unit should be closely attached. This attachment can be made in two ways: one is before the intersection to form the network, for example, each of the first and second units is composed of an electrode unit and a friction layer 40 attached to part or all of the surface of the electrode unit, and the final sensing surface is provided by the friction layer 40, as shown in fig. 3(a) - (b). Fig. 3(a) shows a case where the friction layer 40 is attached to the entire surface of the first electrode unit 101, and fig. 3(b) shows a case where the friction layer 40 is attached to the upper surface of the first electrode unit 101. The second unit 20 is similar to the first unit 10 and will not be described in detail herein. When two units as shown in fig. 3(a) - (b) are used to cross to form a mesh structure, the first unit 10 and the second unit 20 easily form an insulating structure at the crossing due to the presence of the friction layer 40. Alternatively, after the mesh structure is formed, a friction layer 40 is attached to the surface of the electrode unit to form the sensing surface, and the specific structure can be seen in fig. 4. In fig. 4, the first unit 101 and the second unit 201 are crossed through insulation to form a mesh structure, and the friction layer 40 is attached to the surface of the mesh structure.

In order to form the net structure, a plurality of independent first cells 10 and a plurality of independent second cells 20 are required, and n first cells 10 and m second cells 20 may be generally selected, where n and m are both natural numbers, and preferably both n and m are greater than 2. The composition, shape and size of each unit may be the same or different. Conventionally, the composition, shape and size of the units, and particularly the composition, shape and size of the electrode units, are the same, so that the electrical signals output when the object to be monitored enters each position are consistent. Sometimes to meet the important monitoring needs of an individual location, the first unit and the second unit of the location may be provided with different materials or dimensions, so that the object to be monitored can emit different signals for identification when passing through the location than other locations.

The relative positions of the first units 10 and/or the second units 20 can be set freely according to needs, and can be generally set in parallel, and the distance between two adjacent units can also be set equal, i.e. arranged equidistantly. To improve efficiency, the pitch between two adjacent cells may also be set to be equal to the cell width. Wherein the "cell width" is the width of the cell projected on the sensing surface perpendicular to the direction of extension.

The sensing device of the present invention is a mesh structure formed by the insulated intersection of the first cell 10 and the second cell 20. The relative position between the first unit 10 and the second unit 20 at the intersection is not generally limited, but for the sake of processing convenience, two configurations may be preferable (see fig. 5): one is that the relative positions of the first unit 10 and the second unit 20 are the same at all the intersections, see fig. 5(a), for example, the first unit 10 is on top, or the first unit 10 is on the bottom, which is particularly suitable for the case where the first array and the second array are laid separately, and in order to form the sensing pixels spaced apart from each other, it is preferable that the surfaces of the first array and the second array at the intersections are not higher than the sensing surface at the intersections, more preferably lower than the sensing surface, so that two adjacent sensing pixels are spaced apart by the intersections. In order to form a structure with a lower surface at the intersection, a substrate with holes can be used as an aid, see in particular the steps shown in fig. 6(a) - (d): first, a substrate 50 with a hole 60 is provided, a first unit 10 is laid on the substrate, the first unit 10 passing through the hole 60 is sunk into the hole 60 to form an embedded structure, then an insulating layer 70 is laid on the first unit 10 in the hole, and then a second unit 20 is laid according to a certain crossing angle, and the second unit 20 also forms an embedded structure passing through the hole 60, so that the first unit 10 and the second unit 20 form a cross with a lower surface at the hole 60. In order to ensure insulation between the two units, a certain gap may be left between the first unit 10 and the second unit 20 in the hole 60 as an insulating layer. Of course, if the first unit 10 and/or the second unit 20 further includes a non-conductive friction layer 40, the insulation relationship between the first unit 10 and the second unit 20 can be achieved by the separation of the friction layer 40 without having to leave a gap between the two or separately laying an insulation layer. It should be noted that although the holes 60 are shown in fig. 5 as being square, the shape of the holes 60 may be adjusted as needed in practical applications, i.e., the square shape is not a limitation of the present invention for the holes 60.

Another network structure is, see fig. 5 (b): at any two adjacent intersections in the direction in which the first unit 10 and the second unit 20 extend, the first unit 10 and the second unit 20 are oppositely positioned in the up-down direction. Such a structure is preferably produced by a weaving method, for example, in which the first array is used as warp and the second array is used as weft, and the warp and weft are cross-laminated to form a net structure having the above-mentioned characteristics. Although this construction can also be accomplished with a perforated base plate 50, it is more suitable for direct weaving. The first unit 10 and the second unit 20 can be woven by making the thin wires with the electrode units in the middle, and in order to form insulation at the intersection of the two units, a non-conductive friction layer 40 or an insulating isolation layer can be formed on the outer surface of each thin wire for isolation, and the isolation layer at the non-intersection point is removed after weaving. The sensor device thus obtained has the advantage of being easy to manufacture and of having a particularly high resolution.

The sensing device of the invention is preferably able to cross each first cell 10 with one second cell 20 only once, which ensures that only one intersection point can be determined by cross-analysis of the signals of both cells. More preferably, each first cell 10 crosses each second cell 20 once in order to increase the positioning efficiency of the sensor. The cross angle of the two units is not specially limited, can be selected according to actual needs, and can be set to be vertical cross in common use, namely, the cross angle is a right angle, so that an object to be monitored on the X-Y orthogonal coordinate system can be conveniently positioned.

To protect the sensing surface, a spacer layer, preferably an insulating material, may be applied to the surfaces of the first and second arrays, in a manner somewhat similar to the method of disposing the tribolayer 40 described above, but with the tribolayer 40 being selected primarily for its triboelectric properties and the spacer layer being selected primarily for its protective properties. The sensing device comprising the isolation layer is more suitable for objects to be monitored having a non-conductive surface, in which case the surface of the object to be monitored is easily charged directly by friction with the surrounding environment, without having to rely on contact with the sensing surface for the accumulation of surface charges, while the output of current is accomplished by electrostatic induction with the electrode elements in the sensing device.

One end of the electrical signal output end 30 is grounded, and the other end is electrically connected to each of the first electrode unit 101 and the second electrode unit 201, and individually monitors the output signal. For this purpose, a plurality of single-channel electrical signal outputs 30 may be used, for example, for the case where n first cells 10 and m second cells 20 form n × m cross-points, n + m single-channel electrical signal outputs 30 may be used, each cell having an electrical signal output for independent monitoring; it is also possible to use several multi-channel electrical signal outputs 30, each of which simultaneously monitors the output of a plurality of cells. Generally, the electrical signal output terminal 30 has a certain internal resistance, and an external resistor may be introduced therein for regulating the output signal, and the resistance of the resistor is not specifically limited, and 10M Ω is a possible choice as an example. The monitoring signal at the electrical signal output 30 may be a current and/or a voltage. A signal analysis system may also be included to analyze the monitored electrical signals. These are conventional in the art and will not be described in detail herein.

Although the sensor device of the present invention can be manufactured by various methods, the inventors have proposed two methods which are relatively simple and easy to be applied to large-scale industrial production, and are more suitable for manufacturing the sensor device of the present invention. One of them needs to have a substrate fit, and is more suitable for the case that the relative positions of the first unit 10 and the second unit 20 at all the intersection points are the same, specifically including the following steps (refer to fig. 6):

(1) providing a substrate 50, wherein a plurality of holes 60 are distributed on the substrate 50;

(2) laying a first array comprising n mutually independent first units 10 on a substrate 50 in an insulated manner, such that each first unit 10 passes through at least one hole 60;

(3) sinking the first cell 10 through a portion of the hole 60 into the hole to form a depression;

(4) laying an insulating layer 70 over the first cell 10 in each hole;

(5) laying a second array comprising m mutually independent second units 20 on the substrate 50 in an insulated manner so that each second unit 20 crosses at least one first unit at the hole 60 to form a net shape;

(6) sinking the part of the second unit 20 passing through the intersection into the hole to form a recess, and keeping insulation between the first unit 10 and the second unit 20 at the recess through an insulating layer;

(7) a plurality of electrical signal output terminals 30 with one end grounded are provided, and are electrically connected with the n first electrode units 101 and the m second electrode units 201 respectively, and the output signal of each electrode unit is monitored independently.

The substrate 50 in step (1) may be various substrate materials conventional in the art, such as organic glass, rubber plate, etc., preferably an insulating material, which may be rigid or have some flexibility and elasticity. The purpose of the substrate 50 is to provide the holes 60 to form a sunken structure for the two units at the intersection. The distribution of the holes 60 can be arranged according to the desired cross-network structure, preferably the holes 60 are arranged in a regular periodic distribution, in particular in a line-by-line array, on the substrate 50. The number of holes 60 should be matched to the number of intersections to be formed, and in order to improve the utilization of the holes 60, it is preferable that each hole on the substrate 50 be an intersection of the first cell 10 and the second cell 20. Meanwhile, considering that the substrate may also have a certain versatility, the number of holes 60 may be made equal to or greater than the number of intersections to be formed, for example, in the case of n first cells 10 and m second cells 20, the number of holes 60 is preferably equal to or greater than n × m, which leaves a certain space for the number and position adjustment of the intersections. The hole 60 only needs to have a certain depth, and is not necessarily limited to a through hole. The size of the hole 60 should match the size of the first unit 10 and the second unit 20 in order to be able to accommodate both units forming an embedded structure inside them. In the hole 60, the insulation between the two units can be realized by an insulating layer or an air space. If an insulating layer is arranged for isolation, a step (3-1) can be added after the step (3), an insulating layer 70 is laid on the first unit 10 in each hole, and then the step (4) is carried out.

Some sensing devices may be used without support from the substrate 50, and the method may further include the step (6) of removing the substrate 50, i.e., removing the substrate 50 after the substrate 50 is used to form and secure the structure.

The other method for manufacturing the sensing device provided by the invention is more suitable for the situation that the first unit 10 and the second unit 20 have opposite up-down relative positions at any two adjacent cross points. The method specifically comprises the following steps:

(3) and the n warps and the m wefts are respectively electrically connected with the electric signal output end through internal conductors so as to independently monitor the output signal of each unit.

Wherein the mesh structure formed in step (2) may be formed by crossing the warp and weft to form a mesh by a conventional mesh forming method in the art, preferably by weaving. For various woven structures, the preferred final resulting structure of the invention is: in the extending direction of the first unit 10 and the second unit 20, at any two adjacent intersections, the relative positions of the first unit 10 and the second unit 20 are opposite.

In the case where a conductive sensing surface is required, the method further comprises the step (4) of removing the insulating material at the non-intersection of the surfaces of the first unit 10 and the second unit 20, so that the sensing surface is composed of the materials of the first electrode unit 101 and the second electrode unit 201. In particular, the insulating material may be removed by mechanical polishing techniques.

The sensing device of the invention not only can detect the entering of the object to be monitored, but also can monitor the speed and the acceleration of a single moving object sliding on the surface of the object to be monitored, and track the motion track of the moving object. The method mainly comprises the steps of recording the electric signals output by each unit and analyzing the change of the electric signals with time. The specific principle is as follows (see fig. 7 and 8):

as can be seen from fig. 7, the motion in the two-dimensional plane can be decomposed into two motions in x and y one-dimensional directions, so the principle of monitoring the motion in one-dimensional direction by the sensing device of the present invention is described first. When the object to be monitored slides linearly from point a to point D, the trajectory can be decomposed into x-direction a → C motion and y-direction a → B motion, with the extending direction of the first array being the x-direction and the extending direction of the second array being the y-direction. The x direction is taken as an example to illustrate the principle of motion monitoring in one dimension.

Referring to FIG. 7, assume that the second array consists of several widthsThe second electrode units 201 are arranged in parallel at equal intervals (with a distance d), and each second electrode unit 201 corresponds to a fixed position x_nAnd independently outputs an electrical signal through an electrical signal output terminal 30, one terminal of which is grounded. Here, the intermediate process of the object to be monitored sliding on the sensing surface is taken as an example, when the surface of the object to be monitored already has a negative charge by contact with the sensing surface. The specific monitoring process can be divided into two cases:

in the first case, the width w of the object a to be monitored is equal to the electrode width (fig. 8 (a)). When the object A to be monitored contacts the first electrode unit x from the beginning₁When the electrode unit slides to the middle of the electrode unit, electrons flow to the ground from the electrode unit due to the electrostatic induction effect, and a reverse current pulse peak is formed; when the object A to be monitored continues to slide until just sliding out x₁At the edges of the electrode unit, also due to electrostatic induction, electrons will flow from earth to the electrodes, forming a positive current pulse peak. The spectrum of the electric signal output by the whole process is shown in fig. 8 (b).

It can be seen that the electrode units generating a pair of opposite pulse signals are the electrode units through which the object a to be monitored passes.

Object A to be monitored just contacts x₁The electrode units and the point in time of just complete departure are each t₁₁And t₂₂This will be recorded at the beginning and end of the current pulse peak. The object A to be monitored thus passes x₁The average velocity of the electrode unit is

v_{1} = \frac{x_{12} - x_{11}}{t_{12} - t_{11}} = \frac{l}{{Δt}_{1}} - - - (1)

Wherein x₁₁And x₁₂Is x₁The two outer sides of the electrode correspond to the position, where x₁₁-x₁₂Equal to the width l of the electrode unit. Similarly, when the object A to be monitored slides past the second electrode unit, the same pulse peak will be generated, the velocity v of which₂Is calculated by the formula

v_{2} = \frac{x_{22} - x_{21}}{t_{22} - t_{21}} = \frac{l}{{Δt}_{2}} - - - (2)

It can be calculated from this that the object A to be monitored passes x₁Electrode unit and x₂Acceleration during electrode unit of

a_{1 - 2} = \frac{v_{2} - v_{1}}{t_{2} - t_{1}} - - - (3)

In the second case, the width w of the object a to be monitored is not equal to the electrode width (fig. 8(c) shows the case where w is small). At this time, the object a to be monitored having a smaller size may travel only along one electrode unit in the x-axis direction without passing through the electrode unit in the y-axis direction, in which case there is a time interval between two pulse peaks formed (see fig. 8(d)), but the above formula is also applicable. Since an electrode unit is connected to the electrical signal output via only one line, it is also possible, according to the principle of triboelectric generators, to form intermittent pulse peaks, which also reflect the electrode unit on which the object is moving.

Through the above analysis, no matter the object a to be monitored moves along only one electrode unit, or passes through different electrode units at the same time, the sensing device of the present invention can monitor and analyze the position, speed, acceleration and other information. Thus, according to the decomposition relationship between the motion on the two-dimensional plane and the motion in the x and y directions, the motion parameters of the object a to be monitored from a to D directions in fig. 7 can be obtained from the two components along the x direction and along the y direction by the following combination operation:

\overset{&OverBar;}{v} = \sqrt{{\overset{- 2}{v}}_{x} - {\overset{- 2}{v}}_{y}} - - - (4)

v = \sqrt{v_{x}^{2} - v_{y}^{2}} - - - (5)

a = \sqrt{a_{x}^{2} - a_{y}^{2}} - - - (6)

wherein,representing the average velocity, v the instantaneous velocity, a the acceleration, and the subscripts x and y the x and y measured components, respectively.

In addition, according to the electric pulse signals of the two-dimensional imaging device on the x axis and the y axis, the included angle theta between the two-dimensional imaging device and the x axis can be obtained:

example 1

θ = arctg \frac{v_{y}}{v_{x}} = arctg \frac{a_{y}}{a_{x}} - - - (7)

Preparing 20cm multiplied by 20 cm-sized organic glass with holes as a substrate, laying 9 aluminum strips with the width of 6mm and the length of 20cm in parallel in the x direction of the surface of the substrate, wherein the distance d between every two adjacent aluminum strips is 14mm, the lower surface of each aluminum strip passes through 9 holes uniformly distributed on the substrate, and the parts passing through the holes are embedded into the holes through extrusion. Another 9 aluminum strips of the same size are prepared and laid on the surface of the substrate along the y direction in a similar manner, and cross the aluminum strips in the x direction at the holes, and an embedded structure is also made, but the embedding depth is controlled to ensure that the two aluminum strips are not in contact, thereby forming a mesh structure of 9 × 9 sensing pixels (see fig. 9 (a)). The end part of each aluminum strip is electrically connected with an electric signal output end with one end grounded, and a resistor of 10M omega is connected between the output end and the ground. A polytetrafluoroethylene sheet with the thickness of 13mm multiplied by 13mm is taken as an object to be monitored, the polytetrafluoroethylene sheet slides on the surface of a sensing device, the electric signal output of the sensing device is shown in fig. 9(b) and 9(c), the motion of the object to be monitored enables the sensing device to achieve the output of an open circuit voltage of nearly 70V and a short circuit current of 6 muA, and the output is enough to light an LED lamp so as to achieve the real-time visual monitoring of the motion of the object to be monitored. In addition, the average moving speed of the object was calculated to be 2.8cm/s according to the above equation (4).

When the object to be monitored slides from a to B point in an S-shaped path, fig. 10(a) and 10(B) show the time-varying spectrograms of the electric signals monitored at the electric signal output ends in the x direction and the y direction, and the x-y plane path curve synthesized from the signals of the two spectrograms (fig. 10 (c)). Based onThe given formula can calculate the real-time speed, the acceleration and the included angle between the motion direction and the x axis of the object to be monitored at the point B, which are 22.5cm/s and 0.2cm/s respectively²And 137. If the output signals of the x-axis and the y-axis are coupled according to time, an S-shaped motion track is obtained, and the position tracking function of the sensing device is shown.

Example 2

The enameled wires with the diameter of about 120 μm are woven into a net structure, the grid spacing is 250 μm, the number of electrodes in the dimension of 1cm in length is 41, and the electrode number in the dimension of 1cm in length is 1²The area of (a) has 41 x output ends and 41 y output ends, and the resolution of 41 × 41 is 1681 pixels, as shown in fig. 11(a), when an object with the diameter of 1.2mm slides on the device along the 'G' track, the single signal output of the x output end and the y output end is as shown in fig. 11(b), the current signal-to-noise ratio reaches 50, as shown in fig. 11(c), the change of the x-y output current peak signal along the time during the movement of the slide block is shown in fig. 11(b), the movement track can be clearly seen from the x-y coordinate axes, and the movement speed and the acceleration can be calculated by the relation of x-t and y-t.

The foregoing is merely a preferred embodiment of the invention and is not intended to limit the invention in any manner. Those skilled in the art can make numerous possible variations and modifications to the present teachings, or modify equivalent embodiments to equivalent variations, without departing from the scope of the present teachings, using the methods and techniques disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the scope of the protection of the technical solution of the present invention, unless the contents of the technical solution of the present invention are departed.

Claims

1. A sensing device based on a friction power generation technology comprises a first array, a second array and an electric signal output end with one end grounded, and is characterized in that the first array is composed of n mutually independent first units, and each first unit comprises a first electrode unit; the second array is composed of m mutually independent second units, and the second units comprise second electrode units; the first array and the second array form a net shape through insulating intersection at a certain angle, and the surfaces of the non-intersection positions of the first array and the second array form a sensing surface; the electric signal output end is electrically connected with the n first electrode units and the m second electrode units respectively, and is used for monitoring signals output by each electrode unit independently, wherein n and m are natural numbers.

2. The apparatus of claim 1, wherein each of the first cells crosses one second cell only once.

3. The apparatus of claim 2, wherein each of the first cells forms an intersection with m second cells.

4. The apparatus of claim 3, wherein the relative up and down positions of the first unit and the second unit are the same at all the intersections.

5. The apparatus of claim 4, wherein the surfaces of the first and second arrays at the intersection are lower than the sensing surface at the non-intersection.

6. The apparatus of claim 5, further comprising a substrate having apertures, wherein intersections of the first and second cells are trapped within the apertures of the substrate.

7. The apparatus of any one of claims 4-6, wherein the surfaces of the first and second arrays lie in the same plane at non-intersecting points.

8. The apparatus of claim 3, wherein at any two adjacent intersections in the extending direction of the first unit and the second unit, the relative positions of the first unit and the second unit are opposite.

9. The device according to any of claims 1-6 and 8, wherein all of said first cells are parallel to each other and/or all of said second cells are parallel to each other.

10. The apparatus of claim 9, wherein all of the first cells are arranged equidistantly and/or all of the second cells are arranged equidistantly.

11. The device according to any of claims 1-6 and 8, wherein all of the first electrode units are identical in shape and size and/or all of the second electrode units are identical in shape and size.

12. The apparatus of claim 11, wherein the first electrode unit and the second electrode unit are identical in shape and size.

13. The apparatus of claim 12, wherein the width of the first electrode unit is the same as the pitch of two adjacent first electrode units.

14. The apparatus of any of claims 1-6 and 8, wherein the certain angle is a right angle.

15. The device of any one of claims 1-6 and 8, wherein the first cell is separated from the second cell at the intersection by a void or by an insulating layer.

16. The device of any of claims 1-6 and 8, wherein the first cell consists of only a first electrode cell, and/or wherein the second cell consists of only a second electrode cell.

17. The apparatus of claim 16, further comprising a spacer layer attached over the surfaces of the first and second arrays.

18. The apparatus of claim 17, wherein the isolation layer is an insulating material.

19. The device according to any one of claims 1-6 and 8, wherein the outer surface of the first electrode unit, and/or the outer surface of the second electrode unit, is coated with a non-conductive friction layer.

20. The apparatus of claim 19, wherein the friction layer is an organic polymeric material.

21. The device of any of claims 1-6 and 8, wherein the first unit and the second unit are uniform in material composition, shape and/or size.

22. A method of making a sensing device according to any of claims 1-7, 9-21, comprising the steps of:

1) providing a substrate, wherein a plurality of holes are distributed on the substrate;

2) insulating a first array comprising n mutually independent first units on the substrate such that each first unit passes through at least one of the holes;

3) sinking the part of the first unit passing through the hole into the hole to form a recess;

4) laying a second array comprising m independent second units on the substrate in an insulating manner, so that each second unit and at least one first unit intersect to form a net at the hole;

5) sinking the part of the second unit passing through the intersection into the hole to form a recess, and keeping insulation between the first unit and the second unit at the recess;

6) and a plurality of electric signal output ends with one ends grounded are provided, are respectively electrically connected with the n first electrode units and the m second electrode units, and individually monitor the output signals of each electrode unit.

23. The method of claim 22, wherein each hole in the substrate becomes an intersection of the first cell and the second cell.

24. The method of claim 22, wherein the number of holes is equal to or greater than n x m.

25. The method of claim 24, wherein the apertures are distributed in a regular, determinant array.

26. The method of any one of claims 22-25, further comprising step (7) removing the substrate.

27. Method according to any of claims 22-25, characterized in that mutual insulation in step 5) is achieved by forming a gap between two units.

28. The method of any one of claims 22-25, further comprising, after step 3), step 3-1) laying an insulating layer over the first unit in each of the holes.

29. A method of making a sensing device according to any of claims 1-3, 8-21, comprising the steps of:

1) providing n + m wires with conductors inside and insulating material outside, and a plurality of electric signal output ends with one ends grounded;

2) taking n threads as warps, taking m threads as wefts, and mutually crossing the warps and the wefts to form a net structure, wherein each warp is a first unit, and each weft is a second unit;

3) and the n warps and the m wefts are respectively electrically connected with the electric signal output end through internal conductors so as to independently monitor the output signal of each unit.

30. The method of claim 29, wherein the warp and weft are crossed to form a mesh by weaving.

31. The method of claim 30, wherein the first unit and the second unit extend in opposite positions at any two adjacent intersections.

32. The method of claim 31, further comprising the step of 4) removing insulating material at non-intersections of the surfaces of the first and second cells such that the sensing surface is comprised of the materials of the first and second electrode cells.

33. The method of claim 32, wherein said insulating material is removed in step 4) by a mechanical polishing technique.