WO2023108424A1

WO2023108424A1 - Integrated sensor for monitoring underwater contact pressure and depth of water

Info

Publication number: WO2023108424A1
Application number: PCT/CN2021/137966
Authority: WO
Inventors: 程玙; 郭晨辉; 常煜
Original assignee: 中国科学院深圳先进技术研究院
Priority date: 2021-12-14
Filing date: 2021-12-14
Publication date: 2023-06-22

Abstract

An integrated sensor for monitoring an underwater contact pressure and the depth of water, which integrated sensor relates to pressure sensing. The sensor comprises double-sided adhesive (1), wherein an interdigital electrode (2) is fixedly connected to the bottom of the double-sided adhesive (1), an ionic material (4) is fixedly connected to the top of the interdigital electrode (2); the interdigital electrode (2) is prepared by a flexible circuit board, and a flexible substrate (3) is fixedly connected to the bottom of the interdigital electrode (2); the double-sided adhesive (1) is located between the interdigital electrode (2) and the ionic material (4); the interdigital electrode (2) is prepared from a conventional printing conductive material or by using a laser etching method; and the prepared flexible circuit board may be a single-sided, double-sided or multi-layer circuit. Water and an ionic material are both used as pressure sensing structures, an integrated sensing structure including a contact pressure information collection module and a water pressure information collection module is designed on the basis of an ionotronic sensing mechanism, and changes in a contact pressure signal and a water pressure signal can be monitored at the same time by means of a double-channel collection manner, such that comprehensive underwater pressure information is accurately fed back.

Description

An integrated sensor for underwater contact pressure and water depth monitoring

technical field

The invention relates to the field of pressure sensing, in particular to an integrated sensor for underwater contact pressure and water depth monitoring.

Background technique

The perception of underwater pressure information is of great value for ocean detection, underwater activities and other fields. The flexible pressure sensor can simulate the pressure perception function of human skin, and has the characteristics of high sensitivity, high flexibility and thinness. Good sticking effect.

Underwater pressure information perception also plays a prominent role in the movement of living bodies. Monitoring changes in pressure information generated by vital signs through wearable devices is of great significance for divers' health monitoring. Knowing the depth of divers is of great guiding significance for diving safety. The biomechanical analysis of aquatic animals can be of great value to the fields of life science research and bioengineering, and also has potential value for the monitoring of changes in the living environment of marine organisms, but it is technically difficult to measure these factors at the same time.

There are many challenges to pressure measurement in the underwater environment: For contact pressure information, hydrostatic pressure is difficult to ignore, and the output signal of the sensor will be affected by water pressure. Existing research has designed a symmetrical silicone rubber structure and filled it with liquid to offset it. The impact of static pressure, so as to directly measure the contact force. This water pressure balance solution obviously cannot meet the needs of underwater electronic skin, and will bring a burden on the volume. At the same time, it is difficult to output small signals under high water pressure. Now Some underwater pressure sensors are mainly used to monitor relatively large motion signals such as bending and twisting, and it is difficult to collect weak life signals. Because sensor pressure resolution is related to noise and sensitivity, high external water pressure will reduce sensor sensitivity and resolution. In addition, considering water depth changes, it is difficult for existing underwater pressure sensors to distinguish water pressure and contact pressure information. Water pressure information is often obtained by introducing reference calibration to obtain empirical curves to judge the depth of the sensor at the moment. It is difficult to collect water depth information and contact pressure information at the same time.

Contents of the invention

In order to overcome the above-mentioned defects of the prior art, the present invention provides an integrated sensor for underwater contact pressure and water depth monitoring. The technical problem to be solved by the present invention is: the difficulty in simultaneously collecting water depth information and contact pressure information.

An integrated sensor for underwater contact pressure and water depth monitoring, including double-sided adhesive tape, the bottom end of the double-sided adhesive tape is fixedly connected with an interdigital electrode, and the top end of the interdigital electrode is fixedly connected with an ionic material. The electrode is prepared by a flexible circuit board, the bottom end of the interdigital electrode is fixedly connected with a flexible substrate, and the double-sided adhesive is located between the interdigital electrode and the ion material.

In a preferred embodiment, the interdigitated electrodes are prepared by conventional printing conductive materials or laser etching methods, and the prepared flexible circuit board can be a single-sided, double-sided or multilayer circuit, and the flexible substrate can be Polyimide, polyethylene terephthalate, thermoplastic polyurethane, polydimethylsiloxane, etc. are used, and copper, silver, gold, platinum, and other inert metals can be used as electrode materials.

In a preferred embodiment, the thickness of the interdigital electrodes is: 1-1000 microns, further 10-500 microns, the line width of the interdigital strip electrodes is: 0.1-1000 microns, further 10-300 microns, the fork The distance between two adjacent electrodes of the finger electrode is: 0.1-1000 microns, further 10-300 microns.

In a preferred embodiment, the ionic material has a certain rough structure, and the ionic material has a cross-linked network structure and ion pathways, and the ionic material is composed of a light-cured ion gel material or a heat-cured silicone rubber material .

In a preferred embodiment, the network of the ionic material is doped with an ionic liquid having a polymerizable functional group structure, and the solvent of the ionic liquid of the ionic material is ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, dimethyl sulfoxide, dimethyl succinate, tributyl glutarate, the photoinitiators in the ionic materials include benzils and acetophenones, and the ionic liquids include vinylimidazole phosphates, vinyl imidazole sulfonimide salt, allyl imidazole sulfonimide salt, allyl imidazole phosphate, vinyl imidazole borate.

In a preferred embodiment, the content ratio of the main network material and the ionic liquid in the ionic material is: 1 part to 1000 parts of the main material of the ionic liquid; the solvent of the main network material is: 0.1 part to 10 parts, and the main material of the network is The initiator is: 0 part - 1 part.

In a preferred embodiment, the rough structure is prepared by a template method, wherein the template is obtained through a conventional photolithography process to obtain regular pyramids, hemispherical, columnar arrays, and other objects with irregular rough surface structures.

In a preferred embodiment, the material of the double-sided adhesive is selected from acrylic glue and polyurethane glue, the thickness of the double-sided adhesive is in the range of 10-200 microns, and the double-sided adhesive forms a closed seal in the water pressure monitoring module area. structure, when the external water pressure changes, since the water pressure monitoring module is a closed structure, the ionic material will be deformed under the influence of the pressure, and will contact the interdigital electrode structure, resulting in interface capacitance.

In a preferred embodiment, the double-sided adhesive forms an open structure in the area of the contact pressure monitoring module, leaving a liquid channel. When immersed in water, the surrounding liquid will fill the gap between the electrode and the ionic material, and the liquid environment is a belt The liquid with ions, the liquid with ions is: sodium chloride solution, the liquid with ions can also be: potassium chloride solution, calcium chloride solution, magnesium sulfate solution and the above-mentioned mixed systems, and natural Common seawater systems, freshwater systems, lake systems, etc.

In a preferred embodiment, the dual-channel structure of the integrated sensor can be connected to the inductance-capacitance-resistance detection system to detect the change of the capacitance signal when the pressure changes; , connected to the detection system of the data acquisition card, the capacitance change corresponding to the pressure change is converted into the change of the output voltage through the operational amplifier circuit, and the signal of a certain channel is collected separately or the signal of two channels is collected simultaneously.

Technical effect and advantage of the present invention:

The present invention uses water and an ionic material as the pressure sensing structure at the same time, and based on the ionization sensing mechanism, designs an integrated sensing structure including dual modules of contact pressure information acquisition and water pressure information acquisition. , can simultaneously monitor the contact pressure signal and water pressure signal changes, so as to accurately feed back the comprehensive information of underwater pressure;

Description of drawings

Fig. 1 is a schematic structural diagram of the sensor of the present invention.

Fig. 2 is several examples of sensor electrode design of the present invention

Fig. 3 is a schematic diagram of the working principle of the water pressure and contact pressure module of the present invention.

Fig. 4 is the pressure response curve of the water pressure and contact pressure module of the present invention.

Reference signs are: 1, double-sided adhesive tape; 2, interdigitated electrodes; 3, flexible base material; 4, ionic material; a, excitation signal end; b, contact pressure signal; c, water pressure signal.

Detailed ways

The technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. In addition, the forms of the structures described in the following embodiments are only examples. The underwater contact involved in the present invention The pressure and water depth monitoring integrated sensor is not limited to the structures described in the following embodiments, and all other embodiments obtained by those of ordinary skill in the art without creative work belong to the protection of the present invention scope.

Embodiment 1: Referring to Figures 1-4, the present invention provides an integrated sensor for underwater contact pressure and water depth monitoring, including a double-sided adhesive 1, characterized in that the bottom of the double-sided adhesive 1 is fixedly connected with an interdigital electrode 2. The top of the interdigital electrode 2 is fixedly connected with an ionic material 4. The interdigital electrode 2 is made of a flexible circuit board. The bottom of the interdigital electrode 2 is fixedly connected with a flexible substrate 3. The double-sided adhesive tape 1 is located on the interdigital electrode 2. In the middle with ionic material 4.

Further, the interdigital electrodes 2 are prepared by conventional printed conductive materials or laser etching methods, and the prepared flexible circuit board can be a single-sided, double-sided or multi-layer circuit, and the flexible substrate 3 can be made of polyimide, poly Ethylene terephthalate, the electrode material can be gold, platinum, and copper, silver and other inert metals.

Further, the thickness of the interdigitated electrode 2 is: 1-1000 microns, further 10-500 microns, the line width of the interdigitated strip electrodes is: 0.1-1000 microns, further 10-300 microns, the adjacent interdigitated strip electrodes The distance between the two electrodes is: 0.1-1000 microns, further 10-300 microns.

Further, the ionic material 4 has a certain rough structure, and the ionic material 4 has a cross-linked network structure and ion pathways. The ionic material 4 is composed of a light-cured ion gel material or a heat-cured silicone rubber material. The main network structure includes acrylates , Polyether acrylates, epoxy acrylates, polyurethane acrylates, methyl vinyl silicone rubber, methyl phenyl vinyl silicone rubber, fluorosilicone rubber, nitrile silicone rubber.

Further, the network of the ionic material 4 is doped with an ionic liquid having a polymerizable functional group structure, including but not limited to vinylimidazole sulfonimide salts, vinylimidazole phosphates, vinylimidazole borates, alkenyl Propyl imidazole sulfonylimide salt, allyl imidazole phosphate, vinyl imidazole borate; ionic material 4 ionic liquid solvents are ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ionic material 4 The solvent of the ionic liquid can also be: dimethyl sulfoxide, dimethyl succinate, tributyl glutarate; the photoinitiator in the ionic material 4 includes benzils, acetophenones, and the ionic material 4 Photoinitiators also include: α-hydroxy ketones, acyl phosphine oxides, ionic liquids are vinylimidazole phosphate, vinylimidazole sulfonimide, allyl imidazole sulfonimide, alkene Propyl imidazole phosphate, vinyl imidazole borate.

Further, the content ratio of the network main material and the ionic liquid in the ionic material 4 is: 1 part-1000 parts of the main material of the ionic liquid; 0.1 part-10 parts of the solvent of the main network material, and 0 part of the initiator of the main network material -1 part, the concept of capacitance per unit area is introduced here to represent the ionic properties of the material. The capacitance per unit area of the ionic material prepared in this study is 0.0001-0.01 of that of water.

Further, the rough structure is prepared by the template method, in which the template is obtained by the traditional photolithography process in the regular pyramid shape, hemispherical, columnar array, and other objects with irregular rough surface structure, and the precursor of the ionic material is solidified in the template , the specific surface topology can be obtained.

Further, the material of the double-sided adhesive 1 is selected from acrylic glue and polyurethane glue. The thickness of the double-sided adhesive 1 is in the range of 10-200 microns. The double-sided adhesive 1 forms a closed structure in the area of the water pressure monitoring module. When the external water pressure changes , because the water pressure monitoring module is a closed structure, the ionic material will deform under the influence of pressure, contact the interdigital electrode structure, and generate interface capacitance, the water pressure increases, the capacitance becomes larger, and its capacitance value is related to the capacitance per unit area of the ionic material and the contact area positive correlation, which facilitates detection.

Furthermore, the double-sided adhesive 1 forms an open structure in the area of the contact pressure monitoring module, leaving a liquid channel. When immersed in water, the surrounding liquid will fill the gap between the electrode and the ionic material. The liquid environment is a liquid with ions. The liquid with ions is: sodium chloride solution. During the liquid filling process, an electric double layer structure is formed at the interface between the fluid layer and the electrode, and the entire sensor structure is placed under water. When pressure is applied, the ionic material deforms and presses down. Contact the electrode surface, discharge the liquid at the contact point, reduce the water-electrode interface capacitance, but increase the ionic material-electrode interface capacitance, and its capacitance value is jointly affected by the unit area capacitance of the ionic material and water. Area capacitance, water is much higher than that of ionic materials, and finally manifested as a decrease in capacitance value under pressure.

Furthermore, the dual-channel structure of the integrated sensor leads out by connecting two single-point interdigitated electrodes with the same excitation signal, and connects the data acquisition card detection system. The capacitance change corresponding to the pressure change can be converted into a change in the output voltage through the operational amplifier circuit. The signal of one channel is collected separately or the signal of two channels is collected at the same time. The two ends of the interdigitated electrodes are connected to the inductance-capacitance-resistance detection system, and the pressure at a certain moment can be deduced through the capacitance-pressure diagram.

Embodiment two:

Preparation of ionic materials: Prepare an array with a hemispherical structure by photolithography. The diameter of the hemisphere is 50 microns, and the point-to-point distance is 100 microns. The silicone rubber precursor is coated on the photoresist plate, heated in an oven at 80 degrees for 2 hours, and after taking it out The cured silicone rubber A is peeled off from the photoresist plate to obtain a concave array structure, the polyurethane acrylate prepolymer is dissolved in tributyl glutarate solvent, and the ionic liquid 1-vinyl-3-butylimidazole bis Trifluoromethanesulfonimide salt, add photoinitiator 1173, wherein the mass ratio of polyurethane, ionic liquid, solvent, and 1173 is: 1:0.02:2:0.05, stir evenly and pour into the concave array structure, UV light curing for 2min , the film was peeled off to obtain the ion gel material with a rough structure.

Electrode preparation: The double-channel interdigitated electrode structure is prepared on the PET gold-plated film by laser etching process, in which the line width and line spacing of the interdigitated electrodes are both 200 microns, and the overall size of the electrode is 10mm*10mm. The electrode size of the contact pressure module It is 7mm*10mm, and the electrode size of the hydraulic module is 2mm*10mm.

Sensor preparation: the double-sided adhesive is cut by laser to obtain a specific structure, the ion gel is cut into a 10mm*10mm square, and the rough surface faces the interdigital electrode, bonded to the surface of the electrode through the double-sided adhesive, and placed in 0.5% chlorine In the sodium chloride solution, the liquid fills the gap between the electrode and the ion gel in the contact pressure module, and the water pressure module is a closed structure, and finally an integrated underwater sensor is obtained.

The manufactured sensor uses the inductance-capacitance-resistance detection system to deduce the pressure at a certain moment more accurately, and uses the data acquisition card detection system to measure the change of dual-channel capacitance under different water pressures and different contact forces underwater more quickly.

The last few points should be explained: First, in the description of this application, it should be explained that, unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, which can be mechanical connection Or electrical connection, it can also be the internal communication of two components, it can be directly connected, "up", "down", "left", "right", etc. are only used to indicate the relative positional relationship, when the absolute position of the object being described Change, the relative positional relationship may change;

Secondly: in the drawings of the disclosed embodiments of the present invention, only the structures related to the disclosed embodiments are involved, other structures can refer to the usual design, and the same embodiment and different embodiments of the present invention can be combined with each other if there is no conflict;

Finally: the above is only a preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention within the scope of protection.

Claims

An integrated sensor for underwater contact pressure and water depth monitoring, comprising a double-sided adhesive (1), characterized in that: the bottom end of the double-sided adhesive (1) is fixedly connected with an interdigital electrode (2), and the interdigital The top of the electrode (2) is fixedly connected with an ionic material (4), the interdigital electrode (2) is prepared from a flexible circuit board, and the bottom end of the interdigital electrode (2) is fixedly connected with a flexible substrate (3) , the double-sided adhesive tape (1) is located between the interdigital electrode (2) and the ion material (4).
An integrated sensor for underwater contact pressure and water depth monitoring according to claim 1, characterized in that: the interdigital electrodes (2) are prepared by conventional printed conductive materials or laser etching methods, and the prepared flexible circuit The board can be a single-sided, double-sided or multilayer circuit, and the flexible substrate (3) can use polyimide, polyethylene terephthalate, thermoplastic polyurethane, polydimethylsiloxane, etc., The electrode material can be copper, silver, and gold, platinum, and other inert metals.
An integrated sensor for underwater contact pressure and water depth monitoring according to claim 1, characterized in that: the thickness of the interdigital electrode (2) is: 1-1000 microns, further 10-500 microns, the interdigital strips The line width of the electrodes is: 0.1-1000 microns, further 10-300 microns, and the distance between two adjacent electrodes of the interdigitated strip electrodes is: 0.1-1000 microns, further 10-300 microns.
An integrated sensor for underwater contact pressure and water depth monitoring according to claim 1, characterized in that: the ionic material (4) has a certain rough structure, and the ionic material (4) has a cross-linked network structure and For ion pathways, the ion material (4) is composed of ion gel material or silicon rubber material.
The integrated sensor for underwater contact pressure and water depth monitoring according to claim 4, characterized in that: the network of the ionic material (4) is doped with an ionic liquid having a polymerizable functional group structure, and the ionic material ( 4) The solvent of the ionic liquid is ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, dimethyl sulfoxide, dimethyl succinate, tributyl glutarate, and the initiator in the ionic material (4) Including azos, benzils, acetophenones, α-hydroxy ketones, acylphosphine oxides, the ionic liquids are vinylimidazole phosphates, vinylimidazole sulfonimide salts, olefin Propyl imidazole sulfonylimide salt, allyl imidazole phosphate, vinyl imidazole borate.
An integrated sensor for underwater contact pressure and water depth monitoring according to claim 4, characterized in that: in the ionic material (4), the content ratio of the main network material and the ionic liquid is: 1 part of the main material of the ionic liquid -1000 parts; network main material solvent: 0.1-10 parts, network main material initiator: 0-1 part.
An integrated sensor for underwater contact pressure and water depth monitoring according to claim 4, characterized in that: the rough structure is prepared by a template method, wherein the template is a regular pyramid, hemispherical, Cylindrical arrays, and other objects with irregular rough surface structures.
An integrated sensor for underwater contact pressure and water depth monitoring according to claim 1, characterized in that: the material of the double-sided adhesive (1) is selected from acrylic adhesive and polyurethane adhesive, and the double-sided adhesive (1) The thickness range is 10-200 microns. The double-sided adhesive (1) forms a closed structure in the area of the water pressure monitoring module. When the external water pressure changes, because the water pressure monitoring module belongs to the closed structure, ionic materials will be generated under the influence of pressure. Deformation, contact with the interdigitated electrode structure, resulting in interfacial capacitance.
An integrated sensor for underwater contact pressure and water depth monitoring according to claim 1, characterized in that: the double-sided adhesive (1) forms an open structure in the area of the contact pressure monitoring module, leaving a liquid channel, when immersed in water , the surrounding liquid will fill the gap between the electrode and the ionic material. The liquid environment is a liquid with ions, which can be changed depending on the application scene, including but not limited to NaCl solution, KCl solution, CaCl 2 solution, MgSO4 solution and The above-mentioned mixed systems, as well as common seawater systems, freshwater systems, lake systems, etc. in nature. .
An integrated sensor for underwater contact pressure and water depth monitoring according to claim 1, characterized in that: the dual-channel structure of the integrated sensor can be connected to an inductance-capacitance-resistance detection system or a data acquisition card detection system, and the pressure changes The corresponding capacitance change can be converted into the change of the output voltage through the operational amplifier circuit, and the signal of one channel is collected separately or the signals of two channels are collected simultaneously.