42 results about "Piezoresistive effect" patented technology

The invention discloses a flexible multi-dimensional force sensing device, comprising a first insulator having a plurality of three-dimensional structures protruding from the surface; the first conductor is made of a flexible conductive material and is in the shape of long-strip stitches, the stitches are connected with one another to form a conductive network, the stitches are adhered to the surface of the first insulator and distributed on the surface of the three-dimensional structure unit, and the three-dimensional structure unit is used for transmitting borne normal pressure, shear force and torsional force to the corresponding stitches; the first conductor has a piezoresistive effect, when the first conductor is stressed to generate elastic deformation, the stitch is stretched or compressed, and the resistance at the stressed position changes regularly; and connecting each trace of the first conductor to an external electrical impedance scanning imaging device so as to detect pressure information of each position on the surface of the flexible multi-dimensional force sensing device at each moment. On the basis, the flexible multi-dimensional force sensing equipment is simple in structure, low in cost, easy to process, good in fitting degree for a curved surface shape, and excellent in stability and robustness.

The invention discloses a self-calibration flexible pressure sensing device, which comprises a first conductor and a second conductor which are in a strip-shaped, strip-shaped or linear structure and both have a piezoresistive effect. The isolating layer is arranged between the first conductor and the second conductor, and through holes or long grooves with continuous through holes are distributed in the surface of the isolating layer; and an encapsulation layer covering the first conductor and the second conductor. According to the embodiment of the invention, a dual-core layer piezoresistive structure and a through hole type isolation layer design are adopted, the dual-core layer design covers a range from small pressure to large pressure, the range limitation of a single material is broken through, and a dynamic self-calibration technology is combined, so that multi-parameter integrated detection of pressure magnitude, position and width is realized; the sensor array has the advantages of self-adaption to environment change, wide-range detection, multi-scene applicability and the like, the sensor for realizing the functions only needs four wires, complex wiring of the sensor array is avoided, miniaturization and flexibility are facilitated, a narrow strip-shaped flexible structure is adopted as a whole, and flexible arrangement of sensor tracks and garment integration are facilitated.

The invention belongs to the technical field of pipeline repair, and particularly relates to a nano conductive composite material pipeline repair layer health monitoring system and method based on a piezoresistive effect. The invention discloses a nano conductive composite material pipeline repair layer health monitoring system based on a piezoresistive effect. The system comprises a sensing layer, a data acquisition layer, a transmission layer, an analysis layer and an application layer, wherein the sensing layer is a graphene / carbon nanotube hybrid reinforced composite material pipeline repairing layer made of a self-sensing material; the data acquisition layer is used for acquiring signals and carrying out multi-channel acquisition, signal conditioning, A / D conversion and time synchronization; the transmission layer performs data communication through wired transmission / wireless transmission; the analysis layer performs data processing and algorithm processing including data preprocessing, trend analysis, damage identification and a positioning algorithm; and the application layer realizes user interaction and display, and performs visual interface, alarm push, operation and maintenance decision and report generation. The invention provides a nano conductive composite material pipeline repair layer health monitoring system and method based on a piezoresistive effect, and aims to solve the problems of no basis for conductive threshold design, insufficient monitoring sensitivity, incomplete system, indefinite alarm criterion, low positioning precision, low intelligent degree, high cost and the like in the prior art.

The invention belongs to the technical field of bearings, and discloses a foil dynamic pressure radial gas bearing bump foil creep test method, which is characterized in that a miniature rubber block is inserted between a top foil and a rigid substrate, and the miniature rubber block is used as a flexible element, is in direct contact with the top foil, and deforms under the action of a compression load transmitted by the top foil; a monocrystalline silicon semiconductor strain gauge is pasted on the side face of the miniature rubber block, and the direction is perpendicular to the direction of the compression load; in the running process of the bearing, the output strain value of the strain gauge is monitored in real time through a data acquisition system; the semiconductor strain gauge is a sensitive element manufactured based on the piezoresistive effect of semiconductor monocrystalline silicon, the resistivity of a semiconductor crystal material is changed when the semiconductor crystal material is stressed in a certain direction and deforms, and strain, stress and the like are indirectly measured. The device has the beneficial effect that the problem that the creep strain is difficult to test in real time due to the tiny structure of the bump foil is solved.

The invention discloses a pressure measuring device and a measuring method, particularly relates to the technical field of pressure measurement, and solves the technical problem that a pressure measuring device in the prior art is not suitable for teaching. According to the technical scheme, a double-strip-shaped copper foil electrode is fixed to the surface of an acrylic bearing plate, 8B pencil graphite EVA foam covers the double-strip-shaped copper foil electrode to form a sensor, and the tail end of the electrode is connected with a wire to be connected into a Wheatstone bridge; a bridge output signal is sampled by 860SPS through an ADS1115 module, and meanwhile, the NTC thermistor compensates the temperature drift in real time; the sensor receives pressure and then is connected with the Arduino through a wire to convert and output pressure change to a computer for real-time display; according to the invention, students can deeply understand a piezoresistive effect principle through a low-cost self-made device, observe dynamic pressure changes in real time, and explore a pressure distribution rule.

The embodiment of the invention discloses wearable knee joint equipment, a knee joint rehabilitation evaluation method and computing equipment. The wearable knee joint equipment comprises a flexible substrate; the sensing unit is integrated on the flexible substrate and comprises an electromyographic sensing module used for collecting surface electromyographic signals of rectus femoris for driving the knee joint to move; the muscular tension sensing module is used for generating a muscular tension signal by detecting skin deformation caused by knee joint movement based on the piezoresistive effect; the joint angle sensing module is used for generating a knee joint motion range signal by detecting knee joint flexion and extension strain based on the piezoresistive effect; the signal processing module is connected with the sensing units and used for processing and wirelessly transmitting the surface electromyogram signals, the muscular tension signals and the knee joint movement signals to a computing device so that the computing device can determine the state evaluation result of the knee joint rehabilitation state based on the signals. The possibility is provided for remote dynamic monitoring of TKA postoperative rehabilitation, and the accuracy of rehabilitation state evaluation is improved.

This utility model discloses a MEMS multidimensional force sensor, relating to the field of sensor technology. It includes a sensor body comprising an upper mounting flange, a lower mounting flange, an elastomer, and strain gauges. The elastomer is mounted between the upper and lower mounting flanges, and the strain gauges are adhered to the surface of the elastomer. The elastomer employs an asymmetric structure, and the strain gauges are flexible MEMS strain gauges capable of converting the deformation of the elastomer into a change in resistance through the piezoresistive effect. This utility model achieves synchronous decoupled measurement of X, Y, and Z forces and Mx, My, and Mz moments by setting four sets of asymmetric strain beams around the central strain table and arranging sixteen sets of flexible MEMS strain gauges in the key stress concentration areas of each crossbeam and longitudinal beam. This effectively reduces interdimensional coupling errors and improves the accuracy of multidimensional force detection.

The present application relates to a kind of sensor for capturing and identifying pressure signal and its preparation and application.The sensor is realized by piezoresistive effect pressure sensing, which is composed of three parts of sensitive layer, electrode, encapsulation layer.Sensitive layer is graphene composite silk fibroin aerogel material, its feature is with ordered three-dimensional porous layered structure, with small density, electrically conductive, compressible-rebound, non-toxic and other characteristics;Electrode is high-conductivity material, and encapsulation layer is flexible scalable polymer material.Benefiting from the excellent piezoresistive change and compression-rebound performance of graphene composite silk fibroin aerogel, the prepared flexible pressure sensor can not only quickly detect pressure and deformation, but also has excellent flexibility and durability.In addition, the preparation method of the sensor is simple, raw material is green and environmentally friendly, detection range is wide, and sensitivity linearity is high.Therefore, the sensor has the potential of large-scale manufacturing, and has broad application prospects in the field of flexible wearable electronic equipment.

The application provides a slope piezoelectric intelligent pavement weighing characterization method based on a multi-axle heavy vehicle. The method first selects a to-be-detected pavement, and arranges a piezoelectric sensor array on the cross section of the to-be-detected pavement to form an intelligent pavement. When the vehicle passes through the intelligent pavement, the piezoresistive effect of the piezoelectric sensor converts the mechanical strain into an electric charge signal output. Then, a corresponding voltage signal is generated through a charge-voltage converter, and the relationship between the voltage and the pressure is established in combination with the sensitivity information on the piezoelectric sensor. Based on the pressure distribution data, the position of each wheel of the vehicle is determined. The vehicle speed is calculated in combination with the time interval and the position data of the wheel. Based on the pressure data and the wheel position information, the relationship between the pressure and the load is established, and then the weight applied by each wheel is calculated. The application can significantly improve the weighing accuracy under the condition of a slope pavement, and provides a more reliable and efficient solution for the weighing problem of the multi-axle heavy vehicle.

The invention discloses a shale proppant embedding damage in-situ real-time monitoring system and a shale proppant embedding damage in-situ real-time monitoring method, a self-sensing shale sample assembly with an innovative structure is adopted, and a conductive sensing layer in the self-sensing shale sample assembly is extremely high in electric signal response speed based on a piezoresistive effect; in the load test process, the whole process dynamic state of embedding, compacting and crushing the upper shale sample and the lower shale sample by the proppant is completely recorded, and in-situ real-time monitoring data is obtained; the conductive induction layers are made of specific materials and are coated on the stress surfaces of the upper shale sample and the lower shale sample and the non-stress surfaces of the side walls of the upper shale sample and the lower shale sample, the conductive induction layers with lateral extension structures are formed after the conductive induction layers are cured, and lateral electrode sensors are installed on the side walls of the two samples respectively. According to the structure, the lateral electrode sensor is prevented from being directly damaged by vertical high-pressure load, sensitive capture of the dynamic embedding process of the proppant is ensured, and finally the embedding depth of the proppant is calculated in real time according to monitoring data, so that the embedding damage condition of the proppant is accurately determined in real time.

The invention discloses a pressure sensor based on a non-metal suspended structure-two-dimensional material-metal mixed structure, and the pressure sensor comprises a substrate structure which comprises a solid material substrate and a non-metal suspended structure located on the solid material substrate, and a cavity formed through etching is formed below the non-metal suspended structure; the pressure-sensitive layer is positioned on the non-metal suspended structure, is made of a single-layer or multi-layer conductive two-dimensional material and forms a pressure sensing functional area; the electrode layer is located on the pressure-sensitive layer, comprises at least two metal electrodes and is used for being connected with an external circuit and conducting electrical signals. The invention also discloses a preparation method and application of the pressure sensor. According to the invention, the excellent piezoresistive effect of the two-dimensional material is fully utilized, high-sensitivity pressure detection is realized on a planar microstructure, the size is small, the integration degree is high, and the application coverage is wide.

The application discloses a kind of robot tactile perception and force error compensation systems for circuit breaker operation and maintenance, it is related to power equipment operation and maintenance automation technical field, including tactile perception module, using piezoresistive effect flexible sensor array, support 16-way data synchronous acquisition;Force error compensation module, integrated impedance control algorithm and multi-source error compensation model;System control module, using industrial grade embedded controller, support CAN bus and Ethernet communication;Environment adaptation module, deployment temperature and humidity and vibration sensor, dynamic adjustment parameter;Execution drive module, contain servo driver and adaptive clamping mechanism;Data storage and analysis module, using edge-cloud architecture;Safety protection module, with over force protection and insulation monitoring function.The application improves tactile perception precision and force error compensation effect, enhances complex environment adaptation capability;Through self-calibration and data optimization, keep long-term stable operation, adapt to different specifications circuit breaker operation and maintenance demand.

A broadband graphene array type transceiving integrated flexible transducer for bionic underwater communication belongs to the technical field of broadband underwater acoustic transducers and comprises a plurality of transceiving integrated transduction array units with graphene composite materials as core functional layers. The array unit comprises a graphene composite material core function layer, conductive metal film layers located on the upper surface and the lower surface of the graphene composite material core function layer, an elastic substrate layer located on the upper portion and a waterproof protection layer. The graphene composite material core function layer emits broadband underwater acoustic signals based on the thermo-acoustic effect and receives the underwater acoustic signals based on the piezoresistive effect. And the conductive metal film layer is connected with other transduction array units through flexible insulated wires for electric signal transmission. According to the invention, each array unit has the functions of underwater acoustic signal transmitting and receiving at the same time, and the structure is simple; the composite material has excellent flexibility, excellent hyperelasticity and excellent mechanical strength, and provides a device breakthrough for the fields of bionic marine environment monitoring, underwater operation monitoring and the like.

This invention provides a method and device for monitoring roadbed moisture content based on the piezoresistive effect. By embedding a strain-sensitive sensor arranged in a spiral pattern within the wall of a drainage pipe, the method monitors the sensor's resistance change rate under vehicle vibration loads in real time. Combined with synchronously measured soil stress, and based on a pre-calibrated empirical model of moisture content-elastic modulus, the real-time volumetric moisture content of the roadbed soil is calculated. This invention solves the technical problem of traditional detection methods' difficulty in long-term, real-time monitoring of roadbed internal moisture content, achieving long-term, non-destructive monitoring of roadbed moisture content and providing an effective means for preventative road maintenance and stability assessment.

The invention relates to the technical field of MEMS sensors, in particular to a high-performance silicon piezoresistive pressure-sensitive flip chip. According to the invention, a nesting combination design of axial symmetry, central symmetry and symmetrical front and back piezoresistive sensitivity of a homodromous single-straight-strip piezoresistive bridge resistance sensitive structure and effect is adopted, so that the sensitive chip has the performance advantages of high linearity, high accuracy, consistent front and back piezoresistive effect sensitivity and non-linear symmetry, and strong overload pressure capability; the device is suitable for accurate measurement of negative gauge pressure, gauge pressure, negative absolute pressure, absolute pressure and differential pressure. The inverted packaging of the sensitive chip does not need isolation liquid sealing and movable lead bonding, the inherent frequency height and width advantage is suitable for high-frequency dynamic pressure measurement, and the long-term reliable working temperature upper limit can reach the Young modulus limiting temperature 556 DEG C of monocrystalline silicon.

A pressure sensing system that includes a dual-function foam is disclosed. The dual-function foam may be integrated into padding of a variety of objects to measure pressures and locations of pressures / strains exerted by a user on the padding. The dual-function foam may respond to a pressure / strain with a piezoelectric effect or a piezoresistive effect depending on the nature of the applied pressure / strain. Each effect may require different sensing approaches. Accordingly, the pressure sensor system may include a controller that is configurable into one of a plurality of operating modes based on the sensing approach suitable for the applied pressure / strain. One of the operating modes may be a sleep mode, which can reduce the power consumed by the controller when no pressure / strain is applied to the dual-function foam for a period.

The invention discloses a piezoelectric pressure sensor and a preparation method thereof. The piezoelectric pressure sensor includes: a substrate; the piezoelectric driving layer is positioned on one side of the substrate; the first cavity penetrates through at least part of the substrate along a first direction; the first direction is the thickness direction of the substrate; the limiting structure is located in the first cavity, and the distance between the limiting structure and the piezoelectric driving layer meets a preset distance range. According to the piezoelectric pressure sensor, the limiting structure used for limiting the piezoelectric driving layer is arranged in the first cavity, so that additional damping, resonance, stress, electrostatic noise and piezoresistive effect cannot be introduced through the arrangement of the limiting structure, and the influence of the limiting structure on the response speed and the measurement precision of the piezoelectric pressure sensor can be reduced; and compared with the scheme that the limiting structure is arranged on the mounting plate or the packaging structure, the size of the piezoelectric pressure sensor can be reduced.

A pressure sensing system that includes a dual-function foam is disclosed. The dual-function foam may be integrated into padding of a variety of objects to measure pressures and locations of pressures / strains exerted by a user on the padding. The dual-function foam may respond to a pressure / strain with a piezoelectric effect or a piezoresistive effect depending on the nature of the applied pressure / strain. Each effect may require different sensing approaches. Accordingly, the pressure sensor system may include a controller that is configurable into one of a plurality of operating modes based on the sensing approach suitable for the applied pressure / strain. One of the operating modes may be a sleep mode, which can reduce the power consumed by the controller when no pressure / strain is applied to the dual-function foam for a period.

The utility model relates to the technical field of industrial automatic measurement, in particular to a monocrystalline silicon double-flange remote differential pressure transmitter, which comprises a main body, and a transmitter assembly is fixedly connected to the top of the main body. According to the utility model, the monocrystalline silicon differential pressure sensor is used as a core measuring element of the transmitter, the transmitter has high precision, high stability and good linearity, the working principle of the transmitter is based on the piezoresistive effect of monocrystalline silicon, when differential pressure acts on the pressure sensing diaphragm of the sensor, the diaphragm is slightly deformed, and the strain resistance value is changed, so that the pressure sensing diaphragm of the sensor can be accurately measured. The signal processing circuit amplifies and filters weak signals output by the monocrystalline silicon differential pressure sensor, the remote transmission sealing capillary tube is made of stainless steel and has good pressure resistance and corrosion resistance, the pressure of a measured medium can be transmitted to the monocrystalline silicon differential pressure sensor, and the pressure of the measured medium can be further changed. The length of the remote transmission sealing capillary tube is a specified length, so that lagging and errors in the pressure transmission process are reduced.

The present application relates to the technical field of piezoresistive sensor, and provides a preparation method of piezoresistive sensor based on PN junction type of carbon-based material.The present application mixes reduced graphene oxide and graphene oxide suspension to obtain a mixed solution, coats the mixed solution on a substrate and dries to obtain the piezoresistive sensor based on PN junction type of carbon-based material.Through the mixing method, the present application adopts the reduced graphene oxide to simply dope the graphene oxide, and then obtains the piezoresistive sensor based on PN junction type of carbon-based material through coating and drying.The present application does not need to carry out complex chemical vapor deposition, nor needs to adopt wet spinning, heat annealing and other steps, and the preparation method is very simple and easy to operate, and the obtained piezoresistive sensor based on PN junction type has good piezoresistive effect and rectification characteristics, and has wide application prospect.

The invention discloses a micro temperature-stress integrated sensor for multi-core particle packaging and a multi-core particle packaging structure. The integrated sensor comprises a temperature sensor and a stress sensor. The temperature sensor adopts a metal resistor, and accurate temperature measurement is realized by utilizing a high resistance temperature coefficient and a low resistance coefficient of the metal resistor; the stress sensor adopts a Wheatstone bridge formed by alloy piezoresistive strips, and accurate stress measurement is realized by using a remarkable piezoresistive effect and a low resistance temperature coefficient of the Wheatstone bridge. The two kinds of sensors are integrated on the same substrate through a semiconductor technology to form an integrated sensing module which is physically independent and has synergistically decoupled signals. The invention provides two schemes which can be embedded into a multi-layer rewiring layer of core particle packaging, and high-precision monitoring of the internal temperature and stress of the multi-core particle packaging structure is realized through decoupling of temperature and stress signals by a subsequent signal conditioning circuit, so that optimization and reliability evaluation of the multi-core particle packaging structure are realized.

This invention discloses a dual-response phase change hydrogel material for battery thermal management and its preparation method. The material is composed of water, N-isopropylacrylamide, polyvinyl alcohol, polyethylene glycol, graphene, a crosslinking agent, and an initiator in specific mass percentages. Its core feature is its dual-response characteristics of temperature and pressure: in terms of temperature response, the material undergoes a reversible solid-liquid phase change at approximately 35.2℃ for daily temperature control, and suppresses thermal runaway through a strong endothermic phase change in the 60-80℃ range; in terms of pressure response, the material possesses a piezoresistive effect, which can sensitively detect changes in internal battery pressure and provide early warning. This material also exhibits high thermal conductivity (≥3.7 W / (m·K)), excellent structural stability, and mechanical properties. Its preparation method mainly includes mixing the components, heating and dissolving, mold casting, and ultraviolet curing. This material is particularly suitable for intelligent battery thermal management in electric vehicles, energy storage systems, and other fields, and can significantly improve the safety and reliability of the system.

The utility model relates to the field of pressure sensing, and discloses a flexible pressure sensor for breath detection. The sensor comprises a first protective layer, a first electrode layer, a conical pressure-sensitive array, a flexible substrate, a second electrode layer and a second protective layer. The conical pressure-sensitive array consists of conical microstructures and is positioned between the first electrode layer and the flexible substrate; the second electrode layer is located on the lower side of the flexible substrate; the first and second protection layers are respectively arranged on the upper and lower sides of the first and second electrode layers. When the sensor is subjected to laryngeal respiratory pressure, the conical pressure-sensitive array deforms, the contact area between the conical pressure-sensitive array and the electrodes is rapidly increased, the resistance is rapidly reduced, the pressure is converted into a resistance signal, and stable detection of respiratory signals is achieved by measuring the resistance value of the sensor through the piezoresistive effect. The system has the characteristics of high response speed, high sensitivity and strong stability, and provides a wide application prospect for wearable equipment and health detection.

The invention relates to the technical field of sensing materials, and discloses a low-power-consumption sensing coating material for monitoring the service life of automobile calipers and an application method of the low-power-consumption sensing coating material for monitoring the service life of the automobile calipers. 20 to 40 parts of crystalline flake graphite; 5 to 20 parts of nano silver particles; 5 to 20 parts of hexagonal boron nitride nanosheets; and 0.5-5 parts of a silane coupling agent. According to the invention, resistance temperature self-compensation is realized by compounding crystalline flake graphite and nano-silver particles; the piezoresistive effect is inhibited by using the hexagonal boron nitride nanosheets; and a silane coupling agent and a polyimide matrix are adopted to ensure strong binding force and environmental stability of the coating and a metal substrate. The coating is arranged in the abrasion area of the caliper, and the reduction amount of the thickness of the coating is monitored by measuring the change of a resistance value. The problems that an existing sensing coating signal is prone to being interfered by temperature and pressure and the environment stability is poor are solved, and accurate, reliable and long-acting monitoring on abrasion of the automobile calipers is achieved.

The invention discloses an anti-electromagnetic interference MEMS piezoresistive differential pressure sensor and a manufacturing method thereof, the sensor is based on a piezoresistive effect, a piezoresistor is manufactured on a sensitive film to form a Wheatstone bridge, and two sides of the sensitive film are respectively connected with two pressure inlets to realize differential pressure measurement. According to the sensor, two SOI silicon wafers are adopted as a first substrate and a second substrate, and the differential pressure sensor is formed through a micromachining and bonding technology; the piezoresistor is electrically connected with the outside through a silicon through hole so as to reduce electromagnetic coupling in a signal transmission process; the surface of the sensor is covered with a passivation layer, electrical isolation inside a chip is achieved through a buried oxide layer in an SOI silicon wafer, and leakage current and medium interference are effectively reduced. Shielding layers cover the upper and lower surfaces of the sensor and are connected to the same potential to form a Faraday cage structure to realize electromagnetic shielding. The sensor has the characteristics of simple structure, low cost, quick response and the like, and the reliability of the sensor in a strong electromagnetic environment is remarkably improved.

A method for preparing a suspended two-dimensional film and its application in a nano-electromechanical pressure sensor. In the pressure sensor, a suspended two-dimensional material or a suspended two-dimensional hetero-layer is used as a sensitive film. The suspended two-dimensional material or the two-dimensional hetero-layer is covered on a cavity of an oxidized silicon substrate, and an electrode is connected to the suspended two-dimensional material and the hetero-layer. When an external pressure changes (for example, decreases), the suspended two-dimensional material or the two-dimensional hetero-layer deforms correspondingly (for example, deforms in the opposite direction of the cavity). According to the piezoresistive effect of the two-dimensional material, the resistance of the suspended two-dimensional material or the two-dimensional hetero-layer changes, and the corresponding change can be detected to correspondingly detect the change of the external pressure.

The application provides a friction piezoelectric hybrid energy harvester for axle vibration signal acquisition system power supply, which comprises a ring chain, an energy acquisition module, a flexible sensing module, a voltage reduction circuit and a wireless communication unit; the ring chain is tightly covered on the outer periphery of the axle and rotates synchronously with the axle, the energy acquisition module, the voltage reduction circuit and the wireless communication unit are fixed on the ring chain, and the flexible sensing module is attached to the surface of the axle. The energy acquisition module adopts a V-shaped shell and a magnetic repulsion type bistable swing piece, integrates piezoelectric power generation and friction power generation to realize hybrid energy harvesting, and converts the mechanical energy of the axle rotation into electrical energy; the flexible sensing module realizes real-time acquisition of the strain state signal of the axle based on the piezoresistance effect, the electrical energy is used to supply power to the sensing and wireless communication unit after voltage reduction management, and wireless transmission of the monitoring signal is realized. The application can be directly installed on the surface of the axle, integrates self-powered, state sensing and wireless communication functions, and is suitable for real-time online health monitoring of the axle of trains, engineering machinery and other equipment.

The invention provides a breathing machine control method and system. The method comprises the steps that firstly, a resistance change signal which is caused by the autonomous breathing airflow change of a patient and generated through the piezoresistive effect of a functional layer is obtained from an electrode layer of an intelligent piezoresistive airflow management module; performing digital filtering on the signal, extracting a preset frequency band signal, determining local strain according to resistance change and a strain calibration curve, calculating a strain change rate, identifying adjacent electrode nodes of which the resistance change exceeds a threshold value, and calculating an effective area; calculating driving energy according to the local strain, the strain change rate, the effective area and functional layer carbon quantum dot concentration distribution obtained from a pre-stored lookup table; and finally, generating a voltage pulse according to the driving energy, applying the voltage pulse to the target micro valve through the electrode layer, heating the functional layer, and triggering the bionic molecular ratchet mechanism to open the micro valve. According to the method, sensing and executing atomic-scale collaboration are achieved, signal transmission processing delay is eliminated, man-machine synchronism is improved, lung differentiation ventilation can be achieved, and the defects in the prior art are overcome.

The invention belongs to the technical field of radioactivity detection, and particularly relates to a piezoresistive MEMS miniature high-dose radiation detector structure which comprises a radiation sensitive layer, a strain amplification layer and a base layer which are arranged in sequence, a radiation sensitive material (3) arranged on the radiation sensitive layer generates controllable volume expansion after absorbing radiation, and the strain amplification layer is arranged on the base layer. And the strain amplification layer converts volume expansion into mechanical strain, converts the strain into resistance change by utilizing a piezoresistive effect, and is connected with a Wheatstone bridge and an external detection circuit to measure the variable quantity of output voltage so as to realize radiation dose measurement. The capability of measuring high-dose and high-energy radiation (greater than 10 kGy) and the advantage of direct sensing are combined together, miniaturization (the chip scale size is less than or equal to 5 mm * 5 mm * 1 mm) and high-dose range coverage (1 kGy to 100 kGy) are realized, and the distributed dose monitoring requirement in an extreme environment is met; the device is passive, free of maintenance, resistant to radiation damage and suitable for monitoring the accumulated radiation dose in the fields of nuclear industry, aerospace, medical irradiation and the like.

The invention provides a roadbed moisture content monitoring method and device based on a piezoresistive effect, and the method comprises the steps: enabling a strain sensitive sensor which is spirally arranged in a surrounding manner to be embedded in a drainage pipe wall, monitoring the resistance change rate of the sensor under a vehicle vibration load in real time, and carrying out the real-time monitoring of the resistance change rate of the sensor in combination with synchronously measured soil stress; and inverting the real-time volumetric moisture content of the roadbed soil body based on a pre-calibrated moisture content-elastic modulus empirical model. The method can solve the technical problem that the traditional detection method is difficult to monitor the moisture content in the roadbed for a long time in real time, realizes long-term nondestructive monitoring of the moisture content of the roadbed, and provides an effective means for preventive maintenance and stability evaluation of roads.