94 results about "Planar projection" patented technology

The invention discloses a welding seam track identification method for impeller wrap angle welding based on point cloud data, and belongs to the field of machine welding seam identification, and the method comprises the following steps: carrying out filtering, down-sampling and clustering on original scanning point cloud; classifying the point cloud data through a region growing clustering algorithm; determining an optimal interception plane based on principal component analysis, and performing curve fitting on section data to obtain a preliminary main welding seam track; the main welding seam track is projected to a local approximate plane in a segmented mode, and accurate extraction of the main welding seam track is completed; and performing plane fitting and thickness calculation on the wrap angle surface, solving an intersection line in combination with an adjacent local approximate plane, calculating an intersection point of the intersection line and the main welding seam track, and finally generating a wrap angle welding seam track in combination with the direction of the intersection line and the wrap angle thickness. Through cooperative calculation of local plane projection and spatial intersection line solving, the whole process operation from recognition, planning to welding can be automatically completed, and unmanned intelligent welding in the true sense is achieved.

A large-scale point cloud-oriented two-dimensional regularized planar projection method and an encoding and decoding method are disclosed. The two-dimensional regularized planar projection method includes: obtaining original point cloud data; initializing a two-dimensional projection plane structure of a point cloud; and determining a mapping relationship between the original point cloud data and the two-dimensional projection plane structure to obtain a two-dimensional regularized projection plane structure corresponding to the point cloud. The encoding and decoding method includes: predicting based on the two-dimensional regularized projection plane structure of the point cloud to obtain to-be-encoded data; dividing the to-be-encoded data into a first type of to-be-encoded data and a second type of to-be-encoded data; and encoding different data in the first type of to-be-encoded data separately in a preset encoding manner, and correspondingly encoding the second type of to-be-encoded data, to obtain a geometric information bitstream.

The invention discloses a non-line-of-sight positioning method based on obstacle vectorization and distance measurement cross validation, which belongs to the technical field of wireless positioning and comprises the following steps: step 1, calculating a height difference according to the installation height of a base station and the preset height of a to-be-estimated label, and calculating a plane projection distance value according to the height difference and a TOF distance measurement value; 2, constructing a signal path according to a to-be-estimated label positioning result at the previous moment and the position of each base station, judging the penetration condition of the path by combining a vectorized obstacle map, and performing compensation and reliability screening on the plane projection distance based on the penetration condition to obtain a credible distance measurement value set; 3, solving and calculating a positioning residual error through multi-base-station combined positioning, and carrying out weighted fusion on a solving result according to the residual error to obtain an initial positioning result at the current moment; according to the invention, high-precision positioning can still be kept near the base station and in complex scenes such as multi-shielding and the like, and the application requirement of a shielding environment is met.

A computer-implemented method and system relate to an image encoder that receives a digital image as input. The image encoder generates a weight map using the prior feature map. A prior feature map is generated using pixels of the digital image. A weight map is generated based on Lie data associated with the digital image. The homography is interpolated between the two planar projections of the digital image using at least the weight map and the homography matrix. The homography matrix provides a mapping between two planar projections of the digital image. A homography kernel is generated by applying homography to the convolution kernel. A homographic transform kernel is applied to the prior feature map to convolve different planar regions appearing in the digital image, and a new feature map is generated for computer vision tasks involving three-dimensional (3D) perception.

This invention discloses a chemical plating batch clamping fixture based on structural constraint and its application method, belonging to the field of fixture technology. The fixture includes at least one clamping unit, comprising an upper frame, a lower frame, and isolation columns connecting the upper and lower frames. After assembly via the isolation columns, the upper and lower frames have corresponding hollow structures. The contour of the hollow structures matches the planar projection contour of the workpiece. A sandwich structure exists between the upper and lower frames. Longitudinal and transverse protrusions are provided around the hollow structures to constrain the parts within the hollow structure area. Based on the principle of physical interference, the fixture is highly effective in preventing the flipping of lightweight, small parts, eliminating damage to the parts, and is particularly suitable for precision parts.

The invention discloses a CT image-oriented implant space attitude estimation method, and belongs to the technical field of biomedical engineering and computer science. The method comprises the following steps: extracting a target three-dimensional model based on a CBCT image; the CBCT image is obtained by performing cone beam scanning on a target part where an implant is placed during or after an operation; obtaining an implant theoretical model pre-constructed for the implant; the mass center of the target three-dimensional model and the mass center of the implant theoretical model are calculated respectively, and the mass center of the target three-dimensional model and the mass center of the implant theoretical model are aligned; registering the target three-dimensional model and the implant theoretical model of which the mass centers are aligned by utilizing a main shaft rotating mode; and evaluating the registration precision based on multi-plane projection and similarity measurement, and outputting spatial attitude parameters of the implant. According to the method, the registration speed can be increased, the calculation complexity in the registration process is reduced, and the space registration precision can be further improved through a two-stage optimization strategy of centroid alignment and main shaft rotation.

The invention discloses an adaptive shadow generation method based on planar projection guidance and depth perception diffusion, and belongs to the technical field of computer vision and image synthesis. The method comprises the following steps: in a first stage, generating a hard shadow mask of a foreground object under a virtual light source through physical projection calculation, and providing geometric position and shape priori; in the second stage, multi-modal conditions such as a hard shadow mask, a background depth image and a foreground and background fusion image and noise latent variables are uniformly coded into a Token sequence, the Token sequence is input into a Diffusion Transform model, detail rendering is carried out through a self-attention mechanism, and a composite image with a realistic shadow is output. According to the method, the problems of shadow geometric distortion, inconsistent illumination, insufficient texture fitting and the like in the prior art are solved through a mixed frame combining physical guidance and neural rendering.

The invention relates to the technical field of air traffic management, in particular to an analog simulation method and system for a low-altitude traffic digital twin platform, and the method comprises the steps: obtaining a road plane projection drawing of a target area from the digital twin platform, the road plane projection drawing comprises buildings, roads and backgrounds, and dividing each road into a plurality of road sections; determining a risk cardinal number of the road section; determining the risk weight of the aircraft reaching each road section based on the intersection point between the road sections, the length of each road section and the real-time wind speed of the target area; and determining the comprehensive weight of each road section by using the risk weight, the risk cardinal number and the distance weight of each road section, and determining the final shortest path of the aircraft from the starting point to the terminal point in the target area according to the comprehensive weight. Therefore, the reliability and the safety of the shortest path planning of the aircraft are improved.

The invention relates to the technical field of surveying and mapping engineering, in particular to a lead precision estimation system which comprises a data acquisition module, a coordinate conversion module, a lead design module, a precision estimation module, a visual display module, a data interaction module and a data storage module. The data acquisition module collects geographic space data of a to-be-processed area and parameters of a measuring instrument; the coordinate conversion module converts the latitude and longitude coordinates into plane projection coordinates through Gaussian positive calculation; the wire design module constructs an edge measurement net, an angle measurement net or a corner net, sets an edge length threshold value, and matches instrument parameters corresponding to a second-level control net and a fourth-level control net; the precision estimation module calculates a weakest point median error and a weakest edge relative median error, and decomposes and calculates a plane through error; the visualization module draws a lead element and an error ellipse on the online map; data interaction supports CSV format import and export, and the storage module stores data support operation through a unified array. The method improves the estimation efficiency and precision, adapts to multiple engineering scenes, and reduces the achievement application threshold.

This invention discloses a method and apparatus for extracting three-dimensional deformation data of mining subsidence in desert areas, relating to the field of Earth observation technology. The invention calculates the angle between the normal vectors of each point in the point cloud data and performs tangent plane projection analysis to form multiple pairs of point cloud contour sets. The overall approach is based on the local geometric characteristics of the point cloud, accurately extracting feature points reflecting the shape of the point cloud contours. Then, using these multiple pairs of point cloud contour sets as registration objects, the K-4PCS and VGICP registration algorithms are employed to register the three phases of point cloud data, ensuring precise alignment and obtaining the registered point cloud and transformation matrix. The three-dimensional deformation of the land surface is extracted from the transformation parameters in the transformation matrix. This process eliminates the need for subsidence extraction based on point DEMs and planar displacement extraction based on rigid body matching, enabling accurate extraction of planar displacement in desert areas and precise acquisition of three-dimensional deformation data of the land surface caused by mining in desert regions.

The invention provides a hydraulic structure surface crack detection method based on plane projection, and belongs to the technical field of image processing and deep learning, and the method comprises the following steps: collecting an original image of a hydraulic structure surface, and carrying out the preprocessing of the original image; performing three-dimensional modeling and model cutting based on the preprocessed image; the method comprises the following steps: acquiring hydraulic structure point cloud data based on three-dimensional modeling, and then performing plane projection on a detected surface again according to a normal vector of the detected surface to form a re-projection image; performing image cutting and image marking on the collected original image, and training an intelligent crack detection model; and performing crack detection on the cut re-projection image by using the intelligent crack detection model, and splicing the detected images. According to the method, intelligent detection of the large-size slope hydraulic structure is realized, and the precise detection effect of the slender crack on the surface of the hydraulic structure is realized through combination of small-size image cutting, labeling and YOLO series models.

The application discloses a GPS static drift detection method and system based on trajectory morphology analysis, and belongs to the field of satellite navigation data processing; the method comprises the following steps: acquiring an original GPS trajectory point sequence, and performing plane projection conversion on coordinates to obtain plane coordinate trajectory data; a fixed length sliding window is used to extract local trajectory morphology features, and the confidence of the window to normal driving and static drift is respectively evaluated, normalized state probability is output, and preliminary judgment is performed according to a preset decision threshold to obtain a window level state label; based on the window level state label, context-driven iterative timing smoothing and decision mechanism are used to eliminate state jitter and determine a final window state label; the final window state label is mapped back to the original GPS trajectory point, and is aggregated into an initial trajectory segment to obtain a driving segment or a drift segment with a preliminary state label; and heuristic review and correction are performed on the initial trajectory segment to output a final state labeling result.

The invention discloses a mid-infrared detection array plane based on gate modulation photoelectric gain, the mid-infrared detection array plane is constructed on a flexible insulating substrate, the mid-infrared detection array plane comprises a plurality of pixel units arranged in a periodic array, and each pixel unit comprises a gate, an insulating layer, a source, an active layer and a drain in sequence from bottom to top; the active layer comprises a lead selenide thin film, a two-dimensional molybdenum disulfide layer and a black phosphorus quantum dot layer which sequentially cover the source electrode; and the source electrodes and the drain electrodes are interdigital and are symmetrically distributed in a staggered manner on a plane projection. According to the mid-infrared detection array plane, flexible switching between a quick response mode and a high-gain mode can be achieved, the detection requirements of high-frequency transient signals and low-frequency slowly-changing signals are considered, meanwhile, the detection sensitivity of mid-infrared signals is improved, noise and dark current are reduced, and the working power consumption of devices is reduced.

The invention discloses an urban building reconstruction method and device, electronic equipment and a storage medium, which are used for solving the technical problems of high data acquisition cost, high operation cost, limited application range and low efficiency during urban building reconstruction in the prior art. The method comprises the following steps: acquiring an urban aerial image, and extracting an outer contour feature map and an inner ridge line feature map containing all buildings in the image from the urban aerial image; performing feature line vectorization based on node simplification and direction rule optimization according to the outer contour feature graph and the inner ridge line feature graph to obtain a plurality of outer contour line segments and a plurality of inner ridge line segments; according to the plurality of outer contour line segments and the plurality of inner ridge line segments, performing inner and outer contour line combination based on a single building, and obtaining a two-dimensional region segmentation map of each building; and for each building, generating a three-dimensional building model corresponding to the two-dimensional region segmentation map in combination with the digital surface model and the planar projection.

This invention discloses a mid-infrared detection array based on gate modulation photoelectric gain. The mid-infrared detection array is constructed on a flexible insulating substrate and includes a plurality of pixel units arranged in a periodic array. From bottom to top, each pixel unit includes: a gate, an insulating layer, a source, an active layer, and a drain. The active layer includes a lead selenide thin film, a two-dimensional molybdenum disulfide layer, and a black phosphorus quantum dot layer sequentially covering the source. Both the source and drain are interdigitated and symmetrically staggered in planar projection. The mid-infrared detection array of this invention can achieve flexible switching between fast response and high gain modes to meet the detection requirements of both high-frequency transient and low-frequency slowly varying signals, while improving the detection sensitivity of mid-infrared signals, reducing noise and dark current, and reducing the power consumption of the device.

Method for aligning two oppositely arranged optical subsystems (12u,12u',12u'',12o,12o',12o'') of an optical system (11,11',11"), comprising the following steps: - Projection of alignment marks (9l, 9r, 9l', 9r') into an image plane (5u) of the first optical subsystem (12u, 12u', 12u''), - Projection of the alignment marks (9l,9r,9l',9r') from the first image plane (5u) onto a sensitive surface (14so) of the second optical subsystem (12o, 12o', 12o''), - Alignment of the optical subsystems (12u,12u',12u'',12o,12o',12o'') to each other, such that projections (9pl,9pr) of the alignment marks (9l,9r,9l',9r') are imaged at ideal positions (9il,9ir) in a depth of field area of ​​the sensitive surface (14so), characterized in that the alignment marks (9l, 9r) are applied directly to a first sensitive surface (14su) of a first camera chip (2u), wherein the alignment marks (9l, 9r) have a collection of non-functional pixels.

A computer-implemented method and system refer to an image encoder that receives a digital image as input. The image encoder generates a weighting map using a preceding feature map. The preceding feature map is generated using pixels of the digital image. The weighting map is generated based on Lie data associated with the digital image. A homographic transformation is interpolated between two planar projections of the digital image using at least the weighting map and a homography matrix. The homography matrix provides a mapping between the two planar projections of the digital image. Homographically transformed kernels are generated by applying the homographic transformation to convolution kernels.The homographically transformed kernels are applied to the preceding feature map to perform folding on different planar areas appearing in the digital image and to generate a new feature map that is used for a computer vision task involving three-dimensional (3D) perception.

The application provides a passive operating arm RCM geometric projection positioning method, determines the number N of connecting rods of the passive operating arm, when N=2, the first connecting rod may deviate compared with the initial state of the first connecting rod, and the second connecting rod only performs a translation movement; according to whether the first connecting rod deviates compared with the initial state of the first connecting rod, the plane projection position of the fixed point is solved respectively; when N=3, the first connecting rod and the third connecting rod may deviate compared with the initial state of the first connecting rod and the third connecting rod, the second connecting rod and a virtual connecting rod only perform a translation movement, and the virtual connecting rod refers to a connecting line between the third connecting rod and the fixed point; according to whether the first connecting rod and the third connecting rod deviate compared with the initial state of the first connecting rod and the third connecting rod, the plane projection position of the fixed point is solved respectively; when N>3, the N connecting rods are divided into a plurality of {N=2} base modules and a plurality of {N=3} base modules, and the plane projection position of the fixed point in a combined state is solved. The above method can solve the problem that a doctor is difficult to register and position a medical instrument and a patient workbench.

A kind of tunnel laser point cloud generates lining inner surface image method, comprising: obtaining point cloud data;Splicing forms complete tunnel point cloud;Obtain segmented point cloud;Manual denoising;Load segmented point cloud data, and carry out the downsampling of point cloud data;Point cloud data is projected on plane;Automatic denoising;Extract the contour boundary of two-dimensional plane tunnel point cloud;Determine side wall line point set and caliber line point set;Two side wall line point sets determined are respectively moved mean value smoothing operation;The average width between two side wall lines is calculated;Obtain the central axis point set of tunnel;Obtain central axis;With central axis as reference, carry out two-dimensional image development.The present application can quickly process large-scale tunnel point cloud, generate fine tunnel lining inner surface image, be suitable for medium-length tunnel, super-long tunnel and curved tunnel, provide new method for tunnel lining inner surface image generation, so that tunnel lining apparent disease detection and evaluation are more efficient, convenient, accurate.

This utility model relates to an agile ladder that is easy to fold and store, comprising several connected rectangular frames, each rectangular frame including four flexible ladder ropes, the four flexible ladder ropes being connected end to end to form the four sides of the rectangular frame; each flexible ladder rope is provided with two sets of magnetic attraction components, the magnetic attraction components including long strip-shaped magnetic strips and carbon steel strips, the magnetic strips and carbon steel strips being arranged side by side and attached to each other within the flexible ladder rope, the two sets of magnetic attraction components being spaced apart along the length direction of the flexible ladder rope; the sides of two adjacent rectangular frames are connected by a flexible connecting strip; in the magnetic attraction components, the carbon steel strips serve as both support members and, when the ladder ropes are folded, engage and align with the magnetic strips in other parts, facilitating neat folding, easy flat storage, and preventing the ladder from easily falling apart; when folding the agile ladder, a rectangular frame itself can be folded twice, that is, the minimum planar projection of the agile ladder after folding is one-quarter of the area of ​​a rectangular frame.

The invention relates to a rapid inversion method and device for the real area of mass-texted landslides based on DEM gradient constraint. The method comprises the following steps: acquiring group-sending landslide two-dimensional space vector data and DEM data; based on the DEM data, determining regional gradient information; determining plane projection area information based on the group-sent landslide two-dimensional space vector data; determining a landslide center set based on the group-sent landslide two-dimensional space vector data; determining a slope value set based on the landslide center set and the regional slope information; constructing an inversion model from the two-dimensional projection area to the real slope area based on the plane projection area information and the slope value set; and based on an inversion model from the two-dimensional projection area to the real slope surface area, carrying out rapid inversion processing on the plane projection area information so as to generate group-sending landslide real area information. According to the invention, authenticity and precision of real landslide area estimation can be improved.

The application provides a double-curvature fusion curved surface SLAM navigation method, a longitudinal and transverse double-direction curvature parameter is estimated in real time through double-IMU fusion, an extended information filtering framework containing a double-curvature kinematic model, a laser data curved surface projection compensation algorithm and a path double-curvature compensation algorithm are constructed, and the scheme can accurately depict the curved surface geometric constraint where the robot actually locates; the accumulation of the transverse positioning error is inhibited through online estimation and fusion of the transverse curvature parameter; the accurate description and compensation of the robot side slip effect are realized through the establishment of a kinematic model containing a double-curvature coupling term; the data distortion is eliminated and the environment perception accuracy is improved through the projection of the laser scanning data from a plane to the estimated curved surface; finally, the consistency of the control instruction and the curved surface geometry is ensured through the real-time geometric compensation of the planning path based on the double-curvature parameter, and the stability and trajectory tracking accuracy of the control system under the longitudinal and transverse curvature coupling effect are enhanced.

The present application belongs to the technical field of underground metal mine blasting engineering, and relates to a kind of blast pile point cloud under segmentation extraction method.The method comprises: obtaining blast pile original three-dimensional point cloud data;The blast pile original three-dimensional point cloud data is preprocessed, and the blast pile three-dimensional point cloud model is reconstructed;Based on KD tree, the neighborhood search structure is constructed and the resolution is determined;The blast pile three-dimensional point cloud model is segmented to generate segmented result point cloud;Through principal component analysis, an oriented bounding box (OBB) is constructed, its orthogonal direction vector and edge length are obtained;The OBB direction vector and the plane are used as the projection direction and the plane, and three orthogonal projection point clouds are obtained;According to the projection point cloud parameter, the neighborhood radius is set, and the local density is calculated;The maximum value of the density is counted, and the point cloud greater than the threshold value is determined as the under-segmentation point cloud, which needs to be re-segmented.The beneficial effects are: through the local density analysis of the plane projection point cloud, the under-segmentation point cloud is accurately identified, which provides a basis for adjusting the segmentation strategy and improves the segmentation accuracy and precision.

Disclosed are an imaging apparatus and method, and a device. The imaging apparatus includes an imaging element with an imaging surface of a spherical structure, where angles between all parts of the spherical imaging surface and light emitted by an image source at an intersection of the imaging surface are 90°, and plurality of imaging units are regularly arranged on the imaging surface. The imaging element is used to completely, intactly and accurately obtain a scene image, and the obtained image is displayed by using the display device whose display surface has the same structure as and is corresponding to a reverse spherical display surface, such that a highly vivid three-dimensional picture completely consistent with a scene is presented, thereby overcoming the defect that the highly vivid three-dimensional scene picture is difficult to obtain and present by a flat projection surface based imaging method.

The invention discloses a high-precision mapping method and system for a converter station oil sample collection robot. The method comprises the steps that firstly, point cloud data are collected through a laser radar, aggregation key points are extracted, and descriptors based on horizontal plane projection and sector distance features are generated; the core lies in that a three-dimensional feature hash mapping closed-loop retrieval algorithm is adopted, and efficient loopback detection is carried out by calculating the ratio factor of the frequency of descriptor keys and the inverse document frequency. And when a loop is detected, constructing a closed-loop factor, fusing the closed-loop factor into a global factor graph model, and optimizing a global pose by combining a sliding window strategy and a key frame selection mechanism, so as to finally generate a high-consistency global point cloud map. According to the method, accumulative errors in long-distance operation are effectively eliminated, and the mapping precision and navigation reliability of the robot under the complex environment of the converter station are remarkably improved.

The invention belongs to the technical field of underground metal mine blasting mining engineering, and relates to a muck pile point cloud under-segmentation extraction method. The method comprises the following steps: acquiring original three-dimensional point cloud data of a muck pile; preprocessing the original three-dimensional point cloud data of the muck pile, and reconstructing a three-dimensional point cloud model of the muck pile; constructing a neighborhood search structure based on the KD tree and determining the resolution; segmenting the muck pile three-dimensional point cloud model to generate segmentation result point cloud; constructing an oriented bounding box (OBB) through principal component analysis, and obtaining an orthogonal direction vector and a side length of the OBB; taking the OBB direction vector and the plane as a projection direction and a plane to obtain three orthogonal projection point clouds; a neighborhood radius is set according to projection point cloud parameters, and local density is calculated; and counting the maximum density value, judging the point cloud greater than the threshold value as an under-segmentation point cloud, and carrying out re-segmentation. The method has the beneficial effects that the under-segmentation point cloud is accurately identified through plane projection point cloud local density analysis, a basis is provided for adjusting a segmentation strategy, and the segmentation accuracy and precision are improved.

The present application belongs to the technical field of 3D printing model preprocessing, and particularly relates to an edge different-distance support generation method and device, electronic equipment and a storage medium. The method comprises the following steps: traversing a model; obtaining a model frame; aligning the model frame to an origin; lifting the model; dividing a preset grid; selecting a model bottom plane and obtaining a plane projection range; obtaining a preset grid in the projection range; obtaining a boundary grid center point; projecting a straight line upward from the boundary grid center point to form a second set of points by intersecting with the model bottom surface; determining N vertical reference surfaces through the second set of points, and setting the second set of points on the reference surfaces and located at the lowest points as first type points; screening the remaining points to determine second type points; extracting the first type points and the second type points with a distance of L1+△X and L2+△X respectively as extraction points; generating a support unit downward from the extraction points on the boundary intersection points of the model bottom surface; and storing data. The present method can generate different-distance support units in batches at the edges of the model bottom.

The application provides a reference map preparation method containing angle distance information for image matching. The method can improve the range defect of the traditional perspective gnomonic projection algorithm which cannot project the global discrete points on a sphere at equal angle distance, project the global discrete points on a sphere to obtain a reference map for image matching, and extract angle distance features for subsequent image matching from the reference map. The application firstly defines the angle distance information of the discrete points on a sphere, introduces the concept of angle distance scaling on the basis of the perspective gnomonic projection algorithm, scales the angle distance between the plane projection points at a fixed ratio, derives the calculation formula of the improved perspective gnomonic projection algorithm combined with angle distance scaling, and prepares the reference map with high-precision angle distance information. The angle distance information in the reference map is extracted by the cosine law of a spherical triangle and used as feature information for subsequent image matching.

A three-dimensional printing apparatus is configured to manufacture a 3D article in a layer-by-layer manner. The 3D printing apparatus includes a projection device configured to selectively illuminate a photosensitive device along a horizontal build plane defining the horizontal build plane along an X-axis and a Y-axis. The projection device is coupled to a lateral movement mechanism configured to cause the projection device to scan laterally along the X'axial movement coordinates and the Y 'axial movement coordinates. The X'axial movement coordinates and the Y 'axial movement coordinates are not precisely aligned with the X axis and the Y axis, respectively. For each layer of the 3D article, the projection device is configured to illuminate a series of adjacent pixelated tiles within a build plane. Prior to illuminating the series of tiles, the projection device is configured to operate the camera and align a leading edge (46, 46-1) and a trailing edge (48, 48-2) of the tile along each of X 'and Y'.