123 results about "Charge amplifier" patented technology

The utility model provides an environment-adaptive wind generating set vibration signal intelligent acquisition device, and belongs to the technical field of wind generating set vibration monitoring. The problems of poor sensor arrangement flexibility and poor signal transmission stability in existing wind power generation recording vibration monitoring are solved. Comprising a vibration sensor, a charge amplifier, a data acquisition module and a microprocessor which are arranged on a cabin cylinder of the wind generating set, the output end of the vibration sensor is connected with the input end of the charge amplifier, the output end of the charge amplifier is connected with the input end of the data acquisition module, and the output end of the data acquisition module is connected with the microprocessor; wherein tracks are fixed on the inner surface and the outer surface of the cabin cylinder, at least one moving trolley is arranged on the tracks, and the vibration sensors are fixed on the moving trolleys; the vibration monitoring device is applied to vibration monitoring of the wind generating set.

The invention relates to the technical field of automobile electrical detection, provides an automobile wire harness wire insulation skin damage detection method and system, and aims to solve the technical problem that a certain loop insulation skin damage position point is difficult to find in the prior art. Comprising a plane capacitance sensor used for measuring capacitance change between the plane capacitance sensor and a to-be-measured wire harness to obtain a charge signal used for representing the damage state of an insulating material of the to-be-measured wire harness; the charge amplifier is used for performing voltage conversion and amplification processing on the charge signal to obtain a voltage signal; the impedance analyzer is used for calculating impedance through the voltage signal and the current signal, drawing a Bode diagram based on the obtained impedance, and performing index parameter extraction on the Bode diagram to obtain various index parameters; and the upper computer is used for carrying out feature extraction on the multiple index parameters to obtain feature data, and analyzing the damage state of the insulating material of the wire harness to be detected according to the feature data to obtain a detection result.

The utility model discloses an IEPE circuit comprising a signal detection unit and a power supply unit, the power supply unit supplies power to the signal detection unit, the signal detection unit comprises a charge amplifier and a transient surge current suppression unit, the transient surge current suppression unit is connected with the charge amplifier in parallel, the power supply unit comprises a constant current source, and the constant current source is connected with the charge amplifier in parallel. And the constant current source supplies power to the charge amplifier. The interference suppression circuit is suitable for the IEPE sensor, can effectively suppress interference, and ensures the effectiveness of an output signal of the IEPE sensor.

A device and method for representing the foam porosity state of foamed lightweight soil with self-adjusting beams, and relates to the technical field of sound absorption coefficients measurement; the device includes a standing wave tube, a plurality of polyvinylidene fluoride piezoelectric films, a sensor, an exciter, a push-pull handle, an adjustable telescopic tube, a foamed lightweight soil detection material, a charge amplifier, a data memory, a data adapter, a signal generator, an adaptive power amplifier board, and a PC computer; the device of the invention has low cost, long service life, high measurement accuracy, relatively simple production process, and can be applied to different scenarios.

The invention discloses an experimental device and method for measuring the shear flexoelectric coefficient of a non-Newtonian fluid dielectric, and the experimental device comprises a halfpace-shaped container which is made of an insulator material, a cylindrical rotor which is located at the central axis of the interior of the container, a torque motor which is connected with the cylindrical rotor, and metal electrodes which are fixed on the upper and lower inner surfaces of the container. The charge amplifier is connected with the electrodes, the signal processing module is connected with the charge amplifier, the torque motor is used for rotating the cylindrical rotor to generate gradient velocity and strain on the non-Newtonian fluid in the container, and the non-Newtonian fluid dielectric generates shear strain gradient in the axial direction and the radial direction to generate flexoelectric effect electric polarization; polarized charges on the electrodes are sent to the charge amplifier through the electrodes and are converted into voltage signals, the voltage signals are transmitted to the signal processing module to obtain the number of charges, and the shear flexoelectric coefficient of the non-Newtonian fluid dielectric can be obtained by combining container structure parameters.

The invention provides a sleep physiological parameter real-time monitoring method based on flexible piezoelectric sensing, and relates to the technical field of biomedical signal processing.The method comprises the steps that a human body sleep biological mechanical signal is collected through a flexible piezoelectric sensor array, and after the signal is converted through a charge amplifier, phase-space reconstruction denoising and self-adaptive gain control are carried out; wherein the gain is dynamically adjusted based on the weight of the user, the rigidity coefficient of the mattress and the real-time signal amplitude; extracting heartbeat wave crest intervals, respiratory cycles and body movement frequency domain energy characteristics from the preprocessed signals; inputting the features into a cascaded convolutional neural network and a long-short-term memory network model, and synchronously outputting the heart rate, the respiration rate and the heart rate variability; in combination with the historical health data of the user and the cardiovascular health mapping model, sleep quality indexes and disease risk scores are generated through graph convolutional network analysis, and the monitoring frequency is dynamically adjusted and an apnea alarm is triggered.

The invention provides a design method of an adaptive signal conditioning system of a flexible gait sensor, and belongs to the technical field of flexible sensor signal conditioning. The method comprises the following steps: establishing a gait feature database by analyzing gait features in different states; obtaining design reference values of a gain G and a time constant according to stride frequencies and signal amplitudes of different gait states and requirements on dynamic response characteristics, and calculating corresponding accurate RC values under different gait states through mathematical relationships between the design reference values and capacitors and resistors in a charge amplifier and a low-pass filter circuit; carrying out simulation verification, and carrying out iterative optimization on the key parameters according to a result; designing a complete hardware system, and completing the design and layout of a PCB; and finally, circuit parameters are dynamically adjusted based on a pre-stored stride frequency RC mapping relation, and dynamic adaptive adjustment of the stride frequency is realized. According to the invention, high-precision conditioning output of mV-level weak signals is realized, the precision and stability of signal acquisition are remarkably improved, and the application scene of the system is expanded.

The application discloses a kind of multi-modal flexible sensor adaptive signal conditioning system design method, belong to flexible sensor signal conditioning technical field.The present application overcomes the defects of poor universality, performance compromise, high cost of mass production of existing conditioning circuit, adopts layered decoupling and dynamic reconstruction system-level architecture: through multi-modal feature analysis and demand mapping modeling, the feature vector composition of scene recognition is determined;Design configurable analog front end, integrate instrument amplifier, transimpedance amplifier, charge amplifier, bridge amplifier four parallel processing sub-modules, wherein charge and bridge amplifier adopt self-designed architecture with dynamic adaptive gain adjustment capability;Build heterogeneous digital processing platform with NPU, CPU, DSP as core, through cross-modal data fusion, scene recognition engine, dynamic hardware configuration combined with feedforward and feedback, loadable algorithm library and closed-loop optimization control law, realize the real-time scene reconstruction of hardware parameters and digital algorithm;Combined with domestic single-chip selection, rigid-flex PCB and automatic calibration, meet the demand of low-cost mass production.The present application realizes the native adaptation and performance optimization of single hardware platform to voltage, current, charge, impedance and other types of sensor signals, and can be widely applied in robot dexterous hand, medical monitoring, intelligent bandage, consumer motion monitoring and industrial monitoring fields.

The invention relates to the technical field of intelligent manufacturing, and discloses a six-component cutting force and torque dynamometer based on a piezoelectric film, the six-component cutting force and torque dynamometer comprises a bottom sealing cover and a shell, a dynamometer base and a base are arranged above the bottom sealing cover, horizontal pressing blocks higher than the base are arranged on four vertical mounting surfaces of the base, and the horizontal pressing blocks are arranged on the bottom sealing cover. The top faces of the horizontal pressing blocks support and are provided with Z-direction pressing blocks, PVDF piezoelectric films are installed between each horizontal pressing block and the vertical installation face and between each horizontal pressing block and the Z-direction pressing block in a pre-tightening mode, and the output end of each PVDF piezoelectric film is connected with an input channel of a charge amplifier. And the output end of the charge amplifier is connected with the MCU main control chip through the AD converter. By combining the layout of the multi-directional pressing block and the pre-tightening film decoupling structure, the problem of multi-component coupling interference of a traditional dynamometer is effectively solved, the dynamic force detection precision and the response speed are improved, the manufacturing cost is low, and the installation convenience is high.

The measuring probe of the present invention includes: a probe; a fulcrum accessory that supports the probe; an actuator that vibrates the probe; and a force sensor that outputs a voltage value corresponding to a reaction force acting on the actuator when the distal end of the probe is brought into contact with the auditory ossicles. The actuator applies vibration of a constant amplitude centered on a fulcrum near the center of gravity of the probe. The force sensor includes a piezoelectric sensor and a charge amplifier. The piezoelectric sensor converts the reaction force of the force applied by the actuator from the probe to the auditory ossicles into a charge signal. The charge amplifier converts the charge signal into a voltage and outputs the voltage. The measuring probe includes a rigidity / inertial force applying mechanism that applies to the measuring probe rigidity capable of maintaining a constant relative position between the fulcrum and the actuator and an inertial force capable of overcoming the vibration of the actuator.

The present invention discloses a multi-gain flat-panel detector and a reading data processing method, belonging to the field of image processing. The multi-gain flat-panel detector includes a scintillator layer and a reading circuit layer. Before reading, the reading circuit layer detects and corrects the signal and then outputs the image. Each pixel of the read image corresponds to its own independent thin-film transistor array, control circuit, and analog-to-digital converter, thereby achieving independent pixel reading. In addition, the overall capacitance of the charge amplifier can be adjusted by software control of the switching of the circuit containing the individual capacitors in the charge amplifier, thereby achieving control of the reading gain, solving the problems of data saturation and low data signal-to-noise ratio that are prone to occur in flat-panel detectors.

The present invention discloses a critical pressure testing system and method for detecting the entry of explosive combustion flames into gaps. The system comprises a main reaction device, a pressure testing unit, an ignition unit, and a photographic unit. The main reaction device comprises a reaction cell, a viewing window, and a gland. The pressure testing unit comprises a pressure sensor, a charge amplifier, and an oscilloscope. The ignition unit comprises an igniter, an optical fiber, and a laser. The photographic unit comprises a high-speed camera and a data collector. The testing unit also comprises a synchronous signal trigger for controlling the pressure testing unit and the photographic unit. The pressure testing unit and the ignition unit are both connected to the main reaction device, the photographic unit is connected to the synchronous signal trigger, and the pressure testing unit and the ignition unit are each connected to the synchronous signal trigger. The system and method provide a new option for distinguishing the safety of explosives with different formulas and can more accurately determine the relative accident risks of explosives with different formulas or storage periods.

The invention discloses a non-Newtonian fluid high-precision ion concentration measurement system and method based on a liquid flexoelectric effect, and the measurement device comprises a halfpace-shaped container, a cylindrical rotor located at the central axis in the container, a torque motor connected with the cylindrical rotor, metal electrodes fixed on the upper and lower inner surfaces of the container, and a charge amplifier connected with the electrodes. The signal processing module is connected with the charge amplifier, a torque motor is used for rotating the cylindrical rotor to generate gradient velocity and strain on the liquid in the container, and the liquid generates shear strain gradient in the axial direction and the radial direction to generate flexoelectric effect electric polarization; ions in the solution gather on the electrode to form a double-electric-layer effect to partially shield flexoelectric polarization. Polarized charges on the electrodes pass through the charge amplifier and are converted into voltage signals, the voltage signals are transmitted to the signal processing module, and the ion concentration of the solution can be obtained after material parameters of the solution and container structure parameters are combined. In addition, the method can also be used for measuring the concentration of various ions contained in the non-Newtonian fluid under specific conditions.

The invention discloses a solid attitude and orbit control engine thrust vector in-situ calibration device and calibration method. The device is characterized by comprising a rack, a gantry type calibration frame, a standard force source mechanism and a force measuring system, the gantry type calibration frame is fixed above the rack, the standard force source mechanism is fixed on the gantry type calibration frame, and the force measuring system is arranged below the gantry type calibration frame and fixed on the rack; the standard force source mechanism comprises a transverse force generating unit and a vertical force generating unit; the force measuring system comprises a piezoelectric force measuring table, an adapter plate and a solid attitude and orbit control simulation engine, the piezoelectric force measuring table is fixed on the rack, and the solid attitude and orbit control simulation engine is mechanically positioned on the piezoelectric force measuring table through the adapter plate. The structure is simple, the loading position is flexibly adjusted, the influence of the zero drift of the piezoelectric sensor and the charge amplifier on the calibration precision is effectively reduced, and the thrust vector test precision of the solid attitude and orbit control engine is further improved.

Methods and apparatus for measuring current are provided. In one arrangement, a first charge amplifier integrates the current to be measured. A processing circuit filters the output from the first charge amplifier using a first low-pass filter module and a second low-pass filter module. A second charge amplifier integrates the current resulting from the filtered output from the first charge amplifier. The apparatus is configured to reset the first charge amplifier at the start of each sensing frame among a plurality of sensing frames. The processing circuit obtains at least a first sample of the output from the first charge amplifier within each sensing frame. Sampling of the first sample alternates between sampling through the first low-pass filter module and sampling through the second low-pass filter module from one sensing frame to the next.

The present invention discloses an anti-high-frequency large-signal two-wire charge amplification circuit and its implementation method, which includes a charge-to-voltage conversion circuit, a low-pass filter circuit, an AC amplification circuit, and a power supply processing circuit; the low-pass filter circuit is a sixth-order low-pass filter circuit, the output end of the charge-to-voltage conversion circuit is connected to the low-pass filter circuit, the low-pass filter circuit is connected to the AC amplification circuit, and the AC amplification circuit is connected to the power supply processing circuit. By adopting a constant current source two-wire power supply to reduce the wiring harness, the front-stage charge-to-voltage conversion circuit uses a circuit with a field-effect transistor as the core to convert and attenuate the signal, so as to reduce the requirements for the electrical performance indicators of the operational amplifier in the subsequent signal processing circuit, and adopts a signal link based on signal attenuation, low-pass filtering, signal amplification, and power supply processing to achieve the suppression of high-frequency large signals under the condition of ensuring the amplitude-frequency characteristics of the required working frequency band, and ensure that the signal is not clipped and distorted and deeply saturated.

The invention relates to the technical field of pipeline sealing monitoring, and relates to a signal conditioning circuit and a water supply pipe network leakage monitoring system, the signal conditioning circuit comprises an impedance matching module, a first charge amplifier and a frequency clamping module which are connected in sequence; the impedance matching module is in communication connection with a sensor used for collecting acoustic vibration signals of the water supply network; the input end of the impedance matching module is used for receiving an acoustic vibration signal; the frequency clamping module is used for limiting the amplitude of an interference sound wave signal; the interference sound wave signal is a sound wave signal beyond a frequency range corresponding to the acoustic vibration signal sent by a water supply network; according to the invention, acoustic vibration signals collected by the sensor can be filtered, amplified and subjected to frequency limiting processing, and the influence of interference acoustic signals on a water supply network leakage detection result is reduced.

A mass spectrometer can have an ion source region including an ion generator configured to generate ions from a sample, an ion detector configured to detect ions and generate a corresponding ion detection signal, a field-free drift region disposed between the ion source region and the ion detector through which the generated ions axially drift towards the ion detector, a plurality of spaced-apart charge detection cylinders through which the ions that are axially drifting through the drift region pass, and a plurality of charge amplifiers, each charge amplifier being coupled to a different one of the plurality of charge detection cylinders and each being configured to generate a charge detection signal that corresponds to the magnitude of the charge of one or more of the generated ions passing through the corresponding one of the plurality of charge detection cylinders.

The present invention discloses a smart pipe network fault detection method and system based on flexible sensing materials, which belongs to the field of fault detection technology. The key points of its technical solution include: determining multiple charge amplifiers currently transmitting electrical signals, and the time when multiple charge amplifiers transmit each electrical signal; determining the flexible sensor corresponding to each charge amplifier in the multiple charge amplifiers, and the preset delay duration corresponding to the flexible sensor; determining the flexible sensor that generates charge based on the time of collecting each electrical signal and the preset delay duration; determining the fault location of the smart pipe network based on the location of the flexible sensor that generates charge. When there are multiple flexible sensors, the present invention reduces the number of charge amplifiers used, and at the same time, through the setting of the delay module, accurately identifies the flexible sensing material corresponding to each signal transmitted by the charge amplifier, and finally determines the fault location of the smart pipe network through signal analysis.

The application provides an impact acceleration measurement method based on an impact acceleration measurement device, which comprises an impact wave generating device, a piezoelectric pressure sensor, a test block, a charge amplifier, a dynamic signal test collector, a microcomputer and a MATLAB simulation environment, and the measurement method comprises the following steps: step 1, determining the measurement point position of the measured equipment, and selecting the piezoelectric pressure sensor and the test block to be installed; step 2, applying impact charge to the measured equipment by using the impact wave generating device, testing, and collecting force signals; and step 3, calculating the time-domain acceleration according to the collected force signals, so that the application has the advantages of providing a device with simple structure, convenient operation and accurate impact acceleration measurement, and providing a measurement impact acceleration method with the advantages of eliminating low-frequency zero drift, not being controlled by frequency size and high testing precision.

The present invention discloses a piezoelectric pressure sensor based on an In2Se3 / InSe vertical heterojunction, and its preparation method and application, belonging to the technical field of sensor instrument construction. The present invention uses an In2Se3 / InSe vertical heterojunction thin film as a pressure-sensitive layer to prepare a piezoelectric pressure sensor. The stress change caused by the air pressure will change the energy band structure of the In2Se3 / InSe vertical heterojunction, thereby generating a piezoelectric voltage. This change can be monitored by detecting its voltage change through a charge amplifier, thereby achieving a highly sensitive response to tiny air pressure changes. The piezoelectric pressure sensor of the present invention is small in size and highly sensitive, providing a simple, sensitive and stable device and detection method for high-precision air pressure detection.

The invention relates to offset voltage cancellation for charge amplification circuits. A circuit includes an amplifier, a bias node, and a first set of switches configured to couple an amplifier input node to the bias node and a short-circuited amplifier output node based on an asserted first reset signal. Each of the first and second feedback branches includes a respective circuit network including a shunt capacitor, the first capacitor being directly connected to the amplifier input node. The first and second feedback branches further include a second set of switches intermediate the amplifier input node and the second capacitor, and a third set of switches intermediate the amplifier output node and the capacitor. The switches selectively couple the capacitors to the amplifier input and output nodes based on the asserted second reset signal. The time interval in which the second reset signal is asserted exceeds the time interval in which the first reset signal is asserted.

The utility model belongs to the technical field of charge signal processing, and particularly relates to a multiple-adjustable charge amplifier circuit, which comprises a low-pass filter circuit, an integral negative feedback amplification circuit, a high-pass filter circuit, a voltage amplification circuit and a double-T-shaped wave trap circuit, wherein the low-pass filter circuit is used for filtering a high-frequency signal of a charge signal; the integral negative feedback amplification circuit is used for converting the charge signal into a charge voltage signal; the high-pass filter circuit is used for filtering low-frequency signals; the voltage amplifying circuit is used for amplifying the charge voltage signal; the double-T-shaped wave trap circuit is used for filtering power frequency interference. The charge amplifier solves the problems that the amplification factor of the charge amplifier is adjustable, the impedance of the charge amplifier is large, and the charge amplifier is easily interfered by power frequency radiation or other noises.

The invention discloses a signal acquisition module based on adaptive polar zero cancellation. A signal processing unit comprises a digital polar zero cancellation module with Kalman filtering and a filtering forming module with template matching; the digital pole zero cancellation module with Kalman filtering is used for solving the problem of digital pole zero cancellation digital coefficient mismatch caused by temperature excursion of the front-end analog charge amplifier module, and the problem of digital pole zero cancellation digital coefficient mismatch refers to voltage overcompensation and voltage undercompensation caused by suppression of pole zero point mismatch; the filter forming module with template matching is used for solving the problem of waveform accumulation in digital filter forming after digital pole zero cancellation. Based on the self-adaptive pole-zero cancellation signal acquisition module, key technologies such as Kalman filtering and template matching are fused, the limitations of traditional nuclear pulse digital processing in the aspects of temperature drift adaptability, anti-accumulation performance, time extraction precision and the like are effectively overcome, and the comprehensive performance of the system is remarkably improved.

The invention discloses a composite heat balance piezoelectric deformation reflector and a processing technology thereof, and belongs to the field of optical devices, the composite heat balance piezoelectric deformation reflector comprises a mirror surface substrate layer, the center of the mirror surface substrate layer is provided with an analysis aperture area, and the front surface of the mirror surface substrate layer is provided with an annular heat balance layer; and a mirror surface multi-degree-of-freedom control electrode array for realizing high-order optical modal actuation and a mirror surface structure modal reconstruction electrode array for realizing low-order mirror surface structure modal sensing are sequentially arranged on the back surface of the mirror surface substrate layer from inside to outside. According to the composite heat balance piezoelectric deformable mirror and the processing technology thereof, the front and back surfaces of the mirror surface substrate layer are covered with different materials, so that complete heat balance of the deformable mirror structure can be realized, namely extremely small deformation in an aperture is effectively analyzed under the condition of temperature change, and the heat stability of the structure is ensured; and meanwhile, by additionally arranging the auxiliary electrode and the multi-channel charge amplifier array, modal sensing of relative surface shape change can be realized.

The invention relates to the field of charge amplifiers, in particular to a multi-gear multi-channel charge amplification device for a differential three-dimensional force detection mechanism. A multi-gear multi-channel charge amplification device for a differential three-dimensional force detection mechanism comprises a charge amplifier integrated circuit board electrically connected with the differential three-dimensional force detection mechanism, and the charge amplifier integrated circuit board is provided with a charge signal input interface, a power supply interface and at least three multi-gear charge amplifier units. The multi-gear charge amplifier unit comprises a precision operational amplifier chip and n adjustable amplification gears, and the on-off states of n feedback capacitors are switched through a 2n-bit patch dial switch to achieve gear switching. The method has the advantage of being higher in universality, can be used for cutting machining of various products, meets the requirements of different measurement ranges, and does not need to additionally add signal debugging equipment.

According to one embodiment, a sensor includes an element section and a circuit section. The element section includes a base including a base face, a fixed portion fixed to the base face, a movable portion supported by the fixed portion, a first gap being provided between the base face and the movable portion, and a plurality of fixed electrodes fixed to the base face and facing the movable portion. The plurality of fixed electrodes includes a first electrode and a second electrode. A first direction from the fixed portion to the first electrode is along a first plane along the base face. A second direction from the fixed portion to the second electrode is along the first plane and is inclined with respect to the first direction. The circuit section includes a first charge amplifier and a second charge amplifier.

A capacitive sensing charge amplifier, e.g., in a direct current (DC) feedback network, may incorporate a switching capacitor, including a first control switch and a second control switch, which receives a switching signal to charge and discharges the switching signal to a virtual ground of a sense amplifier. Noise incorporated into the output of the sense amplifier (e.g., a MEMS output signal) is filtered by a demodulation signal at a demodulator such that the period average noise at the demodulator output equals zero. The time varying nature of the switching capacitor resistance generally reshapes the system's post-demodulation noise to reduce its low frequency output noise.

The application provides a MEMS gyroscope, which comprises a MEMS inertial sensing part, a gyroscope interface circuit, wherein the MEMS inertial sensing part comprises a driving capacitor group, a driving detection capacitor group and a detection capacitor group of one or more axes; the gyroscope interface circuit comprises a driving circuit, a detection circuit of one or more axes, a correction capacitor group of one or more axes and a digital processing circuit; the driving circuit comprises a driving charge amplifier, the detection circuit comprises a detection charge amplifier of one or more axes, one end of a first correction capacitor in the correction capacitor group of each axis is connected to a first output end of the driving charge amplifier, the other end is connected to a first input end of the detection charge amplifier of the corresponding axis, one end of a second correction capacitor in the correction capacitor group of each axis is connected to a second output end of the driving charge amplifier, and the other end is connected to a second input end of the detection charge amplifier of the corresponding axis. In this way, the quadrature error can be eliminated, and the gyroscope zero bias stability and noise level are improved.

The embodiment of the present application relates to a kind of single-ended conversion differential capacitor sampling compensation device and sampling compensation method, the device includes: compensation module, at least including one compensation capacitor;The compensation module is connected with the capacitor to be measured, for compensating the reference value of the capacitor to be measured;Sampling amplification module, at least including one charge amplifier and feedback capacitor;The sampling amplification module is connected with the capacitor to be measured and compensation module, for converting the capacitance value of the capacitor to be measured into differential voltage value output, to obtain the capacitance value of the capacitor to be measured.The technical scheme of the embodiment of the present application realizes the operation of single-ended conversion differential with one single-ended circuit.Due to the fact that a pseudo branch can be saved, this structure reduces the area of chip when applied in the scenario of large measured capacitor;And due to the innovation of sampling mode between different working phases, it is realized that the standard value of large measured capacitor can be offset with smaller compensation capacitor.