2203results about How to "Improve calibration efficiency" patented technology

The invention relates to a vector-relation-based method for calibrating single-line laser radar and a CCD camera. Point set information of the laser radar for scanning a V-shaped target is extracted in a laser coordinate system, and direction vectors and intersection coordinates of straight lines in two different planes of the target are obtained by means of straight line fitting; the CCD camera is used for capturing images in a camera coordinate system, target plane equations and an equation of a plane passing through an original point and laser radar scanning lines are obtained by processing image information, a straight-line equation of laser radar scanning is built, and furthermore, the direction vectors and the intersection coordinates of the straight lines are obtained; finally, calibration is finished according to the relations between direction vectors and the intersection coordinates of the straight lines corresponding to the different coordinate systems. According to the method, no object in a calibration scene needs to be moved, collection of all calibration data can be completed at a time, and calibration efficiency is improved greatly. According to the method, the direction vectors of the straight lines of the laser scanning target planes under the coordinate systems of sensors to be calibrated are obtained directly, calibration precision is guaranteed, and meanwhile the calibration algorithm is simplified.

The invention discloses a robot eye-on-hand system structured light plane parameter calibration device and a method. According to the device, a camera and a laser device are installed at the tail end of a robot to form a robot eye-on-hand system, and on the premise of obtaining camera intrinsic parameters, plane parameters of structured light projected by the laser device are calibrated, and thereby structured light three-dimensional vision measurement can be achieved. The robot eye-on-hand system structured light plane parameter calibration method includes that a plane checkerboard target is placed in a calibration area, laser lights are projected on the target to form a first line structured light stripe, the robot is controlled to move in a constraint mode so as to project the laser lights to another position of the target to form a second line structured light stripe, the camera respectively acquires images of two structured light stripes at two calibration positions, the relation of three-dimensional coordinate of points on stripe straight lines under a camera coordinate system at the two calibration positions is calculated, and thereby the structured light plane parameter calibration with the structured light stripe straight lines serving as calibration elements can be achieved.

The invention discloses a polyphaser system calibration method, comprising a calibration component which is formed by three or more signalized points with known geometry in rigid motion at the work area of the polyphaser system, obtaining a plurality of images of calibration and inputting the images to a computer, extracting image coordinate of the signalized points and regarding the image point which is shot by different cameras on the same signalized points on the calibration component at certain position as a group of corresponding points, linearly recovering the projection transformation matrix of every camera in the polyphaser system according to the geometry contained in the image corresponding points and the signalized points and utilizing nonlinearity arithmetic to optimize. The device disclosed by the invention comprises a calibration part, a handle, an operation system, a work area and a polyphaser system. The invention overcomes the shortages of low efficiency, having relatively large accumulated errors and the like in the existing calibration method which needs to calibrate the cameras in the polyphaser system one by one or step by step. Further, the invention realizes calibrating the whole polyphaser system at one-time, thereby having important practical engineering value.

The invention relates to a joint calibration method of a 3D lidar and a monocular camera, and belongs to the field of information fusion. The invention aims at improving the calibration efficiency under the requirement of ensuring the joint calibration accuracy of multi-sensor information fusion. Firstly, the monocular camera is calibrated, and then a normal vector of a target calibration plate in a monocular camera coordinate system, the distance from the target calibration plate to the origin in the monocular camera coordinate system, a normal vector of a fitting plane in a 3D lidar coordinate system and the distance from the origin to the fitting plane in the 3D lidar coordinate system are respectively solved at each position. Then, the results of the joint calibration are solved by using the distance correspondence principle. Finally, the result of the joint calibration is taken as the initial value into an optimization objective function to obtain the optimal joint calibration result. The joint calibration method of the invention greatly reduces human participation, reduces random errors caused by complicated man-made operation, simplifies the process of multi-sensor joint calibration and improves the precision of the calibration.

An accurate calibration method of micro inertia measuring unit by decoupling erection error angle (EEA)with scale factor includes setting up MIMU integral error model and separating couple between EEA of accelerometer and gyroscope and scale factor ,using position error canceling method to calculate out and to separate out scale factor and EEA of accelerometer as well as using least square method and iteration method to calculate out EEA of gyroscope and its relative error items in 10 position static calibration test and in 3 direction positive and negative rate test ,then using interpolation method to calculate out scale factor of gyroscope .

The invention relates to a binocular vision positioning method for target grabbing of an underwater robot, and belongs to the field of computer vision. The method is mainly used for accurately acquiring three-dimensional information of a grabbed target when an underwater robot works. The method comprises the following steps: double-target positioning: calculating internal and external parameters of left and right cameras; target detection: positioning a target object detection frame; binocular image correction: carrying out distortion correction and stereo correction, and determining a right image target area; binocular image stereo matching: extracting image feature points, describing the feature points, performing stereo matching, and removing mismatching; and calculating the three-dimensional information of the target in the image under the left camera coordinate. According to the method, the accurate parallax value is obtained by extracting feature points, removing unstable featurepoints through non-maximum suppression, constructing a binary descriptor, matching the feature points and removing mismatching. Through the scheme, the binocular stereo matching robustness can be improved, and meanwhile, the three-dimensional information of the detection target can be accurately obtained, so that the real-time positioning requirement on the target when the underwater robot grabsthe target is met.

According to the joint calibration method and device, the electronic equipment and the storage medium provided by the invention, the method includes: acquiring the point cloud data and the image dataacquired by the laser radar and the camera for the same target acquisition area, wherein the target acquisition area is internally provided with the target object capable of being used for calibration, and the target object comprises at least one corner point; determining a two-dimensional image coordinate and a three-dimensional point cloud coordinate of each corner point in the image data and the point cloud data respectively; according to the two-dimensional image coordinates and the three-dimensional point cloud coordinates of the same angular point, performing calculating to respectivelyobtain external parameters of the laser radar and the camera; performing joint calibration on the laser radar and the external parameters according to the external parameters of the laser radar and the camera. Therefore, the calibration of the laser radar and the camera is not carried out by using a calibration plate; insteadly, the point cloud data and the image data acquired by the laser radar and the camera aiming at the target object in the same target acquisition area are directly calibrated, so that the calibration efficiency is improved, the calibration process is simplified, and repeated calibration of the laser radar and the camera is facilitated.

The invention discloses a robust lens distortion correction method. The invention provides a method for separating lens distortion from camera parameters to be solved separately. The method comprisesthe following steps of: performing a feature extraction from a checkerboard calibration object by firstly performing angular point detection utilizing a Shi-Tomasi operator, then performing screeningaccording to the specific characteristics of symmetry and large variance of the checkerboard angular point, and finally obtaining an sub-pixel coordinate with accurate checkerboard angular point by utilizing a sub-pixel optimization algorithm; establishing a camera imaging model and a lens distortion model to obtain an optimized objective function with respect to a distortion parameter; and solving the distortion parameter by utilizing a nonlinear optimization algorithm for distortion correction. According to the robust lens distortion correction method, a calculation of all main distortion parameters can be accomplished with only one calibration object image containing the checkerboard, the model is simple, the calculation efficiency and stability are high, the application adaptability isgood in an industrial field, and the calculation accuracy is comparable to a traditional method.

The invention discloses a triaxial MEMS gyroscope rotation integral calibration method based on a uniaxial turntable. According to the invention, first, a triaxial MEMS gyroscope error model is established; the triaxial MEMS gyroscope is fixed on the uniaxial turntable; MEMS gyroscope six-position rotary calibration is carried out; test data and sampling time of 12 times of rotation of the MEMS gyroscope at the 6 positions are tested and recorded; through the 12 times of rotation of the MEMS gyroscope at the 6 positions, a MEMS gyroscope error model is simplified, and an error model after gyroscope rotation is obtained; integral calculations are carried out upon two sides of the equation of the error model after gyroscope rotation, an error equation set is established, and MEMS gyroscope error coefficient is obtained by calculation. With the method provided by the invention, calibration precision is ensured; and fixed zero bias, scale factor, cross-coupling error coefficient, and acceleration sensitivity coefficient of the MEMS gyroscope can be solved rapidly, such that calibration efficiency is improved.

The invention discloses a camera external parameter calibration method of a multi-camera system for solving the problems that a three-dimensional precise calibration object is difficult to manufacture, the efficiency of a multi-camera external parameter calibration process is low, and that accumulative errors are generated in the existing method. The method comprises the following steps: performing fitting to obtain quadratic curve matrixes of shooting ball projections of cameras; solving inhomogeneous coordinates of three spherical centers in a camera coordinate system; establishing a world coordinate system in which the three spherical centers are located on the same plane through the plane where the three spherical centers are located and the positions of the spherical centers; solving external parameters of a plurality of cameras in the world coordinate system in which the three spherical centers are located on the same plane, and accomplishing the external parameter calibration of the cameras in the multi-camera system, wherein the two coordinate systems are overlapped. By adoption of the camera external parameter calibration method disclosed by the invention, the external parameters of the plurality of cameras in the same world coordinate system are calculated quickly, conveniently and accurately without requiring more conversion, no accumulative error is generated, and the camera external parameter calibration precision is high. The camera external parameter calibration method is applied to the fields of image measurement, three-dimensional reconstruction, unmanned aerial vehicle navigation, etc.

The invention discloses a method for calibrating a camera shooting or photographing device, and belongs to the technical field of measurements. The method comprises the following steps of: presetting a position relationship between a calibration target and the camera shooting or photographing device; performing iterative computations according to coordinates of a preselected calibration point on the calibration target and a matching point of the calibration point on an actual image plane of the camera shooting or photographing device by utilizing an ideal lens imaging model, a lens distortion model and a collimation model; and calibrating the parameters of the camera shooting or photographing device. By the method, the position relationship between the calibration target and the camera shooting or photographing device is preset, the displacement calculation process of the optical center of the lens of the camera shooting or photographing device relative to the origin of coordinates of the plane of the calibration target is simplified, so that the whole calibration process is high-efficiency; and moreover, by the method, the problem that the parameters of the device are calibrated when the focusing is inaccurate can be effectively solved, the target pattern is only required to be photographed at one time, and the calibration efficiency is improved. In addition, the three-dimensional distance under the out-of-focus condition can be effectively measured.

The invention relates to a portable multifunctional vacuum calibration system and a method, belonging to the field of measurement technologies. The calibration system comprises a mechanical pump 1, a molecular pump 2, a first vacuum valve 3, a second vacuum valve 4, a third vacuum valve 8, a fourth vacuum valve 10, a fifth vacuum valve 11, a sixth vacuum valve 17, a seventh vacuum valve 19, an eighth vacuum valve 23, a ninth vacuum valve 15, a calibration chamber 5, a quadrupole mass spectrometer 6, a first small hole 9, a second small hole 20, a fine-adjustment valve 12, a gas source 13, a first vacuum gauge 14, a second vacuum gauge 18, a third vacuum gauge 21, a fifth vacuum gauge 24 and a pressure-stabilizing chamber 16; and the method comprises a vacuum leak calibration method and a vacuum gauge calibration method. According to the system, the vacuum gauges and a gas micro-flow calibration function are combined, and the vacuum gauges, vacuum leaks, leak detectors and gas micro-flowmeters can be calibrated in an on-site or on-line manner, so that the system has the characteristics of multifunction, high accuracy, little weight, small volume, portability and the like.

The invention relates to a correction method and device, in particular to an automatic gamma and white balance correction method and a device for a display device. The automatic gamma and white balance correction device comprises a display device, a color analysis meter, a PC (Personal Computer) and a test pattern generator which are sequentially connected electrically; the test pattern generator is electrically connected with the display device through a driving IC (Integrated Circuit). According to the automatic gamma and white balance correction device, whether the quadratic sum of difference between luminance values under different gray levels and target luminance values satisfies an error range or not is judged, correction is finished after solidification of gamma register parameters in a gamma register of the driving IC, the gamma register parameters are modified if not, and recalibration is performed until the quadratic sum of the difference between the luminance values and the targeted luminance values satisfies the error range; a calibration result is automatically judged after calibration of gamma and white balance and the calibration result is not influenced by subjective judgment of tested person.

The application discloses an LED display device and a driving method thereof. The LED display device comprises a plurality of LEDs serving as pixel units. The method includes: gray scale data are generated according to a display image; according to a practical frame rate and a practical refreshing rate, a practical gamma table is generated; on the basis of the practical refreshing rate, gamma correction is carried out on the gray scale data to obtain display data; a PWM signal is generated based on the display data; and a constant-current source is controlled to provide a driving current by using a PWM signal, so that LEDs are lightened to generate brightens corresponding to a gray scale. According to the method, the practical gamma curve is generated based on the practical frame rate and the practical refreshing rate, thereby improving an effect of gamma correction.

The invention discloses a method and device for jointly calibrating the parameters of a visible light camera and an infrared camera. The method comprises steps of: detecting the edges of a visible light image and an infrared image to obtain a visible light edge image and an infrared edge image; acquiring at least four groups of matched point pairs of the visible light edge image and the infrared edge image by using a scale invariant feature transform (SIFT) algorithm; and determining an extrinsic parameter matrix according to the at least four groups of matched point pairs, the intrinsic parameter matrix of the visible light camera, and the intrinsic parameter matrix of the infrared camera. The method and the device may acquire the matched point pairs in the visible light edge image and the infrared edge image without a calibration board and determine the extrinsic parameter matrix without the calibration board so as to reduce the calibration cost of camera parameters. Further, when a focal length of the camera is changed, the extrinsic parameter matrix can be determined without camera position adjustment so that parameter calibration efficiency is increased.

The invention discloses a calibration method for the transmitted power of a digital microwave transceiver. The calibration method comprises the following steps of first generating a transmitted power calibration table according to transmitted power control voltages and actual radio frequency transmitted power which corresponds to the transmitted power control voltages and is transmitted by the microwave transceiver, second generating a channel calibration table, and thirdly correcting the transmitted power control voltage value in the transmitted power calibration table by using a channel correcting method. The invention further discloses a calibration circuit for achieving the calibration method for the transmitted power of the digital microwave transceiver. The calibration circuit comprises a microwave unit and a monitoring unit, and the microwave unit comprises a first power detection tube, a second power detection tube, a microwave amplifier and a microwave attenuator. The calibration circuit has the advantages of being high in batch production efficiency, high in calibration rate, high in transmitted power stability, simple in calibration method and the like.

The invention relates to a grain storage quantity detection method for horizontal warehouses and shallow silos. The grain storage quantity detection method comprises the following steps of: firstly selecting specific pressure sensors to lay a grain warehouse pressure sensor detection network; distributing the pressure sensors along the side wall of the grain warehouse in the mode that all the pressure sensors are evenly-spaced laid at d meter distance from the side wall; and determining whether a grain warehouse is calibrated or not so as to obtain a calibration parameter and a grain warehouse weight prediction model, spreading the top surface of a grain pile in the grain warehouse after the grain warehouse is fully filled with the grain, detecting the average output valve of the pressure sensor at the bottom of the grain warehouse, and detecting the grain storage quantity of the grain warehouse according to an actually-tested bottom surface area of the grain warehouse, a bottom surface area of the calibrated grain warehouse and calibrated parameters by using a model so as to obtain an estimated value of the weight of the grain warehouse. According to the grain storage quantity detection method provided by the invention, the pressure sensors are required to be arranged on the bottom surface of the grain warehouse, and a compensating item of a side grain warehouse friction action is added into a bottom surface pressure estimating model in order to avoid using the side pressure sensor and accurately obtain the estimated value of the pressure of the bottom surface of the grain warehouse, so that the quantity of the sensors is obviously reduced, and the device detection cost and the installation and maintenance cost are reduced.

The invention relates to a fast calibration method of a single-phase electric energy meter. According to the fast calibration method, the gain initial value of a power gain correction register of a metering chip of a calibrated meter is preset so as to be fast positioned to a target error value, only a 100%Ib-point 0.5-induction error point is debugged; apparent power deviation and active power deviation are simultaneously obtained at the error point; 100%Ib-point 1.0-resistance gain correction is performed through utilizing the apparent power deviation; 100%Ib-point 0.5-induction phase correction is performed through utilizing the active power deviation; and a 100%Ib-point 0.5-induction error value which has been obtained through calculation is directly utilized to perform 5%Ib-point 1.0-resistance small signal correction, and therefore, too long debugging time of small signals can be avoided. The fast calibration method has the advantages of fast error target value positioning, high meter calibration efficiency and significantly-improved accuracy.

The invention discloses a calibration system of a temperature sensor chip, which comprises a test board and a temperature calibration system, wherein the test panel is provided with a temperature sensor reference chip and a chip to be calibrated; and each chip is connected and communicates with the temperature calibration system through a unified digital interface. The temperature calibration system reads the temperature values of various calibration chips and reference chips through the unified digital interface; and various chips to be calibrated simultaneously acquire the data, thereby realizing synchronous acquisition and calibration of multichip data, greatly improving the acquisition efficiency of the data and reducing the test and calibration time of the chips and calibration cost. The invention has the advantages of simple structure, easy building, short calibration time, high calibration efficiency, low cost, high degree of automation and the like. The invention also discloses a calibration method of the temperature sensor chip.

The invention discloses an error processing method of the output signal of an optical-fiber scopperil component and belongs to the error processing methods of the output signal of an optical-fiber scopperil component in an inertial navigation system. The concrete steps of the processing method are that: an output signal model of the optical-fiber scopperil component and an error model thereof are built; the marking and the compensation of the fixed error of the optical-fiber scopperil component are implemented; the self-adaptive filtering of the random error of the optical-fiber scopperil component is implemented. The processing method effectively reduces the zero-offset drift of the optical-fiber scopperil component which is caused by temperature changes, has high marking precision of the fixed error, high marking efficiency and good adaptability; furthermore, the processing method effectively reduces the random error of optical-fiber scopperil, has small amount of computation, and is suitable for real industrial applications.