88 results about "Transformation equation" patented technology

A system is disclosed for warping models made from geometric objects, such as electronic maps, to correct local distortions in the models without compromising model topology. A set of transformation functions are derived from relationships between points in a first model that match points in a second model. The transformation functions are then applied to the points in the first model to generate a new model with reduced distortion. In order to provide for reducing local distortions, warping is applied to selected corresponding regions of the first model and the second model by triangulating these regions and generating transformation functions for each corresponding pair of triangles. Topology preservation is achieved by identifying matching points in the first model and the second model that have a potential for causing topology deviations. Such matching points are then excluded from the process of developing transformation equations to be used in the warping process. Matching points with potential for causing topology deviations are identified by triangulating matching points in the selected regions of the first model and the second model and analyzing the resulting triangles.

A secret key registration system which registers a secret key in a portable key device and vehicle. A first transformation equation is stored in a writer and the vehicle. A second transformation equation is stored in the portable key device and the vehicle. The writer transmits a registration code to the portable key device and generates intermediate data with the first transformation equation of the writer. The intermediate data is transmitted to the portable key device, which generates the secret key from the intermediate data with the second transformation equation. The portable key device transmits the registration code to the vehicle. The vehicle generates intermediate data from the registration code with the first transformation equation of the vehicle, and then generates the secret key from the intermediate data with the second transformation equation.

The invention relates to an online offset correction method and device for robot hand-eye calibration. The online offset correction method comprises the steps that coordinate values of the circle centers of nine circles on a calibration plate in a camera coordinate system and a base coordinate system are obtained; a transformation equation of the circle center of each circle on the calibration plate from the camera coordinate system to the robot base coordinate system is established, through offset coordinates of each circle, the least square method is adopted to calculate a homogeneous transformation matrix of the camera coordinate system relative to the robot base coordinate system; and according to calibrated pose values of the camera coordinate system relative to the base coordinate system, errors of the offset correction calibration results of the nine circles on the calibration plate are analyzed through a vector two-norm formula, and thus the precision of the online offset correction method is evaluated. According to the online offset correction method and device for robot hand-eye calibration, offset in the robot hand-eye calibration process is corrected, flexible, preciseand rapid adjustment on a production line can be achieved, high-repeatability and precise grabbing operation can be achieved, the online offset correction method and device can be applied to operationof an SCARA robot hand-eye device, and the simple, efficient and high-precision effects are achieved.

The invention discloses a battery capacity predicting device and a battery capacity predicting method. A battery pack is built in or externally connected with the battery capacity predicting device. The battery capacity predicting device comprises a battery capacity algorithm equation. A data base is memorized by means of a microprocessor executing equation and memorized in an overwriting non-volatile memorizer. An open loop voltage meter, a current gain meter and a capacity transformation equation are built in the data base. A predicted battery discharge curve is calculated according to measured load current and battery temperature by means of the battery capacity algorithm equations, and then the data base is amended according to a coulombmeter, the battery discharge curve and battery terminal voltage.

The invention discloses a method for measuring a relative pose of a noncooperative target. The method comprises the steps: selecting an object to be measured with equilateral triangle characteristics as the noncooperative target, and establishing a single line structured light based visual measurement system model; extracting three straight lines of the object to be measured and crossing points between single line structured light and the object to be measured, so as to obtain coordinates of five characteristic points of the object to be measured in an image coordinate system; carrying out calculation according to geometric constraint conditions of the object to be measured, so as to obtain coordinates of the five characteristic points of the object to be measured in a camera coordinate system; carrying out calculation according to distance translation invariance and the geometric constraint conditions of the object to be measured so as to obtain coordinates of the five characteristic points of the object to be measured in a world coordinate system, substituting the coordinates into a transformation equation of the camera coordinate system and the world coordinate system, and carrying out solving, so as to obtain the relative pose of the object to be measured, i.e., the relative pose of the noncooperative target. According to the method, through increasing an auxiliary line structured light source to monocular vision, the measurement on the relative pose of triangular characteristics of unknown dimensions is achieved.

The invention discloses an indoor passive navigation and positioning system and an indoor passive navigation and positioning method. The system comprises a depth camera Kinect, an inertial navigator and an identifier, wherein the Kinect and the inertial navigator are connected with an industrial personal computer SBC84823; the identifier is independently stuck on a wall; the Kinect obtains image data and depth data of the identifier; the inertial navigator is used for transmitting the depth data and the image data into the industrial personal computer SBC84823 through a USB interface after determining a self attitude angle; and the coordinate position of a robot (Kinect) is calculated by the industrial personal computer SBC84823. The method comprises the following steps: firstly, identifying a world coordinate of the identifier in an image according to a digital identification technology and calculating a relative coordinate relative to the robot (Kinect) of the identifier; and then, forming a transformation matrix by the self attitude angle of the robot determined by the inertial navigator and a coordinate to be solved of the robot to obtain a transformation equation; and solving the self coordinate of the robot according to the equation. The embodiment of the invention is mainly used for detecting and calculating the coordinate position of the robot in the image.

A color correction method is provided. Grey values of three primary colors of an image data are transformed into initial characteristic values in a color space. Three sets of characteristic values of a to-be-corrected apparatus when the apparatus displays the primary colors respectively are measured. The characteristic values of the image data are transformed into a set of adjusted brightness values of the primary colors according to the characteristic values and a color space transformation equation. Gamma curves of the apparatus when displaying the primary colors are measured and modified to generate new grey-value vs. brightness relationships for the primary colors, so as to obtain adjusted grey values of the primary colors corresponding to the adjusted brightness values.

The invention relates to a color correction method, which comprises the following steps: converting a tricolor gray-scale value of image data into a characteristic value of a color space; regulating the characteristic value according to the relationship of a coordinate position of standard white light defined by the color space and a coordinate position of the characteristic value defined in the color space, and the tricolor gray-scale value so as to generate a regulated characteristic value; measuring three characteristic values of tricolors respectively displayed on a device to be corrected; converting the regulated characteristic value into a brightness value after tricolor regulation according to the three characteristic values of the device to be corrected and a color space transformation equation; and measuring gamma property curves of tricolors respectively displayed on the device to be corrected, and modeling a respective gamma property curve of the measured tricolors to generate a respective new relationship of the gray scale and the brightness of the tricolors; therefore, a gray-scale value of the tricolors after regulation corresponding to the brightness value of the tricolors after regulation is acquired.

On conversion of a distorted circular image photographed by use of a fisheye lens to a planar regular image, parameter setting is performed by a user's intuitive manipulation to relieve the operation load. A dome-shaped virtual sphere H is defined on a distorted circular image S on the XY plane, and a user is allowed to designate a cut-out center point P (x0, y0) and an auxiliary point Q (x1, y1) on the distorted circular image S. An intersecting point G (x0, y0, z0) immediately above the point P is determined, and a UV plane is defined on a tangent plane S2 with respect to the virtual sphere H. An angle φ formed between the U axis and the X axis is determined on the basis of an angle θ formed between a reference straight line J passing through two points P, Q and the X axis. Transformation equations based on the orthogonal projection method including the coordinate values x0, y0, z0 and the angle φ as parameters are utilized to allow the coordinates (u, v) to correspond to coordinates (x, y), a distance between the two points P, Q is given as a conversion magnification m, thereby a part in the vicinity of the point P of the distorted circular image S is converted to a plane regular image on the UV plane.

The invention discloses a tool path generating method for a multi-axis machining complex curved surface of a constraint circular tool based on the motion of a machine tool. The method explains by taking head and table five-axes numeric control machine tools as an example and comprises the following steps: firstly, establishing a relation equation between a tool position design variable and tool position data as well as a motion transformation equation between the tool position data and a rotating shaft of the machine tool, and further deducing a relation equation between the tool position design variable and the rotating shaft of the machine tool; secondly, analyzing and discussing the equations, and deducing a formula of solving another two variables by using any two variables in a known equation set, thereby obtaining a tooth position calculation formula for the multi-axis machining complex curved surface of the constraint circular tool; on the basis, giving out the basic principle and the calculation flow of a tooth path generation algorithm for the multi-axis machining complex curved surface of the constraint circular tool. The test result shows that by using the algorithm, great change of the rotating shaft of the machine tool can be avoided, the feed speed of a motion shaft of the machine tool is improved, and higher processing quality of the curved surface can be obtained; the algorithm has certain actual application value.

The invention relates to a method for robot hand-eye calibration. A calibration plate provided with a calibration point is fixed at the tail end of a robot. The calibration method comprises the following steps that pose information of a tool center point of the robot in a robot base coordinate system is acquired, and the pose information is converted into a dual quaternion form to obtain hand movement spiral information; image information of the calibration plate is acquired, coordinate information of the calibration point in a camera coordinate system is calculated according to the image information, and the coordinate information is converted into a dual quaternion form to obtain eye movement spiral information; a movement transformation equation between the hand movement spiral information and the eye movement spiral information is established, and matrix factors of the movement transformation equation are extracted; a plurality of matrix factors of the robot in different poses areacquired, a transformation matrix is constructed according to each matrix factor; and each transformation matrix is subject to singular value decomposition to obtain a unit dual quaternion of the robot base coordinate system relative to the camera coordinate system. The method has the advantages of being high in calibration speed and simple in calculation.

The temperature (T) of a metal (1) can be influenced directly or indirectly by at least one actuator (2) which is actuated in accordance with a control variable (S). The control variable (S) and starting values (TA, p1A, p2A) for a temperature of the metal (1) and phase proportions in which the metal (1) is at least in a first phase or a second phase, respectively, are predetermined for a material model (5). A heat conduction equation and a transformation equation are solved in real time within the material model (5), taking account of these variables (TA, p1A, p2A) , and in this way expected values (TE, p1E, p2E) are determined for these variables. As part of the transformation equation, the Gibbs' free energies (G1, G2) of the phases of the metal (1) are determined, a transformation rate of the metal (1) from the first phase to the second phase is determined therefrom, and the expected proportions (p1E, p2E) are determined from the latter.

The invention discloses an automated projection-keyboard calibration method of utilizing four manually selected points, and aims to solve the problem that larger calibration errors of current calibration methods exist. According to the method disclosed by the invention, firstly, a recognition camera is utilized to shoot a picture of an LED calibration board, and an internal parameter matrix of therecognition camera and distortion coefficients of a distortion model are calculated; then the calibration reference points of a projection keyboard are manually selected, and image coordinates of thecalibration reference points are calculated; a relative position relationship of the recognition camera and the projection keyboard is calculated according to a camera imaging model, and world coordinates of the calibration reference points are determined; a transformation equation of the calibration reference points from a camera coordinate system to a world coordinate system is established according to a projection transformation relationship, and a projection transformation matrix is obtained; and then world coordinates of each key are calculated according to a projected-keyboard size andthe world coordinates of the four calibration reference points, and a keyboard table is generated. The method is suitable for use in automated projection-keyboard calibration.

The invention discloses a method for measuring attosecond X-ray impulse strength and chirp time distribution and application thereof. According to parametric calculation formulas, relative laser phase of each measured photoelectron can be determined by the photoelectron spectrums acquired from measurement of two different laser strengths, and shape and specific time structures of impulse, including impulse strength and chirp time distribution, are reconstructed by the spectrum analysis technology of the transformation equations of the photoelectron spectrums. Without a great quantity of time-resolved measurement of the photoelectron spectrum or tedious iterative computation or test data fitting process, the method can assist in reconstructing time-domain characteristics of the attosecond X-ray impulse from the two photoelectron spectrums acquired by measuring. Measurement results of the method, serving as reference data, can be used for researching, analyzing, evaluating and optimizing technical parameters and property indexes of the attosecond X-ray impulse light source, and can be used for researching and analyzing relative information varies along with time during the process of superfast reaction dynamics.

The invention provides a cutter axis vector interpolation method in 5-axis numerical control machining with rotation axis angular velocity smoothness characteristic being taken into consideration and belongs to the technical field of 5-axis numerical control machining. The method solves the problem of refining interpolation of cutter axis vector at the place of an ordinary cutter location point according to key cutter location set based on cutting property and cutter feasible space. The method is characterized by, to begin with, calculating the rotation angle of each rotation axis corresponding to the key cutter axis vector under a machine tool coordinate system according to an inverse kinematics transformation equation; providing an approximation calculation formula of angular velocity of each rotation axis at the place of each refining interpolation cutter location point by utilizing a finite difference method; then, establishing a least square optimization objective function with the minimum angular velocity change of each rotation axis being an objective, and giving a solving method to obtain the rotation angle of each rotation axis at the place of the refining interpolation cutter location point; and finally, carrying out forward synthesis to obtain cutter axis vector at the place of the refining interpolation cutter location point. The method enables the angular velocity change of each rotation axis to be minimum and smooth and steady, thereby improving kinematics and dynamics performances of a five-axes numerical control machine tool in the process of machining parts of complex surfaces.

A calibration method for merging object coordinates and a calibration board device using the same are provided. The calibration board device has a plurality of characteristic points and a central reflection element. A center of the central reflection element has a central characteristic point. A distance sensor emits a distance sensing signal to the central reflection element, so as to obtain a central real coordinate. Intrinsic and extrinsic parameters of a camera is used to establish a transformation equation which transforms the central real coordinate into a central image coordinate. Finally, a calibration image of the calibration board device is retrieved, and the central characteristic point is searched, and the central image coordinate is projected on the calibration image whereby the central image coordinate is calibrated to aim at the central characteristic point on the calibration image, thereby generating extrinsic and intrinsic parameter parameters calibrated.

A projection keyboard real time dynamic automation calibration method relates to a projection keyboard automation calibration method, and aims to solve the problems that an existing calibration method is large in calibration errors; the method comprises the following steps: using an identification camera to take a LED calibration board image, and calculating an internal parameter matrix of the camera and a distortion coefficient of a distortion model; projecting the projection keyboard on a movable plane, calibrating the relative position relation between the camera and the projection keyboard in real time, and calculating image coordinates of calibration reference points; using the projection keyboard to calculate the relative position relation between the camera and the projection keyboard and determining world coordinates of the calibration reference points; building a transformation equation of the reference points transforming from the camera coordinates to the world coordinate system according to a projection transformation relation, thus obtaining a projection transformation matrix; calculating world system coordinates of each button according to the projection keyboard sizes and the calibration reference point world coordinate system. The method is applied to the projection keyboard automation calibration.

A projection system and an image processing method thereof are provided. The system includes a projector module, a photography module and a processing module. The projector module projects a first image frame to an object surface. The photography module photographs the object surface to derive a second image frame including the first image frame and an indication point, wherein the indication point is formed by light projected on the object surface by an external device. The processing module analyzes the second image frame to derive coordinate of the indication point in the second image frame, derives coordinate of at least a feature point of the first image frame in the second image frame according to a linear-approximation method, and transforms the coordinates of the indication point in the second image frame to the coordinates in the first image frame by using two-dimensional coordinate transformation equations.

The invention relates to a globoidal indexing cam modeling method based on Creo. The modeling method includes the steps that a movable coordinate system and a fixed coordinate system of a globoidal indexing mechanism are created; according to an intermittent movement rule and the meshing principle of the globoidal indexing cam and an indexing disc, an RPY transformation matrix of meshed points iscreated; a matrix transformation equation is created and figured out to obtain Descartes coordinate values of the meshed points in the fixed coordinate system; according to the obtained spacial coordinate values of the meshed points, a globoidal indexing cam modeling program is coded in the Creo software, and meshing curves are drawn; matching is conducted on the curves separately, and a real cambody is modified and filled to obtain a three-dimensional globoidal indexing cam model. According to the technical scheme, by adopting the powerful CAD curve modeling function of the Creo software, the accurate globoidal indexing cam modeling method is implemented and can substantially improve the design efficiency and accuracy of the globoidal indexing cam.

An image data processing method for sharpening a captured image; the method defines a first transformation equation to change the pixel values of a defocused image into a focused image using the coordinates of the defocused image and the focused image as arguments, calculates a DetailedFocus function from the optimal solution of the first transformation equation by giving the pixel values of the focused image and the defocused image as educational data, extracts a predetermined number of important points on the DetailedFocus function, defines a second transformation equation to change the pixel values of the important points of a defocused image into a focused image using the coordinates of the defocused image and the focused image as arguments, calculates a SmartFocus function from the second transformation equation, and produces a focused image from a defocused image using the SmartFocus function.

The invention discloses a method for measuring attosecond X-ray pulses and application of the method. According to the method disclosed by the invention, each measured related phase of a photoelectron is determined by using a parameterized computing formula, and the shape of a pulse and a concrete time structure are rebuilt through one step by using an analytical photoelectron spectrum unscrambling technology; and the time domain characteristics of the attosecond X-ray pulses can be rebuilt from each measured photoelectron spectrum without a large amount of time resolution measurements of a photoelectron spectrum and without a redundant iterative computation and an experimental data fitting process. The time uncertainty of a pulse measurement result is computed from energy bandwidth values of the pulses by using the parameterized formula. Because a direct relation among attosecond pulse time characteristics, important laser parameters (such as peak strength, electric field envelope shape, phase, carrier-envelope phase and the like), atomic or molecular ionization power and the photoelectron spectrum is established by a transformation equation, the method can be used for computing unknown parameters from each known parameter value.

A method for mapping an input grayscale into an output luminance includes selecting a first reference grayscale, a first reference luminance, a second reference grayscale and a second reference luminance according to an input grayscale, generating a middle reference grayscale and a middle luminance, replacing a value of the first or second reference grayscale by a value of the middle reference grayscale, and replacing a value of the first or second reference luminance by a value of the middle luminance according to the middle reference grayscale and the input grayscale, and generating an output luminance by computing a linear transformation equation.

The invention discloses a processing cutter shaft vector fairing method of an annular cutter based on a BC type five-axis numerical control machine tool. The method comprises the following steps that a relation equation between a cutter shaft vector and a cutter position design variable of the annular cutter is established; a movement transformation equation between the cutter shaft vector of the annular cutter and the rotation axes B and C of the five-axis numerical control machine tool is established; a relation equation between the cutter position design variable of the annular cutter and the rotation axes B and C of the five-axis numerical control machine tool is established; a design vector, an objective function and a constraint condition of cutter shaft vector faring of the annular cutter are determined, and a mathematical model of processing cutter shaft vector fairing of the annular cutter based on the BC type five-axis numerical control machine tool is established; and a solving method of the mathematical model of utter shaft vector fairing is determined. The method can avoid rapid change of the rotation axes of the machine tool, rotation-axis movement of the machine tool is more stable and smoother, the angular velocity and angular acceleration of the rotation axes of the machine tool are reduced greatly, the curved surface processing quality and efficiency are improved, and the practical application value is higher.

An image processing method includes a step of obtaining an input image, and a transformation step of performing multiple image transformations including multiple geometric transformations. The transformation step includes calculating correspondences between image coordinates of the input image and image coordinates of the output image based on multiple coordinate transformation equations corresponding to geometric transformations, then defining pixel values of the corresponding output image based on pixel values of the input image, and interpolating space pixels of the output image that do not have corresponding pixels in the input image once for each space pixel.

The invention provides a method for monitoring dynamic deflection of a bridge based on optimized arrangement of an inclinometer, and the method comprises the following steps of establishing an inclination-dynamic deflection transformation equation, simulating a vehicle-passing-bridge condition in a bridge finite element model, extracting the inclination time-history data of inclinometer laying candidate nodes and the displacement time-history data of the bridge key cross-sections as a data set for genetic algorithm optimization training, using the information entropy as a fitness function in the optimization process to obtain the optimal laying positions of the inclinometer with a fixed number and the corresponding information entropy, determining a critical information entropy by taking the relative error equal to 5% of the time-history displacement of the bridge key cross-sections in the predicted finite element model, finding the minimum less than or equal to the number of sensors of the critical information entropy from the information entropies corresponding to the number of the respective sensor in the optimal arrangement of the inclinometer as the number of the optimal sensors, and determining the optimal laying position corresponding to the number of optimal sensors as the laying position of the inclinometer. The method can accurately predict the dynamic deflection of the bridge.

The invention discloses a multi-dimensional multi-phase multi-process coupling analog method of activated sludge sewage treatment. According to the -dimensional multi-phase multi-process coupling analog method, based on a multi-phase flow theory, activated sludge used as a solid phase, a gas phase (bubbles) aerated in an activated sludge system and a liquid phase (sewage) form a three-phase composite system, a sludge-water-gas movement characteristic and an interphase physical function in a sewage treatment system are reasonably described by adopting a multi-phase flow movement equation; and meanwhile, an oxygen mass transfer equation and a pollutant migration and transformation equation are further combined, and a distribution characteristic of dissolved oxygen in a system, a migration and transformation characteristic of pollutants and an interphase biochemical action characteristic are accurately predicted. By adopting a coupling model disclosed by the invention, the part of an activated sludge system, at which sludge easily deposits, and effluent quality conditions under different working conditions can be quantitatively predicted, and the great significance is achieved for the maintenance of normal operation in a sewage treatment plant.

On conversion of a distorted circular image photographed by use of a fisheye lens to a planar regular image, parameter setting is performed by a user's intuitive manipulation to relieve the operation load. A dome-shaped virtual sphere H is defined on a distorted circular image S on the XY plane, and a user is allowed to designate a cut-out center point P (x0, y0) and an auxiliary point Q (x1, y1) on the distorted circular image S. An intersecting point G (x0, y0, z0) immediately above the point P is determined, and a UV plane is defined on a tangent plane S2 with respect to the virtual sphere H. An angle φ formed between the U axis and the X axis is determined on the basis of an angle θ formed between a reference straight line J passing through two points P, Q and the X axis. Transformation equations based on the orthogonal projection method including the coordinate values x0, y0, z0 and the angle φ as parameters are utilized to allow the coordinates (u, v) to correspond to coordinates (x, y), a distance between the two points P, Q is given as a conversion magnification m, thereby a part in the vicinity of the point P of the distorted circular image S is converted to a plane regular image on the UV plane.

The invention belongs to the field of the radar array antenna signal processing technology and discloses a subarray dimension reducing method for a radar three-dimensional conformal array. The method can be used for various three-dimensional conformal arrays with rotation axes, wherein the various three-dimensional conformal arrays include frustum arrays, cylinder or semi-cylinder arrays, spherical arrays and the like. According to the method, firstly, subarray division is performed on the radar three-dimensional conformal array; secondly, the three-dimensional rotation transformation equation is used for adjusting the beam pointing directions of all subarrays; finally, a dimension reducing matrix is calculated. According to the subarray dimension reducing method for the radar three-dimensional conformal array, the beam pointing directions of all the subarrays can be correspondingly adjusted according to three-dimensional rotation of all the subarrays, and therefore the purpose that the beam pointing directions of the whole array face are still the same after dimension reducing is achieved.

The invention discloses a cutter-axis vector smoothing method based on AB-type five-axis numerical control machine tool ball-end cutter machining. The method comprises the following steps: establishing a relation equation between ball-end cutter cutter-axis vectors and cutter-location design variables; establishing a motion transformation equation between the ball-end cutter cutter-axis vectors and five-axis numerical control machine tool rotation shafts A and B; establishing a relation equation between the ball-end cutter cutter-location design variables and the five-axis numerical control machine tool rotation shafts A and B; determining a design variable, an objective function and constraint conditions of ball-end cutter cutter-axis vector smoothing, and establishing a cutter-axis vector smoothing mathematical model based on the AB-type five-axis numerical control machine tool ball-end cutter machining; and determining a solving method of the cutter-axis vector smoothing mathematical model. The method can prevent dramatic changes of the machine tool rotation shafts to enable the machine tool rotation shafts to be able to operate more smoothly and stably, and angular velocity and angular acceleration of the machine tool rotation shafts are greatly reduced, so that machining quality and machining efficiency of a curved surface are improved; and the method has a higher practical application value.

The invention discloses a large screen fusion projection method comprising steps of: constructing a 3D model of a scaled-down exhibition hall by using a D modeling method and establishing an exhibition hall local 3D coordinate system; splicing the projection images of multiple projectors into a whole projection image by using an image splicing method and storing a whole projection image effect picture of a scaled-down whole projection image; simulating an effect model, projected onto a parallel screen, of the whole projection image effect picture by using a parallel projection method; acquiring control points on an annular screen, homonymous points, corresponding to the control points, on the effect model, and pixels on the whole projection image effect picture; computing a third transformation equation based on the control point coordinate values, homonymous point coordinate values, and pixel coordinate values; performing transformation computation on the real projection image according to the third transformation equation in order to project each pixel of the projection image into a correct position on the annular screen, thereby finishing geometric correction of a large screen projection image.