220 results about "Spherical coordinate system" patented technology

The invention discloses an interactive large-screen visualization system and method based on multi-dimensional data real-time rendering, relates to the technical field of image rendering, and aims to solve the bottleneck problems of a traditional system in the aspects of data throughput efficiency, rendering delay and interactive response. The method comprises the following steps: dividing space blocks by adopting a non-uniform octree, dynamically adjusting the size of the blocks according to data density, and combining a ZSTD + Hoffman hybrid compression algorithm; a CPU-GPU three-level asynchronous processing assembly line is constructed, and task priorities are dynamically adjusted through a fixation point weight algorithm; the master node dynamically allocates LOD parameters, and the slave nodes achieve special-shaped large-screen sub-pixel-level splicing based on a spherical coordinate system model; a Q-learning algorithm is adopted to predict a user operation sequence, and dual-channel bandwidth adaptive allocation is realized in combination with an ASTP protocol. The system comprises a dynamic partitioning module, a pipeline scheduling module, a multi-node cooperation module, an intelligent preloading module and an exception handling module. Real-time interaction visualization of a large amount of data can be realized, the rendering efficiency is improved, and hardware resource occupation is reduced.

The invention discloses a dual-radar three-dimensional wind field inversion method considering standard atmospheric influence under an earth coordinate system, which comprises the following steps of: firstly, converting polar coordinates of radial observation of radars into latitude and longitude grid coordinates, and then converting an inversion grid target point from the latitude and longitude grid coordinates to the earth coordinate system; obtaining position coordinates of the inversion grid target point and the two radars in an earth coordinate system; and finally, performing double-radar wind field inversion considering the standard atmospheric influence under the earth coordinate system, considering the influence of the standard atmospheric influence on the inversion grid target point three-dimensional wind field on the radial speed projection in the inversion wind field iteration equation set, and meanwhile, considering the influence of the density change on the mass continuity equation under the standard atmospheric influence condition. Therefore, accurate calculation of double-radar three-dimensional wind field inversion is realized, and accurate and reliable three-dimensional wind field inversion information is obtained. Based on the method of the invention, accurate calculation of dual-radar three-dimensional wind field inversion can be realized, and accurate and reliable wind field information values can be obtained.

The invention discloses a Delaunay triangle and curvature minimization-based point cloud integrity improvement method and system, and the method comprises the following steps: converting a point cloud under a three-dimensional rectangular coordinate system into a spherical coordinate system, and then projecting the point cloud to a two-dimensional plane coordinate system to form a two-dimensional plane point cloud; carrying out Delaunay triangularization, and then projecting back to a three-dimensional rectangular coordinate system to form a spatial two-dimensional triangular mesh; the side length, the area and the unit normal vector of each triangular mesh are calculated, and abnormal triangular meshes are removed according to the side length; searching boundary points of the point cloud according to the topological relation of the triangular mesh edges; searching the boundary points of the missing part according to the corresponding relation of the boundary points; filling a plurality of points in the missing part based on spherical projection; and calculating the curvature of the filling point, and performing iteration to enable the curvature to be minimum so as to correct the position of the filling point. According to the method, the boundary points of the point cloud can be effectively detected, the filling points are generated, and the missing parts are repaired, so that the integrity and the accuracy of the point cloud are improved.

The present invention discloses a position error calibration device and a calibration method for an industrial robot. The position error calibration device in the present invention includes a laser ranging component for measuring the three-dimensional coordinates of the target ball at the end of the robot. The laser ranging component includes a laser interferometer, a beam splitter, a two-dimensional position sensitive detector, and a housing; a two-dimensional moving platform for moving the laser ranging component in the X-axis and Y-axis directions. The two-dimensional moving platform includes a lead screw slider module and a grating scale in the X-axis and Y-axis directions; a supporting device for fixing and supporting the two-dimensional moving platform so that it can work stably in three-dimensional space. Compared with a laser tracker, the present invention does not require transformation between a spherical coordinate system and a rectangular coordinate system, thereby avoiding the amplification effect of the angle error of the inner circle grating in the laser tracker. The present invention can directly measure the three-dimensional coordinate values of the reflecting target ball in the measurement coordinate system, has a good calibration effect, and can meet the calibration requirements of industrial robots.

The invention provides a projection transformation method for hexahedral panoramic data to spherical panoramic data, and the method achieves the seamless splicing of panoramic images of six surfaces of a cube and the mapping of the panoramic images to a spherical coordinate system through the determination of a direction vector, the normalization of the vector, the conversion of spherical coordinates, the projection to an equidistant histogram, and an illumination and color correction algorithm. The problems of splicing gaps, deformation, texture distortion and the like in a traditional method are solved. The method is not only widely applied to the fields of virtual reality, augmented reality, panoramic video production and the like, but also greatly expands the application scenes, including but not limited to panoramic roaming, streetscape roaming experience, integrated use of specific roaming plug-ins, seamless embedding on a map platform and the like, and has wide application prospects. Therefore, the display effect of the panoramic data and the immersive experience of the user are remarkably improved.

The invention discloses a robot three-dimensional reconstruction equipment viewpoint planning method and system and computer equipment. The method comprises the steps that a standard three-dimensional CAD model of a to-be-tested aero-engine special-shaped blade is obtained; designing and expanding a voxel state space, and updating the voxel state of the state space by scanning a to-be-detected blade; defining the depth range of the scanner, calculating the radius of the scanner in combination with the size of the to-be-measured blade, representing the position of the scanner by adopting a spherical coordinate system, adjusting the position of the scanner according to the deviation angle, and forming an action space according to adjustable parameters; the position and orientation of the scanner are converted into the angles of a mechanical arm and a rotating table, and a seven-degree-of-freedom measurement motion control system is constructed; and designing a reward function, training the seven-degree-of-freedom measurement motion control system in combination with a reinforcement learning algorithm, obtaining the trained seven-degree-of-freedom measurement motion control system when a training termination condition is reached, applying the system to an actual 3D measurement task, and generating an optimal viewpoint plan to guide robot scanning. And efficient and accurate viewpoint planning is realized.

The invention discloses a vascular respiratory movement map construction method, device and equipment and a medium, and relates to the technical field of medical treatment, the method establishes a vascular digraph based on a topological connection relationship in a vascular structure, and quantifies the overall displacement of a blood vessel and the posture of each branch through the extraction of structure control points and the calculation of branch bending energy. The propagation direction of motion between branch points is defined, and consistency constraint is provided for vascular motion modeling. Vascular deformation in motion modeling is quantified by adopting adaptive deformation compensation, and motion deformation of each section of a branch is represented by using rotation measurement and stretching measurement under a spherical coordinate system of a manifold space. Meanwhile, the bending energy weight is adaptively distributed for each branch based on the vascular graph and the SRVF constraint, and the learning efficiency of the model for local attitude deformation is improved.

The invention relates to the technical field of medical image segmentation, in particular to a voxel-level segmentation method based on a three-dimensional medical image. The technical problem is that a medical image segmentation method in the prior art uses voxels of a fixed size to perform segmentation, which may cause inaccurate segmentation in a sparse or fuzzy region. According to the technical scheme, the voxel-level segmentation method based on the three-dimensional medical image comprises the steps that voxel coordinates under a three-dimensional rectangular coordinate system are converted into coordinates under a spherical coordinate system, the size and shape of curvature voxels are dynamically defined, a curvature voxel grid of a whole image space is constructed under the spherical coordinate system, and the voxel-level segmentation method based on the three-dimensional medical image is obtained. Calculating curvature similarity between each voxel and a neighborhood voxel of the voxel, and combining the similar voxels into a larger clustering unit according to the curvature similarity; according to the method, voxel coordinates in a three-dimensional rectangular coordinate system are converted into coordinates in a spherical coordinate system, a curvature voxel space is constructed, voxel clustering is carried out based on neighborhood curvature similarity, and therefore accurate segmentation of the medical image is achieved.

The invention discloses a land gravity far-area terrain correction method and system based on a digital elevation model. The method comprises the following steps of: performing weighted average calculation on a far first region terrain correction value and a far second region generalized terrain correction value of regular distribution measuring points near irregular distribution measuring points by adopting a bilinear interpolation algorithm on the irregular distribution measuring points to obtain a far region terrain correction value; on the basis of a calculation algorithm of a terrain unit gravitational potential vertical partial derivative of a local rectangular coordinate integral kernel of a measuring point under a spherical coordinate system, high-precision calculation and accumulation are carried out on terrain units one by one, the influence of earth surface bending is considered, and a high-precision and high-resolution digital elevation model can be utilized to the greatest extent. A high-precision digital elevation model represented by geographic latitude and longitude is uniformly subdivided for terrain interfaces of a far first area and a far second area, so that digital elevation units with different resolutions are ensured not to be overlapped or have gaps to the greatest extent, and a high-precision and high-resolution digital elevation model is adapted; and subsequent updating and maintenance of the digital elevation model and the remote terrain correction value library are facilitated.

The invention provides a satellite magnetic measurement data downward continuation method, device and equipment and a medium, and the method comprises the steps: inputting observation data, and converting the observation data obtained during satellite in-orbit measurement from a spherical coordinate system to a rectangular coordinate system; determining a model calculation domain, and generating a series of configuration points in the model calculation domain; normalizing observation data position coordinates, configuration point position coordinates and magnetic field three-component data under the rectangular coordinate system to serve as training data; inputting observation data position coordinates and configuration point position coordinates under the rectangular coordinate system into a neural network model, constructing a loss function based on observation data fitting errors and Laplacian equation physical constraints, and training the neural network model; and according to application requirements, generating a target position coordinate on a target continuation plane or space, inputting the target position coordinate into the trained neural network model, obtaining magnetic field three-component data at the target position coordinate, and realizing high-precision downward continuation.

The invention relates to the technical field of computer vision and image processing, and particularly provides a single-camera panorama splicing system and method, and the method comprises the steps: employing a 12 * 9 checkerboard to shoot a plurality of images at different angles and different distances, and obtaining an internal reference matrix and a distortion coefficient of a camera; adjusting the camera to a position where the optical center coincides with the rotating shaft by adopting an optical center alignment method; driving the camera to rotate, and shooting a plurality of to-be-spliced images covering 360 degrees; and splicing the to-be-spliced images into a complete image by adopting image distortion removal, spherical coordinate system conversion and gradient fuzzy fusion methods. The problems of high hardware cost, chromatic aberration, parallax, low splicing automation degree and the like existing in a multi-camera shooting scheme in the prior art are solved, and low-cost, high-precision and full-automatic seamless panorama splicing is realized through optical center accurate alignment, spherical coordinate system conversion and brightness equalization algorithms.

The invention provides an obstacle prompting method and a vehicle-mounted audio system, and the method comprises the steps: determining a target prompt tone corresponding to an obstacle from a prompt tone library based on data collected by a vehicle sensor, and determining the coordinates of the obstacle in a coordinate system of a vehicle; performing coordinate conversion on the obstacle, and converting the coordinate of the obstacle into a coordinate in a spherical coordinate system taking the listening position as an original point; and rendering the target prompt tone by taking the coordinate of the obstacle in the spherical coordinate system as a sound source coordinate. Proper prompt tones are made for the obstacles according to the data of the obstacles collected by the sensors, so that the accuracy of the prompt tones is improved, and the content and interestingness of the prompt tones are enriched; and the spherical coordinates of the obstacle are taken as the sound source coordinates to carry out prompt tone rendering, so that the effect of prompting the direction of the obstacle through the prompt tone is achieved, the obstacle prompting effect is improved, and the driving safety is improved.

The invention discloses a position error calibration device and calibration method of an industrial robot. The position error calibration device comprises a laser ranging assembly used for measuring three-dimensional coordinates of a target ball at the tail end of a robot, and the laser ranging assembly comprises a laser interferometer, a spectroscope, a two-dimensional position sensitive detector and a shell; the two-dimensional moving platform is used for moving the laser ranging assembly in the X-axis direction and the Y-axis direction, and the two-dimensional moving platform comprises a lead screw sliding block module and a grating ruler in the X-axis direction and the Y-axis direction; and the supporting device is used for fixing and supporting the two-dimensional moving platform, so that the two-dimensional moving platform can stably work in a three-dimensional space. Compared with a laser tracker, conversion between a spherical coordinate system and a rectangular coordinate system is not needed, and therefore the amplification effect of the angle error of the inner circle grating of the laser tracker can be avoided. The three-dimensional coordinate value of the reflection target ball under the measurement coordinate system can be directly measured, the calibration effect is good, and the calibration requirement of the industrial robot can be met.

An efficient synthesis method for a radiation pattern of a conformal array antenna is provided. The method includes: step 1, establishing a field analysis model of the conformal array antenna; determining an aperture field distribution principle suitable for the conformal array antenna, and expanding distribution of an excitation I of an arbitrary curved surface source in a spherical coordinate system according to the aperture field distribution principle; and step 3, establishing an optimization model for the radiation pattern of the conformal array antenna, and performing synthesis of the radiation pattern of the conformal array antenna according to the optimization model. The method greatly improves the synthesis efficiency of a radiation pattern of a conformal array antenna while ensuring that the directional pattern requirements are met.

The invention relates to the technical field of precision measurement, in particular to a method for determining a clamping posture in five-axis detection of a blade disc, a medium and equipment. Comprising the following steps: firstly, acquiring a yaw angle omega and a pitch angle phi of a probe direction required for planning a measurement path of a to-be-measured blade of a blade disc and a measurement boundary direction in a spherical coordinate system, and mapping the yaw angle omega and the pitch angle phi to pixel points corresponding to a global accessibility map (GAM); and according to the inclusion condition of each to-be-measured blade pixel group and the angle constraint curve in the measurement boundary direction in the image, adjusting the blade disc clamping yaw angle and / or pitch angle, and setting the blade disc inclination attitude as the optimal clamping attitude when the angle constraint curve contains the most pixel groups. According to the method, based on a GAM image data structure, clamping optimization is converted into an image processing problem, the constraint relation between the probe direction and the moving boundary can be visually presented, the optimal clamping posture can be automatically planned, the minimum clamping times can be accurately determined, and compared with existing commercial software, the method has more advantages.

The invention provides a shielding influence evaluation method for a radar station. The method comprises the following steps: determining relative coordinates of a single longitude and latitude point of a building in a spherical coordinate system taking the radar station as an original point; taking the building as an obstacle, and judging whether the relative distance between the radar station and the obstacle is greater than a protection range threshold according to the relative coordinates; if yes, height limit calculation does not need to be carried out according to the requirement of the vertical shielding angle; otherwise, determining the altitude limit of the obstacle according to the relative distance; if the obstacle comprises a plurality of longitude and latitude points, repeating the steps for each longitude and latitude point to sequentially calculate all azimuth angles and determine a horizontal shielding angle according to the azimuth angles, otherwise, determining the obstacle width limit according to the relative distance; and determining the comprehensive altitude limit of each longitude and latitude point of the obstacle and the comprehensive horizontal shielding angle or the comprehensive limit width of the obstacle. The invention further provides a corresponding system. According to the shielding influence evaluation method, the labor cost can be reduced, and the calculation precision and accuracy are improved.

The invention relates to the technical field of noise modeling, in particular to a low-altitude aircraft environment noise modeling method and system. Sound source directivity data of the low-altitude aircraft at different positions under the spherical coordinate system are reprojected to a hemispherical surface and then converted into sound source directivity tensors; converting the environmental topographic information and the building geometric information into topographic layout tensors; fusing the advanced features of the sound source directivity tensor, the advanced features of the terrain layout tensor, the frequency features of the low-altitude aircraft at the current moment and the flight height features of the low-altitude aircraft at the current moment to obtain multi-modal potential features at the current moment; and inputting the multi-modal potential features at the current moment into the diffusion model, and outputting a noise intensity graph of the low-altitude aircraft at the current moment. According to the method, complex multi-modal conditions such as noise source characteristics, terrain layout and flight height of the low-altitude aircraft can be accurately captured and fused, and the efficiency, precision and generalization ability of noise modeling are effectively improved.

The invention provides a spaceflight signal simulation test method and device, electronic equipment and a storage medium. The spaceflight signal simulation test method comprises the following steps: acquiring flight path information of a spacecraft under a station center spherical coordinate system; the station center spherical coordinate system is a spherical coordinate system taking the measurement and control station as an original point; determining flight path information of the unmanned aerial vehicle under the station center spherical coordinate system according to the projection of the spacecraft in the target projection plane; the target projection surface is a spatial curved surface on a linear observation path of the measurement and control station and the spacecraft; determining a signal compensation parameter between the measurement and control station and the unmanned aerial vehicle based on the flight path information of the spacecraft under the station center spherical coordinate system and the flight path information of the unmanned aerial vehicle under the station center spherical coordinate system; and performing compensation processing on the analog telemetry signal of the unmanned aerial vehicle based on the signal compensation parameter. The flight path of the spacecraft is simulated through the unmanned aerial vehicle, the correctness of the antenna pointing to the spacecraft can be simulated and verified in the process that the antenna of the measurement and control station tracks and points to the unmanned aerial vehicle, and meanwhile the simulation test accuracy is greatly improved.

The invention relates to a measuring and calculating method for a large-size precise component, and belongs to the technical field of contour measurement. The method comprises the following steps: arranging a laser tracker and a first target ball, establishing a measurement coordinate system, and realizing station transfer from the measurement coordinate system to a global coordinate system by using the target ball; the original point of each measurement coordinate system is optimized; arranging a scanner and a second target ball, and respectively establishing coordinate systems; calculating a conversion matrix of a scanner coordinate system and a target ball coordinate system by using the first target ball; then removing the first target ball and arranging the precision component, and simulating the precision component; selecting feature points on the simulation precision component to calculate a scanning path; finally, a trolley is used for carrying a scanner to scan along the path to obtain global coordinate point clouds of the component, the point clouds are spliced to restore the component, and the size is measured and calculated. According to the method, the defect that a traditional tracking type three-dimensional scanning measurement and calculation technology is large in error is overcome, the pose of the mechanical arm is inversely solved through the calculation path, and the accuracy is improved while automatic measurement and calculation are achieved.

The invention discloses a dimension-level constellation disassembly transmission method based on high-dimensional constellation selective mapping, and belongs to the technical field of optical fiber communication. The method comprises the steps that a traditional high-dimensional constellation is constructed, the number of constellation points needing to be extracted is determined through an entropy limit adaptive tuning function, then needed constellation points are extracted from the traditional high-dimensional constellation, and a shaped high-dimensional constellation is obtained; performing dimension-level disassembly on the shaped high-dimensional constellation to obtain a low-dimensional constellation set; performing phase conversion on the low-dimensional constellation set, and transmitting the converted low-dimensional constellation set to a channel for transmission in a spherical coordinate And receiving the low-dimensional constellation set at a receiving end, combining and restoring the low-dimensional constellation set into a high-dimensional constellation, and performing corresponding judgment on the high-dimensional constellation to obtain bit data. Part of constellation points are selected from a high-dimensional constellation to carry out data bearing and transmission, and the Euclidean distance between the constellation points is increased to reduce the bit error rate. And a high-dimensional constellation is disassembled into a low-dimensional constellation set for transmission in the form of a spherical coordinate system, so that the bit error rate rise caused by relatively large influence of a channel on transmission is avoided.

The invention belongs to the technical field of computer vision and digital media, and discloses a dome-screen film production method and system based on a high-altitude aerial image. Projecting the multi-view aerial video sequence to a unified spherical coordinate system, and constructing a panoramic space with an overlapping region; performing non-rigid geometric deformation processing on the overlapping region of the panoramic space to generate an intermediate image with aligned pixels; calculating the fusion cost of each pixel point in the overlapping region in the intermediate image, and performing path search based on the fusion cost of each pixel point to generate a dynamic suture line; generating an image mask based on the dynamic suture line, performing multi-scale frequency domain adaptive fusion on the intermediate image by using the image mask to generate a fused panoramic image, and remapping the fused panoramic image into a projection format adaptive to dome screen playing to output; and the real reducibility and the manufacturing quality of the dome film are greatly improved.

The invention provides a laser SLAM (Simultaneous Localization and Mapping) navigation method for point cloud processing and pose optimization bidirectional closed-loop regulation, which comprises the following steps: screening a current frame point cloud under a spherical coordinate system by using a previous frame pose uncertainty scalar and a previous frame loop importance scalar and adopting a point cloud screening method to obtain a current frame reserved point cloud; judging whether the current frame is a key frame or not based on the reserved point cloud of the current frame, storing the current frame to a key frame set only when the current frame is the key frame, and obtaining a current optimal pose and a pose uncertainty scalar of the current frame by adopting a pose optimization method based on the key frame set; the current optimal pose is used as a current positioning result of the navigation system.

The invention discloses a transcranial magnetic stimulation head target point pose determination method and device and a medium. Relates to the field of magnetic stimulation treatment equipment, and solves the problems that a mechanical arm is not reachable, the posture is not stable or the mechanical arm interferes with the surrounding environment due to the fact that only a unique target posture is determined in the transcranial magnetic stimulation treatment process. The method comprises the following steps: firstly, establishing a head three-dimensional model, determining a three-dimensional coordinate and a unit normal vector of a target spot, converting the head three-dimensional model into a spherical model, establishing a spherical coordinate system, and simultaneously dividing into a plurality of non-overlapping space partitions; calling a corresponding rotation angle mapping strategy to generate a plurality of candidate rotation angles based on a space partition to which a target point belongs, constructing a target pose matrix for each candidate rotation angle, solving a joint angle solution through inverse kinematics, then carrying out constraint condition screening, finally determining an executable pose, and carrying out pose adjustment only by using a rotation freedom degree of a treatment beat around a normal direction. A plurality of pose selection spaces are provided for the mechanical arm, and the execution rate of poses is greatly improved.

The invention relates to the technical field of directional drilling, in particular to a drilling tool well track drawing method based on a spherical coordinate system, according to the method, after a well track coordinate system is established, the spherical coordinate system is combined, multiple sets of well track coordinates are calculated through an iteration method, and finally well track drawing is completed. According to the method, the simplified processing that the drilling tool azimuth angle variable quantity is equivalent to the horizontal angle variable quantity is avoided, so that the well track drawing precision is effectively improved, and data support is provided for well track control and track trend prediction.

The application provides an earth-ionospheric waveguide three-dimensional electromagnetic field prediction method based on a U-Net architecture and a spherical coordinate system physical law and application, and comprises the following steps: constructing a physical information neural network of the U-Net architecture; obtaining multiple groups of ionospheric parameters, generating a three-dimensional electromagnetic field as a label for each group of ionospheric parameters based on simulation simulation to obtain a training sample set; iteratively training the physical information neural network with the training sample set, and in the iterative training process, taking the spherical coordinate system physical law, the ground impedance boundary condition and the ionospheric impedance boundary condition as constraints; stopping iteration and saving the optimal parameters of the physical information neural network when the loss function meets the preset condition to complete training. The scheme takes the spherical coordinate system physical law, the ground impedance boundary condition and the ionospheric impedance boundary condition as constraints to ensure the prediction accuracy of the physical information neural network at the ground boundary and the ionospheric boundary.

A method of assessing the ability to remove powder from an additively manufacturable article includes performing the following for each of a plurality of discrete starting points distributed within a sampling volume: calculating the starting point directional trajectory lengths of a plurality of trajectories of a particle starting from the starting point and moving in an initial direction respectively along a plurality of combinations of a polar angle ϕ and an azimuthal angle θ of a spherical coordinate system about the starting point, and calculating an average of the starting point directional trajectory lengths to give a starting point average trajectory length for the starting point. The method also includes calculating an average of the starting point average trajectory lengths respectively of the plurality of starting points to give a global average trajectory length for the article.

The invention provides an MA joint beam forming optimization method for a low-orbit satellite communication ground station, belongs to the technical field of satellite communication physical layers, and aims to solve the problems that in MA architecture related algorithms, antenna space layout and beam forming strategies cannot be effectively coordinated, but are limited by power consumption, size and mechanical structure constraints of a satellite-borne platform, the implementation difficulty is large, and the cost is high. The method comprises the following steps: establishing a three-dimensional geocentric spherical coordinate system and a three-dimensional geocentric Cartesian coordinate system; establishing a ground station center Cartesian coordinate system; acquiring an average reachable rate, a signal to interference plus noise ratio of a ground station and interference signal gains of other satellites; constructing an optimization problem P1 by taking the antenna position, the antenna spacing and the signal to interference plus noise ratio of the ground station and the interference signal gains of other satellites as constraint conditions; introducing an auxiliary variable, and converting the optimization problem P1 into a quadratic constraint problem p2; and decomposing the secondary constraint problem p2 into a sub-problem P3 to optimize AWV and a sub-problem P4 to optimize APV, and carrying out iterative solution.

The invention discloses an antenna pattern reconstruction method, which relates to the technical field of wireless communication and antenna testing, and comprises the following steps of: selecting two measurement distances in a near-field area, determining a probe angle range and a probe angle interval, and measuring amplitude data of an antenna in a single tangent plane direction to obtain an antenna near-field amplitude pattern on the single tangent plane; copying the antenna near-field amplitude directional diagrams at the two measurement distances measured in the single tangent plane direction to azimuth angles in other spherical coordinate systems, and obtaining 3D antenna near-field amplitude directional diagrams on two spherical surfaces; recovering phases by utilizing the 3D antenna near-field amplitude directional diagrams on the two spherical surfaces to obtain a plurality of near-field directional diagrams of the to-be-tested equipment on the two spherical surfaces; and calculating an antenna far-field pattern of the to-be-tested equipment according to the plurality of near-field patterns of the to-be-tested equipment on the two spherical surfaces. According to the method, system parameters are optimized, so that the measurement cost and time are remarkably reduced, and the method is suitable for rapid air interface (OTA) testing of a 5G large-scale MIMO base station.

A method and device for generating a tool path in a five-axis numerical control machine tool and a storage medium, the method comprising: obtaining a rotation driving command of a tool axis vector in a spherical coordinate system in a plane coordinate system; processing the rotation driving command using a preset optimization model to obtain an optimized rotation driving command; performing B-spline curve fitting using the optimized tool rotation driving command and pre-obtained tool tip point data to obtain a B-spline curve A(u) of the tool tip point and a B-spline curve C(w) of the tool axis vector, wherein u represents a node parameter value of the tool tip point, and w represents a parameter value of the tool axis vector.

The invention discloses a three-dimensional point cloud model noise filtering method for bridge prefabricated parts. The method comprises the following steps of grid division, rasterizing partitioning of a point cloud overall spherical coordinate system and triangular mesh establishment. Plane detection: establishing a neighborhood database, and calculating a normal vector Ni based on a PCA (Principal Component Analysis) method in a block; plane fitting: carrying out plane fitting based on the normal vector and the space coordinates of the detection points, and setting a reference surface and a reference cylindrical surface; weight influence factors are determined, and a normal vector weight value and feature weight value calculation method is defined; determining a bilateral filtering factor; point cloud positioning is optimized based on the bilateral filtering factor; according to the invention, based on Delaunay triangularization and normal vector solution, a reference boundary is obtained by fitting point clouds in a neighborhood, and dual weight factors are introduced, so that processing of various types of noise is realized.