62 results about "Zero bias" patented technology

The invention provides a current sampling zero offset correction method and device. The current sampling zero-bias correction method comprises the following steps: determining a correction trigger opportunity, wherein the correction trigger opportunity is a moment when an output voltage vector of a power converter is in a zero vector state and a theoretical value of current flowing through a current sampling resistor is zero; sampling a current sampling channel through an analog-to-digital converter at a correction triggering time, and obtaining original sampling data under a zero current condition; processing the original sampling data to obtain a current zero current bias value and updating the stored current bias data variable; a corrected current value is determined based on the updated current bias data variable. By setting the specific correction triggering time and correction mechanism, the current sampling zero bias can be dynamically tracked and corrected online, automatically and in real time in the whole operation process of the driver, adverse effects caused by static deviation and dynamic temperature excursion are overcome, and the control precision and robustness of the system under all working conditions are improved.

A LiGa-based 0.5 In 0.5 A self-driven X-ray detector based on Se2 crystal and its fabrication method. This detector employs an MSM device structure with c-plane LiGa... 0.5 In 0.5 Using Se2 wafers as semiconductor materials and metal materials as electrodes, self-driven X-ray detection can be achieved under zero bias voltage; the above-mentioned self-driven X-ray detector fabrication method includes the following steps: (1) fabricating LiGa 0.5 In 0.5 (1) Se2 crystal; (2) Directional processing of c-plane LiGa 0.5 In 0.5 Se2 wafer; (3) LiGa 0.5 In 0.5 The upper and lower surfaces of the Se2 wafer are polished and passivated; (4) in LiGa 0.5 In 0.5 Metal electrodes are deposited on the upper and lower surfaces of a Se2 wafer. This invention utilizes LiGa... 0.5 In 0.5 The bulk photovoltaic effect generated by the non-centrosymmetric structure of Se2 enabled the fabrication of a self-driven X-ray detector with a simple structure. Furthermore, due to the LiGa... 0.5 In 0.5 Se2 crystals have high resistivity, and the devices fabricated from them have low dark current, enabling highly sensitive X-ray detection.

The invention discloses a width gradient tungsten disulfide nanobelt, a preparation method thereof and an application of the width gradient tungsten disulfide nanobelt in a self-driven photoelectric detector, a Ni film is deposited on a substrate and is annealed to form catalytic particles, and a chemical vapor deposition system is utilized to accurately control the temperature gradient between tungsten trioxide in a central temperature zone and a growth substrate in a downstream temperature zone, so that the width gradient tungsten disulfide nanobelt is obtained. And the solid sulfur source is propelled at a constant rate, the dynamic change of the sulfur / tungsten atomic ratio in the reaction environment is regulated and controlled, and a growth mode is guided to be converted from a gas-liquid-solid mechanism to a gas-solid mechanism, so that controllable preparation of the tungsten disulfide nanobelt with the width continuously and progressively decreased in the axial direction is realized. The width of the nanobelt gradually changes from 150-500 nm to 50-120 nm, the length of the nanobelt reaches 3-12 [mu] m, and the nanobelt has an armchair edge and a 3R phase stacking structure. A self-driven photoelectric detector constructed based on the nanobelt realizes high-sensitivity detection of 532 nm laser under zero bias voltage, the responsivity reaches 5.04 A / W, the detectivity reaches 3.23 * 10 < 12 > Jones, and the nanobelt shows important application value in the fields of optical signal detection, optical switches and wireless optical communication.

The invention discloses an atomic magnetometer longitudinal magnetic field interference resisting method and system based on zero offset point control, and the method comprises the steps: building a system response model containing a zero offset error, and respectively setting the zero offset points of first harmonic and second harmonic response signals as closed-loop control targets of x-axis and y-axis magnetic fields; and the output response of the double-loop closed-loop feedback control system is stabilized at a zero offset point, so that the interference of longitudinal magnetic field fluctuation on transverse magnetic field measurement is isolated in principle, and the real-time decoupling measurement of the transverse magnetic field to be measured is realized. The problem that quasi-static and dynamic longitudinal magnetic field interference cannot be suppressed at the same time in the prior art is solved, and the device has the advantages of being completely free of longitudinal magnetic field interference, biaxial decoupling measurement and long-term stable work.

This invention discloses a high-performance tin-based perovskite photodetector, its fabrication method, and its application in covert optical information transmission. The photodetector sequentially comprises a conductive substrate, an electron transport layer, a tin-based perovskite layer, a hole transport layer, and a metal electrode layer. The tin-based perovskite layer is FASnI3, and 1,4-butanediamine hydroiodate is introduced as a molecular additive to suppress Sn. 2+ Oxidation and reduction of defect state density optimize film quality. Based on this, FASnI3 perovskite films with an inverse opal structure were successfully prepared. The slow photon effect significantly enhances perovskite light absorption and promotes carrier transport, and the "lotus leaf effect" introduced by the photonic crystal significantly improves the stability of Sn-based perovskites. The photodetector prepared by this invention achieves highly sensitive, self-powered near-infrared detection under zero bias conditions, exhibiting high responsivity, high detectivity, low dark current, and excellent stability. It can be used in optical communication, information transmission, sensing, and security optoelectronic systems.

The invention discloses a noise component calculation method and device of a hemispherical resonator gyroscope. The method comprises the following steps: acquiring a test result of the zero-bias stability of the hemispherical resonator gyroscope; carrying out ALLAN variance analysis on the test result of the zero bias stability, and determining a quantization noise coefficient, an angle random walk coefficient, a zero bias instability coefficient, a rate random walk coefficient and a rate slope noise coefficient; and calculating and determining a quantization noise component, an angle random walk noise component, a zero offset instability noise component, a rate random walk noise component and a rate slope noise component according to the quantization noise coefficient, the angle random walk coefficient, the zero offset instability coefficient, the rate random walk coefficient and the rate slope noise coefficient. According to the method, contributions of different noise components in the zero offset error source of the hemispherical resonator gyroscope can be obtained, and the long-term stability and the measurement precision of the hemispherical resonator gyroscope are improved.

This invention relates to a method for amplifying the polarization ratio of a photodetector based on a two-dimensional semi-metallic material and a heterostructure, belonging to the field of photodetection technology. Based on a strategy combining a two-dimensional semi-metallic material and a heterostructure, a BP / MoS2 / WTe2 heterojunction is constructed, where BP is the light-absorbing layer, MoS2 is the barrier layer, and WTe2 is the contact layer. This invention not only achieves selective carrier transport and reduces dark current, but also allows WTe2 to reduce contact resistance and provide a fast carrier extraction channel, realizing asymmetric amplification of the photocurrent, thereby achieving active amplification of the polarization ratio even at zero bias. This invention breaks the limitation of the inherent anisotropy of materials on the magnitude of the polarization ratio, and uses a completely dry transfer process to fabricate polarization detection photodetectors, eliminating the need for additional polarization elements and chemical solution treatment. It boasts advantages such as simple process, low cost, high repeatability, and no pollution.

This application discloses a method and related equipment for zero-bias and amplitude calibration of a signal. The method is applied to an adaptive notch filter equipped with a low-pass filter, and includes: real-time acquisition of the signal to be measured corresponding to the rotor position detection; normalization processing of the signal to be measured to obtain a first signal; inputting the first signal into a phase-locked loop for angle tracking processing to obtain a second signal; inputting the first signal and the second signal into the adaptive notch filter to calculate the amplitude of the signal to be measured; acquiring the output signal of the low-pass filter in the adaptive notch filter, and obtaining the zero-bias value of the signal to be measured based on the output signal. This application achieves low computational cost and low storage space extraction of signal amplitude and zero-bias by adding a low-pass filter to the adaptive notch filter to filter out DC signals, while reducing the impact of noise and improving the accuracy of the results.

The invention discloses a two-dimensional ferroelectric vertical heterojunction self-powered X-ray synapse transistor and a manufacturing method thereof, and belongs to the field of X-ray synapse transistors, the two-dimensional ferroelectric vertical heterojunction self-powered X-ray synapse transistor comprises a substrate, the substrate is provided with a bottom layer, a ferroelectric functional layer and a top layer which are stacked in sequence, the bottom layer is connected with a first electrode, and the top layer is connected with a second electrode. The bottom layer and the top layer are independently made of a two-dimensional semi-metal material, the ferroelectric functional layer comprises a two-dimensional ferroelectric material, the bottom layer is not in contact with the top layer, and the work function of the bottom layer is not equal to that of the top layer. According to the invention, a built-in electric field induced by ferroelectric polarization is combined, self-powered X-ray detection under zero bias voltage is realized, synaptic enhancement or inhibition can be realized through bias voltage regulation and control if X-ray pulse is taken as a stimulation signal, and short-term or long-term synaptic plasticity can be simulated. The device is simple in preparation process and excellent in stability, can be widely applied to the fields of medical diagnosis, security check screening, radiation monitoring and intelligent sensing, and provides core technical support for a'detection-synapse 'integrated device.

The carrier concentration of the drift region (87) is controlled in the semiconductor substrate in response to a voltage applied to the gate electrode (81) of the gate-controlled diode (203). In the reverse recovery state, a voltage signal of zero bias or positive bias that causes an electron layer at the interface of the gate electrode (81) is applied between the gate electrode (81) and the anode electrode (86). In the forward recovery state, a voltage signal of negative bias that causes a hole layer at the interface of the gate electrode (81) is applied between the gate electrode (81) and the anode electrode (86). After the forward recovery state, the voltage signal of zero bias or positive bias is switched from the negative bias. The gate-controlled diode (203) variably controls the period during which the voltage signal of zero bias or positive bias is applied in accordance with the non-conduction period of the IGBT connected in series therewith.

This invention relates to the field of photoelectric detection technology, specifically to a diamond immersion detector. The invention utilizes ultra-wide bandgap boron-doped p-type diamond single crystal (PDSC) as the photoelectrode to construct a vacuum ultraviolet immersion photodetector with a PDSC-ultrapure water-Pt structure. The PDSC immersion photodetector prepared by this invention exhibits a responsivity as high as 87.8 mA / W under zero bias and 193 nm excitation wavelength conditions, which is close to the photoresponsivity shown by standard commercial Si detectors; furthermore, under low optical power excitation, the responsivity of the PDSC immersion detector can reach as high as 670 mA / W. The immersion detector of this invention is a low-cost, self-powered, and highly sensitive vacuum ultraviolet photodetector with good stability, showing promising application prospects for 193 nm power monitoring in deep ultraviolet light source lithography machines.

The application provides a piezoelectric driving self-biased very low frequency mechanical transmitting antenna and a preparation method thereof. The preparation method comprises the following steps: step one, preparing piezoelectric ceramic material; step two, cutting and slotting; step three, pouring resin; step four, cutting layer sheet; step five, packaging; step six, polarization treatment; step seven, preparing adhesive layer; and step eight, hot-pressing compounding. Compared with the existing magnetoelectric antenna, the self-biased very low frequency mechanical transmitting antenna has the characteristics of self-bias, high piezoelectricity, miniaturization, no additional noise source and electromagnetic interference, and the like, has the advantages of high stress transmission efficiency and small ohmic loss, can realize the miniaturization requirement of the magnetoelectric mechanical antenna, is easy to form a large-scale array, improves the magnetic transmitting performance under zero bias, and achieves the low frequency communication effect.

According to the technical scheme provided by the invention, a structure combining an elliptical annular structure and a comb tooth structure is provided to form a lever effect to amplify the displacement of a sensitive mode, a parasitic mode between a driving mode and the sensitive mode is eliminated, and meanwhile, the long-term and short-term zero-bias stability of the gyroscope is improved; according to the technical scheme, the symmetrical large-area sensitive mass blocks are adopted, the advantage of decoupling of a driving mode and a detection mode is achieved, and meanwhile large signal output gain is achieved; the sensitive mass block and the detection frame which are symmetrical are adopted, differential detection can be achieved, the same external interference is differentiated, and the sensitivity and the anti-interference capacity are further guaranteed; and the symmetrical structure can effectively restrain machining errors, so that the stability of the gyroscope is improved.

The application belongs to the technical field of functional crystal materials, and more particularly relates to a high-stability two-dimensional Dion-Jacobson type non-lead polar hybrid perovskite crystal and a preparation method and application thereof. The high-stability two-dimensional Dion-Jacobson type non-lead polar hybrid perovskite crystal has a chemical formula of (4AMPY)2AgBiBr8, belongs to a monoclinic system, and has a space group of P21. The crystal is prepared into an X-ray detector, which can realize efficient and stable X-ray detection under zero bias voltage and high bias voltage. The single crystal is irradiated by different X-ray irradiation doses, and the X-ray response performance thereof is tested. When the crystal is irradiated by different X-ray irradiation doses, the crystal exhibits obvious light response, and the result shows that the material has potential application value as an X-ray detection material.

The invention discloses a position-sensitive Te nanowire photoelectric detector and a preparation method and application thereof, and belongs to the technical field of photoelectric detection and neuromorphic calculation. The invention discloses a suspended Te nanowire to minimize parasitic interference of a substrate so as to improve the collection efficiency of photon-generated carriers, and also can realize rapid thermal isolation to accurately control the temperature gradient so as to realize the photoelectric response of a wide spectrum at 1310-1650nm under a zero offset value. The position-adjustable positive and negative photoconductive characteristics generated by the Seebeck effect are utilized to show the calculation application of the device in the sensing under the zero offset value, 85% of accuracy is realized in the image identification application, and the problems that the calculation power consumption in the traditional sensing is large, the device separation degree is poor, the application in the communication wave band is difficult to realize and the like are solved. The device provides a thought for developing a low-power-consumption visual sensing system under wide spectrum response.

The application belongs to the technical field of photoelectric detectors, and discloses a preparation method of t-Se / Si and BP / t-Se / Si heterojunction photodetectors. First, a few-layer black phosphorus nanosheet dispersion liquid is prepared, then a trigonal selenium film is deposited on a silicon substrate to construct a t-Se / Si composite structure, and then black phosphorus nanosheets are spin-coated to form a BP / t-Se / Si heterojunction. Electrodes are prepared on the two structures respectively to obtain t-Se / Si and BP / t-Se / Si unit detectors with significantly different photoelectric response characteristics. The two units are arranged and integrated according to a preset pattern to form a patterned detector array. The array has wide spectral response and low dark current characteristics under zero bias, and can be used for non-contact displacement monitoring of precision instruments.

This invention discloses a gallium nitride Schottky diode with a quasi-depletion layer, the structure of which, from bottom to top, comprises: a substrate layer, a buffer layer, and an N-type diode. + -GaN contact layer, N ‑ -GaN drift layer, quasi-depletion layer, and anode Schottky contact layer disposed on the quasi-depletion layer and disposed on N + A cathode ohmic contact layer above a GaN contact layer; wherein the doping concentration and thickness of the quasi-depletion layer must satisfy the following: the thickness of the quasi-depletion layer is less than the width of the depletion layer of the diode at zero bias voltage. This invention significantly reduces the turn-on voltage of the diode by setting a highly doped quasi-depletion layer on the surface of the drift layer. With the combination of doping concentration and quasi-depletion layer thickness, the quasi-depletion layer is in a fully depleted state under zero bias voltage, while under reverse bias voltage, based on the characteristic that the quasi-depletion layer is already depleted at zero bias voltage, the reverse voltage is mainly due to the N-type cathode ohmic contact layer below. ‑ The GaN drift layer effectively reduces reverse leakage current.

The invention relates to the technical field of biomedical sensing and wearable health monitoring, and discloses a photoelectrochemical sensing microneedle, a preparation method thereof, a monitoring system and a detection method. The sensing microneedle comprises a swellable dual-network hydrogel microneedle substrate, a three-dimensional conductive network and a semiconductor nanostructure, wherein the three-dimensional conductive network is composed of high-length-diameter-ratio metal nanowires with a local surface plasma resonance effect, and the semiconductor nanostructure is compounded on the surfaces of the metal nanowires and forms a Schottky heterojunction. The mechanical constraint of the rigid polymer skeleton and the high length-diameter ratio of the metal nanowire cooperate to ensure the continuity of the conductive network in a swelling state. Under the irradiation of exciting light, hot electrons are migrated to the surface of a semiconductor through a Schottky junction built-in electric field to generate reactive oxygen free radicals, non-enzymatic catalytic oxidation is carried out on a target analyte in interstitial fluid under zero bias voltage or low bias voltage, a photocurrent signal is generated, and integration of minimally invasive sampling and in-situ high-selectivity detection is realized.

The invention discloses a reading head front end and a signal conditioning circuit. The reading head front end comprises a reading head front end circuit, the signal conditioning circuit and a connecting cable. Wherein the reading head front-end circuit comprises a photodiode front-end photoelectric conversion circuit and a light-emitting diode constant current source for power supply. The signal conditioning circuit comprises a quadrature phase calibration part and an FPGA digital signal processing part. A rear-end signal conditioning module completes quadrature signal zero adjustment, non-quadrature adjustment, amplitude adjustment output, zero bias automatic adjustment and phase detection functions. A photoelectric conversion circuit at the front end of a photodiode is realized through trans-impedance amplification with wide bandwidth and high gain, and acquisition of optical signals of a reading head is completed; a high-precision and high-stability constant current source power supply circuit is designed to realize high-quality output of a light source; the orthogonal phase calibration circuit can realize manual signal amplitude gain, phase adjustment range selection and phase orthogonality calibration; the FPGA digital signal processing part realizes automatic calibration of a bias level through high-speed ADC sampling and high-precision DAC output level, an FPGA obtains output signal phase information through amplitude phase discrimination, and a rear-end processing board is small in size and is integrated to a DB15 cable plug; and the connecting cable adopts a 12-core high-flexibility double-layer shielding bending-resistant cable, so that the integrity of signal transmission is ensured.

This invention relates to a method, apparatus, and device for zero-bias compensation of microelectromechanical gyroscopes (MEMS) based on temperature control, and pertains to the field of inertial sensor technology. The method includes: placing a heating chip on the back of the MEMS chip and constructing a chip-level temperature control system; adjusting the temperature to a preset desired temperature and maintaining a constant temperature state using the driving frequency as the controlled variable; collecting zero-bias output data, driving force data, and driving frequency data of the MEMS chip under constant temperature conditions as a sample set to calculate a final bivariate cubic fitting model; continuously maintaining the constant temperature state of the MEMS chip and collecting real-time driving force and driving frequency under the current operating state; then substituting these values ​​into the final bivariate cubic fitting model to calculate the zero-bias compensation value; and finally subtracting the zero-bias compensation value from the current zero-bias output result of the MEMS chip to complete the zero-bias compensation. This invention effectively suppresses the influence of temperature and operating parameters on zero-bias, improving the measurement accuracy and stability of the MEMS gyroscope.

The present application relates to a kind of system level calibration method for correcting the zero offset of acceleration channel of inertial measuring device, belongs to the field of inertial measurement.The zero position error of acceleration channel is compensated, the method does not need to disassemble inertial measuring device, by the vertical direction of three axes of aircraft respectively, the zero position error of acceleration channel of inertial measuring device can be calculated.The present application proposes the system level calibration method for quickly correcting the zero offset of acceleration channel of inertial measuring device, by simple calibration path setting, the zero offset error of acceleration channel can be effectively calculated.When the change of accelerometer itself zero offset error occurs, it is no longer necessary to disassemble inertial measuring device from aircraft and re-performs discrete calibration, and the influence of installation error caused by repeated installation of inertial measuring device is avoided.

The application discloses a multi-frequency excitation method for improving the performance of a MEMS resonant electric field sensor, and belongs to the technical field of electric field sensors. The method comprises the following steps: performing modal analysis on the sensor, extracting the vibration mode information of each order mode, and designing an excitation scheme for each order mode; mixing an alternating current signal of a first frequency with an alternating current signal of a second frequency to form a composite frequency signal containing at least two frequency components, and generating an excitation signal based on the composite frequency signal; and according to the corresponding excitation scheme, superimposing the excitation signal and a direct current bias voltage to excite the sensor to work in a target mode. The application is based on the principle of nonlinear modal coupling, and the sensor is excited by mixing two alternating current signals of specific frequencies, the interaction between the target working mode and the coupled mode is triggered by using multi-frequency electrostatic force, the Duffing nonlinear effect of the target mode and the energy transfer between modes are enhanced, and the sensitivity, the resolution and the zero bias stability of the sensor are significantly improved.

This invention belongs to the field of sensor signal processing technology. It provides a drift suppression method and system for a six-axis sensor, comprising: acquiring actual operating data of the six-axis sensor; using Allan variance analysis of the actual operating data to perform cumulative analysis on the drift of any axis within the acquisition period to assess the drift risk of the six-axis sensor; if the drift risk of the six-axis sensor is high, extracting the instantaneous zero bias of the accelerometer and the gyroscope, and analyzing whether the zero bias drift trends of the accelerometer and the gyroscope are consistent within the acquisition period; if consistent, extracting temperature data within the acquisition period and performing timestamp matching to determine whether the accelerometer drift and gyroscope drift are caused by temperature. This invention improves the measurement accuracy and stability of the sensor under temperature variation environments, extends the effective service life of the sensor, reduces the need for replacement due to excessive drift, and lowers equipment maintenance costs.

The invention discloses a nanowire photoelectric detector based on a buried interface modification strategy, and relates to the technical field of semiconductor nanomaterials and photoelectric detectors. According to the nanowire photoelectric detector based on the buried interface modification strategy, interface energy level matching of SnO2 and MAPbI3 nanowires is optimized through BMIMHSO4 buried modification, an effective built-in electric field is formed under zero bias voltage, autonomous separation and transmission of photon-generated carriers can be achieved without an external power supply, self-driving is achieved under zero bias voltage, the switching ratio is increased by 5 times compared with an unmodified photoelectric detector, and the photoelectric detector is suitable for large-scale popularization and application. The linear dynamic range is 190 dB, the detection degree is improved by 3 orders of magnitude, the-3dB bandwidth is 9814 Hz, the response speed is high, weak light and high-speed optical signals can be accurately detected, the attenuation rate is reduced, the commercialized service life requirement can be met, meanwhile, a flexible substrate is compatible to adapt to a wearable scene, a low-cost liquid phase process is adopted, materials are cheap, high-price equipment and air environment are not needed for preparation, and the application range is wide. The method is green and easy to scale, and provides technical reference for other perovskite photoelectric detectors.

The invention discloses a ferroelectric tunnel junction based on a two-dimensional TiSe2 / Sc2CO2 Van der Waals heterostructure and a design method thereof, and belongs to the technical field of nanoelectronics. The ferroelectric tunnel junction comprises a left electrode, a central scattering region and a right electrode which are connected in sequence; the left electrode and the right electrode are respectively formed by periodically repeating a TiSe2 / Sc2CO2 Van der Waals heterostructure leftwards and rightwards; the central scattering area is composed of N Sc2CO2 single-layer orthogonal unit cells, the length of the central scattering area is N times of the length of the Sc2CO2 single-layer orthogonal unit cells, and N is a positive integer; the TiSe2 / Sc2CO2 Van der Waals heterostructure is formed by stacking a two-dimensional metal TiSe2 and a two-dimensional ferroelectric body Sc2CO2, and each ferroelectric tunnel junction only comprises the TiSe2 / Sc2CO2 Van der Waals heterostructure in one polarization direction. The device has the ohm-Schottky contact reversible switching characteristic, stable switching of high and low conductivity states under the zero bias voltage condition is achieved, and an important theoretical basis and a feasible implementation path are provided for design of next-generation high-performance ferroelectric logic devices and memories.

This invention discloses a method for preparing a substrate-free bismuth sulfide-based heterojunction thin film and its application in a flexible self-driven photodetector. The heterojunction is composed of hierarchically structured Bi₂S₃ nanofibers and ZnO nanorods, with ZnO nanorods densely coating the surface of ultralong one-dimensional Bi₂S₃ nanofibers, forming a unique brush-like microstructure. The bismuth sulfide-based thin film is self-assembled from interwoven Bi₂S₃ / ZnO heterojunction nanofibers, requiring no substrate support. The unique brush structure formed by this invention not only exhibits a light-trapping effect, effectively improving light absorption utilization, but its heterojunction interface also significantly suppresses the recombination of photogenerated carriers. The detector constructed based on this substrate-free thin film exhibits excellent self-driven detection performance for ultraviolet to infrared light under zero bias, and maintains stable detection capability under bending conditions. This substrate-free flexible broadband detector has significant application prospects in the field of wearable electronics.

The invention discloses a plasmon enhanced self-driven photoelectric detector and a preparation method thereof. The photoelectric detector comprises a quartz substrate, a bottom-layer metal electrode, bottom-layer graphene, a WS layer, an h-BN insulating layer, a plasmon layer, top-layer graphene and a top-layer metal electrode from bottom to top. During preparation, the bottom layer metal electrode is firstly prepared on the quartz substrate by utilizing photoetching and electron beam evaporation technologies, then graphene and WS are sequentially transferred through mechanical stripping and dry transfer technologies, h-BN is transferred through a wet transfer technology, and then the plasmon layer is prepared through photoetching and magnetron sputtering technologies. Then transferring the top layer graphene through a mechanical stripping and dry transfer technology; and finally preparing a top layer metal electrode by utilizing a photoetching and electron beam evaporation technology. The device utilizes plasmon resonance and a vertical structure to enhance light absorption and carrier separation efficiency, and realizes broadband rapid self-driven photoelectric detection under zero bias voltage.

This invention relates to an error correction method for a triaxial sensing chip, comprising: Step 1: Selecting multiple three-dimensional coordinate points as measurement points, placing a device equipped with the triaxial sensing chip at the measurement points, and obtaining the measured values ​​of the measurement points; Step 2: Obtaining the theoretical values ​​of the measurement points; Step 3: Defining the error vector v = [α, β, γ, o] x o y o z ], where α, β, and γ are the angular deviations of the XYZ axes, respectively; o x o y o z The offset or zero bias error of the XYZ three-axis output values ​​is caused by the position error of the three-axis sensor chip; Step 4: Minimize the residual sum of squares function using the nonlinear least squares method to solve for the error vector v = [α, β, γ, o x o y o z The residual sum of squares function: where N is the number of measurement points, x meas，i x true，i Let represent the measured and theoretical values ​​of the i-th three-dimensional sensor chip, respectively; R is a function of angular deviations α, β, and γ; offset = [o x o y o z ] T It is the offset of the output value of the three-axis sensor chip; Step 5: Based on the error vector v = [α, β, γ, o x o y o z The errors of the triaxial sensor chip are corrected using the above method. The triaxial sensor chip corrected using this method can obtain more accurate measurement values.

The invention discloses a robot course correction method and system for a high-voltage power transmission pipe, and relates to the technical field of pipeline robot positioning. The method comprises the following steps: determining a difference value between an actual observation distance and a predicted observation distance of a robot at a moment k as an innovation vector at the moment k; determining an encoder scale factor at the moment k according to the innovation vector and the Kalman gain matrix at the moment k and the encoder scale factor at the moment k-1 of the laser sensor, and correcting the linear velocity of the robot at the moment k according to the encoder scale factor at the moment k; according to the innovation vector and the Kalman gain matrix at the moment k and the zero offset of the accelerometer at the k-1 moment in the inertial measurement unit, determining the zero offset at the moment k, and correcting the acceleration of the robot at the current moment according to the difference value between the acceleration at the moment k and the zero offset; and determining the corrected linear velocity and acceleration at the moment k as the course of the robot at the moment k. The method improves the course correction precision of the robot.

The present disclosure provides a low-cost IMU zero bias suppression method and system based on rotation modulation, which combines zero velocity update (ZUPT) with IMU self-rotation, and the IMU rotates in both zero velocity interval and non-zero velocity interval. In order to solve the problem that the introduction of active rotation of the IMU in the zero velocity interval makes the z-axis gyroscope zero bias observability low during the zero velocity correction, resulting in high-order divergence of the heading angle cumulative drift and position error, the present application constructs a corresponding speed observation model, successfully modulates the z-axis gyroscope zero bias during ZUPT in the traditional PINS into a periodic signal that is easy to estimate by the Kalman filter, and fundamentally solves the problem of system heading drift. At the same time, by establishing a special rotating stationary phase detector to replace the failed traditional ZUPT, the reliable triggering of the filter update is ensured. The present application improves the long-time positioning accuracy and reliability of the system.