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178 results about "Spherical coordinate system" patented technology

In mathematics, a spherical coordinate system is a coordinate system for three-dimensional space where the position of a point is specified by three numbers: the radial distance of that point from a fixed origin, its polar angle measured from a fixed zenith direction, and the azimuthal angle of its orthogonal projection on a reference plane that passes through the origin and is orthogonal to the zenith, measured from a fixed reference direction on that plane. It can be seen as the three-dimensional version of the polar coordinate system.

Interactive large-screen visualization system and method based on multidimensional data real-time rendering

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.
Owner:BEIJING HANGYUN SCI & TECH CO LTD

Position error calibration device and calibration method for an industrial robot

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.
Owner:CHINA JILIANG UNIV +1

Projection transformation method from hexahedron panoramic data to spherical panoramic data

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.
Owner:Chinese People's Liberation Army Cyberspace Force Information Engineering University

Robot three-dimensional reconstruction equipment viewpoint planning method and system and computer equipment

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.
Owner:HUNAN UNIV

Voxel-level segmentation method based on three-dimensional medical image

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.
Owner:宋莲君

Land gravity far area terrain correction method and system based on digital elevation model

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.
Owner:INST OF GEOPHYSICAL & GEOCHEMICAL EXPLORATION CHINESE ACAD OF GEOLOGICAL SCI

Satellite magnetic measurement data downward continuation method, device, equipment and medium

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.
Owner:GUILIN UNIVERSITY OF TECHNOLOGY

Single-camera panorama splicing system and method

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.
Owner:HEBEI UNIVERSITY OF ECONOMICS AND BUSINESS

Efficient synthesis method for radiation pattern of conformal array antenna

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.
Owner:XIDIAN UNIV

Method for determining clamping posture in five-axis detection of blade disc, medium and equipment

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.
Owner:SHANGHAI JIAOTONG UNIV

Shielding influence evaluation method and system for radar station

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.
Owner:EASTERN CHINA AIR TRAFFIC MANAGEMENT BUREAU CAAC

Low-altitude aircraft environment noise modeling method and system

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.
Owner:SUZHOU UNIV

Spaceflight signal simulation test method and device, electronic equipment and storage medium

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.
Owner:CHINESE PEOPLES LIBERATION ARMY UNIT 32039

Dimension-level constellation disassembly transmission method based on high-dimensional constellation selective mapping

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.
Owner:SUZHOU VOCATIONAL UNIVERSITY (SUZHOU OPEN UNIVERSITY)

Method and system for making dome-screen film based on high-altitude aerial image

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.
Owner:SHANGHAI HENGTIAN YIDA ADVERTISEMENT TRANSMISSION CO LTD

Laser SLAM (Simultaneous Localization and Mapping) navigation method for point cloud processing and pose optimization two-way closed-loop adjustment

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.
Owner:JIANGSU UNIV OF SCI & TECH

Transcranial magnetic stimulation head target point pose determination method and device and medium

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.
Owner:ANYANG XIANGYU MEDICAL EQUIP

Drilling tool well track drawing method based on spherical coordinate system

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.
Owner:CHINA UNIV OF PETROLEUM (EAST CHINA)

Earth-ionospheric waveguide three-dimensional electromagnetic field prediction method based on u-net architecture and spherical coordinate system physical law and application

PendingCN122174701ADesign optimisation/simulationConstraint-based CADEarth–ionosphere waveguideAtmospheric sciences
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.
Owner:ZHEJIANG UNIV

MA joint beam forming optimization method for low-orbit satellite communication ground station

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.
Owner:HARBIN INST OF TECH

Antenna pattern reconstruction method

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.
Owner:SOUTHEAST UNIV

Method and device for generating tool path in five-axis numerical control machine tool and storage medium

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.
Owner:TSINGHUA UNIVERSITY +1

Three-dimensional point cloud model noise filtering method for bridge prefabricated parts

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.
Owner:JSTI GRP CO LTD +1

Method and device for processing position data in virtual space

ActiveCN114053702BImage analysisVideo gamesPattern recognitionSpherical space
The present invention discloses a method and device for processing position data in a virtual space. This method relates to the field of data processing technology and aims to address the problem of poor position processing accuracy in existing virtual world spatial scenes. The method primarily comprises: displaying a virtual spherical space containing a target object, the virtual spherical space being created based on a spatial spherical coordinate system; obtaining first position data for a position operation on the target object in the virtual world space; determining third position data of the first position data in the virtual spherical space based on second position data of the visual center point of the virtual spherical space; and displaying the target object at the location of the third position data. The method is primarily used for processing position data in a virtual space.
Owner:BEIJING PERFECT WORLD SOFTWARE TECH DEV CO LTD

An angle positioning method and device based on the geomagnetic field

This invention discloses an angle positioning method and device based on the geomagnetic field, belonging to the field of engineering surveying and quality control. The angle positioning method includes the following steps: S1: Establish a global coordinate system; S2: Establish a local spherical coordinate system for the construction site using magnetic and gravitational fields; S3: Perform zero-point correction on the local spherical coordinate system of the construction site; S4: Calculate the relationship between the global coordinate system and the local spherical coordinate system; S5: Numerically correct the actual measured angle of the local spherical coordinate system. The positioning device of this invention allows workers to hold a handle for close-range direction indication, or the handle can be fixed to a specific location at the site using a fixing claw. In this case, a laser can be emitted from a second laser emitter to indicate the direction, or a thin line can be tied to the second laser emitter on the handle and pulled taut to indicate the direction. This not only makes operation convenient, reduces the workload of measurement, and is not limited by the site during measurement, but also improves measurement accuracy by using laser and a taut thin line to indicate the direction.
Owner:BCEG ROAD & BRIDGE CONSTR

Two-coordinate radar bistatic positioning and tracking method based on nonlinear optimization

The present invention discloses a two-coordinate radar bistatic positioning and tracking method based on nonlinear optimization, which belongs to the field of radar signal processing. Specifically, for a scenario in which two sensors measure the same target, the two-dimensional coordinates of the target in the radar spherical coordinate system are first obtained. Then, virtual pitch angles of the two sensors to the target are set to Φ1 and Φ2 respectively, and the two-dimensional coordinates are converted into virtual three-dimensional coordinates in the radar rectangular coordinate system. The two-dimensional coordinates are further converted into the WGS-84 coordinate system to obtain a relationship equation between the pitch angles Φ1 and Φ2. Based on this, the difference in the coordinate positions of the target in the two sensors is calculated, and the sum of the squares of the differences is minimized as an objective function. The objective function is nonlinearly optimized using the Newton iteration method to solve the optimal pitch angles Φ1 and Φ2. Finally, the optimal pitch angles Φ1 and Φ2 are incorporated into the measurement data (R, θ, Φ) of the sensors, and the three-dimensional position of the target in the WGS-84 coordinate system is obtained using Kalman filtering. The present invention significantly improves the positioning and tracking accuracy.
Owner:BEIHANG UNIV

Method for calculating collision probability of rising section of aircraft in atmosphere based on direct method

The invention belongs to the technical field of aerospace engineering, and discloses a direct method-based method for calculating the collision probability of an ascending section of an aircraft in atmosphere, which comprises the following steps of: rotating a state mean value and an error covariance matrix under a trajectory system of the aircraft to an earth-centered earth-fixed system; under an earth-centered earth-fixed coordinate system, calculating a mean value and a covariance matrix of relative states of the two aircrafts; calculating a collision probability based on a direct method; calculating a collision probability change rate under the spherical coordinate system by utilizing a Legendre polynomial; generating a collision probability change rate sequence based on the process, and calculating an accumulated collision probability sequence; and calculating the maximum value of the change rate of the collision probability and the maximum value of the accumulated collision probability to obtain the normalized collision probability. According to the method for calculating the collision probability of the rising section of the aircraft in the atmosphere based on the direct method, the speed uncertainty of the trajectory is considered, so that the calculation result is more accurate; and triple integration is simplified to double spherical surface integral, so that the calculation efficiency is improved.
Owner:BEIJING INST OF TECH

Motion mapping for continuous gestures using user-centric coordinate system

A movement of a user input component is presented in accordance with a mapping of a user input motion from a user-centric spherical coordinate system to a 2D plane. An input motion by a user is detected. An origin for the input motion is identified in a user-centric spherical coordinate system. An arc length for the input motion is determined based on the identified origin. The input motion is mapped from the user-centric spherical coordinate system to a 2D plane of a user input component, and a movement of the user input component is presented on the 2D plane in accordance with the mapping.
Owner:APPLE INC

Test method and test device for reference signal received power

The application relates to the technical field of mobile communication, in particular to a reference signal received power testing method and a testing device. The reference signal received power testing method of an embodiment of the application comprises the following steps: signals are sent to user equipment from each test point of a spherical coordinate system in sequence. Corresponding reference signal received powers at each test point from the user equipment are acquired. The omnidirectional reference signal received power of the spherical coordinate system is calculated according to the corresponding reference signal received powers at each test point. The application can measure the signal receiving performance of the user equipment based on the reference signal received power.
Owner:BEIJING HONOR DEVICE CO LTD

Unmanned aerial vehicle path planning system based on spherical vector particle swarm optimization algorithm

The invention discloses an unmanned aerial vehicle path planning system based on a spherical vector particle swarm optimization algorithm. The system comprises an unmanned aerial vehicle path comprehensive constraint model module, an unmanned aerial vehicle flight coordinate conversion module and a spherical vector particle swarm optimization algorithm module. The unmanned aerial vehicle path comprehensive constraint model module constructs a complete optimization mathematical model by fusing path length cost, obstacle threat cost, flight height cost and smoothness cost and endowing the cost with corresponding weights, so that a core optimization index of path planning is defined, and a mathematical modeling basis is provided for subsequent modules; the unmanned aerial vehicle flight coordinate conversion module realizes efficient conversion between a three-dimensional rectangular coordinate system and a spherical coordinate system, and provides search space representation compatible with kinematics constraints for an optimization algorithm; the spherical vector particle swarm optimization algorithm module adopts a spherical vector to encode path point positions, combines a dynamic inertia weight and an adaptive learning factor mechanism, quickly generates a smooth path meeting constraints in a three-dimensional environment, and effectively solves the convergence problem of a traditional optimization algorithm in a high-dimensional space. The three modules work cooperatively, and an optimal path scheme meeting actual flight requirements is finally output through a closed-loop process of constraint modeling-coordinate conversion-intelligent optimization.
Owner:ZHEJIANG UNIV