100results about How to "Avoid imprecision" patented technology

The invention discloses a nonlinear robust controller design method based on back-stepping and sliding mode control technologies and aimed at a nonlinear model of a quad-rotor unmanned plane. A sliding mode controller of a speed-constant reaching law is designed to an attitude angle system of the quad-rotor unmanned plane, and rapid tracking for the attitude angle is ensured. To realize track tracking for the spatial position of the quad-rotor unmanned plane, a sliding mode surface and a virtual control quantity are constructed according to a stepping back control idea to realize nonlinear control law design and system stability design from the kernel to the external layer of a system. After an equation of the related virtual control quantity is obtained, an expected track value of the attitude angle is obtained by solving the equation via arithmetic inverse operation, and a design method of the speed-constant reaching law is used to determine a final input control law of the quad-rotor unmanned plane system. According to the method of the invention, the characteristic that sliding mode control is uncertain for the model and insensitive to external interference is utilized, robust trace tracking for the nonlinear quad-rotor unmanned plane can be controlled under interference.

The invention provides a structured light visual sensor parameter calibration method for acquiring height information of a welded joint, relates to the measurement non-specially applied to specific variable, and is a structured light visual system parameter calibration method based on a wedge-shaped target, which processes a two-dimensional image to obtain offset of structured light by calibrating obtained parameters so as to compute and obtain the height information of the welded joint and then to compute three-dimensional coordinate of an intersection point of a laser belt and the welded joint on the target, wherein the structured light visual sensor parameter calibration method specifically comprises the following steps of firstly recognizing horizontal deviation, secondly recognizing vertical deviation, thirdly calibrating structured light visual system parameters by utilizing a camera, and fourthly acquiring the height information of the welded joint. According to the structured light visual sensor parameter calibration method disclosed by the invention, the calibration process doest not involve a large-scale matrix transformation, the computation amount is smaller, a blockage problem of the target doest not exist, and the problem that the misconvergence of globally optimal solution generates in a solving process of a constrained nonlinear equation also does not exist.

The invention relates to a calibration method for a line-structured light sensor based on mechanical movement and a device. The device comprises a camera, a laser, a calibration plane and a movement mechanism. The method comprises the steps that 1) a z-axis of a world coordinate system taking the calibration plane as the ground acts as the vertical direction, an intrinsic parameter A of the camera and an extrinsic parameter of a first checkerboard are acquired by using Zhengyou Zhang checkerboard calibration, and included angle alpha between a z-axis of a camera coordinate system and the vertical direction is acquired by using the extrinsic parameter; 2) the distance between corresponding points on adjacent laser stripes and corresponding image point coordinates are calculated; 3) a normal vector of a structured light plane is solved; and 4) an included angle theta between the structured light plane and the vertical direction is calculated according to the normal vector acquired in the step 3) and the included angle alpha between the z-axis of the camera coordinate system and the vertical direction, and the coordinates of a point on the structured light plane in the camera coordinate system are further acquired so as to complete calibration for a structured light plane equation.

The invention discloses a plant rhizosphere box and the application thereof in the micro-domain research of wet land plant rhizosphere. The plant rhizosphere box comprises a box body, the inside space of the box body is partitioned into a root zone, a near root zone, a far root zone and a non-root zone and other different rhizosphere micro-domain partition zones by a number of rhizosphere partition plugging plates, water distribution units are arranged on the upper part of the box body, and water level regulating units are also arranged on the box body; and a water discharging device is arranged on the bottom of the box body. Through the adjustment of the intervals between the different rhizosphere micro-domain partition zones, the accurate observation and the research of the differentiation changes of different distances from the root system, and / or root zone soil, and / or interval water nutrients, pollutant, and / or microorganism are achieved. Based on the plant rhizosphere box, water flooded habitat of plants grown in wet land can truly be simulated, so that water flow conditions in the substrate can be maintained, and different water pressure retention time and water levels are arranged according to the needs, and the plant rhizosphere box has wide application prospect in plants, especially in the micro-domain research of wet land plant rhizosphere.

The present invention provides a method and a system for detecting and distinguishing a passive synthetic aperture target signal, wherein the method comprises the following steps: step 101) constructing a motion doppler receiving model for a target signal under motion of a towed array sonar; step 102) respectively performing cross correlation averaging on target signals which are received by a hydrophone at an overlapping part on spatial position according to a passive synthetic aperture sonar algorithm when the array performs two successive motions in a fixed time interval, and then performing frequency domain wave beam forming treatment on the target signals which are received by array elements at different time periods; step 103) performing energy integration on the output sub-frequency-bands after forming of the frequency domain wave beam for obtaining wave beam output of each time interval; step 104) performing phase estimation on time delay and spatial position movement according to the doppler receiving model, and acquiring a phase correction factor according to the phase estimation; and step 105) compensating the wave beam output through each phase correction factor of time interval, and performing cross combined accumulation on the compensated wave beam output and realizing detection on the target through a time orientation process map.

The invention relates to a gear cutting machine for the grinding of external profiles and / or internal profiles of workpieces having at least one machining head which can be rotated about an axis and which has a grinding tool, and having a dressing unit. In accordance with the invention, the dressing unit is supported in the region of the pivot axis of the machining head such that it is pivotable about the common pivot axis together with the machining head and such that it can be moved along the pivot axis toward the grinding tool to be dressed.

The present invention provides a method for triggering a coverage level change report in a user equipment of a communication system based on machine type communication, the cell where the user equipment is located has multiple coverage areas, and the multiple coverage areas The area includes at least one coverage enhancement area and a normal coverage area, and the method includes: a. Determining whether the coverage area where the user equipment is located is based on the number of retransmissions and the predetermined number of times required for the user equipment to decode the channel changes, wherein the predetermined number of times is the number of times the user equipment continuously decodes the channel with the required number of retransmissions; and b. when the coverage area where the user equipment is located changes, trigger And send a coverage area change report to the base station.

The invention relates to a device for improving the test accuracy of spectrum absorbance on the basis of terahertz optical combs. The device is characterized in that one of two ultrafast laser pulse beams with set repeat frequency difference is transmitted through a terahertz wave generating system to generate terahertz waves, terahertz wave signals and the other ultrafast laser pulse beam are respectively focused and are jointly transmitted into a photoconductive detection antenna, the terahertz waves can be quickly scanned by the aid of tiny repeat frequency difference between pump beams and probe beams, a digital converter is controlled by the aid of a cross-correlation instrument and a rubidium atom frequency standard, the signal acquisition time is prolonged to obtain time-domain spectra of continuous terahertz pulse chains, terahertz comb-shaped spectra are obtained by means of Fourier transformation, accurate change of the optical combs is compared before and after sample placement, and accordingly terahertz absorption spectrum lines of samples can be obtained. The device has the advantages that the shortcoming of excessive scanning time consumption of mechanical delay devices can be overcome, the problem of inaccuracy of existing terahertz super-continuous spectra due to laser pulse time jitter can be solved, and the test accuracy of the terahertz spectrum absorbance can be improved.

The invention relates to a laser anti-collision early warning system used for a bulk cargo stockyard. A stacker-reclaimer with a cantilever is distributed in the bulk cargo stockyard. The system comprises two laser scanners which are installed on the two sides of the cantilever of the stacker-reclaimer respectively, and an anti-collision device which is in network connection with the laser scanners; the laser scanners obtain barrier information within the scanning range and output scanning point location data containing the barrier information, and the anti-collision device comprises a single-chip microcomputer. According to the laser anti-collision early warning system, the barrier information in the set range of the two sides of the cantilever of the stacker-reclaimer is collected in real time through the laser scanners, the single-chip microcomputer in the anti-collision device is used for processing the scanning point location data containing the barrier information, finally corresponding warning signals are output to a PLC system of the stacker-reclaimer so as to enable the stacker-reclaimer to slow down or stop timely, and therefore collision accidents can be effectively avoided.

A method of manufacturing an article, comprising taking an article formed in an initial state via an additive manufacturing process and performing a second manufacturing process to transform the article into a second state, which comprises mounting the article in a holding device, processing at least one first feature on the article, which comprises processing at least one set of mounting features on the article, re-mounting the article via the at least one set of mounting features, and then processing at least one second feature on the article.

An embodiment of the invention discloses a pH value controller of limestone slurry of a desulfurization system. The controller comprises a first measuring module connected with a first microprocessor and a second microprocessor and used for measuring mass flow of SO2 entering an absorption tower and a second measuring module connected with the second microprocessor and used for measuring the pH value of the limestone slurry in the absorption tower. The first microprocessor is connected with a third microprocessor and used for determining supply slurry flow theory value, the second microprocessor is connected with a subtracter and used for determining pH primary value, and the subtracter is connected with the third microprocessor and used for conducting subtraction on the pH primary value and the pH value of the limestone slurry to obtain supply slurry flow modification value. The third microprocessor is used for controlling actual supply slurry flow of the limestone slurry according to results of supply slurry flow theory value modified through the supply slurry flow modification value. The pH value controller achieves complete automation of pH value control.

An industrial robot vibration suppression method includes recording the given position issued from a control system and actual position information fed by an encoder during moving of a robot, calculating position compensation and speed compensation according to the deviation value between the given position and the feedback position, providing the position compensation to the given position, providing the speed compensation through a speed feed-forward interface, thereby realizing vibration suppression to the robot. According to the method, the position encoder of the industrial robot is useddirectly, external sensors are omitted, and thus, optimization cost is saved, data error caused by arrangement of peripheral devices is avoided. The method cannot only solve the problem about vibration in action of the robot but eliminate vibration in positioning. The position compensation and the speed compensation can be reused if the moving track of the robot does not change since the vibrationsuppression compensation is acquired by study, and accordingly, study on vibration suppression can be omitted.

The present invention discloses an island parallel operation control method based on a high-capacity energy storage system. the improved droop control at the operation of the energy storage system considering the storage battery charge state is employed. the control method divides the system into three operation states according to the different charge states, a hysteresis controller is employed to obtain the changing droop factor to regulate the power state of the storage battery in real time to allow the storage battery to perform charging and discharging in advance according to the state of the storage battery so as to ensure that the storage battery is located at the safe operation range and allow the charge state of the storage battery to have the effect of equal distribution of the power. The defects are overcome that the safety operation range of the charge state of a traditional battery is small, the storage battery is easy to generate the overcharge and over-discharging phenomenon and the service life of the storage battery is low.

The invention discloses a DSTATCOM negative-sequence current cross coupling compensation control method. Conventional dq conversion software phase-locking closed-loop control complexity is avoided by the adoption of a digital phase-locking method with a sine and cosine trigonometric function as a two-dimensional orthogonal basis. In addition, the complexity of current negative-sequence current compensation control coordinate conversion control is overcome, a cross coupling negative-sequence current control strategy is provided, cross coupling is carried out on the negative-sequence current closed-loop controller output value in the counterclockwise rotation dq coordinate system to the positive-sequence reactive current or positive-sequence harmonic current current-voltage conversion result, and unified space vector control is carried out.

The invention discloses an electric power daily load prediction method. The method comprises the following steps: 1, ; and establishing a load category set, establishing a key influence factor set, calculating a classification rule between the load category and the key influence factor characteristic value to establish a classification model, analyzing the category to which the key influence factor data of the day to be predicted belongs, training a load prediction model, and calculating a power load prediction result by using the load prediction model. According to the scheme, the problem that a load prediction model is inaccurate due to divergence of load data can be effectively avoided, the accuracy of a prediction result is improved. Meanwhile, the data dimension in the prediction process can be reduced, the calculation efficiency is improved, the power generation requirement and the power selling requirement can be effectively met, economic benefits are guaranteed, and developmentof power market economy is promoted.

The invention discloses a mechanical property and fracture failure simulation modeling method for a welded joint. The method comprises the following steps of: before finite element modeling; firstly,determining the temperature change conditions of different areas in the welding process; slicing a weld template, performing testing to obtain material constitutive parameters of each tensile sample;during finite element modeling, applying material constitutive parameters of each tensile sample to each micro-area, so that different micro-regions have different mechanical property parameters, themechanical property of the micro-region of the welding joint is accurately described, the modeling precision and the modeling accuracy are greatly improved, and the problem that the model is inaccurate due to the fact that the whole welding joint adopts constitutive parameters of the same material is avoided.

The invention provides a radiation source positioning method based on receiving signal power information. The radiation source positioning method comprises the steps that a standby detection terminal set is selected; detection terminals used for positioning calculation are selected; signal power received by all the detection terminals within the designated frequency range and time period are calculated; rough positioning is performed by utilizing the position coordinates of all the detection terminals and the received electromagnetic power; and positioning is performed again by utilizing the rough positioning result so that an accurate positioning result is obtained. Positioning of a radiation source is enabled to be more accurate and reliable by two times of positioning; and a local ground rectangular coordinate system is adopted in transformation of the position coordinates of all the detection terminals so that the problem that large error is possibly generated in transformation of geodetic coordinates to geocentric rectangular coordinates can be avoided.

The invention discloses a RBPF-based filtering combined laser SLAM mapping method and device combining an extended information matrix, and the method is characterized by comprising the following stepsof estimating the current pose of the robot based on the current sensor observation information of the robot; performing map matching processing based on the current sensor observation information ofthe robot and the current pose of the robot to obtain map information; performing proposed distribution calculation based on the pose of the robot in the last moment, the current sensor observation information and the map information to obtain a proposed distribution probability value; performing extended information filtering update on the sampled particles based on the proposed distribution probability value; performing re-sampling processing on the particles in the updated particle set according to the weight value to obtain a re-sampled particle set; and updating the map information basedon the re-sampled particle set. In the embodiment of the invention, the real-time operation efficiency of the robot using laser sensors to map and locate in the indoor non-linear structure environment can be effectively improved.

The invention discloses a geological disaster landslide real-time monitoring and management system based on big data. The system comprises a region division module, a monitoring point arrangement module, a compactness detection module, a compactness analysis module, a water content detection module, a water content analysis module, a displacement monitoring module, a displacement analysis module,an analysis server, a landslide region analysis module, a display terminal and a storage database. According to the invention, a landslide region is divided through a region division module, the compactness of soil in each sub-region is detected, the soil type corresponding to the compactness of the soil in each sub-region is screened while the water content and space coordinates of the soil in each sub-region are detected, the stability influence coefficient of landslide in each sub-region is calculated, whether the landslide of each sub-region is in a safety stage is compared and analyzed, the sub-regions in a dangerous stage are classified according to different depths, and a dangerous comprehensive region is determined and displayed, so that the life and property safety of personnel isguaranteed.

The invention discloses a textile fabric cutting device with an accurate positioning function. The textile fabric cutting device comprises a base. A first slide groove is formed in a side of the outerwall of the top of the base, a first slider is slidably connected with the inner wall of the first slide groove, a support rod which is vertically arranged is welded on the outer wall of the top of the first slider, a transverse beam which is horizontally arranged is welded on the top of the outer wall of a side of the support rod, an electric slide rail is fixed to the outer wall of the bottom of the transverse beam by the aid of screws, a second slider is slidably connected with the inner wall of the electric slide rail, a cylinder is fixed to the outer wall of the bottom of the second slider by the aid of screws, a connecting plate is welded at the bottom of the cylinder, a tailoring device is fixed to the outer wall of the bottom of the connecting plate by the aid of screws, clamp grooves are formed in four corners of the outer wall of the top of the base, and auxiliary magnets are clamped inside the clamp grooves. The textile fabric cutting device has the advantages that the textile fabric cutting device is simple in structure, the problem of inaccuracy due to manual operation cutting can be solved by the aid of the textile fabric cutting device in the integral design, the cutting accuracy can be guaranteed, and excellent cutting effects can be realized.

The embodiment of the invention provides an apportionment mapping method and apparatus of a communication cell and a geographical area, and relates to the field of communication geographic data processing. The matching relationship between the communication cell and the geographical area can be determined more accurately. The method comprises the following steps: performing offset processing on the longitude and latitude of a base station according to the geographical data of the communication cell to obtain the longitude and latitude of the communication cell; constructing a Tyson cell corresponding to the communication cell according to the longitude and latitude of the communication cell; dividing a grid into at least one subarea according to boundary data in the geographical data of the Tyson cell and the geographical data of the grid; calculating the area of the subarea and the longitude and latitude of a centroid of the subarea according to the geographical data of the subarea; matching the subarea with the Tyson cell according to the longitude and latitude of the centroid of the subarea and the geographical data of the Tyson cell; calculating the area of the Tyson cell according to the geographical data of the Tyson cell; and calculating a ratio of occupation of the area of each subarea matching the Tyson cell to the area of the Tyson cell.

Device for locking and quickly unlocking moving components comprises a housing (7) having a contour which fits an actuator (1) or electromagnet. The actuator or electromagnet is held in a non-moving or non-sliding position and bearing sites for all catches of a safety catch (3) are formed in the housing. The housing has connecting parts for connecting the actuator to a connector arranged on the housing. The connector is fixed to an external connecting part. Preferred Features: The safety catch has an actuating catch (2) directly actuated by the actuator. The bearing sites for the actuating catch and for the safety catch are formed by bolts (14, 15) arranged on the housing.

The invention discloses a device for automatically blending pesticides and a control method. The device comprises a water tank, a pesticide mixing tank, a pesticide box and a master controller; a water outlet of the water tank is connected with a water inlet of the pesticide mixing tank through a pump water pipe; a pesticide outlet of the pesticide box is connected with a pesticide inlet of the pesticide mixing tank through a pesticide feeding pipe; a pesticide feeding channel is arranged on the upper end of the pesticide mixing tank; the pesticide outlet of the pesticide mixing tank is connected with a pesticide tank of a spraying device through a pump pesticide pipe; the master controller is used for controlling the volume of pesticides conveyed into the pesticide mixing tank through thepesticide box, the volume of clean water conveyed into the pesticide mixing tank through the water tank, the blending of pesticides in the pesticide mixing tank and the volume of pesticide liquor conveyed to the pesticide tank of the spraying device through the pesticide mixing tank. Pesticide water separation, real-time blending, sufficient mixing and accurate ratio are adopted by the device, sothat the dosage of pesticides and the inflow volume of clean water in the pesticide mixing tank can be effectively controlled and the dilution ratio and the pesticide concentration can be accuratelymeasured.

The invention relates to the field of Internet information processing, and provides a monitoring safety prediction method and system based on a chaotic particle swarm optimization algorithm optimization prediction model, equipment and a medium aiming at the defects of high randomness, large calculation amount, low speed and low efficiency of a parameter adjustment method in an existing data safety monitoring model. A sample data set is divided into a plurality of training subsets and a test set, parameter optimization of a constructed prediction model algorithm is performed by using the plurality of groups of training subsets according to a chaos particle swarm optimization algorithm, and a plurality of groups of optimal parameters are acquired, so that a model with optimized parameters is trained and is utilized to complete prediction of monitoring data. The optimization process is added to the modeling process to achieve parameter optimization, model inaccuracy caused by randomness is avoided, the optimization process is improved in combination with the chaos thought, the parameter optimization effect is improved, the parameter optimization speed is increased to optimize model efficiency, model quality and reliability are guaranteed, and then data safety monitoring accuracy and judgment efficiency are improved.

The invention relates to a method for automatic hydraulic compensation of heating and / or cooling systems (1) having a heat and / or cold producer (2), a plurality of loads (4) connected in strands, and a circulating pump (5), wherein control valves (8) provided with actuating drives (7) are installed in the pipeline strands (6) in order to control the strand differential pressures, wherein in a first method step the differential pressures of the inlet side (10) and outlet side (11) of the control valves (8) are detected and subsequently the strand differential pressures between the feed line (12) and the return line (13) are detected by one differential pressure sensor (9) per pipeline strand (6) and the detected measured data are read into a computing unit (14) and are stored in said computing unit, and in a second method step the strand differential pressures in all pipeline strands (6); are continuously measured, the measured data are transferred to the computing unit (14) and compared with the stored data pattern, wherein actuating commands are generated from the determined comparison data by the computing unit (14). The current strand differential pressures are controlled to the stored target differential pressures by the actuating drives (7) of the control valves (8) by means of said actuating commands.

The present invention relates to a microswitch. In an electric switch, preferably a microswitch, the switch is provided with at least one contact spring transferred into different switching positionsby an actuating element and arranged at an anchor formed as an electrical contact. The contact spring has a closed spring frame; two spring tongues which are easy to bend and extend to opposite directions are fixed on the spring frame. A first spring tongue is formed as a resetting unit for the actuating element. A second spring tongue controls switching functions of a contact region of the springs. The tongues are engaged at surface regions of the anchor in a supporting manner such that the springs exhibit stable position during actuation.

Each base station in a network has an antenna (1) which is connected in the conventional way to a transceiver (2) for handling normal call traffic on one or more radio channels. In addition there is another transmitter (3) which transmits a test signal on each of several test channels, one for each radio channel available for use by the main transceiver (2). The transceiver also has a receiver (4) for detecting the test channels. The system is controlled by a timer (5) which ensures that the transmitter (3) and receiver (4) do not operate at the same time. The receive times may be random, or may be co-ordinated between individual base stations. When the receiver is in operation, it will detect transmissions of the test signals from other base stations. The signal strength is measured (measurement system (6)) and the result is used by a control system (7) to determine a preference value for each channel: the stronger the signal detected, the lower the preference value. The preference value is used to control an amplifier system (8) which controls the signal strength of each channel transmitted by the transmitter (3). It is also used to control the traffic transceiver (2), by selecting which traffic channels are to be used in accordance with the preference values.

The invention discloses a rubber expansion joint space attitude detection device and method. The device comprises a stay wire type sensor module, which comprises three stay wire type sensors, whereinthe installation block ends of the three stay wire type sensors are fixed on a first flange plate at the other side of a rubber expansion joint, and the wire ends of the three pull wire type sensors are fixed at the same fixed point of a second flange plate on one side of the rubber expansion joint; a PSD photoelectric position sensor module, which comprises two PSD photoelectric position sensorsand two solid lasers, wherein the two PSD photoelectric position sensors are fixed to the first flange plate on one side of the rubber expansion joint, the two solid lasers are fixed to the second flange plate on the other side of the rubber expansion joint, and laser emitted by the two solid lasers irradiates the four quadrants of the two PSD photoelectric position sensors respectively; and a signal receiving and processing module, which is used for receiving voltage signals generated by the stay wire type sensors and the PSD photoelectric sensors and obtaining the spatial attitude of the rubber expansion joint through calculation.

The present invention discloses a permanent magnet synchronous motor model modeling method based on data statistics and numerical optimization. According to the method, a testing bench formed by a host machine, a d-axis current estimation model, a q-axis current estimation models and a torque estimation model is built, and the input and output parameters of each estimation model are set respectively; the host machine sets motor automatic operation condition and collects needed data; and for each motor rotation speed point, each scanning point of d-axis voltage and q-axis current has d-axis current, d-axis current estimation second-order model, a q-axis current estimation second-order model and a torque estimation second-order model are established respectively, and the quadratic equation fitting is used to obtain d-axis current, q-axis current and an output torque to be the characteristic parameter of a permanent magnet synchronous motor model to carry out derivation modeling. The experiment testing data is employed, a motor model is established based on statistics and numerical optimization, the inaccurate model problem in formula modeling is solved, thus the accuracy of the motor model is within 5%, and the system level analysis is carried out well.

The invention discloses a method for estimating the content of sulfur oxide at an inlet of a desulfurization system based on as-fired coal quality measurement. The method comprises the following steps: 1, recording historical data of key parameters; 2, constructing a sulfur content steady-state conservation equation; 3, determining the sulfur-containing oxidation weight gain coefficient of the coal; 4, establishing a desulfurization system inlet sulfur oxide dynamic transfer function; 5, performing parameter identification to obtain dynamic parameters; 6, obtaining the prediction of the sulfur oxide content at the inlet of the desulfurization system; The sulfur content of the coal is obtained through a coal quality online detection device, and a desulfurization system inlet sulfur oxide content calculation model is established through the sulfur content before entering the furnace and the desulfurization system inlet sulfur content conservation theorem, so that the desulfurization system inlet sulfur oxide content change condition is obtained; Therefore, subsequent accurate limestone slurry demand quantity calculation and slurry pump control are guided.