473 results about "Temperature error" patented technology

The invention discloses a compensation method for error calibration of an MEMS gyroscope in an MIMU. The method uses a novel error model of the MEMS gyroscope. The method can complete calibration for non-orthogonal errors and temperature errors of the MEMS gyroscope in cases of existing devices: a rotary table with a thermostat and a single shaft being capable of rotating in 360 DEG, and a rotary table without a thermostat and with dual shafts being capable of rotating in 360 DEG; and does not introduce secondary mounting errors, thereby ensuring a calibration precision, overcoming restrictions of calibration devices, and well compensating non-orthogonal errors and temperature drift errors. According to the invention, in a full temperature range, a maximum output error of the MEMS gyroscope is only 0.2 DEG/s, and triaxial errors are also consistent.

The invention relates to an on-line detection system and detection method of machining accuracy of parts for a numerically controlled lathe. The detection system comprises a chuck, a workpiece and a lathe probe, wherein the workpiece is arranged on the chuck, and the lathe probe is arranged at the side of the workpiece; and a signal output terminal of the lathe probe is connected with a controller of the detection system. The detection method comprises the following steps that 1) the lathe probe is arranged at the side of the workpiece; 2) the lathe probe is calibrated; 3) the measuring path and code generation of geometrical parts and curved-surface parts are planned; and 4) the heat distortion temperature error compensation and machining error analysis of parts are carried out by the controller of the detection system. The parts do not need to leave the lathe after being machined, a touch probe is used for replacing a turning tool, and the detection path of the probe is automatically planned and the detection code is generated according to the geometric outline and detection items of the machined workpiece; and through a communication interface of the numerically controlled lathe, the detection code is driven, so that the automatic measurement of the size and precision of size and form of the machined part is realized, and the detection accuracy and efficiency of the workpiece are improved.

The invention relates to a temperature conversion method and a low-power high-precision integrated temperature sensor. The low-power high-precision integrated temperature sensor is composed of a band gap reference circuit with a sensing core, a positive and negative synchronous switch capacitor integral circuit, a current source and a sampling capacitor dynamic element matching module, a clock generating circuit, a divider and buffer circuit and a fully differential analog-to-digital converter. The sensing core circuit in the traditional technology and the band gap reference circuit are combined and integrated, so that the circuit structure is simplified; the current source dynamic element matching module is arranged and thus a base-emitter junction voltage difference in proportion to the absolute temperature is generated, wherein the polarity of the voltage difference changes alternately; with the novel positive and negative synchronous switch capacitor integral circuit, the improved temperature conversion function is completed and the dynamic range utilization rate of the analog-to-digital converter is improved; dynamic element matching is carried out on the sampling capacitor, thereby improving the integral accuracy; and the analog-to-digital converter is used for carrying out quantization processing on an effective temperature signal to provide a digital output. Therefore, the temperature error and circuit power consumption of the sensor can be effectively reduced; and the method and the sensor are suitable for the low-power high-precision temperature sensing application.

The invention provides a method for carrying out ultrasonic inspection on residual stress of an aluminium alloy pre-stretching board by water immersion, belonging to the field of non-destructive inspection. The method comprises the following steps of preparing a reference block; carrying out measurement and calibration; measuring the residual stress. In the method, the water immersion method is adopted, and the temperatures in stress calibration and stress measurement processes can be ensured to be consistent by controlling the water temperature not to be changed, thus eliminating the effects of temperature difference on the ultrasonic wave speed and eliminating temperature errors; besides, an automatic scanning frame is adopted instead of manual scanning, so that the distance between a probe and the surface of a material to be measured in the measurement process can be ensured not to be changed, thus eliminating the effects of coupling condition difference on sound propagation time and eliminating the coupling errors. The method is beneficial to non-destructive evaluation of the near surface residual stress of the aluminium alloy pre-stretching board.

The invention discloses a roadway surrounding rock stress monitoring device based on fiber bragg grating sensing. Grooves are symmetrically carved in a metal rod along the axial center, an FBG set is fixedly installed inside each groove, FBGs serve as sensitive elements, when roadway surrounding rock is deformed, the stress of the surrounding rock will be changed, therefore, force is generated through the metal rod, surface micro-deformation is generated, the grating distances of the FBGs attached to the metal rod are changed along with the metal rod, the center reflection wavelength of the FBGs can be caused to generate drifting, wavelength signals are demodulated into electrical signals through an FBG interrogator, and the stress situations of different sites can be obtained. The roadway surrounding rock stress monitoring device has the advantages that installation is easily achieved, and the roadway surrounding rock stress monitoring device is suitable for wide popularization; power is not required to be supplied to the working face end, and site safety is guaranteed; all-optical measurement and fiber transmission are adopted, and influences of electromagnetic interference are effectively avoided; the temperature error is compensated, and the accuracy is improved; the surrounding rock stress monitoring results can be timely and accurately provided, and guidance on site production and scientific research is facilitated.

The invention belongs to the technical field of all-fiber current transformers, and particularly relates to a high-precision high-reliability and all-fiber current transformer. A redundancy design method adopting active optical devices is applied so that output optical power of light source units is enabled to be more stable and stability of light source average wavelength is enhanced. A depolarization head is additionally arranged in an optical path system so that stability and measurement precision of the optical path system can be enhanced. Two beams of light are converted into electric signals to be transmitted to a signal processing unit by utilizing correlation of output light of the two output ends of a second single-mode coupler through a digital signal processing unit, and suppression of light source intensity noise is realized by utilizing a digital circuit subtraction method so that signal-to-noise ratio is enhanced and measurement precision of the system is enhanced. A low birefringence optical fiber Verdet constant and a transformation ratio error generated by change of wave plate phase delay along with temperature are enabled to be mutually compensated via an all-fiber current transformer transformation ratio temperature error automatic compensation technology so that full-temperature measurement precision of the system is enhanced.

An optical fibre gyroscope distributed layered temperature error compensation method comprises the following steps: (1) five optical components of a fiber-optic ring, a light source, a Y wave guide, a detector and a coupler are taken as temperature monitoring objects for determining the number of the temperature monitoring points of each optical component and the distributing form; (2) self-adapting recurrence and least squares treatment are carried out on monitoring value of each temperature monitoring point for obtaining temperature output value of the optical fibre gyroscope; (3) a neural network model is built for obtaining temperature drift compensation value by utilizing the temperature output value and the real time outputting data of the optical fibre gyroscope; (4) the real time outputting data of the optical fibre gyroscope minus the temperature drift compensation value means temperature compensation of the optical fibre gyroscope. The method can overcome the disadvantages of the prior art and reflect the temperature field inside the optical fibre gyroscope systematically and in an all-round way, and has significance in the performance research and improvement under the condition of the temperature environment of the optical fibre gyroscope.

The invention discloses a method for simultaneously compensating a scale factor and a zero offset of an optical fiber gyroscope by a one-time temperature experiment. The method comprises the following steps: (1) adjusting the temperature of an incubator, rotating the gyroscope clockwise and anticlockwise when the temperature reaches respective set temperature values, and acquiring temperature data acquired by a temperature sensor in the gyroscope in real time and data which correspond to the temperature and are output by the gyroscope in the whole process of switching on and switching off the incubator; (2) processing the temperature data and the data output by the gyroscope according to a simultaneous scale factor and zero offset compensation algorithm, and obtaining a temperature compensation coefficient matrix; (3) compensating the output of the gyroscope according to the temperature compensation coefficient matrix. According to the compensation method provided by the invention, the one-time temperature experiment is designed to simultaneously compensate the scale factor and the zero offset of the optical fiber gyroscope; a relation between a digital value output by the gyroscope and an input angle speed is directly expressed, so that the compensation coefficient matrix is obtained; therefore, the inaccuracy, which is caused by a zero offset error and the like, of compensation of the scale factor is avoided; furthermore, the temperature error of the gyroscope can be effectively compensated, and the method can save the experiment cost and is higher in practical significance.

The embodiment of the invention provides a depth image calibration method and system for a TOF camera system, and the method comprises the steps: obtaining a corresponding depth image according to anoriginal phase image collected by the time-of-flight TOF camera system; And respectively carrying out geometric correction, time domain noise reduction and spatial domain noise reduction processing, FPPN correction, Wiggling correction and temperature error compensation on the depth image to obtain a calibrated depth image. multi-aspect calibration is carried out on a depth image; geometric correction, time domain noise reduction and spatial domain noise reduction processing, FPPN correction, Wigning correction and temperature error compensation are carried out, errors introduced from multipleaspects are eliminated, a calibrated depth image is obtained, so that the measurement error is greatly reduced, the reliability of the finally obtained depth image is greatly enhanced, and the methodcan be further applied to various depth applications.

The invention discloses a PID temperature control method that employs the follow-up control-based temperature-increasing and/or temperature-decreasing process. The method specifically comprises the steps of presetting a temperature/time curve, obtaining the temperature measurement value of a controlled object at the current time, calculating a temperature target value at the current time according to the temperature/time curve, conducting the PID operation according to the temperature measurement value and the temperature target value at the current time, and adjusting the output power according to the result of the PID operation so as to complete the power adjustment at a time. The invention also discloses a PID temperature control module. The PID temperature control module comprises a temperature measurement value acquisition unit, a follow-up control temperature target value calculation unit, a PID operation unit and an output unit. According to the technical scheme of the PID temperature control method and the PID temperature control module, the temperature-increasing and temperature-decreasing process is controlled in the follow-up control manner. Therefore, the temperature can be increased or decreased at a constant speed according to a well designed temperature increasing/decreasing curve. The heating power is controlled to fluctuate within a relatively small range. The temperature error caused by the large inertia can be reduced. Meanwhile, the accuracy of temperature control is improved.

The invention relates to a self-tuning PID energy-saving temperature control method. The method comprises the steps that a target temperature value, a control period, a sampling period and a thresholdtemperature difference are set first; load heating power is increased; the current regional temperature sampling value of a controlled object is acquired, and the sampling period is combined to calculate the temperature rise rate; a PSO-DE algorithm combining particle swarm optimization (PSO) and differential evolution (DE) is used to adjust and calculate PID control parameters; the duty cycle ofthe output pulse of a control period is adjusted according to the operation result; heating power output is adjusted, so that the sampled temperature sampling value is approximately equal to the actual temperature value of the controlled object; a temperature error caused by the heating inertia is reduced; heating power is accurately controlled; and the energy saving effect is obvious. A self-tuning PID energy-saving temperature control module comprises the self-tuning PID energy-saving temperature control method, can accurately control the heating power, and has an obvious energy-saving effect.

The present invention is directed toward a laser wavelength locking scheme suitable for incorporation into WDM systems having channel spacings of 25 GHz or less. In a preferred embodiment, light output from the laser is supplied to a filtering element, such as an in-fiber Bragg grating or an etalon, and photodetectors are used to sense light transmitted through and either reflected by the filtering element or input to the filtering element. A measured ratio corresponding to a quotient of the photocurrents generated by the photodetectors is calculated and compared to a desired ratio corresponding to a measured temperature of the filtering element when the filtering element transmits the desired wavelength to be locked. Based on the comparison of the desired and measured ratios, a temperature error value is calculated which is used to adjust the laser temperature, as well as the laser wavelength. Accordingly, the temperature of the filtering element, for example, influences the laser temperature, so that wavelength variations stemming from temperature induced changes in the filtering element and other components in the laser package can be compensated, and the output wavelength can remain substantially fixed.

The invention discloses a test structure for measuring the thermal conductivity of a film, which comprises a substrate and an insulating layer arranged on the substrate, wherein a test unit is arranged on the insulating layer, and the test unit comprises a reference unit and a test unit. The structure has simple preparation process and convenient test and is particularly suitable for measuring the thermal conductivity of a silicon nitride (Si3N4) film in a natural air environment. An S-shaped heater made of platinum (Pt) is adopted and can achieve more uniform heating temperature and reduce temperature error, and moreover, the S-shaped heater has higher test precision.

The invention discloses a real-time monitoring and analyzing system for a substation. The real-time monitoring and analyzing system comprises a data acquisition module, a data transmission module and a data processing module. The data acquisition module is mounted on an inspection vehicle and enabled to freely move for acquiring data of various devices in the substation. The data acquisition module transmits data to the data processing module through the data transmission module, and the data processing module performs real-time monitoring and intelligent analyzing to realize remote intelligent monitoring of power equipment. The real-time monitoring and analyzing system for the substation has the advantages that monitoring ranges and objects can be selected independently and flexibly, the defect of immovability of monitoring platforms mounted in fixed points is overcome effectively, monitoring ranges are widened, the problems of inaccuracy in temperature measurement of voltage heating equipment due to temperature errors resulted from remote monitoring are reduced, operation efficiency is improved, and manpower and material resources are saved. The invention further provides a real-time monitoring and analyzing method for the substation.

The present invention relates to an intelligent hot plate temperature controller and a control method thereof. The temperature controller is provided with a main control circuit; the input end of the main control circuit is connected with a hot plate temperature sensor through a temperature detection circuit, and the output end is connected with a hot plate heating device through a temperature control circuit; the main control circuit is also connected with a human-machine interface circuit; and a single chip is used as a control core of the main control circuit and is provided with an internal hot plate temperature control program. The control method comprises the following steps: initializing the configuration and parameters of the electrified system; reading the contents of the memory; modifying the target temperature and various parameters according to needs; acquiring the current actual temperature of the hot plate with the main control circuit through the temperature detection circuit; comparing the current actual temperature with the target temperature to obtain the temperature error; and performing the PID adjustment of the temperature error, so that the actual temperature is maintained at the target temperature. The present invention has the advantages of accurate and constant control, rapid response and consistent repeatability of the temperature when the machine is repeatedly started, and can accurately track the technical process, improve the yield rate, facilitate the debugging and save the time.

The invention belongs to the field of inertial device error compensation, and specifically relates to a temperature error compensation method during MEMS inertial measurement unit cold start. The temperature error compensation method comprises: (1) selecting a temperature error compensation model, collecting temperature compensation data, pre-treating the temperature compensation data, optimizing temperature compensation error model parameters, and carrying out temperature compensation. According to the present invention, the improved temperature error compensation model and the corresponding, simple and easy performing work process are provided based on the gyro and the accelerometer in the MEMS inertial devices; and when the MEMS inertial measurement unit being subjected to temperature compensation is subjected to cold start, the influence of the temperature increase and the external temperature change is low, such that the preparing time of the MEMS inertial measurement unit is substantially shortened, and the speedability of the MEMS inertial measurement unit as the navigation system is increased.

The invention discloses a method for improving bridge deflection testing precision based on an inclinometer. The method is mainly used for improving the bridge deflection testing precision by three aspects of temperature error compensation, improvement of signal-to-noise ratio through band-pass filtering, and improvement of a deflection calculation method based on a dip angle value. The method comprises the following steps of a, carrying out temperature calibration on a to-be-used inclinometer in a one-to-one manner, b, acquiring inclination angles corresponding to a plurality of designated positions on the bridge, c, carrying out temperature drift error correction on the obtained inclination angle values by adopting respective pre-calibrated inclinometer temperature error compensation formulas, d, adopting a band-pass filtering algorithm for preprocessing the dip angle values, and eliminating noise influence, and e, adopting an improved conformal spline function fitting method to calculate the bridge deflection. According to the method, on one hand, the inclinometer measuring point arrangement is free of any restriction, and on the other hand, the calculation precision of an original test method is greatly improved, and the dynamic deflection of the bridge can be monitored in real time.

The invention relates to the field of sponge products, and specially, relates to a technology for producing sponge from a plant oil polyether. The technology comprises a raw material supply process section, a mixing process section and a foaming process section. The technology is characterized in that through extraction and synthesis, a plant oil polyether polyol is prepared from plant oil raw materials; raw materials adopted by the raw material supply process section comprise a polyol component and an isocyanate component; the polyol component comprises the plant oil polyether polyol, a chain extender, a foaming agent, a catalyst and a foam stabilizer; the isocyanate component comprises isocyanate; the raw materials are respectively input into a work storage tank; and a work storage tank temperature is controlled in a range of 20 to 25 DEG C by a temperature control system, wherein the temperature error is less than 1DEG C. The technology has the advantages that a plant oil polyether replaces a traditional petroleum polyether to be utilized for production of sponge (comprising common sponge and slow-rebound sponge), and thus waste sponge degradation is realized; environmental pollution is reduced; and environmental protection and sustainable development can be promoted.