408 results about "Wheatstone bridge" patented technology

The invention discloses an MEMS thermal flow sensor based on a glass film structure and a preparation method of the MEMS thermal flow sensor. The sensor comprises a glass inner silicon substrate, a back cavity, a silicon through column, a heating resistor, a temperature measurement resistor, an environment temperature measurement resistor, a chromium adhesion layer, a PAD port and a silicon nitride protection layer. Wherein the heating resistor is located in the center, and the temperature measuring resistors are symmetrically distributed on two sides of the heating resistor; the back cavity is located on the back of the glass inner silicon substrate, and the heating resistor, the temperature measuring resistor and the environment temperature measuring resistor lead a PAD port to the back of the glass inner silicon substrate through a silicon through column. A thermal temperature difference principle is adopted, and upstream and downstream temperature measuring resistors form a Wheatstone bridge. When the flow velocity is not zero, the Wheatstone bridge outputs, and the larger the flow velocity is, the larger the output is. Based on the glass and silicon composite substrate, the suspension film structure is formed through the silicon etching process, transmission of heat to the substrate is greatly reduced, and the heat utilization rate is increased.

Disclosed in the present invention is a stepped elastic beam for a six-axis force sensor. The stepped elastic beam comprises a central platform, a stepped main beam, a floating beam, rims, and strain gauges, wherein the central platform is connected to the floating beam on the outer side by means of the stepped main beam, and the rims at four corners are connected to the floating beam; 24 strain gauges are pasted to the stepped main beam to form six sets of Wheatstone bridges; and when the force / torque of a certain dimension acts on the center of the stepped elastic beam, the sensor deforms, and the resistance value of the strain gauge at a corresponding position is changed, such that an output voltage of a corresponding bridge is changed, and the numerical value of the force / torque of the dimension can be obtained by measuring the change of the voltage. A structure is simple, the sensitivity is high, and the inter-dimensional coupling is low.

The invention discloses a microwave cold noise source fusing TEC temperature control and noise temperature compensation technologies, and belongs to the technical field of microwave radiometer calibration. The device comprises a cold source module, a noise compensation module and a constant-temperature control module, wherein the cold source module generates a low-temperature noise signal through a field-effect tube and a terminal resistor; the noise compensation module detects environment temperature change in real time based on a thermistor and a Wheatstone bridge, drives a noise diode to generate a compensation signal, couples the compensation signal with a cold source noise signal after attenuation, and counteracts noise temperature deviation caused by the environment temperature. The constant temperature control module adopts a platinum resistance sensor and a PID algorithm to control a Peltier element in a closed-loop mode, and accurate adjustment (+ / -0.1 DEG C) is achieved. According to the invention, noise compensation and TEC negative feedback temperature control technologies are combined, so that the noise temperature of the system is stabilized in a range of + / -0.1 K for a long time, the measurement precision and reliability of the microwave radiometer in an outdoor complex environment are remarkably improved, and the method is suitable for scenes of remote sensing detection, unmanned aerial vehicle monitoring and the like.

The invention discloses an integral type portable six-dimensional force measuring plate, which comprises an elastic body and a protection assembly arranged outside the elastic body, and further comprises a hub, a stress table and a plurality of strain beams, the stress table is arranged in the middle of the hub, the hub is connected with the stress table through the plurality of strain beams, a plurality of strain gauges are adhered to different positions of the strain beams, and the elastic body is connected with the hub through the strain gauges. A through hole is formed in the middle of the stress table, a bridge assembly plate for forming Wheatstone bridges and a data acquisition plate for acquiring and converting output signals of the elastomer are arranged in the through hole, and a plurality of wires are led out from the strain gauges and are welded to the bridge assembly plate to form six Wheatstone bridges which are respectively used for detecting forces and moments in three directions, namely Fx, Fy, Fz, Mx, My and Mz. The integrated force measuring plate has the advantages that the integral force measuring plate does not need to be spliced by a plurality of sensors, a plurality of beams can act together to balance stress and compensate each other, the influence of unbalance loading on a measuring result is reduced, and a plurality of force measuring plates can be spliced for use.

The invention provides a self-calibration method of a TMR (Tunnel Magnetoresistive) sensor and a TMR sensor array for current measurement, and relates to the technical field of quantum current sensors. According to the method, a double Wheatstone bridge structure is adopted, a to-be-measured bridge is used for measuring a to-be-measured magnetic field, and a reference bridge is used for measuring a known reference magnetic field; the self-calibration of the TMR sensor is realized by calculating the ratio of the output voltages of the two bridges, so that measurement errors caused by environmental factors such as temperature, humidity and mechanical vibration are eliminated; moreover, the invention provides a TMR sensor array for current measurement, the application of the TMR sensor array further enhances the adaptive capacity of the TMR sensor array in a complex environment, and the array is formed by a plurality of TMR sensor units, so that not only can the spatial resolution of measurement be improved, but also the fault-tolerant capability of the system can be improved through redundancy configuration, and the system reliability is improved. The array structure enables the TMR sensor to perform accurate measurement at a plurality of measurement points at the same time to obtain accurate measurement current.

The invention provides an MEMS pressure sensor and a manufacturing method thereof, and an electronic device, and the method comprises the steps: providing a first substrate, forming at least two first pressure structures on the surface of the first substrate, each first pressure structure comprises a first electrode layer, a first sacrificial layer, a first supporting layer, a second electrode layer, a second supporting layer, and a first cavity, and a first release hole; a second substrate is provided, at least two second pressure structures are formed on the surface of the second substrate, and each second pressure structure comprises a third electrode layer, a second sacrificial layer and a second cavity; bonding the second supporting layer with the second sacrificial layer; the second substrate is removed to expose the third electrode layer, the third electrode layer and the second electrode layer form a variable capacitance structure, the second electrode layer and the first electrode layer form a reference capacitance structure, and the two variable capacitance structures and the two reference capacitance structures jointly form a Wheatstone bridge. According to the scheme, the measurement precision is improved, and the device performance is further improved.

The invention relates to an asymmetric multichannel thermal flow sensor for integrated component detection and a signal processing method, and belongs to the technical field of sensors. The problems that a traditional symmetrical single-channel thermal flow sensor is limited in measuring range, saturated in output, insufficient in measuring precision and single in measuring flow are solved. The sensor comprises a flow inlet cavity, a flow outlet cavity and a measuring pipeline composed of five parallel circular pipelines, the middle pipeline is a component measuring pipeline, and the four pipelines on the periphery are flow measuring pipelines. A probe is arranged in the middle of the component measuring pipeline, a heating resistance wire is arranged in the middle of the flow measuring pipeline, and temperature measuring resistance wires are asymmetrically distributed on two sides. The pipeline is made of aluminum, and fillets are arranged at the joints to optimize fluid flow. The heating resistance wire is a nickel chrome wire, the temperature measuring resistance wire is a platinum wire, the component measuring probe is made of a platinum film, and the surfaces of the platinum film and the platinum film are insulated. An improved Wheatstone bridge circuit is adopted for signal collection, and precision and protectiveness are improved.

The invention relates to the technical field of sensors, in particular to a rigid-flexible coupling rotating body deformation sensor based on full-flexible design and a testing method. The sensor comprises an annular main body; the annular main body is a closed ring formed by alternately connecting a plurality of rigid arcs and a plurality of flexible arcs; the rigid arc and the flexible arc are arranged in a manner of meeting dynamic balance; the plurality of micro data acquisition devices are respectively integrated on each rigid arc; the miniature data acquisition device comprises a Wheatstone bridge, a filtering module, a digital potentiometer, an analog-to-digital conversion module, a digital acquisition module, a single-chip microcomputer, a wireless signal sending module and a battery unit. The plurality of strain gauge groups are respectively arranged on the outer surface of each flexible arc; and the thickness of the flexible arc is uniform. According to the invention, deformation adaptation and high-sensitivity measurement are realized through a rigid-flexible arc alternating structure, and convenient monitoring under a rotation working condition is realized through a wireless communication miniature data acquisition device.

The invention discloses a piezoresistive pressure sensor chip and a preparation method thereof, and belongs to the technical field of micro-electromechanical systems. The piezoresistive pressure sensor chip comprises a substrate, the back of the substrate is etched with a cavity, the center of the cavity is provided with a cross-shaped mass block, and four hollow islands and four peninsula are arranged along the linear direction of the cross-shaped mass block; a plurality of groups of piezoresistor strips are arranged on the front surface of the substrate, each group of piezoresistor strips comprises a first piezoresistor strip component arranged close to the center and a second piezoresistor strip component arranged close to the side wall of the cavity, and the first piezoresistor strip component forms an internal Wheatstone bridge through a first metal lead group; the second piezoresistor strip component forms an external Wheatstone bridge through a second metal lead group; the glass is arranged on the substrate back. The piezoresistive pressure sensor chip can measure the pressure of a micro-pressure section, can bear high overload equivalent to a plurality of times of the full scale, and has the advantages of high sensitivity, good linearity, high precision, good dynamic performance and the like.

The invention provides an MEMS pressure sensor, a manufacturing method thereof and an electronic device, and the method comprises the steps: providing a first substrate and a second substrate, forming a first pressure structure on the first substrate, and forming a second pressure structure on the second substrate; bonding the first pressure structure and the second pressure structure; the first substrate is removed, the first pressure structure and the second pressure structure jointly form a third pressure structure, the third pressure structure comprises a first electrode layer, a second electrode layer, a third electrode layer, a fourth electrode layer and a fifth electrode layer which are arranged at intervals from top to bottom, and a dielectric layer is formed between every two adjacent electrode layers; and cavities penetrating through the dielectric layers are formed in the dielectric layers. According to the scheme, the multiple electrode layers arranged from bottom to top are formed, the multiple electrode layers form the first capacitor, the second capacitor, the third capacitor and the fourth capacitor respectively, then the Wheatstone bridge is formed jointly, the measurement precision of the MEMS pressure sensor is improved, meanwhile, the plane size of the MEMS pressure sensor is reduced, and the integration level of the device is improved.

The invention discloses a torque sensor and an implementation method thereof, the torque sensor comprises a composite elastomer and a sensing strain gauge, the composite elastomer comprises an outer fixing ring, an inner fixing ring, a spoke strain beam and a Y-shaped strain beam, the outer fixing ring and the inner fixing ring are of a concentric ring structure, the spoke strain beam is radially connected with the outer fixing ring and the inner fixing ring, and the Y-shaped strain beam is connected with the outer fixing ring and the inner fixing ring. The Y-shaped strain beams are arranged between the adjacent spoke strain beams, and the sensing strain gauges are printed on the Y-shaped strain beams and are connected to form a Wheatstone bridge. The anti-interference capability of the torque sensor can be improved, and the torque sensor can be widely applied to the technical field of sensors.

The invention discloses a linear beam double-island structure high-pressure pressure sensor chip with stress holes and a preparation method. The linear beam double-island structure high-pressure pressure sensor chip comprises a supporting layer, an insulating layer and a device layer which are arranged from bottom to top, a cavity is etched on the back of the supporting layer, a sensitive film is arranged right above the cavity, and a linear beam double-island structure is arranged on the sensitive film; the edge and the center of the straight beam double-island structure are respectively provided with four piezoresistor strips, the four piezoresistor strips are connected into a semi-open-loop Wheatstone bridge through five P-type heavily-doped silicon leads, five metal point electrodes are arranged at the center of the five P-type heavily-doped silicon lead areas, sealing rings are arranged on the outer sides of the peripheries of the five metal point electrodes, and the metal point electrodes are connected with the metal point electrodes through the P-type heavily-doped silicon leads. The adjacent P-type heavily-doped silicon leads and the sealing rings are separated by fine slits; according to the invention, the pressure bearing limit is effectively improved, the high range is ensured, excellent sensitivity and linearity performance are realized, the high pressure measuring capability of dozens of to hundreds of MPa is realized, the tolerable temperature is up to 400 DEG C, and the sensor is widely applied to the fields of petroleum, natural gas, chemical engineering, high-pressure equipment monitoring and the like.

The invention relates to a piezoresistive sensor. In particular, the present disclosure relates to piezoresistive sensor elements and piezoresistive pressure sensors that detect mechanical stresses acting on a membrane. The piezoresistive sensor element (100) comprises a substrate which, in operation, is subjected to a mechanical stress in response to a measured variable to be measured, a first array of at least four sensitive varistors (114), where the sensitive varistors (114) are arranged on the substrate and connected to form a first Wheatstone bridge for generating a first bridge signal, and a second array of at least four sensitive varistors (114) arranged on the substrate and connected to form a second Wheatstone bridge for generating a second bridge signal. A second array of at least four insensitive varistors (122), where the insensitive varistors (122) are connected to form a second Wheatstone bridge for generating a second bridge signal, where the stress sensitivity of the sensitive varistors (114) is higher than the stress sensitivity of the insensitive varistors (122), and wherein an output signal of the piezoresistive sensor element (100) is generated based on a difference of the first bridge signal and the second bridge signal.

The invention relates to the technical field of sensors, and provides a six-dimensional force and torque force sensor and a preparation method thereof.The six-dimensional force sensor is of a disc-shaped structure and comprises an outer supporting ring, an inner mass block and eight elastic beams connected between the outer supporting ring and the inner mass block; wherein the eight elastic beams comprise a first elastic beam and a second elastic beam which are alternately arranged around the inner mass block, the first elastic beam is a straight beam, the second elastic beam is a special-shaped beam, and a strain gauge preset on the main surface of each elastic beam responds to the strain of the elastic beam to generate a measurement signal; and the force and / or the torque applied to the inner mass block or the outer support ring can be determined according to the measurement signal. Due to the fact that the different elastic beams are different in shape and structure, the strain gauges are preset on the elastic beams of different types and positions, and the bridging mode is set, the output of each Wheatstone bridge is only sensitive to the force or the moment of force in the changed direction and is not sensitive to the force or the moment of force applied in other directions, and the decoupling capacity of the sensor structure is improved to the maximum degree.

The invention discloses a device and a method for measuring the velocity field of an autoclave through hot-pressing wind speed. The device comprises a thermosensitive probe, a Wheatstone bridge, a lock-in amplifier, an NI multi-channel data acquisition card and a computer, the thermosensitive probe is used for instantaneously detecting the temperature of a placement point position and generating resistance fluctuation based on sensing temperature change; the Wheatstone bridge is formed by connecting a fixed resistor, a variable resistor and a thermosensitive probe, and is used for forming a series circuit with the lock-in amplifier; the lock-in amplifier is used for supplying power to the Wheatstone bridge and providing co-frequency voltage at the same time, so that resistance data of a thermosensitive probe in the Wheatstone bridge is converted into voltage data to be output; the NI multi-channel data acquisition card is used for acquiring in-phase component voltage signals output by the lock-in amplifier; the computer is used for processing the voltage data to obtain the average speed and the pulsation speed of the measurement point. According to the invention, the problems of limited precision, insufficient sensitivity and poor adaptability to the internal environment of the autoclave in the conventional gas speed measurement method are solved.

The invention relates to an integrated multi-mode tactile perception dexterous finger and a robot, and belongs to the technical field of robot sensing. Comprising a flexible printed circuit which comprises a Wheatstone bridge circuit, a switch chip, a microcontroller, a rigid sensing unit and a flexible triboelectric sensing unit electrode; the rigid sensing unit comprises a temperature and pressure sensing chip; the Wheatstone bridge circuit is connected with the switch chip, and the switch chip is connected with the microcontroller; the microcontroller is respectively connected with the sensing chip and the flexible friction electric sensing unit electrode; the dexterous finger shell comprises a first shell and a second shell; the first shell and the second shell are connected to form a containing cavity, and the flexible printed circuit is arranged in the containing cavity. And the flexible friction electric sensing unit friction layers are arranged on the surfaces of the first shell and the second shell and are connected with the rigid sensing units and the flexible friction electric sensing unit electrodes. The multi-mode touch sensing device has a multi-mode sensing function, can recognize various touch modes, adopts an integrated mode, and enhances reliability and sensing precision.

The invention discloses a temperature self-compensation Wheatstone bridge structure, and relates to the field of Wheatstone bridges, at least one group of sub-strain gauges which are separated from adjacent arms, are mutually compatible and are attached to the same area of the same elastic beam exist in a four-arm resistor of the Wheatstone bridge structure; the temperature resistance change trends of the compatible sub strain gauges tend to be the same; wherein each group of compatible two sub-strain gauges are closely attached to each other so that the two sub-strain gauges are located in the same area of the same elastic beam, so that the two closely attached sub-strain gauges generate homodromous temperature resistance variation, resistance temperature drift caused by local temperature difference of different arms is counteracted, and temperature self-compensation is realized. According to the invention, temperature compensation can be carried out on the local temperature difference of the force sensor, so that the measurement accuracy of the six-dimensional force sensor is improved.

The invention discloses a micropositioner hysteresis compensation driving control system and method based on strain gauges, and relates to the technical field of micro positioning control. The system comprises a micropositioner mechanical module, a displacement detection feedback module, a control module and a power amplifier module. In the mechanical module, a piezoelectric ceramic stack drives a moving table, and a first flexible hinge group and a second flexible hinge group are respectively used for guiding and transmitting driving force and are symmetrically arranged; the displacement detection feedback module outputs a voltage signal through a strain gauge adhered to the first flexible hinge and a Wheatstone bridge; the control module reversely deduces actual displacement according to a voltage signal and a strain-displacement linear relation, and a control signal is generated by comparing an instruction; and the power amplifier module converts the signal into a driving voltage to adjust the piezoelectric ceramic stack, so that closed-loop control is realized to suppress a hysteresis error. According to the invention, system integration is realized, cost and operation difficulty are reduced, and positioning precision and reliability are improved.

A piezoresistive sensor element is provided that detects mechanical stress acting on a membrane. The piezoresistive sensor element includes a substrate, which in operation is subjected to mechanical stress in response to a measurand to be measured, a first array of at least four sensitive piezoresistors, wherein the sensitive piezoresistors are arranged on the substrate and are connected to form a first Wheatstone bridge for generating a first bridge signal, a second array of at least four insensitive piezoresistors, wherein the insensitive piezoresistors are connected to form a second Wheatstone bridge for generating a second bridge signal, wherein the sensitive piezoresistors have a stress sensitivity which is higher than the stress sensitivity of the insensitive piezoresistors, and wherein an output signal of the piezoresistive sensor element is generated based on a difference of the first and second bridge signals.

The utility model discloses a high-precision joint torque sensor, which comprises a torque sensor flange and a PCB (printed circuit board) arranged on the torque sensor flange, and is characterized in that the torque sensor flange comprises an outer flange, an inner flange and at least one strain beam group connected with the outer flange and the inner flange; an annular hollow part is formed between the outer flange and the inner flange; each strain beam group comprises four strain beams which are arranged in the annular hollow part at equal intervals along the circumferential direction; a first strain gauge and a second strain gauge are arranged on the front face or the back face of each strain beam, and the first strain gauges and the second strain gauges on the four strain beams of each strain beam set are connected through a PCB to form a Wheatstone bridge structure. According to the utility model, the strain gauges are connected to form the Wheatstone bridge, and the torque measurement can be completed only through one AD sampling, so that the measurement is more convenient.

The invention relates to the technical field of force sensors, in particular to a strain gauge and a multi-dimensional force sensor using the strain gauge. Through the structural design of the strain gauge, the direct measurement of two times of multiplexing strain at the same position on the strain beam of the multi-dimensional force sensor is realized, and the precision and repeatability of the multi-dimensional force sensor are improved; the first measuring grid and the second measuring grid are nested, so that the influence of the temperature of a measuring point on the strain gauge is reduced, and the precision and the temperature performance of the sensor are improved; besides, the directions of the first zeroing gate and the second zeroing gate are consistent with the directions of the first measuring gate and the second measuring gate, so that the influence of the resistance change of the first zeroing gate and the second zeroing gate on the measurement of the strain gauge is reduced, and the linear precision is improved. Furthermore, the compensation of the initial zero point of the Wheatstone bridge can be realized, the compensation link of the multi-dimensional force sensor is simplified, the cost is reduced, the reliability of the multi-dimensional force sensor is improved, and the actual use requirement is met.

The invention discloses a method for eliminating bias signals during stress measurement of a piezoresistor and a CMOS chip, and belongs to the field of signal processing. According to the invention, at least one piezoresistive element in the Wheatstone bridge circuit is an adjustable resistor; if the piezoresistor generates a bias signal during stress measurement, the bias signal generated due to various conditions is eliminated by adjusting an adjustable resistor in the Wheatstone bridge circuit, so that when the pressure-sensitive chip is normally used, the measurement requirement can be met by externally connecting a microvolt-level power supply voltage and a small-range electric terminal, and the measurement precision is improved; and the power consumption of the pressure-sensitive chip is also greatly reduced by using the microvolt-level power supply voltage.

The invention relates to a high-g-value MEMS acceleration sensor chip based on an eight-beam structure. The piezoresistive MEMS high-g-value acceleration sensor with the eight-beam structure solves the problem that an existing accelerometer cannot meet the characteristics of high g value, high sensitivity and the like at the same time. The piezoresistive acceleration sensor with the eight-beam structure comprises a silicon-based frame fixed on a glass bottom plate, a cantilever beam and a mass block suspended in the center of the silicon-based frame through the cantilever beam, a piezoresistor forming a Wheatstone bridge is arranged on the cantilever beam, and the thickness of the silicon-based frame, the thickness of the cantilever beam and the thickness of the mass block are equal. The device is reasonable and simple in structure, has the characteristic requirements of good overload resistance and the like, and avoids the problem of failure in a severe impact environment; and an equal-thickness design is adopted, so that the manufacturing process is relatively simple, and the method is suitable for high-range acceleration sensors.

The invention provides a magnetic field sensor based on an amorphous wire giant magneto-impedance effect, which relates to the technical field of magnetic field testing and comprises a sensitive element module, an excitation module, a signal processing module and an anti-interference module. The sensitive element module adopts a CoFeSiB amorphous wire as a core sensitive material, an enameled wire is uniformly wound on the periphery of the amorphous wire to form an inductance coil, and the giant magneto-impedance effect of the amorphous wire is converted into a voltage signal through the inductance coil; and the excitation module is used for generating and outputting a high-frequency alternating excitation signal and loading the excitation signal to two ends of the inductance coil, so that the amorphous wire generates impedance change related to the to-be-measured magnetic field intensity under the action of high-frequency current. Through modular design and multi-technology cooperation of an amorphous wire giant magneto-impedance effect, Wheatstone bridge anti-interference, a temperature compensation algorithm, a multi-layer close winding and impedance matching technology, the performance bottlenecks of a traditional magnetic field sensor in the aspects of sensitivity, anti-interference, temperature drift control and signal transmission efficiency are broken through. And high-precision and high-reliability wide-temperature-range magnetic field detection is realized.

The invention discloses an AMR magnetoresistive sensor, and mainly solves the technical problem that the detection precision of an existing AMR sensor is easily affected by an external interference magnetic field. Each bridge arm of the Wheatstone bridge is correspondingly connected with a magnetoresistive element in series, and the angle difference of the magnetization directions of the magnetoresistive elements at the adjacent bridge arms is within the range of 180 + / -delta degrees. According to the AMR sensor, the anti-ferromagnetic layer is arranged, and the shape of the anti-ferromagnetic layer is the same as that of the magnetoresistive effect layer, so that compared with an existing AMR sensor, a tedious and complicated exposure process can be omitted, and the purpose of simplifying the process is achieved. And the magnetization directions of the magnetoresistive elements at the adjacent bridge arms in the sensor bridge circuit are basically opposite, so that adverse effects caused by an interference magnetic field can be counteracted when the external interference magnetic field exists, the sensitivity of the sensor is prevented from being greatly changed, and the magnetic field measurement accuracy of the sensor is ensured.

The invention relates to the technical field of rail transit transport vehicle detection, in particular to a method for measuring the axle temperature and the axle speed of a motor train unit, a circuit board fixing groove with an anti-reverse design is formed in a fixing shell and used for installing and fixing a circuit board assembly; two threaded mounting holes are formed in the mounting surface of the fixed shell and are used for fixing and connecting a sensor; the Rh is fixed on the side of the air guide hole through a pouring sealant, and the distances between the Rk and the Rh and the surface of the shell in the direction of the mounting gap are the same; the gear dependent measurement principle based on the Hall effect is abandoned, the temperature and resistance value change of the platinum thermistor Rh is driven through the installation gap airflow pressure intensity change caused by rotation of a measured shaft, shaft speed measurement is completed in combination with a Wheatstone bridge, and the installation position limitation and gear modulus constraint of a sensor on a metal gear are thoroughly eliminated. The installation flexibility of the sensor in the complex space layout under the motor train unit and the adaptation efficiency of different train types and shaft system structures are greatly improved.

The embodiment of the invention provides an on-load tap-changer detection method, electronic equipment and a piezoelectric sensor. The method comprises the following steps: calculating internal pressure generated by a preset piezoelectric crystal in the piezoelectric sensor; calculating a resistance change rate in a Wheatstone bridge preset in a piezoresistive semiconductor film on the upper side of the piezoelectric sensor based on the internal pressure; calculating a differential voltage signal based on the resistance change rate; current state information of the on-load tap-changer is determined according to the differential voltage signal and a preset threshold value, the state information comprises whether the on-load tap-changer is abnormal or not and a current abnormal type of the on-load tap-changer, and the preset threshold value comprises a first threshold value associated with a partial discharge state and a second threshold value associated with a vibration state; the first threshold is far greater than the second threshold. Therefore, whether the on-load tap-changer is abnormal or not can be monitored more comprehensively and efficiently, and the current abnormal state of the on-load tap-changer can be accurately determined.

The invention relates to a ceramic sensor for monitoring the internal state of a battery and a preparation method of the ceramic sensor. The ceramic sensor comprises a ceramic substrate with a cavity structure, a pressure sensitive element which is arranged in the ceramic substrate and comprises a cavity structure, and a temperature sensitive element which is arranged in a non-cavity structure area in the ceramic substrate, wherein the pressure sensitive element is a capacitive pressure sensitive element which is composed of a cavity structure, a first pressure sensitive electrode arranged on the upper surface of the cavity structure and a second pressure sensitive electrode arranged on the lower surface of the cavity structure, or the first pressure sensitive electrode and the second pressure sensitive electrode are arranged in the cavity structure. The pressure sensitive element is a piezoresistive pressure sensitive element which is composed of a cavity structure, a Wheatstone bridge and a piezoresistor, wherein the Wheatstone bridge and the piezoresistor are arranged on the inner surface of the cavity structure. The lithium battery internal state monitoring sensor overcomes the defects of an existing lithium battery internal state monitoring sensor in the aspects of high temperature resistance, corrosion resistance and high reliability, and a new scheme is provided for lithium battery internal state monitoring and similar harsh environment sensing.

An integrated plane bridge type weighing sensor comprises a sensor, an upper pressure head, a steel ball and a bottom plate, the sensor comprises an elastic body and a strain gauge, and the elastic body is an integrated piece composed of an upper bearing end, a lower fixing end and an integrated plane bridge body. An upward protruding part is arranged in the middle of the upper end face of the integrated plane bridge body and integrally connected with the middle of the lower end face of the upper bearing end to form a bearing body, and the left side and the right side of the lower end face of the integrated plane bridge body extend downwards to be integrally connected with the top face of the lower fixing end to form a supporting body. And the four strain gauges are arranged at the middle positions in the grooves and are connected with one another to form a Wheatstone bridge. The sensor is reasonable in structure and convenient to install, has good unbalance loading resistance, impact resistance and azimuth error resistance, has the advantages of a bridge type sensor, and is stable and reliable in performance, excellent in dynamic response performance, capable of self-resetting, high in adaptability and high in measurement precision.

The invention discloses a ceramic flat membrane double-sheet resistance type pressure core body, which belongs to the technical field of pressure sensing, is a flat membrane double-sheet type structure pressure sensing core body, and comprises a ceramic pressure sensing membrane, a Wheatstone bridge, a sealing layer, a ceramic base and a PIN needle, wherein the Wheatstone bridge comprises a strain resistor and a wire, is arranged on the surface of the ceramic pressure sensing diaphragm and is used for converting deformation of the ceramic pressure sensing diaphragm into a voltage signal; the sealing layer is used for sealing the ceramic pressure sensing diaphragm and the ceramic base into a whole; the PIN needle is arranged at the bottom of the ceramic base, is connected with a lead of the Wheatstone bridge and is used for outputting a voltage signal; moreover, the top of the ceramic base is provided with a deformation pit, and the two sides of the deformation pit are provided with double-lug structures. The resistance-type pressure core body is simple in structure, adopts the design of a flat-film double-piece structure, a double-lug structure, a zero-setting-free resistor and the like, and is beneficial to simplifying the production process, reducing the production and manufacturing cost and improving the anti-explosion performance and the pressure sensing sensitivity at the same time.