38results about How to "Significant change in resistance" patented technology

The invention provides a flexible piezoresistive touch sensor array and a preparation method thereof. The sensor array comprises N*N separated piezoresistive layers and a coplanar electrode layer. The piezoresistive layers are arranged on the coplanar electrode layer. Each piezoresistive layer comprises an upper finger pressing layer, a middle sensitive layer and a bottom sensitive layer, wherein the three layers are each provided with a micro pyramid; the coplanar electrode layer comprises a polymer electrode substrate and N*N gold electrode pairs located on the polymer electrode substrate. The piezoresistive layers adopt polymer films with the micro pyramid, and due to the three-layer structure, the sensitivity of the sensor at the low-voltage region can be greatly improved. In addition, in order to overcome the defect that a traditional touch sensor is large in crosstalk due to a sandwiched structure, the coplanar electrode layer is adopted, all electrodes are located on the same plane, each piezoresistive layer is attached to the corresponding electrode pair, the piezoresistive units are completely separated, and the sensitivity and anti-interference capacity of the sensor are effectively improved.

The invention discloses a conductive hydrogel composite material which is sensitive to humidity level fluctuation, a device and a preparation method, which relates to a smart material and a device and a preparation method, wherein, the conductive hydrogel composite material and the preparation method thereof comprises four steps of dispersion of conductive filling materials, in situ polymerization, casting to be shaped and electrode trimming; the conductive hydrogel composite material and the device comprise a hydrogel which is sensitive to humidity level fluctuation, the conductive filling materials and an additive. In the process of responding to the environmental moisture change, the obtained conductive hydrogel composite material and the device can make a sensitive response to the external moisture change. The conductive hydrogel composite material and the device can obtain practical applications in the fields of biomedicine, fluid control, diffusion and permeation, intelligent machinery and the like.

A first and a second tunnel junctions (2 and 3) which have a common electrode composed of a nonmagnetic conductor (4) and each of which has a counterelectrode composed of a ferromagnet (6, 8) are disposed spaced apart from each other by a distance that is shorter than a spin diffusion length of the nonmagnetic conductor (4) wherein the first tunnel junction (2) acts to inject spins from the ferromagnet (6) into the nonmagnetic conductor (4) and the second tunnel junction (3) serves to detect, between the ferromagnetic metal (8) and the nonmagnetic conductor (4), a voltage that accompanies spin injection of the first tunnel junction (2) and wherein the nonmagnetic conductor (4) is a nonmagnetic conductor, such as a semiconductor or a semimetal, that is lower in carrier density than a metal. The common electrode alternatively may be composed of a superconductor (4′). A spin injection device thus provided can exhibit a large signal voltage with low current and under low magnetic field and can be miniaturized in device size. Magnetic apparatuses utilizing such a spin injection device are also provided.

The invention provides a flexible pulse sensor and a manufacturing method thereof. The flexible pulse sensor comprises a flexible base, carbon nano tube-graphene composite film of which part is embedded into the flexible base, and electrodes, wherein the electrodes are arranged at two ends of the carbon nano tube-graphene composite film; the thickness of the flexible base is 0.8-1.2mm; the light transmittance of the initial carbon nano tube is 85-95%, and the light transmittance of the carbon nano tube-graphene composite film obtained through chemical vapor deposition is 80-92%. According to the flexible pulse sensor and the manufacturing method thereof, the carbon nano tube, the graphene and the flexible base synergize with one another so that the flexible pulse sensor can not only have the advantages of the graphene and the carbon nano tube sensor but also avoid the disadvantages of the graphene and the carbon nano tube sensor, the mechanical stability of a strain sensor is strengthened, the pulse sensor does not lose efficacy within at least 10% of strain ranges, the pulse sensor can effectively catch pulse signals, and the detecting effect is reached.

The invention discloses a synaptic transistor based on a two-dimensional semiconductor material and a preparation method of the synaptic transistor. The synaptic transistor comprises an insulating substrate, and a channel, a source electrode, a drain electrode and a gate electrode which are arranged on the substrate, wherein the channel is a two-dimensional semiconductor material; the source electrode and the drain electrode are arranged at the two ends of the channel respectively and form an ohmic contact with the channel material; the gate electrode and an electrical interconnection system formed by the channel, the source electrode and the drain electrode are kept in electronic insulation; an organic electrolyte covers a channel region and most of the gate electrode and comprises an organic carrier capable of being electrically insulated and ions capable of being migrated, and effective ion control of the gate to the channel material is formed. According to the synaptic transistor based on the two-dimensional semiconductor material and the preparation method of the synaptic transistor, an ion attachment-intercalation mechanism is utilized, and the characteristics of large surface area and adjustable resistance value of the two-dimensional material are combined, so that the device shows long-term and short-term synaptic plasticity, and the two characteristics can change witheach other along with the change of a gate signal. Meanwhile, the device has good linearity and ultralow operational power consumption, and the implementation and large-scale integration application of a high-precision neuromorphic device are facilitated.

The invention discloses self-healing conductive hydrogel and a preparation method and application thereof. The hydrogel is prepared from, by weight, 76-107 parts of hydrophobic modified polyacrylamideserving as a hydrogel matrix, 0.2-1 part of small molecular surface modified silver nanowires and 4-14 parts of glucan through one-step in-situ synthesis. The small molecular surface modified silvernanowire is a small molecular organic matter N, N-bisacryloyl cystamine surface modified silver nanowire. The two ends of the self-healing conductive hydrogel are connected with wires and packaged toobtain the self-healing conductive hydrogel sensor. According to the preparation method, the conductive, high-strength and self-healing hydrogel can be prepared simply and efficiently, self-healing can be realized after fracture, and the conductivity and the sensibility can be recovered.

A shear strain type pressure sensor comprises a shell. A magnetic field generating device in the shell comprises two magnetic poles which are opposite in magnetism and correspond to each other oppositely. A shear plate is arranged in the gap between the two magnetic poles, a rubber sheet is fixed on one side of the shear plate and in full contact with the end face of the first magnetic pole in the two magnetic poles, and a first electrode is fixed on the other side of the shear plate and fixedly provided with a magnetorheological elastomer. A second electrode is fixed on the other side of the magnetorheological elastomer, the second electrode is fixedly connected with the end face of the second magnetic pole in the two magnetic poles, the first electrode and the second electrode are electrically connected with a signal conditioning module, one end of the shear plate upwards extends to penetrate through an S-shaped force measuring piece and then extends out of the upper end face of the shell, a supporting plate used for supporting the S-shaped force measuring piece is fixed in the shell, a stop piece is arranged on the shear plate, and the lower end face of the stop piece is in contact with the upper end face of the S-shaped force measuring piece. The shear strain type pressure sensor is high in resolution, high in sensitivity, and large in force testing range.

The invention relates to a color-variable flexible electronic skin and a preparation method thereof. The preparation method comprises the steps of: (1) preparing a PDMS substrate; (2) preparing a salient point microstructure PDMS; (3) preparing a conductive graphite type thin film salient point microstructure PDMS substrate; (4) preparing a TCO / PDMS counter electrode substrate; (5) placing the TCO / PDMS counter electrode substrate on the conductive graphite type thin film salient point microstructure PDMS substrate to form a resistive pressure sensor; (6) preparing solid / colloidal electrolyte;(7) preparing a flexible ECD; and (8) integrating a flexible ECD with the resistive pressure sensor to form a power amplifier circuit. The color-variable flexible electronic skin is a chameleon simulating color-variable skin, has relatively good performance to pass color variation, and is capable of feeling external temperature and surrounding environment change and giving alarm or prompt. The preparation method is simple, efficient and low in cost, is capable of realizing reel-to-reel industrial production and can be used for monitoring, for environment, of natural people, artificial intelligence and robots.

The invention relates to a high sensitivity flexible pressure sensor and a preparation method thereof; the sensor comprises a conductive silica gel layer and a flexible substrate arranged below the conductive silica gel layer; the flexible substrate is a silica gel layer and in a hollow structure, and arranged in a shape of a Chinese character chuan or jing, or in a rhombus hollow structure; a bonding layer is arranged below the flexible substrate, and made of a hot melt adhesive. The flexible substrate of the flexible pressure sensor is in a hollow structure; the conductive silica gel layer can form bigger deformations when receiving external pressures, and the resistance change is more obvious, so the sensor is more sensitive; different hollow structures can bring about different sensitivities and piezoelectric relations; the hollow structure can be changed so as to adapt to pressure sensors of different occasions; the hot melt adhesive bonding layer can firmly glue the flexible pressure sensor on clothes through hot pressing; the flexible pressure sensor is wearable, hard to drop, and durable.

The invention discloses an overvoltage warning device and method based on a pressure sensor and an electrochromic device. The overvoltage warning device comprises a control circuit, a signal input line, a trigger pressure adjustment knob, a voltage display area, a delay adjustment knob, a delay trigger switch, an output line and an electrochromic device, wherein the control circuit is provided with a pressure sensor, a first slide rheostat, a voltmeter, an NPN triode, a second slide rheostat and a switch; the signal input line is extracted from two ends of the pressure sensor; the trigger pressure adjustment knob is connected with the first slide rheostat; the voltage display area is connected with the voltmeter; the delay adjustment knob is connected with the second slide rheostat; the delay trigger switch is connected with the switch; the output line is extracted from an output end; and the electrochromic device is connected with two ends of the output line. When the overvoltage warning device is triggered by pressure, the output voltage is immediately reversed, and the electrochromic device is enabled to change in color; and when the pressure is below a trigger value, the outputvoltage is enabled to be reversed again, and the electrochromic device is enabled to return back to be original color. The overvoltage warning device is simpler and more stable in control circuit, less in consumed electric energy, safer and more environment-friendly and has a good warning effect.

The invention discloses a graphene array-based flexible pressure sensor and a preparation method thereof. Two flexible substrates are distributed in parallel, and an upper graphene array and a lower graphene array are fixedly arranged on one flexible substrate and located between the two flexible substrates; the graphene pressure sensing units are distributed in an array mode, and the graphene pressure sensing units in the upper-layer graphene array and the graphene pressure sensing units in the lower-layer graphene array are aligned and tightly attached. When pressure acts on the graphene array, the graphene conductive paths are increased, a resistance value is reduced, the demodulation circuit can measure and calculate the resistance value change of each graphene pressure sensing unit, and the pressure change condition is accurately obtained through a pressure-resistance value fitting curve. Due to heat resistance of the flexible substrate material made of the polydimethylsiloxane material, the situation that the substrate materials such as polyethylene glycol terephthalate (PET) are easy to bend and deform in the laser direct writing process is avoided; crossing between the row electrodes and the column electrodes is avoided, and the structure is more optimized.

The invention belongs to the field of functional polymer hydrogel, and particularly relates to stretchable, compressible and anti-freezing organic hydrogel electrolyte as well as a preparation method and application thereof. The organic hydrogel electrolyte provided by the invention is formed by initiating polymerization of methacryloylethyl sulfobetaine and acrylamide through free radicals by taking dimethyl sulfoxide and water as solvents, and soybean protein is doped in a cross-linked network. The maximum fracture strain of the organic hydrogel electrolyte provided by the invention can reach 762.5%, the organic hydrogel electrolyte can still recover to an original state after being stretched by 500% or compressed by 80% for multiple times, and the organic hydrogel electrolyte has excellent mechanical properties. The room-temperature conductivity can reach 37.5 mS.cm<-1>, and the charging and discharging time is still 13s at -20 DEG C, so that the hydrogel electrolyte has good low-temperature electrical performance, and the technical effect of using the hydrogel electrolyte as a supercapacitor electrolyte can be realized. The hydrogel electrolyte has strain sensitivity, and the technical effect that the hydrogel electrolyte serves as a stable sensor material can be achieved.

The invention discloses a method for measuring the piezoresistive coefficient of a double-end fixed-supported beam based on SOI silicon wafers, which includes the following steps: through force analysis, it is obtained that under the action of an electrostatic force uniform load, the upper part of the double-ended fixed-supported beam is located at The size of the compressed area in the middle position is the length of the double-end fixed beam, and it is doped within this range; the two ends of the doped area are heavily doped; in the heavily doped area, the corresponding anchor Metal aluminum is deposited in the region and the region between the heavily doped region and the anchor region; multiple metal wires are connected on the anchor region; a semiconductor parameter tester capable of measuring resistance is connected between the metal wires in the two anchor regions; An external voltage source that can apply an electrostatic bias voltage is added between the metal wire in the anchor area and the electrode of the substrate; the piezoresistive coefficient of the double-terminal anchored beam is measured and calculated. The invention avoids the canceling effect of the tension region and the compression region in the double-end fixed support beam, and has accurate measurement results and simple and convenient measurement method.

The invention discloses a novel perovskite manganese-based oxide thin film material. The perovskite manganese-based oxide thin film material has the general chemical formula of La<0.67>(Ca<x>Ba<1-x>)<0.33>MnO<3>, wherein Mn is metal manganese and O is oxygen; and the perovskite manganese-based oxide thin film material has an ABO<3> type perovskite crystal structure. The perovskite manganese-based oxide thin film material is obvious in resistance change under an external magnetic filed and relatively high in magnetic resistance; the metal-insulation transformation temperature and magnetic resistance maximum value can be continuously adjustable along with content changes within a temperature range of 230-270K; and in addition, the thin film material has high magneto-electricity performance.

The invention provides a temperature chain sensor based on negative temperature coefficient thermistors; the temperature chain sensor comprises wires, filling material, a plurality of negative temperature coefficient thermistors and a hollow tube carrier; the plurality of negative temperature coefficient thermistors are fixed on the hollow tube carrier at certain intervals in sequence, thus forming the core member of the temperature chain sensor, wherein the hollow tube carrier is made of polycarbonate material; each fixed negative temperature coefficient thermistor is respectively connected to the outer side of the hollow tube carrier through the wire, and connected with an outer circuit in a half-bridge form, thus measuring the temperature of a measured object; a silica gel adhesive is filled in the internal gap of the hollow tube carrier. The temperature chain sensor is mainly applied to cold conditions in sea ice, polar areas, high plateaus and low temperature laboratories, and can measure the temperature gradient distribution in the ice body; the temperature chain sensor can provide very substantial resistance changes, and a disengaging signal amplifier is not needed; the temperature chain sensor is low in cost, and can be applied in large scale.

The invention relates to the technical field of microfluid pressure detection, and discloses a resistive microfluid pressure sensor, which comprises a fluid layer. A flexible thin layer is arranged onthe upper end surface of the fluid layer, and a microfluid pressure sensing cavity which is provided with a downward opening and protrudes towards the upper part of the flexible film layer is formedin the flexible film layer. An electrode layer is arranged on the upper end face of the flexible film layer, a pressure sensing liquid electrode cavity which is provided with a downward opening and protrudes towards the upper portion of the electrode layer is formed in the electrode layer, the microfluid pressure sensing cavity is formed in the pressure sensing liquid electrode cavity, and a buffer cavity is formed between the microfluid pressure sensing cavity and the pressure sensing liquid electrode cavity. A micro resistance signal measuring structure is respectively connected with a liquid electrode flow channel inlet and a liquid electrode flow channel outlet through leads. The resistive microfluid pressure sensor has the advantages of high resolution and sensitivity of fluid pressure detection and low manufacturing cost and low difficulty of the microfluid pressure sensor.

The invention discloses a flexible graphite alkene nanometer wall resistance type magnetic field detection device and a preparation method. The flexible graphite alkene nanometer wall magnetic field detection device comprises a detection member and parallel electrodes; the detection member consists of a pressure sensitive layer, a magnetic field induction layer and a flexible substrate; the pressure sensitive layer and the magnetic field induction layer are adhered to two sides of the flexible substrate; the parallel electrodes are arranged on the surface of the pressure sensitive layer; and the pressure sensitive layer is an alkene nanometer wall. The flexible graphite alkene nanometer wall resistance type magnetic field detection device overcomes the insufficiency of the current regular magnetic field detection device, has advantages of low power consumption, high sensitivity, high measurement accuracy and high stability, adopts the flexible substrate and can be widely applied in the occasions where the human body needs the flexible magnetic field detection device.

The invention discloses ionic conductive hydrogel as well as a preparation method and application thereof. The preparation method comprises the following steps: step 1, preparing a phenylboronic acid ionic liquid monomer; and 2, preparing the ionic conductive hydrogel according to the product obtained in the step 1. The multifunctional ionic conductive hydrogel provided by the invention is applied to a sensor and is prepared from the multifunctional ionic conductive hydrogel, and the two ends of the multifunctional ionic conductive hydrogel are connected with wires and packaged. The sensor comprises but is not limited to a man-machine interaction sensor, electronic skin and the like. The electronic skin is also called as a novel wearable flexible bionic tactile sensor.

The invention discloses a system for measuring the expansion degree of filter material. The system for measuring the expansion degree of filter material is provided with: a grit settling pan; the lower end of the grit settling plate with a filter screen is equipped with an orifice plate, and the upper end is equipped with a gland; at least A grit chamber is connected in series through fixing bolts to form a probe; the probe is fixed at one end of a hollow plastic conduit; one end of the wire protrudes symmetrically from the side wall of the grit chamber, the other end runs through the plastic conduit, and the other end of the plastic conduit protrudes to connect with the ohmmeter. connect. The invention is simple in structure, easy to carry and assemble, and the length of the conduit and the wire can be adjusted according to the depth of the filter tank (filter column) to be tested. The device for measuring the degree of swelling of the filter material can also be used in environmental protection, petroleum, chemical and other industries under appropriate conditions to measure the interface of liquid and sludge.

The invention discloses a conductive hydrogel composite material which is sensitive to humidity level fluctuation, a device and a preparation method, which relates to a smart material and a device and a preparation method, wherein, the conductive hydrogel composite material and the preparation method thereof comprises four steps of dispersion of conductive filling materials, in situ polymerization, casting to be shaped and electrode trimming; the conductive hydrogel composite material and the device comprise a hydrogel which is sensitive to humidity level fluctuation, the conductive filling materials and an additive. In the process of responding to the environmental moisture change, the obtained conductive hydrogel composite material and the device can make a sensitive response to the external moisture change. The conductive hydrogel composite material and the device can obtain practical applications in the fields of biomedicine, fluid control, diffusion and permeation, intelligent machinery and the like.

The invention provides a knee abutting presser foot lifting device of a sewing machine, and belongs to the technical field of clothing making equipment. The technical problem that an existing knee abutting presser foot lifting device is likely to be damaged is solved. The sewing machine comprises a pressing rod and a small presser foot arranged at the lower end of the pressing rod. A pressing spring sleeves the pressing rod, the presser foot lifting device comprises a lifting front lever and a lifting pull rod for driving the lifting front lever to swing, the end of the lifting pull rod is connected with a lifting rear lever, and the presser foot device further comprises an electromagnet, a knee controlled hinge shaft and a knee abutting disc. An output shaft of the electromagnet is connected with the middle of the lifting rear lever through a pull rod crank, the end of the knee controlled hinge shaft is connected with a rheostat, a limiting frame is arranged on the knee controlled hinge shaft, and a jacking assembly is arranged between the limiting frame and the lifting rear lever. The end of the jacking assembly is connected with the end of the lifting rear lever. The knee abutting presser foot lifting device saves more labor and is not likely to be damaged.

A shear strain type pressure sensor, comprising a housing, the magnetic field generating device in the housing has two opposite magnetic poles and corresponding to each other, a shearing plate is arranged in the space between the two magnetic poles, and the shearing plate One side of the shear plate is fixed with a rubber sheet, which is in full contact with the magnetic end surface of the first magnetic pole of the two magnetic poles, and the other side of the shear plate is fixed with a first electrode, and the first electrode is fixed with a magnetorheological Elastic body, the other side of the magnetorheological elastic body is fixed with a second electrode, the second electrode is fixed to the magnetic pole surface of the second magnetic pole in the two magnetic poles, the first electrode, the second electrode and a signal conditioning module Electrically connected, one end of the shearing plate extends upwards through an S-shaped force-measuring member and then protrudes from the upper surface of the housing, and the housing is fixed with a support plate for supporting the S-shaped force-measuring member. A stopper is arranged on the plate, and the lower end surface of the stopper is in contact with the upper end surface of the S-shaped force-measuring piece. It has high resolution, high sensitivity and large force range.

The invention discloses an overvoltage warning device and method based on a pressure sensor and an electrochromic device. The overvoltage warning device comprises a control circuit, a signal input line, a trigger pressure adjustment knob, a voltage display area, a delay adjustment knob, a delay trigger switch, an output line and an electrochromic device, wherein the control circuit is provided with a pressure sensor, a first slide rheostat, a voltmeter, an NPN triode, a second slide rheostat and a switch; the signal input line is extracted from two ends of the pressure sensor; the trigger pressure adjustment knob is connected with the first slide rheostat; the voltage display area is connected with the voltmeter; the delay adjustment knob is connected with the second slide rheostat; the delay trigger switch is connected with the switch; the output line is extracted from an output end; and the electrochromic device is connected with two ends of the output line. When the overvoltage warning device is triggered by pressure, the output voltage is immediately reversed, and the electrochromic device is enabled to change in color; and when the pressure is below a trigger value, the outputvoltage is enabled to be reversed again, and the electrochromic device is enabled to return back to be original color. The overvoltage warning device is simpler and more stable in control circuit, less in consumed electric energy, safer and more environment-friendly and has a good warning effect.

The invention provides a three-dimensional flexible sensor material as well as a preparation method and application thereof, and the preparation method of the sensor material comprises the following steps: adding a conductive agent, a binder and a reinforcing agent into water, and uniformly dispersing to obtain printing ink; the printing ink is made into a device in a 3D printing mode, and then the device is soaked in a cross-linking agent solution; and drying the device containing the cross-linking agent in a freeze-drying manner to obtain the cross-linking agent. The flexible sensor can effectively solve the problems that an existing sensor is large in hardness and poor in fitting degree.

The invention discloses a piezoresistive type flexible tactile sensor with double-layer fastener type micro-bosses. The sensor is formed by stacking a semi-spherical protrusion, an upper-layer micro-boss array, a stretchable electrode array, a flexible pressure-sensitive array and a lower-layer micro-boss array structure which are arranged sequentially from top to bottom, wherein the flexible pressure-sensitive array is composed of a linear graphene pattern array and a flexible thin-film substrate; and the stretchable electrode array is composed of row and column strip-shaped electrodes and circular insulating barriers between the row and column strip-shaped electrodes. The stretchable electrode array is tightly attached to the flexible pressure-sensitive array; and square pins are arranged on the two sides of each linear graphene pattern, and are connected with the row and column strip-shaped electrodes respectively to form a closed loop. The double-layer fastener type micro-bosses are adopted to convert an external force effect on the tactile sensor into tensile deformation of the linear graphene patterns in the flexible pressure-sensitive array, so that the resistance change ofthe pressure-sensitive array is more obvious, and the sensitivity of the tactile sensor is improved; and meanwhile, the flexible design of the tactile sensor is realized by adopting a conductive composite material.