146 results about "Geometric method" patented technology

The invention discloses a robot cartesian space trajectory planning method. The method includes establishing a connecting rod coordinate system and obtaining a forward kinematic equation through a kinetic modeling analysis method; solving the rotating angles of a master control joint and a middle joint according to the vector geometric property and trajectory planning requirement of the robot; seeking a relation equation including introduced variables and solving the rotating angle of the corresponding joint by means of the kinetic modeling analysis method and the solved joint rotating angle; determining whether the pose position can be reached through a vector geometric method when the trajectory planning is carried out in a task space with obstacles; and planning the continuous time variant attitudes of coupled position information to complete the planning tasks. According to the method, extraneous roots can be prevented, efficient solutions can be screened and matched, strange paths can be effectively avoided, and meanwhile, the defects of complex end trajectory planned by the joint space can be prevented and optimized.

The invention discloses a decoupling control method for relative orbits and attitudes of formation satellites, relates to the technical field of the control of the orbits and attitudes of a spacecraft formation, and solves the problems of large satellite calculation amount and low orbit solving efficiency caused by high control dimension of the formation satellites due to serious coupling of the relative orbits and the attitudes of the formation satellites. The method gives two decoupling conditions at first, so that the control of the relative orbits and the attitudes can be designed independently; a thrust vector mobility decoupling constraint condition is introduced to the initialization control of the relative orbits according to satellite attitude mobility constraints indirectly; and during the optimal thrust vector attitude tracking, the possible orientation in space, which meets solar avoidance constraints, of a star sensor optical axis (1) is sought by using a geometric method, and the optimal attitude quaternion and attitude angular velocity are calculated finally by using a double-vector attitude determination algorithm. The method provides important reference value for the control of the orbits and the attitudes of the spacecraft formation.

The invention relates to a triangular gridding based human image face-lift processing method and belongs to the technical field of computer application. By means of triangulation and feature point extraction technology and related geometric method to process the image, the triangular gridding based human image face-lift processing method includes steps of feature point extraction of human faces, triangular gridding, human face outline curve estimation, feature point adjustment, new triangular grid establishing, new image generation and the like. Considering beauty seeking of people and blank of related technology, the triangular gridding based human image face-lift processing method is an automatic digital image face-lift beautifying method, and can realize face-lift beautifying effect simply and quickly by loading in original source image to be subjected to face lift, so that beauty appreciation of people is sufficiently satisfied without undertaking high cost and risk.

The present invention relates to a target tracking cooperative control system and method based on multiple unmanned surface vehicles. The system is formed by connecting a shore-based global location host and a single unmanned surface vehicle control system through a wireless communication module. The method comprises the operation steps of: 1) a formation generation process: employing an auction algorithm to find a multi-target distribution scheme of the multiple unmanned surface vehicles with the maximum income of an unmanned surface vehicle group; 2) motion of the unmanned surface vehicles to perform geometric path planning from any initial state to a target point; and 3) prediction of a target motion track through adoption of a prediction model based on a particle swarm to replace communication abnormal data and perform formation track tracking. The method reduces the calculation amount of the multiple auction processes, achieves the real-time demands of task distribution of the unmanned surface vehicles, employs the path planning method based on the geometric method and the track tracking method based on the neural network to meet the timeliness and the accuracy requirements ofsingle-vehicle track tracking control, employs the motion track predicted by employing the particle swarm optimization to perform compensation, improves the tracking capacity of the unmanned surfacevehicles in the limitation of the communication condition and allows the formation tracking to have high reliability and stability.

The invention relates to a method for realizing precise geometric positioning in a radio communication network, which comprises the following steps: a. screening out the most typical RSSI value of points to be tested in the radio network; b. calculating the distance between the points to be tested and reference points; c. determining the location information of the points to be tested according to the information of the distance between the points to be tested and the two reference points, and the information of the locations of the two reference points; and d. determining the final positioning information of the points to be test according to the location information of a plurality of groups of points to be tested. Compared with the prior zone location and simple weighted average location, the method adopts the most basic geometric method to locate the points to be tested and significantly increases the precision. By using the method of combining the equation of a circle and a trigonometric equation is adopted, a quadric equation set in two variables is transformed into a quadric equation set, thereby simplifying procedure realization. Different processing methods are adopted according to different forms of circle intersection, all situations that are possible to occur are handled wherever possible, thereby ensuring the practicability of the method.

The invention discloses a method for dynamically simulating a human body and clothing in a computer. The simulation effect of different materials is achieved by setting key steps in physical simulation. The method includes the main steps of modeling the human body, processing a human body model and a clothing model, calculating clothing simulation by using mechanics knowledge, correcting after integration, impact detecting and responding. Based on a traditional mass point spring model, a large bending spring is provided to generate a wrinkle effect, corresponding spring parameters are set according to properties of the different materials, a comprehensive correction strategy is adopted in mass point clothing, and a perfect impact response scheme is provided to take characteristics of all the materials into account. Traditional clothing materials are distinguished through a great deal of parameter measurement and geometric methods, the defects that a traditional method is low in efficiency or poor in flexibility are overcome, and the different materials can be dynamically simulated.

The invention relates to composite material structure design in aerospace structures, and provides an efficient optimization method for a variable stiffness composite material plate shell structure. The method includes the steps: performing curve fiber path accurate modeling and buckling analysis on the variable stiffness composite material plate shell structure based on an isogeometric method; building an isogeometric buckling design model of the structure; deriving total analytical sensitivity of buckling response of the variable stiffness composite material plate shell structure; efficiently optimizing fiber paths of the variable stiffness composite material plate shell structure by a gradient-based method to obtain an optimal structure meeting process manufacturing constraints. According to the structure, the carrying efficiency of the variable stiffness composite material plate shell structure can be remarkably improved, and the development period of products is greatly shortened.

The invention discloses a three-dimensional reconstruction method for an indoor dynamic scene based on an RGBD camera. The three-dimensional reconstruction method comprises the steps of RGBD camera calibration, scene image acquisition, feature point extraction, dynamic point detection and elimination, elimination of dynamic points by using a mode of combining a convolutional neural network and a multi-view geometric method, tracking, new key frame insertion, local map optimization, loop detection and the like. By using the three-dimensional reconstruction method, the problems of inaccurate camera pose estimation and dynamic object ghosting of three-dimensional reconstruction in a dynamic scene are effectively solved, and the dynamic region detection step is optimized in time, and the effect of real-time reconstruction can be achieved. A camera track absolute error is used for measurement on a TUM data set, and the root-mean-square error of the camera track absolute error is increased to 0.025 from the previous 0.752.

The present invention belongs to the field of six-degree-of-freedom serial robots, and discloses an identification method of six-degree-of-freedom serial robot tail-end load kinetic parameters. The method comprises the following steps of: 1) establishing a kinetic model of a six-degree-of-freedom serial robot; 2) recording an angle, an angular speed and an angular acceleration of the six-degree-of-freedom serial robot in the motion process, and collecting the motor current information of each joint; 3) obtaining the moment of each joint when the six-degree-of-freedom serial robot is no-load and the actual load moment of each joint when the six-degree-of-freedom serial robot is operated; 4) obtaining the theoretical load moment of each joint with load kinetic parameters; and 5) comparing the actual load moments with the theoretical load moments, and solving load kinetic parameters. The identification method of six-degree-of-freedom serial robot tail-end load kinetic parameters greatly reduces the complexity of multi-freedom geometric method analysis, can effectively simplify the algorithm, can improve the operation speed, and employs a dynamic particle swarm algorithm with a crossover and variation function to effectively prevent particles from falling into a locally optimal solution so as to improve the algorithm accuracy.

The invention discloses an automatic parking path obstacle collision detection method, device and system. The automatic parking path obstacle collision detection method comprises the step that arc-shaped path obstacle collision detection and/or straight line path obstacle collision detection are/is conducted through a geometric method by adopting a path outline, a vehicle outline and an obstacle outline. The automatic parking path obstacle collision detection system comprises a collision detection module used for conducting arc-shaped path obstacle collision detection and/or straight line pathobstacle collision detection through the geometric method by adopting the path outline, the vehicle outline and the obstacle outline. The automatic parking path obstacle collision detection device comprises a memory and a processor used for conducting arc-shaped path obstacle collision detection and/or straight line path obstacle collision detection through the geometric method by adopting the path outline, the vehicle outline and the obstacle outline. By using the automatic parking path obstacle collision detection method, device and system, the obstacle collision detection efficiency can beimproved, the steps can be simplified, and accuracy is high. The automatic parking path obstacle collision detection method, device and system serving as the automatic parking path obstacle collisiondetection scheme can be widely applied to the field of path planning.

The invention belongs to the field of image processing, and discloses an establishment method for establishing a bionic human facial aging model. The method comprises the steps of establishing a human face database, pre-processing an image in the database, extracting a feature point according to the modified ASM algorithm, starting a training program, obtaining the variation mapping between samples in a training library, respectively establishing a shape aging model and a texture aging model, starting a matching program, matching optimal samples for an input human face, selecting the aging age of a target human face, matching the shape aging model and the texture aging model, and synthesizing a final aging face. According to the technical scheme of the invention, the adaptive aging distortion of a human face image is realized. Meanwhile, the image matching is conducted based on the high-dimensional space image geometric method, wherein the texture information and the skin color information are separated. Therefore, the finally distorted image is more vivid.

The invention discloses a machine vision based turn plate angle high-precision online measurement method. Real time image collection is performed on mark round hole points in a turn plate by utilizinga monocular industrial camera. Through vision and image metrology analysis on acquired images, position information of the mark round hole points in the turn plate can be obtained. Then rotation angle information can be calculated through a geometric method. The advantages of the invention achieved in angle measurement include high measurement speed and realization of real time online measurement; avoidance of influence and damage to working piece surface through implementation of a measurement function by adoption of a non-contact technology; and elimination of interference on measurement results due to lighting environment complexity, spray liquid, water spots and the like in a production field through adoption of an improvement algorithm in the highest level.

The invention discloses a two-vector predictive control system and method for a permanent magnet synchronous motor based on a geometric method. The method of the invention comprises the following steps: 1, obtaining a reference voltage vector according to a deadbeat control idea; 2, quickly screening three voltage vectors, including two non-zero vectors and one zero vector, through the position angle of the reference voltage vector as an alternative vector; 3, selecting two voltage vectors from three candidate vector by using a geometric method, and calculating a corresponding duty cycle; and4, converting the selected two voltage vectors and duty cycle into corresponding switching sequence, and output the optimal voltage to the permanent magnet synchronous motor through the inverter. Theinvention can effectively improve the steady-state performance of the permanent magnet synchronous motor, and is easier to understand than the traditional two-vector model predictive control system based on the analytical method, and is easy to extend to the control of the multi-phase motor.

The invention provides a quick and high-precision coordinate calibration method suitable for large-scale seabed transponder arrays. The method comprises the following steps: (1) selecting 3 to 4 transponders for calibrating dynamic geometric geodetic coordinates; (2) completing the measurement of distance among the transponder arrays by using a remote control based acoustic calibration method; and (3) solving the geodetic coordinates of each transponder by using a geometric method. The quick and high-precision coordinate calibration method is characterized in that: by combining a dynamic geometric geodetic coordinate calibration method and the remote control based acoustic calibration method, transponders are managed and controlled by radio/water acoustic remote control instructions, so long-baseline high-precision measurement advantages are maintained, and large-scale long-distance sailing of a working ship can be avoided simultaneously to realize high-efficiency operation.

The invention provides a method for estimating visual gestureattitudes of a moving target for an underwater vehicle. The method comprises the following steps of according to a mathematics model of theunderwater vehicle, enabling sensors (such as a Doppler velocimeter and a bearing and gestureattitude measuring system) to measure the linear speed, angular speed and angle of the underwater vehicleunder a carrier system, so as to obtain state information; obtaining a plurality of known feature points on the moving target, and transforming coordinate systems on the basis of a kinematics model ofthe underwater vehicle, so as to obtain the positions of the feature points of the global system under the image system, thereby obtaining the measuring information; estimating the relative positiondifference distance and moving gestureattitude of the underwater vehicle and the center of the target object by an unscented Kalman filter algorithm. Compared with the geometric method, the method hasthe advantages that the limitation of the layout of feature points requiring to meet the special conditions in the geometric method is overcome; the relative position difference distance and moving gestureattitude of the underwater vehicle and the center of the target object can be accurately estimated.

The objective of the invention is to solve the problem of low precision caused by segmentation of a tooth three-dimensional model by a geometric method in the prior art. According to the technical scheme, the automatic tooth three-dimensional model segmentation method based on curved surface parameterization comprises the steps that after a tooth three-dimensional model is obtained, a curved surface parameterization algorithm is used for mapping a three-dimensional curved surface to a two-dimensional plane, and a tooth two-dimensional image is obtained; Next, through a U-net neural network structure, the two-dimensional image of the tooth is automatically segmented to obtain a segmentation mask of each tooth; And finally, segmentation edge refinement is carried out on the segmented tooth image based on a network flow algorithm, and finally automatic segmentation of the tooth three-dimensional model is achieved. The method can automatically segment the tooth three-dimensional model, andhas high precision and high robustness. The method has a good application effect in an orthodontic CAD system.

The invention discloses an optimal constant guidance command solving method for automatic collision avoidance of an unmanned plane and belongs to the field of unmanned plane flight control technology. Through collision detection based on relative geometrical relationship between an unmanned plane and an invasion machine, a constant guidance command feasible region is firstly solved by a geometric method and overload constraint and collision avoidance is carried out through particle swarm optimization to finish time valuation; then, a objective evaluation function of the optimal constant guidance command is established; and through a traversal method for solving, the minimum guidance command is gained as the objective function, namely the optimal constant guidance command. Automatic collision avoidance of unmanned planes can be achieved, online estimation of collision time is finished, and the lowest energy consumption during the collision-avoiding maneuvering flight process is realized.

The invention relates to a close-range geometric obstacle avoidance method of a wing fixed UAV, and belongs to the technical field of UAV autonomous control. Technical research on autonomous flight of the wing fixed UAV facing such complex environment draws attention of the military gradually due to advantages of high flight speed, low noise and long duration of the wing-fixed UAV. The method is mainly used for close-range geometric avoidance of the wing fixed UAV, laser radars and a geometric method are used, the required deflection angle and the speed of the deflection angle are calculated, and the method has the advantages of rapid response, high reliability and easy operation.

The invention belongs to the technical field of SAR image azimuth resolution ratio improvement and particularly relates to a main and auxiliary SAR image fusion method of a distributed satellite SAR system. The main and auxiliary SAR image fusion method comprises the specific steps of Doppler spectrum envelope correction, radar geometric method based image registration, terrain phase inversion, registration error and residual phase deviation estimation based on an SAR image maximum contrast ratio method, main and auxiliary SAR image fine registration and phase deviation correction and Doppler spectrum splicing. The main and auxiliary SAR image fusion method can conduct effective image fusion on main and auxiliary SAR images so as to improve azimuth resolution ratio and meet the performance requirement of high-quality InSAR processing under the situation that the Doppler spectrum overlapping degree of the distributed satellite SAR system along a long base line of the course approximates to zero.

The invention discloses an SLR station three-dimensional coordinate geometric solution method based on low-orbit satellite satellite-borne GNSS technology. According to the geometric solution method,a GNSS receiver mounted on a low-orbit satellite is used to perform continuous tracking observation, and an undifferenced method is used to perform a precise kinematic orbit determination for the low-orbit satellite; then a satellite laser ranging rangle reflection prism carried in the low-orbit satellite is used to obtain an SLR laser ranging value, the system error correction is carried out on an SLR observation material, the material is converted into a distance between a high precision SLR station and a centroid of the low-orbit satellite, and combined with a precise geometric orbit of a multi-epoh single or multiple low-orbit satellites, according to the distance intersection positioning principle, the three-dimensional geometric coordinates of the ground SLR observation station are calculated by a least-squares method. The satellite-borne GNSS data and SLR tracking observation data of low-orbit satellites are used, a geometric method is used to realize high-precision geometric coordinates solution of the ground SLR observation station, and the solution has the advantage that a complex dynamics model is avoided compared with a classical dynamics solution.

The invention discloses a method for mounting a spherical rib-ring-shaped rope vault structure by a geometric method. The method comprises the following steps: firstly, connecting and suspending a dorsal rope to a pressed ring beam; secondly, connecting the dorsal rope and one end of a central vertical pressure lever of which the lower part is provided with a temporary mounting scaffold, jacking the central vertical pressure lever to a designed elevation of which the elevation point is the vertex elevation of the rope vault; thirdly, connecting one end of a central oblique rope to the dorsal rope, and connecting the other end of the central oblique rope to the other end of the central vertical pressure lever; fourthly, connecting one end of the vertical pressure lever and the dorsal rope, connecting a ring rope and the other end of the vertical pressure lever and connecting one end of the oblique rope and the dorsal rope ring by ring from inside to outside, connecting the other end of the oblique rope, the other end of the vertical pressure lever and the ring rope, and jacking the vertical pressure lever; and finally, tensioning an edge oblique rope, and anchoring the edge oblique rope to the pressed ring beam. The construction method for the rope vault structure only needs to tension the oblique ropes, and can perform mounting according to the numerical values in a table given by the invention so that the structure of the primary extremely-high construction technology can be popularized universally.

Modern decision support methods handle uncertainty or hypothesis about operating conditions, using one of two techniques viz. probabilistic formulation and constraints based method, which is the subject of the present invention. A large number of applications use linear constraints to specify uncertainty. These linear constraints are the set of linear inequalities, which are used to define the demand/supply in the area of supply chains. The set of linear inequalities forms a polytope, the volume of which represents the information content. The present invention deals with the application of computational geometrical methods to find the set theoretic relationship—subset, intersection and disjointness among the polytopes and then present a visualization technique to represent these relationships among polytopes. This invention proposes a decision support system and method to visualize the relationship among the polytopes to help with decision support. A specific embodiment is a Decision Support System for Supply Chain Management.

The invention discloses a large-scale D2D communication method based on an HARQ assisted NOMA. The method comprises the steps of firstly using a random geometric method to analyze the influence of superimposed interference in a D2D network on an outage probability; then deducing a specific expression of spectrum efficiency by using a relation between the outage probability and the spectrum efficiency; and at last building a resource distribution optimization problem based on theoretical analysis results: by reasonably setting the information transmission rates of different D2D users, even occupying the distribution density of the D2D terminal having the same time frequency resources, the spectrum efficiency (throughput capacity or spatial spectrum utilization rate) is maximized and meanwhile the communication reliability is ensured. Simulation and numerical results show that the outage probability of the collaborative application scheme provided by the invention is reduced by 23% thanthat of the non-collaborative mode; in addition, the spectrum efficiency of the method using the non-orthogonal multiple access (NOMA) technology is improved by 17% than that using the orthogonal multiple access (OMA) technology.

The invention discloses a constant geometric method-based composite thin-walled structure inherent frequency design method. The method comprises the following steps of: describing a curved surface shape of each sub-structure of an initial thin-walled composite structure through NURBS, and classifying sub-curved surfaces into a design domain and a non-design domain, changing the shape of the designdomain through movements of control points, and setting positions of the control points as design variables; carrying out grid partition on the structure by adoption of a constant geometric Kirchhoffshell unit, calculating quality and rigidity matrixes of the sub-structures, and carrying out modal analysis; respectively constructing reduction models of the sub-structures by utilizing the first several orders of feature values and feature vectors, forming a reduction model of the composite structure through an immobile interface modal synthesis method, and solving the reduction model to obtain a fixed frequency; and carrying out design sensitivity analysis on the structure to obtain an analysis sensitivity, for a shape design variable, of the fixed frequency, and finally solving a designproblem through a gradient-based optimization algorithm. According to the method, the grid generation process is simplified and the optimization efficiency is improved at the same time.