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38 results about "Plane equation" patented technology

Plane Equation. The equation of a plane in 3D space is defined with normal vector (perpendicular to the plane) and a known point on the plane. Let the normal vector of a plane, and the known point on the plane, P 1.

Route planning method and system for corner optimization

The invention discloses a path planning method and system for corner optimization. The method and system are used for cutter radius compensation and machining instruction smooth transition of a three-dimensional path of a numerical control machine tool. The method comprises the steps that a machining instruction is pre-read, and a path point location is analyzed; calculating a path direction vector and a normal vector, and determining a path plane equation; calculating a plane included angle and an intersection direction vector through a normal vector; generating a compensation curve by translating along the perpendicular direction of the intersecting line by taking the radius of the cutter as a constraint; and generating a smooth control instruction through curve subdivision and inserting the instruction into an instruction queue. The problem that three-dimensional path corner transition is not smooth is solved, the machining precision and efficiency are remarkably improved, and the method is suitable for a numerical control machine tool for complex curved surface machining.
Owner:NANJING LANHAO INTELLIGENT TECH CO LTD

Welding seam identification method of non-planar structural member, medium and equipment

The invention relates to a welding seam identification method for a non-planar structural member, and the method comprises the steps: collecting a workpiece surface point cloud, segmenting the workpiece surface point cloud to obtain a bottom plate region point cloud and a rib plate region point cloud, carrying out the plane fitting of the bottom plate region point cloud, obtaining a search vector and a plurality of plane equations, and dividing each plane equation to obtain a plane region and a curved surface region; and constructing a rib plate plane equation according to the search vector, projecting the rib plate region point cloud to the rib plate plane equation to obtain a bottom plate boundary point cloud, fitting a straight line for the bottom plate boundary point cloud in the plane region or / and performing vector analysis on the bottom plate boundary point cloud in the curved surface region to obtain welding seam points, and sequencing the welding seam points to obtain a welding seam track. The problems that in the prior art, in a complex non-planar structure, the welding seam position cannot be efficiently and accurately recognized, and consequently the welding efficiency and quality are low are solved.
Owner:SPEEDBOT ROBOTICS CO LTD

Container positioning method, system and device based on laser radar and storage medium

The invention provides a container positioning method, system and device based on a laser radar and a storage medium, and the method comprises the steps: obtaining first point cloud data covering a container and a loading and unloading platform, carrying out the iterative fitting of the first point cloud data through an RANSAC algorithm, obtaining plane equations corresponding to a plurality of dominant planes of the segmented container, and carrying out the calculation of the plane equations, calculating a current pose of the container in the reference coordinate system according to a plane equation of the plurality of dominant planes, and determining a first pose parameter; in the moving process of the container or the loading and unloading platform, second point cloud data obtained by scanning the tail environment of the container are obtained, local feature extraction and clustering filtering are conducted on the second point cloud data through an eight-neighborhood image algorithm to determine the tail position of the container, the first pose parameter is corrected according to the tail position of the container, and the tail position of the container is obtained. And outputting the second pose parameter of the container. According to the invention, multiple laser radars are matched, the real-time performance of scanning detection and the integrity of point cloud are ensured, and the precision and efficiency of container pose measurement are improved.
Owner:GUANGZHOU DUGE TECH CO LTD

Three-dimensional large component assemblability evaluation method based on point-surface fusion

The invention belongs to the technical field of integrated control, and particularly relates to a three-dimensional large component assemblability evaluation method based on point-surface fusion, and the method comprises the following steps: arranging fixed feature points on the surface of a three-dimensional large component, and numbering the fixed feature points; establishing a global coordinate system, and obtaining coordinate values of the feature points; constructing a plane equation of a plane; calculating a plane normal vector formed by the three points; solving an included angle formed by the normal direction vector; obtaining theoretical coordinate values of the corresponding feature points in a digital model; solving a plane direction vector of the three-dimensional large component; solving an included angle formed by all normal direction vectors; performing comparison processing on the theoretical plane normal direction vector and the actually measured plane normal direction vector included angle; if the error tolerance requirement is met, assembling is successfully achieved. According to the method, the measurement efficiency is improved by arranging the fixed measurement feature points, the point location data can be detected by the laser tracker only through scanning, and the working efficiency is improved.
Owner:CHENGDU AIRCRAFT INDUSTRY GROUP

A linearization method for the output function of a hydropower station based on a simplified constraint strategy

This invention provides a method for linearizing the power output function of a hydropower station based on a simplified constraint strategy. The method includes: equally dividing the feasible region of the power output function into rectangular grids; defining a corresponding plane for each rectangular grid; constructing a quadratic programming model for calibrating the plane cluster parameters that approximate the power output surface of the hydropower station based on the characteristic parameters of the planes and the simplified plane set corresponding to the rectangular grids generated using the simplified constraint strategy; solving the quadratic programming model to obtain a set of plane equation parameters that approximate the optimal power output of the hydropower station; and in a reservoir optimization scheduling model where the scheduling objective includes maximizing the power output or power generation of the hydropower station within the scheduling period, using the parameters of the solved plane equations to construct a linearized expression for the hydropower output function in the reservoir optimization scheduling model. This invention avoids introducing integer variables, reduces the size of the quadratic programming model while ensuring the accuracy of fitting the hydropower station's power output, and greatly improves the solution efficiency.
Owner:CHINA YANGTZE POWER +1

Demonstration-free vertical welding seam identification method, medium and equipment

The invention relates to a teaching-free vertical weld joint identification method, medium and equipment, and the method comprises the steps: collecting the surface point cloud of a to-be-welded workpiece, determining a bottom plane equation according to the surface point cloud of the to-be-welded workpiece to obtain upper surface feature points, carrying out the linear fitting of the upper surface feature points to obtain a plurality of linear equations, and obtaining the inner points of each linear equation; constructing an optimized feature point cloud, carrying out vector analysis on the optimized feature point cloud to obtain a plurality of welding seam end points, obtaining intersection points of points in each linear equation, determining a welding seam type according to the welding seam end points, projecting the intersection points of the points in each linear equation to a bottom plane equation to obtain a plurality of vertical welding seams, and obtaining a plurality of vertical welding seams according to the intersection points of the points in each linear equation and the welding seam end points. And determining the orientation of each vertical welding seam to complete welding seam identification. The problems that in the prior art, computing resource consumption is high, adaptability and generalization ability in practical application are insufficient, and recognition accuracy and recognition efficiency are low are solved.
Owner:SPEEDBOT ROBOTICS CO LTD

A method, system, and media of a lightweight indoor 3D laser ground extraction algorithm

The application discloses a lightweight indoor 3D laser ground extraction algorithm method, system and medium. The method comprises the following steps: acquiring indoor 3D laser radar data; obtaining coordinate values based on a laser radar coordinate system according to the indoor 3D laser radar data; sending the coordinate values to a preset plane equation to obtain a ground plane normal vector; sending the ground plane normal vector to a first preset coordinate system to establish a constraint to obtain a comprehensive error value; and accumulating squares of values in the comprehensive error value to obtain a comprehensive error sum of squares; extracting a minimum value in the comprehensive error sum of squares, and setting a coordinate point corresponding to the minimum value as an optimal current pose. The application is suitable for various lasers, and by giving a preset threshold, whether it is 16 lines, 32 lines or 128 lines, the algorithm accuracy and robustness are ensured, and the accuracy of recognized ground points is improved.
Owner:GUANGZHOU GOSUNCN ROBOTICS CO LTD

Method and device for adjusting angle of target to be measured, equipment and medium

The invention provides a to-be-measured target angle adjusting method and device, equipment and a medium, a to-be-measured target and a starting point of the to-be-measured target are determined from a wafer, and in the to-be-measured target, a to-be-measured point is determined based on the starting point; in the to-be-detected target, three-dimensional coordinates of n data detection points with the to-be-detected point as the center are determined, the n data detection points are used for forming a quadrangle surrounding the to-be-detected point, in the n data detection points, the difference between the distance between each data detection point and the to-be-detected point in the xy plane and a first preset distance meets a first similar condition, and n is equal to 4; a plane equation of a fitting plane is calculated based on the three-dimensional coordinates of the fitting points, the fitting points comprise n data detection points, and the fitting plane is a plane where the area where the to-be-detected point is located is located; and according to the plane equation, determining an angle of the fitting plane relative to a preset reference plane, and adjusting the to-be-measured target based on the angle. According to the invention, high-precision measurement can be realized, and the angle of the to-be-measured target can be accurately adjusted.
Owner:SKYVERSE TECH CO LTD

Image-based three-dimensional modeling method, device, electronic equipment and storage medium

The application provides a kind of based on image three-dimensional modeling method, device, electronic equipment and storage medium, based on image three-dimensional modeling method, comprising: obtaining the multiple target images of the object to be modeled, and the target image is the image of different regions on the object to be modeled;Based on any one target image, determine a known plane and known plane equation;Based on multiple target images and known plane, the target plane equation of predetermined target plane is calculated, when the corresponding target plane equation is known, the corresponding predetermined target plane is known plane, and the corresponding target plane equation is known plane equation;Based on all known planes and all known plane equations, a three-dimensional space model of the object to be modeled is constructed.The application can quickly three-dimensional model the object to be modeled based on image three-dimensional modeling method, device, electronic equipment and storage medium, so as to improve the efficiency of three-dimensional modeling, and greatly reduce the cost required.
Owner:FUJIAN HUICHUAN DIGITAL TECH

Method and device for adjusting angle of target to be measured, equipment and medium

The invention provides a to-be-measured target angle adjusting method and device, equipment and a medium, a to-be-measured target and a starting point of the to-be-measured target are determined from a wafer, and in the to-be-measured target, a to-be-measured point is determined based on the starting point; in the to-be-detected target, three-dimensional coordinates of n data detection points with the to-be-detected point as the center are determined, the n data detection points are used for forming a quasi-circle surrounding the to-be-detected point, in the n data detection points, the difference between the distance between each data detection point and the to-be-detected point in the xy plane and a first preset distance meets a first similar condition, and n is larger than 4; a plane equation of a fitting plane is calculated based on the three-dimensional coordinates of the fitting points, the fitting points comprise n data detection points, and the fitting plane is a plane where the area where the to-be-detected point is located is located; and according to the plane equation, determining an angle of the fitting plane relative to a preset reference plane, and adjusting the to-be-measured target based on the angle. According to the invention, high-precision measurement can be realized, and the angle of the to-be-measured target can be accurately adjusted.
Owner:SKYVERSE TECH CO LTD

Ellipsoid vector map drawing method and system based on cubic polynomial spline

The disclosure provides an ellipsoid vector mapping method and system based on cubic polynomial splines, and relates to the technical field of computer graphics, which takes any point outside the ellipsoid as an observation point, maps the observed ellipsoid into a vector graph on a plane, and comprises the following steps: based on the ellipsoid equation to be mapped and the coordinates of the observation point, the plane equation on which the observed ellipsoid contour is located is calculated; according to the ellipsoid equation and the plane equation, the implicit equation of the projection ellipse is constructed; the projection ellipse is segmented and converted into a cubic spline curve through the implicit equation of the projection ellipse; based on the cubic polynomial spline method, the closed area surrounded by the cubic spline curve is filled to obtain the plane projection of the ellipsoid, and the vector graph on the plane is completed. The disclosure can map a three-dimensional ellipsoid into a two-dimensional vector graph, and the related technology can be applied to the development of three-dimensional drawing software with a derived vector graph function, and plays an important role in the production of high-quality illustrations of books, documents and courseware.
Owner:SHANDONG UNIV

Analysis method for bearing capacity of two-span concrete floor under column end restraint

The application discloses a method for analyzing bearing capacity of two-span concrete floor slabs under column end constraints, comprising: obtaining position parameters of the concrete floor slabs, calculating displacement coefficients of different beams based on the position parameters; establishing slab plane equations of a yield line load stage based on the displacement coefficients, obtaining slab rotation angles of each slab along x and y coordinate axes based on the slab plane equations; calculating yield line load values according to the virtual work principle based on the slab rotation angles; calculating membrane force parameters based on force balance equations, moment balance equations and elliptical regions of each slab; establishing plane equations of each slab under a limit state, calculating bearing capacity increase coefficients according to the plane equations; obtaining a total increase coefficient based on the force equivalence principle, and obtaining a limit bearing capacity based on the total increase coefficient and the yield line load values. The application can make the bearing capacity of the reinforced concrete floor slabs under column end constraints have a smaller error compared with the actual situation.
Owner:CHINA UNIV OF MINING & TECH

A method, device, equipment and storage medium for determining the positional relationship between a point and an irregular hexahedron unit

The present application discloses a method, apparatus, device and storage medium for determining the positional relationship between a point and an irregular hexahedron unit, which relates to the field of aircraft simulation technology, and includes: determining a bounding box based on the minimum and maximum values of each vertex of the irregular hexahedron of the grid model of the aircraft body component in each direction in the three-dimensional coordinates; if the point to be detected in the aircraft simulation space is located inside the bounding box, processing each vertex in the plane by using the centroid corresponding to the plane to obtain a deviation vector; determining a covariance matrix based on the coordinate information of each deviation vector, the centroid and each vertex, and setting the eigenvector corresponding to the smallest eigenvalue among several eigenvalues in the covariance matrix as the normal vector of the plane; determining the signed distance from the point to be detected to each plane by using the target fitting plane equation determined based on the normal vector and the centroid, so as to determine the position information of the point to be detected. In this way, the determination efficiency of the positional relationship between the point and the irregular hexahedron unit can be improved.
Owner:CALCULATION AERODYNAMICS INST CHINA AERODYNAMICS RES & DEV CENT

Transient stability assessment method, system, terminal equipment and storage medium for multi-machine system based on hyper-tangent plane

The present invention discloses a method, system, terminal device and storage medium for transient stability assessment of a multi-machine system based on a hyper-tangent plane. The method constructs a differential algebraic equation group of the multi-machine system according to the state quantity of the multi-machine system, calculates the equilibrium point and Jacobian matrix of the multi-machine system according to the differential algebraic equation group of the multi-machine system, and then determines a class of unstable equilibrium points and Jacobian matrices thereof. The hyper-tangent plane equation is calculated according to the Jacobian matrix of the class of unstable equilibrium points. The nonlinear characteristics of the multi-machine system are analyzed by the hyper-tangent plane equation and the fault trajectory to calculate the critical fault removal time of the multi-machine system, and the transient stability of the multi-machine system is evaluated according to the critical fault removal time, thereby improving the accuracy of the transient stability assessment of the multi-machine system, ensuring the stable operation of the multi-machine system, and solving the problem that the transient stability assessment result of the multi-machine system is low due to the lack of analysis of the nonlinear characteristics of the multi-machine system in the time domain simulation method.
Owner:POWER DISPATCHING CONTROL CENT OF GUANGDONG POWER GRID CO LTD +1

A kind of bed positioning data checking method, system, equipment and storage medium

ActiveCN116011120BGeometric CADSustainable transportationAlgorithmPlane equation
The application discloses a kind of cradle positioning data checking method. Translational coincidence is carried out to cross section cradle layout and ship body frame line drawing, the coordinates of cross section cradle layout in ship body coordinate system are obtained, and the plane equation of cradle base surface is calculated by selecting three characteristic points not collinear on cradle base surface arbitrarily;The projection line of stake line passing through all frame lines on cradle base surface is selected as X axis, the projection point of intersection of stake line passing through all frame lines and middle frame line on cradle base surface is selected as origin, Z axis is determined according to origin and intersection, Y axis is determined according to right-hand rule, and observation coordinate system is established;The transformation matrix of ship body coordinate system and observation coordinate system is calculated;The coordinates of each outer plate piece vertex in observation coordinate system are calculated and taken as checking data to judge the correctness of cradle positioning data. The technical scheme of the application simplifies the design process and design difficulty, quickly and simply judges the correctness of cradle data, and provides accurate basis for subsequent work arrangement and decision-making.
Owner:GUANGZHOU WENCHONG SHIPYARD CO LTD

A gpu-based invisible object culling method and system

This invention discloses a GPU-based method and system for culling invisible objects. The method calculates the six plane equations of the view frustum of the observation camera and the world coordinates of each observed object. It then uses the GPU to calculate in parallel the front or back face of each observed object on a certain plane of the view frustum, thereby determining whether the object is outside the view frustum and culling all objects outside the view frustum. Next, hierarchical Z-buffer data is generated in the GPU using the depth map of the current frame. The object's position and other information are passed to the GPU and used to calculate with the hierarchical Z-buffer data, culling completely occluded objects. This invention utilizes the parallel computing power of the GPU, improving culling efficiency, significantly reducing the CPU computational burden during rendering, and reducing the probability of culling errors.
Owner:ZHEJIANG UNIV

Spectral confocal probe pose calibration method and device based on plane constraint

The application provides a plane constraint-based spectral confocal probe pose calibration method and device, and belongs to the field of precision measurement and instrument technology.The method comprises the following steps: firstly, at least three non-coplanar plane standard parts are measured by using a contact probe, and through coordinate conversion and fitting, equations of the standard planes in a machine coordinate system are accurately established; then, the same plane parts are measured by using a spectral confocal probe, and the obtained measurement point coordinates and distance values are combined with the known plane equations to construct a linear over-determined equation set about the probe pose parameters (including an optical axis direction vector and a space position vector); finally, the equation set is solved by using a least square method to obtain accurate pose parameters.The application converts a nonlinear problem into a linear solution, avoids iterative calculation, and significantly improves the calibration efficiency and accuracy.Meanwhile, the use of plane constraint allows the measurement points to be uniformly distributed, effectively reduces the equation set ill-conditioning, and enhances the robustness of the calibration process.
Owner:HUAZHONG UNIV OF SCI & TECH

Method, device and storage medium for predicting geological structure ahead of tunnel face

The present invention relates to the field of geological engineering and digital modeling technology, and provides a method, device, and storage medium for predicting geological structures in front of a tunnel face. By drawing geological element objects on a registered real-life three-dimensional model, constructing various surface equations of a cavern BIM model, solving the spatial intersection line parameters between the fitted plane equation and the surface equation, and obtaining the spatial Boolean operation results of the surface equation with the cavern BIM model, all geological element objects and spatial intersection line expressions and their corresponding starting point parameters that intersect with the cavern BIM model are obtained. The range of the cavern pile number segment to be blasted in front of the tunnel face is obtained according to the pile number of the tunnel face, and all geological element objects within the cavern pile number segment that intersect with the underground cavern are searched and used as the geological structure element set to be predicted. The present application has the advantages of high efficiency, high precision, and three-dimensional visualization, and realizes the dynamic prediction of geological structures in front of the tunnel face.
Owner:POWERCHINA ZHONGNAN ENG

Method for retrieving repetitive building elements based on axial movement and local matching

The application discloses a repetitive building element retrieval method based on axial movement and local matching, and specifically comprises the following steps: carrying out preliminary segmentation and optimization on a building facade scene; randomly selecting a building element sample under user driving; determining the X axis of the building facade and other two axes by solving a plane equation; transforming the building element sample to the left lower corner origin of the building facade scene by using an OBB bounding box; extracting key points of the element to be retrieved by using an internal shape descriptor; constructing a local matching constraint by combining FPFH and the OBB bounding box; finally, finding the nearest point of the key points of each element to be retrieved, comparing the difference between the descriptors by using the Euclidean distance, and completing the retrieval of the repetitive building element. The application can directly retrieve the repetitive building element in the building facade scene, and solves the problems of the fuzziness of the retrieval object and the low recall rate in the previous retrieval methods.
Owner:XIAN UNIV OF TECH

Point and irregular hexahedron unit position relation judgment method and device, equipment and storage medium

The invention discloses a point and irregular hexahedron unit position relation judgment method, device and equipment and a storage medium, and relates to the technical field of aircraft simulation, and the method comprises the steps: determining a bounding box based on the minimum value and the maximum value of each vertex of an irregular hexahedron of an aircraft body component grid model in each direction in a three-dimensional coordinate; if the to-be-detected point in the aircraft simulation space is located in the bounding box, processing each vertex in the plane by using a mass center corresponding to the plane to obtain a deviation vector; determining a covariance matrix based on the coordinate information of each deviation vector, the centroid and each vertex, and setting a feature vector corresponding to the feature value with the minimum numerical value in a plurality of feature values in the covariance matrix as a normal vector of a plane; and determining a signed distance from the to-be-detected point to each plane by using a target fitting plane equation determined based on the normal vector and the centroid so as to judge the position information of the to-be-detected point. Therefore, the judgment efficiency of the position relation between the point and the irregular hexahedron unit can be improved.
Owner:CALCULATION AERODYNAMICS INST CHINA AERODYNAMICS RES & DEV CENT

A container positioning method, system, device and storage medium based on laser radar

The application provides a container positioning method, system, device and storage medium based on a laser radar, the method comprising: acquiring first point cloud data covering a container and a loading and unloading platform, iteratively fitting the first point cloud data through a RANSAC algorithm, obtaining plane equations corresponding to a plurality of dominant planes of the segmented container, calculating a current pose of the container in a reference coordinate system according to the plane equations of the plurality of dominant planes, and determining first pose parameters; in the process of moving the container or the loading and unloading platform, acquiring second point cloud data obtained by scanning the environment at the tail of the container, performing local feature extraction and cluster filtering on the second point cloud data through an eight-neighborhood image algorithm to determine the position of the tail of the container, correcting the first pose parameters according to the position of the tail of the container, and outputting second pose parameters of the container. The application cooperates with a plurality of laser radars, ensures the real-time performance and point cloud integrity of scanning detection, and improves the accuracy and efficiency of container pose measurement.
Owner:GUANGZHOU DUGE TECH CO LTD

Terrain database carving around the runway

The vertical resolution and / or vertical accuracy of terrain elevation data in the vicinity of an aircraft runway is adjusted by obtaining local terrain data to generate a first elevation value for a query location. A processor, upon receiving the first elevation value, calculates a plane equation based on a predetermined standard model suitable for geometrically conforming to the aircraft runway to generate a second elevation value for the query location. The processor selectively uses the first and second elevation values ​​to generate an adjusted elevation value provided to a terrain avoidance and warning system.
Owner:GULFSTREAM AEROSPACE CORP

A high-precision edge three-dimensional reconstruction method for groove cutting

This invention discloses a high-precision 3D edge reconstruction method for bevel cutting. The method first acquires the original point cloud and grayscale image of the workpiece using a binocular vision system; then, it uses the filtered clean point cloud to fit the plane equation of the workpiece surface as a geometric constraint; next, it performs adaptive feature enhancement on the grayscale image to extract high-precision sub-pixel 2D edges; finally, it combines the plane equation and the 2D edges, calculates the 3D coordinates of the edges using a ray intersection model, and generates the robot cutting trajectory. This invention effectively solves the problems of point cloud loss and distortion caused by edge burrs, defects, and reflections, achieving sub-millimeter-level edge reconstruction and significantly improving the consistency of bevel cutting edges and trajectory accuracy without manual intervention.
Owner:NANTONG MINYUE TECHNOLOGY CO LTD

A method for measuring lattice constants of a close-packed hexagonal system based on spatial plane fitting

The application discloses a method for measuring close-packed hexagonal lattice constant based on space plane fitting, which comprises the following steps: firstly, obtaining the X-ray diffraction spectrum of a close-packed hexagonal crystal and indexing; secondly, converting the crystal plane spacing formula into a three-dimensional space plane equation through mathematical transformation; thirdly, calculating a plurality of groups of data according to the measured diffraction angle and performing space plane fitting to obtain a space plane equation containing an intercept; fourthly, introducing a goniometer zero drift error correction quantity to perform multiple iteration correction on the measured angle until the absolute value of the intercept of the fitting plane tends to be zero, so that the accurate value is obtained; and finally, calculating the high-precision lattice constant. The application converts the complex parameter fitting problem into an intuitive space plane fitting and intercept correction process, has clear principle and strong operability, and effectively improves the measurement precision of the close-packed hexagonal lattice constant.
Owner:NORTHWEST INSTITUTE FOR NONFERROUS METAL RESEARCH

Revolving body size measurement method and system based on geometric constraint vision measurement system

The invention discloses a rotary body size measurement method and system based on a geometric constraint vision measurement system, a storage medium and electronic equipment. The method comprises the following steps: constructing and solving a space plane equation based on object space coordinates of a plurality of known feature points on a revolving body; constructing a sphere equation, solving by combining the sphere equation and the space plane equation to obtain an expression of a space circle, and solving a perpendicular bisector expression based on the expression of the space circle; a circle center-perpendicular foot distance calculation model is constructed based on the midperpendicular expression, and circle center coordinates of the rotary body are obtained after calculation; the method comprises the following steps: constructing a lens optical distortion model, constructing a midperpendicular weight coefficient and a weighted circle center-foot distance calculation model based on the optical distortion model, solving the minimum value of the midperpendicular weight coefficient, and substituting the minimum value of the midperpendicular weight coefficient into the weighted circle center-foot distance calculation model to obtain the radius of the rotary body. The calibration error of the rotary body can be improved, the calibration precision is improved, and the measurement efficiency of the rotary body is improved.
Owner:HUBEI UNIV OF TECH

Ellipsoidal vector diagram drawing method and system based on cubic polynomial spline

The invention provides an ellipsoid vector diagram drawing method and system based on cubic polynomial splines, and relates to the technical field of computer graphics, any point outside an ellipsoid is used as an observation point, and the observed ellipsoid is drawn into a vector diagram on a plane. Calculating a plane equation where the observed ellipsoid contour is located; constructing an implicit equation of a projection ellipse according to an ellipsoid equation and the plane equation; segmenting and converting the projection ellipse into cubic spline curves through an implicit equation of the projection ellipse; and based on a cubic polynomial spline method, filling a closed region enclosed by cubic spline curves to obtain a planar projection of the ellipsoid, and completing drawing of the vector diagram on the plane. According to the method, the three-dimensional ellipsoid can be drawn into the two-dimensional vector diagram, the related technology can be applied to development of three-dimensional drawing software with a vector diagram exporting function, and the method plays an important role in manufacturing of high-quality illustrations of books, documents and courseware.
Owner:SHANDONG UNIV

Rapid registration method and registration positioning device for aircraft assembly

PendingCN121169976AImage analysisComputer graphics (images)Object registration
The invention discloses a rapid registration method and a registration positioning device for aircraft assembly, and the method comprises the steps: building a three-dimensional stl model of an aircraft part, and taking a crossed rib on a frame beam of the aircraft part as a virtual-real matching feature point; a plane equation R11 and a plane equation RR2 of the two ribs are obtained respectively, and then a middle plane equation RMid1 and a middle plane equation RMid2 of the two ribs are obtained; and combining the plane equations RMid1 and RMid2 with the top plane equation RTop, and calculating to obtain a plane intersection point as a theoretical registration coordinate point F (x, y, z). And finally, according to the thickness of the real object registration point device, adjusting the offset to obtain an aircraft assembly registration point Final (x + s * a, y + s * b and z + s * c) so as to carry out registration assembly. The method solves the problems that in the prior art, the theoretical coordinates of the registration points cannot be rapidly obtained, the real object registration points are not accurate enough to place, and the adaptability is not high, and has good practicability.
Owner:CHENGDU AIRCRAFT INDUSTRY GROUP

Method, apparatus and storage medium for generating horizontal well connected well profile

The present disclosure provides a method, an apparatus, and a storage medium for generating a horizontal well connected well profile, belonging to the technical field of exploration and development. The generation method includes: obtaining the coordinates of the control points of two horizontal wells, where the control points are the endpoints of equal segments, and the equal segments are multiple continuously connected well segments with equal lengths in the horizontal well; forming a triangular mesh model based on the coordinates of the control points on the two horizontal wells, where the triangular mesh model is a plane equation formed according to three of the control points; performing texture mapping on the triangular mesh model according to seismic data to generate the connected well profile. The present disclosure can generate a connected well profile reflecting the well trajectory of a horizontal well, facilitating the intuitive observation of various data information of the formation.
Owner:CHINA NAT PETROLEUM CORP +1

Planar rectangular heliostat shadow efficiency calculation method based on geometric relationship simplification

The invention discloses a plane rectangular heliostat field shadow efficiency algorithm, which improves a common heliostat shadow efficiency calculation method based on a geometrical relationship, and has the advantages of simplicity in calculation, high accuracy and convenience in understanding. The calculation thought is as follows: screening neighbor heliostats: only considering potential shielding mirrors within a distance threshold (reducing the calculation amount); constructing a key vector: calculating a sun incidence vector and a heliostat normal vector (determining a mirror surface and a light ray direction) through a sun angle and a heat collector position; discretizing the mirror surface: splitting the surface of the judged heliostat into fine grid points (numerical area calculation); light intersection detection: for each grid point, emitting light along the reverse direction of the sun, and judging whether the light intersects with a neighbor mirror (determining a shadow point); calculating efficiency: counting the proportion of shadow grid points, and obtaining the shadow efficiency by using '1-shadow area / total area'. Wherein key vector construction and light intersection detection algorithms are all based on a global coordinate system, a plane equation and a linear equation are constructed by using a geometrical relationship for simultaneous solution, the processes of coordinate transformation and complex equation solution are omitted, the calculation amount and the calculation difficulty are greatly reduced, and meanwhile, good precision is still kept.
Owner:张恒

Shield tunneling unit target thrust calculation method and system based on plane equation

The application relates to a shield propulsion unit target thrust calculation method and system based on a plane equation, which comprises the following steps: establishing a space rectangular coordinate system O-XYZ on the installation surface of a shield propulsion system of a shield tunneling machine; determining the angle of a target total thrust point P in a plane XOY; selecting a characteristic propulsion unit in the first quadrant or the second quadrant of the plane XOY; establishing a local coordinate system xOy; setting a target thrust z for each propulsion unit i :z i i =(i=1~n); setting the target thrust of the propulsion unit in a thrust plane, obtaining the values of z0 and k based on the plane equation of the thrust plane, and then obtaining the target thrust of each propulsion unit according to z i =(i=1~n); setting the target thrust of the propulsion unit in a thrust plane, obtaining the values of z0 and k based on the plane equation of the thrust plane, and then obtaining the target thrust of each propulsion unit according to z i The application makes the target thrust of each propulsion unit of the propulsion system meet the condition of being in the same plane, minimizes the difference of the target thrust of each propulsion unit, and solves the problem that the single segment is significantly different in ring surface stress during shield propulsion, thereby ensuring the safety of the segment structure.​
Owner:SHANGHAI TUNNEL ENG CO LTD +1