72 results about "Point trajectory" patented technology

The invention discloses a radial milling method for an edge head curved surface of a thin walled vane. At first, three-dimensional modeling is carried out on the thin walled vane to be processed, the processing coordinate system of the three-dimensional model of the thin walled vane is adjusted, a vane basin curved surface, a vane back curved surface, a front edge curved surface and a back edge curved surface are respectively extracted, effective processing regions are divided on the vane curved surface and contact point track is designed on the vane basin curved surface and the vane back curved surface, thus obtaining a contact point trajectory covering the whole processing region. Then a non-uniform B sampling curve that connects the trajectory of the vane basin cutter location and the trajectory of the vane back cutter location is constructed on the front edge and the back edge of the vane, and the corresponding cutter-axis vector and the cutter location are calculated. As only the vane basin curved surface and the vane back curved surface are involved in the cutting in the processing process, the front edge curved surface and the back edge curved surface are processed separately, thus avoiding over-cutting caused by intensive cutter locations on the front edge and the back edge and violent change of the cutter-axis vector. The processing precision can be improved to 0.05 to 0.10mm from 0.24 to 0.60mm of the prior art, and the processing efficiency can be improved at the same time.

Plane detection and tracking algorithms are described that may take point trajectories as input and provide as output a set of inter-image homographies. The inter-image homographies may, for example, be used to generate estimates for 3D camera motion, camera intrinsic parameters, and plane normals using a plane-based self-calibration algorithm. A plane detection and tracking algorithm may obtain a set of point trajectories for a set of images (e.g., a video sequence, or a set of still photographs). A 2D plane may be detected from the trajectories, and trajectories that follow the 2D plane through the images may be identified. The identified trajectories may be used to compute a set of inter-image homographies for the images as output.

A computer implemented method of mapping of multiple regional center point trajectory movements of cavity walls is provided in which images are acquired and a region-of-interest is identified in each of the images. The region-of-interest is divided into a plurality of distinct regions and a regional center point for each of the regions is located in the images. For each regional center point, a center point trajectory is determined based on variances in position of the center points from each other in the images. The center point trajectory of each regional center point is decomposed into radial and circumferential components so as to isolate radial component of the center point trajectory for each regional center point in each of the images and radial motion versus time curves are displayed for each regional center point based on the determined radial component for each regional center point in each of the images.

A traffic situation is predicted based on the correlation in the traffic situation between road sections. A base vector generation unit generates the base vectors constituting a feature space representing the correlation between a plurality of links by making a principal component analysis for the necessary time in the past recorded in a necessary time database. A projection point trajectory generation unit records a projection point trajectory of projecting the necessary time in the past recorded in the necessary time database to the feature space in a projection point database. A feature space projection unit projects the necessary time at present to the feature space, and a neighboring projection point retrieval unit retrieves a past projection point in the neighborhood of the concerned projection point from the projection point database, and a projection point trajectory trace unit traces the trajectory of past projection points starting from the retrieved neighboring projection point for a prediction target time width, and an inverse projection unit inversely projects the end point of the concerned trajectory to calculate the predicted value of the necessary time.

The invention discloses a group activity data collection method and system based on multisource space-time trajectory data. The method comprises the steps that a background obtains and preprocesses original mobile terminal signal data and original social software signature data and generates to-be-processed signal data and to-be-processed signature data in consistent with specific formats; the background obtains activity point trajectory data from the to-be-processed signal data, establishes and learns prior information of group activity rules, obtains activity point trajectory data, and obtains activity location data; the background marks activity point trajectory semantic information by employing a Bayesian model and generates an activity space-time trajectory chain according to the activity point trajectory data, the prior information of group activity rules and the activity location data. According to the method and the system, individual activities are deduced by employing the Bayesian model; the influence of the activity type of a former moment on the activity type of a latter moment in the space-time activity trajectory is taken into consideration; and accurate, fast and efficient extraction and collection of wide-range and massive group activities are realized.

The invention discloses an acrophobia evaluation system based on virtual reality and eye movement brain wave detection. The system comprises a test scene design module, a test scene selection module,a data collecting and processing module and an acrophobia judgment module; the data collecting and processing module collects the real-time eye movement gaze point trajectory of a testee entering different test scenes through an eye movement detector, collects the real-time brain wave signal of the testee entering different test scenes through a brain wave detector, processes the brain wave signal, and performs emotion judgment according to the processing result; the acrophobia judgment module judges that the testee has acrophobia and outputs the judgment result if the time duration of an eyemovement gaze point in a set height range is smaller than a set time threshold or the motion judgment indicates that the testee is scared, otherwise, the acrophobia judgment module judges that the testee has no acrophobia, the test scene selection module runs again to select a next test scene until all test scenes are selected, and the judgment result is output.

The invention belongs to the technical field of underground tunnel engineering construction and provides a method for quantitatively predicting the cutter abrasion quality of the heading machine cutter during composite stratum heading. On the basis of tool mass measurement and corresponding tool and tunnel face contact point trajectory calculation, mass line loss indexes MLI of tools at differentpositions are subjected to classification statistics according to strata. After the MLI is normalized into equivalent mass line loss indexes EMLI, a universal prediction model for the equivalent massline loss indexes of homogeneous strata is obtained. The MLI and the corresponding EMLI are clear in physical significance. The equivalent mass line loss index universal prediction model considers both the shareability of independent variables and the prediction precision. The cutter wear quality prediction method based on the equivalent mass line loss index general prediction model is provided. The calculation process is simple and clear. The prediction precision is high. Based on engineering investigation data and construction data, the method is reasonable, high in practicability and beneficial to quantitatively predicting the tool abrasion state, scientifically and reasonably arranging bin opening and tool changing and improving the tunneling efficiency.

The invention provides a simulation checking method for finishing deep-space optical navigation image processing algorithm by virtue of a simulation function. The method comprises the following steps: image processing is carried out on an obtained star point trajectory simulation image, a series of attitude matrixes generated randomly and a node predicted value with errors; in the image processing, the node predicted value with errors is corrected; matching templates are obtained at the periphery of each corrected node pixel by taking each corrected node pixel coordinate as a center, so as to carry out cross correlation to obtain a coordinate of relative pixels among a plurality of fixed star targets, and then the corrected value is compared with a true value to evaluate pixel error for image processing; then, a relative angular moment is calculated, recognition of background fixed stars is carried out by adopting a ditrigon fixed star recognition method according to the relative angular moment, a calculation matrix is formed by a fixed star vector according to the recognition result of the background fixed star, and then according to the matrix operation, the azimuth of target planetoids can be calculated; and finally, the calculated azimuth of the target planetoids is compared with the true azimuth of the target planetoids to obtain deviation.

The invention provides a multi-target point trajectory gathering method for forming a target point trajectory, and aims to provide a multi-target point trajectory gathering method which can be used to effectively separate multiple targets, eliminate interference signals, and accurately form a target point trajectory. The method of the invention is realized by the following technical scheme: after a response signal is received by an interrogation antenna, an interrogator separates overlapping signals based on the sum-difference ratio and the amplitude difference between the front and back edges of signal pulse, and the interrogator uses the amplitude ratio SDR of sum and difference signals to eliminate sidelobe interference signals and part of multipath interference signals according to the characteristics of an antenna pattern; whether two framework pulses are overlapping pulses is judged, and the over-wide pulse of which the front and back edges are inconsistent in amplitude is separated into two framework pulses; a set of data with correct framework and low confidence is decoded; and finally, multiple interrogation results of the same target within the scope of one beam are gathered by a density point trajectory association method. By adopting the method of the invention, the problem that it is impossible to identify all targets as the targets are too dense is solved.

The invention discloses an impeller machining tool path global optimization method, which comprises the following steps: S1) carrying out discrete triangularization on an impeller model and a tool model; S2) planning a trajectory of contact points between tools and an impeller, and calculating a tool position point trajectory; S3) judging a reachable direction cone of each tool position point by utilizing interference checking; S4) establishing a global optimization objective function of cutter-axis vector, construction a constrained single-source directed graph and converting the optimization solving problem of the objective function into the shortest path finding problem; and S5) solving the objective function by utilizing a shortest path finding algorithm to obtain an optimal tool orientation. The method can quickly calculate the reachable direction cone of each tool and realizes overall fairing of the cutter-axis vector.

The invention discloses an intelligent shoe sole glue spraying process for avoiding overflow of a glue liquid from an edge. The intelligent shoe sole glue spraying process comprises the specific stepsthat: step 1, data acquisition equipment acquires surface data of a shoe sole to be sprayed with glue on a production line; step 2, a glue spraying robot sprays glue points at the edge of the shoe sole to be sprayed with glue successively at intervals according to uploaded data, wherein the glue points form a closed glue spraying point trajectory circle; step 3, the glue spraying robot sprays glue wires in a shape of candy floss, and sprays different amounts of the candy-floss-shaped glue wires on the surface of the shoe sole precisely according to the shape and structure of the surface of the shoe sole; step 4, and the glue spraying robot completes a spraying operation on the shoe sole. The invention further discloses glue spraying equipment of the intelligent shoe sole glue spraying process. The intelligent shoe sole glue spraying process and the glue spraying equipment can be better applied to glue spraying on shoe soles in different bottom part shapes by utilizing properties of the glue wires, solve the technical limitation of direct use of a spray gun for glue spraying in the prior art, and improve the shoemaking quality and market competition of the production enterprise.

A frame rate improving apparatus and method use a motion trajectory. The frame rate improving apparatus determines forward feature point trajectory information through a feature point, and generates a new intermediate frame by performing backward motion estimation through the feature point trajectory information, thereby generating an interpolated image with high quality.

The invention proposes a scanning radar-based target three-dimensional acceleration motion model calculating method. According to the method, theoretical analysis is carried out at first, and then, adata processing flow is designed. According to the theoretical analysis, the mathematical formula of two-dimensional space target free motion is derived based on acceleration factor analysis; a targetthree-dimensional position information-to-two-dimensional projection matrix and a target two-dimensional position-to-three-dimensional space transformation matrix are obtained by means of derivation;and the influence of calculation step length selection and sampling time point selection on data precision under multi-platform and multi-radar working modes is analyzed. According to the design of the data processing flow, after target motion state and radar working parameter initial setting is completed, the relative polar coordinate position of a target relative to a radar at a sampling time point is calculated through using a target motion model formula, and the normal direction of the radar at the sampling time point is further calculated; whether it is necessary to output a point trajectory is judged through a post-scanning judgment criterion; and after each calculation step length is terminated, target point trajectory position information is corrected based on the error information of the radar, and is sequenced and outputted according to time.

The invention discloses a video action detection method based on central point trajectory prediction. In video spatio-temporal motion detection, each action instance is regarded as a movement track ofthe central point of the action initiator; wherein the trajectory is represented by motion vectors of the central point of the intermediate frame action and the central points of other frame actionsrelative to the central point of the intermediate frame; firstly, features are extracted from a video frame sequence for obtaining central point position prediction and action category prediction of an intermediate frame, then obtaining a motion trail from the central point of the intermediate frame to central points of other frames, and finally generating a detection box of each frame central point to obtain position positioning, thereby obtaining an action category and a positioning result, and completing a space-time detection task on a video clip. According to the anchor-frame-free video action detection method provided by the invention, time-space positioning and classification tasks of actions are completed in the video along a time sequence, and compared with video action detectionwith an anchor frame in the prior art, the anchor-frame-free video action detection method is simpler and more efficient, embodies robustness and high efficiency, and has very strong expansibility andportability at the same time.

The invention provides a hyperspectral image feature extraction method, comprising the following steps: sampling, obtaining pixel point class center; measuring the similarity of pixel points in space,and finding the nearest center point for each pixel point; constructing pixel locus matrix; constructing sample center trajectory matrix; obtaining Eigenvalues and corresponding eigenvectors by decomposing the sample center trajectory matrix, screening the eigenvalues and corresponding eigenvectors, reconstructing the eigenvalues and eigenvectors to obtain the trajectory matrix, and constructingthe transformation matrix , multiplying the transformation matrix by the pixel point trajectory matrix to obtain the reconstructed trajectory matrix; obtaining a new hyperspectral image according to the sequence relation of the reconstructed trajectory matrix. The invention provides the hyperspectral image feature extraction method, which combines spatial information to extract features of the hyperspectral image, so that the new image features have small differences in categories and large differences between categories, which is beneficial to the classification of the images and improves theclassification accuracy.

The invention discloses a foreground trajectory determination method and device based on feedback. The method comprises the following steps: extracting a first predetermined number of feature points from each image frame, and generating feature point trajectories by the match between image frames; screening a feature point trajectory set in which the number of continuously tracked image frames is greater than or equal to a second predetermined number and a foreground trajectory time is determined to be less than a third predetermined number from the feature point trajectories; for the feature point trajectory set, calculating a homography matrix between a current frame and an adjacent frame staring from the first frame, and re-projecting coordinates of each feature point in the feature point trajectory set in the adjacent frame by using the homography matrix; and determining, after the second predetermined number of re-projections, whether the feature point trajectories are determined foreground trajectories according to the re-projection results. By adopting the foreground trajectory determination method and device disclosed by the invention, the feature point trajectories belonging to a foreground object and subjecting to parallax interference can be determined and are determined as the foreground trajectories.