45 results about "Minimum distance" patented technology

The invention discloses a ship intelligent fault diagnosis method and system based on open label space identification. The method comprises the following steps: obtaining a multi-source sensor time sequence signal of a ship system and constructing a training sample set; carrying out feature extraction on the training sample set by utilizing a deep neural network model, and strengthening the clustering characteristics of the features by adopting a center loss function in the training process; training a classifier on the basis of feature extraction and introducing an open set loss function to form a comprehensive objective function; extracting features from a to-be-diagnosed sample, embedding the features, calculating the distance between the to-be-diagnosed sample and a known fault category feature center, and judging an unknown fault through comparison between the minimum distance and a preset threshold value; and outputting a known fault category or triggering an unknown fault alarm according to a judgment result, and dynamically expanding and updating a model knowledge base based on accumulated unknown fault samples. The method can break through the limitation of the traditional closed set hypothesis, effectively identifies the unknown fault type, and achieves the self-adaptive learning and continuous optimization of a ship fault diagnosis system.

The invention discloses a dual-machine target positioning method based on semantic prior and spatial intersection constraint. The method comprises the following steps: 1, acquiring images of a camera 1 and a camera 2, and determining the spatial orientation of a camera coordinate system relative to a reference world coordinate system; step 2, obtaining a target normalized coordinate under a coordinate system of the camera 1; step 3, obtaining a target normalized coordinate under a coordinate system of the camera 2; 4, converting the normalized coordinates of the target into geometric rays in a three-dimensional space; 5, constructing an optimization function with the minimum distance sum of squares; step 6, performing semantic-level foreground and background division on the image content through a YOLOv5 network, and constructing a three-dimensional space feature point library of a semantic background; and 7, performing single-view semantic neighborhood retrieval and depth compensation by using the three-dimensional space feature point library of the semantic background constructed in the step 6, and realizing target three-dimensional positioning in a high-altitude long-distance complex scene. According to the invention, the detection robustness and the positioning precision of the high-altitude long-distance target in the environment are improved.

The invention discloses a wheel disc over-rotation fracture sequence sampling method based on space reduction and electronic equipment, and belongs to the technical field of experimental design and digital twinning. The method comprises the following steps: generating an initial sample set and constructing an initial agent model; dividing concerned and unconcerned areas based on the predicted strain amplitude; constructing a comprehensive sampling criterion for fusing the global precision and the strain amplitude of the model; calculating a rejection domain radius which is adaptively reduced along with iteration; solving an optimization problem with maximization as a target and minimum distance > = as a constraint, and determining newly added sample points; and updating the model and carrying out iteration until a precision convergence condition is met. According to the method, through physical mechanism driving and dynamic space regulation and control, automatic focusing sampling is carried out on a high-strain key area, an agent model with higher local precision can be constructed at lower simulation cost, and the efficiency and accuracy of wheel disc fracture rotation speed prediction are remarkably improved.

The invention discloses a space target collision early warning method based on GPU parallel computing and a J2 perturbation item, aims to solve the problems of high computing complexity and poor real-time performance of existing CPU processing space target collision risk assessment, and provides a multi-stage screening method based on GPU parallel computing and the J2 perturbation item. The method comprises the following steps: reading a TLE and calculating near / distant points and a reference check point at a GPU (Graphics Processing Unit); combining according to C (N, 2) and screening according to epoch, height and geocentric distance; taking a check point state as an initial value in a check interval, and adopting single-precision J2-RK iterative screening to obtain events NJ2pre and tJ2pre; the events are screened by using double-precision J2-RK in front and back check sections, and minimum distances distJ2 and tJ2 are output; and finally, SGP4 / SDP4 is used for parallel actuarial calculation to obtain a minimum distance distDC, a relative speed, a collision probability and the like. The method gives consideration to real-time performance and precision, significantly reduces the O (n) calculation cost, and is suitable for large-scale in-orbit target early warning.

A sealed compression measurement method, a storage medium and an equipment relate to the technical field of automation detection, and solve the problems of low efficiency and poor measurement accuracy of the existing manual measurement method. The method comprises the following steps: S1, fitting models of a measured sealing element and a measurement reference element in a free state according to actual assembly positions of the measured sealing element and the measurement reference element, and cutting two-dimensional sections of the measured sealing element and the measurement reference element; S2, marking the measured sealing element and the measurement reference element; S3, capturing an intersection of the measured sealing element and the measurement reference element; S4, establishing a measurement reference surface of the measurement reference element; S5, capturing a farthest point i of the measured sealing element on a side compressed to the reference surface; and S6, measuring a minimum distance of the point i to the measurement reference surface, that is, a compression amount.

The invention discloses a rendering method of a fragmentation model in a virtual scene and a related device. The method comprises the following steps: for each fragment model included in a fragmentation model in a virtual scene, determining a target frame center point position of the fragment model through a plurality of target frame vertex positions of the fragment model, and determining the maximum distance from the vertex to the center point of the fragment model, namely the maximum collision size; obtaining a minimum distance, namely a distance field value, from the center point of a scene voxel to which the center point position of the target frame in the virtual scene belongs to the scene surface; under the condition of determining that the fragment model collides with the scene surface based on the maximum collision size and the distance field value, adjusting the center point position of a target frame through a direction vector of the distance field value, the moving speed of the target frame of the fragment model and the interval time of adjacent frames to obtain an adjusted position; and rendering the fragment model based on the adjusted position to obtain a rendering result of the fragment model. According to the method, the penetration phenomenon between the fragment model and the scene surface in the rendering result can be avoided, and the rendering effect is improved.

The invention provides an efficient cooperative construction method, device and equipment for simultaneous operation of multiple geophysical prospecting teams, relates to the technical field of seismic prospecting, and aims to solve the problem that the construction efficiency is low under the condition that the distance between shot points constructed by the multiple geophysical prospecting teams in the same time window in adjacent work areas is smaller than the minimum distance of synchronous excitation in the prior art. The method comprises the following steps: integrating adjacent work areas for analysis, calculating the lower limit value of the root-mean-square energy of the upper cannon interference of a conventional production cannon, and drawing a first time distance curve meeting the condition that the upper cannon interference is not greater than that of the production cannon by utilizing a single-cannon data single-cannon energy attenuation time-space domain distribution plane graph of a long-record long-arrangement-point test; according to the seismic data of the work area, obtaining the lowest refracted wave speed, and calculating a second time distance relation curve when the last shot refracted wave does not enter the single shot data; and an area clamped by the first gun loading interference time distance curve and the second gun loading interference time distance curve is used as a distance range of staggered excitation of two guns in adjacent work areas, a blasting time interval is dynamically calculated, and staggered excitation is carried out.

The application discloses a glue coating size measurement method based on semantic segmentation, and technical solution points thereof comprise the following steps: labeling a glue coating sample image and constructing a data set; training a semantic segmentation model based on attention fusion and pyramid pooling; segmenting the glue coating image by using the model to obtain a mask result; traversing pixel points in the mask, and classifying point sets with a gray scale of 1 as glue strip areas and point sets with a gray scale of 2 as workpiece areas; using a region skeleton algorithm to extract the center axis contour of the glue strip and workpiece areas; using a rectangular detection frame to fit the contour to generate parallel lines and calculate the distance between the lines; counting the maximum and minimum distances in all detection frames to determine whether the glue coating process meets the requirements; the method can quickly measure the glue coating, does not need a teaching process, has good real-time performance, strong robustness and is suitable for various glue strip and workpiece scenes.

A method for preventing a collision between sections of a test board (3) movable relative to each other in a test board system (1) is disclosed and described, the method comprising the steps of: providing a simulation model (19) representing the test board (3) and the sections of the test board (3) movable relative to each other, a setpoint value for movement of a first section of the test board (3) is determined, a simulated first section representing the first section of the test board (3) is moved based on the determined setpoint value, a distance between the simulated first section and a simulated second section of the test board (3) representing a second section of the test board (3) is determined, the determined distance is compared to a specified minimum distance, and when the determined distance is equal to or greater than the specified minimum distance, the first section of the test bench (3) is moved based on the determined setpoint value. In addition, corresponding test bench systems, computer programs, and computer-readable storage media are disclosed and described.

This invention provides a method and apparatus for measuring contact wire grooves based on machine vision technology. The method involves placing the measuring device below the contact wire groove to be measured, and the device automatically focusing. The measuring device acquires the original image of the contact wire groove and marks the Region of Interest (ROI) of the original image based on a trained YOLOv5-LiteSE contact wire groove recognition model. The edge of the contact wire groove in the ROI region is obtained in HSB format, and a Hough transform is performed on the obtained edge to obtain the linear equation of the contact wire groove to be measured. The angle values ​​of the two types of linear equations are calculated based on their slopes. The angle values ​​of the two types of linear equations are compared with preset standard angle values ​​for the contact wire groove to complete parallelism detection. The minimum distance between the two types of linear equations is calculated to complete the dimensional detection of the contact wire groove to be measured. This invention solves the problem of low measurement accuracy caused by the inability of existing machine vision measurement to achieve rapid automatic focusing when measuring contact wire grooves in tunnels.

To provide a technique capable of measuring a gear shape error.SOLUTION: The machine tool includes a controller configured to execute an error measurement process. In the error measurement processing, an approach start point and an approach direction of a touch trigger probe held by a tool holding device are determined based on a posture of a gear-shaped workpiece held by a workpiece holding device, an actuator is controlled to move the touch trigger probe from the approach start point in the approach direction, and a center position of a tip ball of the touch trigger probe when the touch trigger probe is brought into contact with a surface of the workpiece by the movement is obtained, the method includes determining a candidate value of an error between a gear shape and a target shape of a gear product, generating a cross-sectional model representing a cross-sectional shape of a tooth surface based on the candidate value, the target shape, and a posture, obtaining a minimum distance between the cross-sectional model and a center position, changing the candidate value, and determining, as the error, a candidate value at which an absolute value of a difference between the minimum distance and a radius of a tip ball is equal to or less than an allowable value.SELECTED DRAWING: Figure 6

The invention belongs to the technical field of point cloud models, and discloses a method and a system for identifying internal and external boundary points of a point cloud contour. The method comprises the following steps: performing plane segmentation on an original point cloud to obtain a plurality of independent plane point clouds; for each plane point cloud, obtaining a projection plane of the plane point cloud through plane fitting, extracting boundary points of the plane point cloud, and projecting the boundary points to the corresponding projection planes; converting the projected three-dimensional boundary point set to an xoy plane to obtain a two-dimensional boundary point set; constructing an envelope rectangle for the two-dimensional boundary point set by using a minimum bounding rectangle algorithm; and performing interval scanning on the two-dimensional boundary point set, calculating the distance from each two-dimensional boundary point to the corresponding rectangular edge in the scanning range, judging the two-dimensional boundary point with the minimum distance as an external boundary point, and judging the other two-dimensional boundary points as inscribed boundary points or redundant points. The method can effectively distinguish inner and outer boundary points.

The invention discloses a path planning method and system based on an improved self-adaptive ant colony algorithm, and the method comprises the following steps: initializing, loading traveling salesman problem instance data of a plurality of places based on basic parameters and dynamic parameters of the improved self-adaptive ant colony algorithm, constructing a distance matrix between the places based on Euclidean distance, and performing path planning on the distance matrix. Initializing a symmetric pheromone matrix; iterative optimization is carried out, each ant starts from a randomly selected initial site, a complete path is constructed step by step through an improved state transition probability rule, the path length of each ant is calculated, and the current iterative optimal path and the length thereof are recorded; iteration is terminated, and when the number of iterations reaches the preset value, the algorithm stops running; according to the method, statistics is carried out on results of multiple rounds of operation, the average optimal distance of the multiple rounds of operation and the minimum distance in the multiple rounds of operation are obtained, namely, the optimal planning path is obtained, a self-adaptive volatilization mechanism is introduced, the pheromone volatilization rate is dynamically adjusted according to the number of iterations, and the local optimum problem is solved.

This invention discloses a spectral coding optimization method and imaging system based on the minimum distance in the coding space. The core of this invention lies in proposing a design criterion that maximizes the minimum Euclidean distance between the corresponding vectors of any two different spectral samples in the coding response space. This directly improves the separability of different spectra at the detector end from a geometric perspective, thereby enhancing the system's robustness to noise and disturbances. To efficiently solve this non-convex optimization problem, this invention proposes a global-local joint optimization strategy. The spectral encoder structural parameters optimized based on this method can be applied to computational spectral imaging systems. This system, through encoder modulation, signal detection, and sparse reconstruction, ultimately outputs a spatial-spectral three-dimensional data cube of the target object. This invention effectively overcomes the shortcomings of traditional design criteria that do not directly consider geometric separability and the tendency of single optimization methods to get trapped in local optima, significantly improving the system's reconstruction accuracy and stability.

The invention relates to a small sample intention recognition method based on multi-view logistic regression, belongs to the technical field of artificial intelligence and natural language processing, and solves the problems that an existing small sample intention classification method is insufficient in example selection, semantic similar intentions are difficult to distinguish and the model generalization ability is limited. According to the technical scheme, the method comprises the steps that semantic embedding processing is conducted on training data and query statements, cosine similarity is calculated, the size K of an initial support set is dynamically determined based on semantic uncertainty, first K examples are selected to form the initial support set, a multi-view logistic regression model is applied to conduct embedding space discriminative conversion, similarity is recalculated, and the initial support set is selected. And carrying out diversity constraint optimization on the final support set by adopting a maximum and minimum distance selection algorithm, and constructing large language model input for intention recognition. According to the method, the most discriminative and representative examples can be automatically screened, and the classification accuracy, robustness and generalization ability are improved.

The application relates to a high-dimensional QAM signal modulation system and a modulation method based on a clustering algorithm sequence extraction, and the method comprises the following steps: firstly, generating an original high-dimensional constellation point set and an index bit stream; then, calculating the clustering number according to a target source entropy and a sequence length, and clustering the original constellation points by adopting a K-means++ algorithm, selecting the sequence closest to the center in each cluster as a representative sequence to form an optimized constellation point set; then, mapping the index bit stream to the index of the representative sequence, extracting the corresponding QAM symbol sequence according to the index; finally, modulating the sequence into a time domain signal and transmitting, and at the receiving end, calculating the Euclidean distance between the received signal and all the representative sequences, identifying the sequence according to the minimum distance criterion and restoring the index bit stream. The application can significantly improve the noise resistance and the spectrum efficiency, controls the system complexity, and has great practical value in adapting to high-speed and high-reliability communication scenes.

The invention discloses an automobile multi-source data time alignment and fusion method and system. The method comprises the steps of obtaining first data and second data with non-uniform time references, and performing standardization processing on time; in the second data, window data are extracted from each candidate position through sliding window search, time coverage is judged, the window data are resampled to a first data time point, and a similarity distance is calculated by adopting a dynamic time warping algorithm; selecting the position with the minimum distance to establish a time mapping relation; and performing data fusion to generate fused data covering the complete or partial time range of the second data. The system comprises a data acquisition and preprocessing module, a sliding window matching module based on dynamic time warping, a time alignment relationship establishment module, a data fusion module and a data output module. According to the method, the relation between the time type and the sampling frequency of the data is not limited, universality is achieved through self-adaptive resampling, and the problems that in the prior art, the requirement for data characteristics is harsh, and the application range is narrow are solved.

The application discloses a finite element parameterized modeling method and system for small and medium span bridges, comprising: obtaining bridge design parameters; determining cross-section geometric parameters according to the type of the main beam; determining the in-bridge direction coordinates of the inter-beam connecting unit according to the arrangement rule of the inter-beam connecting unit and removing the duplicate coordinates; taking the removed coordinates as control nodes, encrypting the nodes of each main beam according to the span, and generating the in-bridge direction node sequence of the main beam; calculating the cross-bridge direction coordinates of the main beam according to the transverse arrangement parameters of the main beam, and pairing the in-bridge direction coordinates and the cross-bridge direction coordinates to generate the node sequence of the main beam; positioning the constraint nodes in the in-bridge direction node sequence of the main beam by using a minimum distance matching algorithm, and applying boundary conditions at the constraint nodes; generating a data interface file that can be analyzed by finite element analysis software, and generating a finite element reference model after analysis; the application supports batch processing, significantly improves the modeling efficiency and standardization level, and is suitable for the rapid construction of finite element reference models in the health monitoring of a large number of small and medium span bridges.

The invention provides a sphericity error evaluation method based on a cone search algorithm. The method comprises the following steps: A, sampling to obtain coordinates of a collection point; calculating a least square ball center coordinate based on the acquisition point coordinate, and then calculating to obtain a least square ball error; b, constructing an auxiliary ball, determining coordinates of search points of the auxiliary ball, calculating the distance from each collection point to the search points, and solving a range value between the maximum distance and the minimum distance; searching point coordinates corresponding to the minimum value and the second minimum value in the range values are found; c, constructing a cone model, obtaining a cone search point, and calculating a quasi-sphere center coordinate; d, calculating a sphericity error f1 value and a sphere center coordinate of a '3 + 2 'structural form of a minimum containing area method based on the quasi sphere center coordinate; e, calculating a sphericity error f2 value and a sphere center coordinate in a '2 + 3' structural form based on a quasi sphere center coordinate calculation method; and F, comparing the f1 value with the f2 value, and outputting a minimum value of the f1 value and the f2 value as a sphericity error evaluation result. According to the method, the sphericity error evaluation efficiency and precision can be remarkably improved.

Systems and methods to perform non-contact radial runout measurement are provided. A system includes a data processing system and a distance sensor distally positioned along a radial axis from an item mounted via an axial axis to a mounting structure. The sensor is configured to generate distance data indicative of distances to a surface of the item during a rotation along a rotation axis and to transmit the distance data to the data processing system. The data processing system can receive the distance data indicative of distances, parallel to the radial axis; obtain, in response to receiving the distance data, a minimum distance and a maximum distance of the plurality of distances; generate a radial runout of the item based on a difference between the minimum distance and the maximum distance; and provide, via an interface, an indication of the radial runout of the item.

The application discloses a method, device and equipment for removing hanging points in road data, and relates to the technical field of image processing. The method comprises the following steps: determining a first hanging point set based on acquired first road data; wherein the first hanging point set comprises a plurality of hanging points; determining a matching path of the hanging points based on a heuristic search algorithm, wherein the matching path is a path in a path between a road where the hanging points are located and a neighbor point or line of the hanging points, the path has the minimum distance and an included angle with the road where the hanging points are located within a first angle range; and processing the hanging points and / or the matching path according to a spatial position relationship of the hanging points, and removing the hanging points. The scheme of the application solves the problems of long cycle, high cost, low accuracy and poor universality of the existing method for removing hanging points.

The invention belongs to the technical field of optical measurement, and particularly relates to a high-precision miss distance rapid measurement method for multiple targets. The method comprises the following steps: firstly, identifying a multi-target two-dimensional angle track in a single observation station, and carrying out inter-station track matching calculation on the multi-target two-dimensional angle tracks of any two selected observation stations to obtain a multi-target three-dimensional space track, namely, taking the inter-station two-dimensional track as an input to obtain a multi-target three-dimensional space track; processing such as intersection and matching at the same time point is carried out by combining the angle measurement precision of each observation station and the like, a multi-target space three-dimensional track is finally obtained, and the minimum space miss distance and the corresponding moment are calculated according to the four-dimensional space-time track data of the main target and each target. According to the method, space trajectory fitting is carried out on multi-target four-dimensional space-time discrete data with time as an independent variable, the minimum distance value between each secondary target and the main target at the same moment is calculated according to a partial derivative solving result of a fitting equation, and high-precision calculation of the multi-target miss distance is achieved.

The invention discloses a resolution improvement limit derivation method. The method comprises the following steps: converting an echo signal into an echo signal matrix expression under a geometric diffraction model; echo vector probability distribution is obtained under the condition that preset noise is Gaussian complex noise, and an echo likelihood function is obtained according to the echo vector probability distribution; calculating a Fisher information matrix of the scattering center parameter; obtaining CRLB of the scattering center parameters according to the Fisher information matrix of the scattering center parameters; obtaining the minimum distance between the two scattering centers according to the pole phase difference of the two scattering centers under the pole model; obtaining the phase difference of two poles in the first sub-band and the phase difference of two poles in the double sub-bands according to the minimum distance between the two scattering centers; and obtaining a resolution improvement limit according to the phase difference minimum value of the two poles in the first sub-band and the phase difference minimum value of the two poles in the double sub-bands. The invention solves the problem that the existing resolution improvement limit is only suitable for a point scattering center and has a narrow application range.

The application discloses a loader working device motion interference checking algorithm and system, comprising the following steps: obtaining each hinge point coordinate and corresponding parameters such as pin shaft diameter at the position; generating a two-dimensional profile of the working device according to the hinge point coordinate and corresponding parameters such as pin shaft diameter at the position; determining the interference-prone position according to design experience, calculating the minimum distance of the interference-prone curve pair under the current posture; comparing the minimum distance between the calculated curves with the minimum gap value allowed by design, and if the minimum distance of the curve pair is smaller than the minimum gap allowed, recording the length of the dump cylinder and the boom cylinder under the current posture; when the length of the dump cylinder and / or the boom cylinder changes, the position of the profile is updated, and then the above steps are repeated until the motion is completed. Compared with the prior art, the product development efficiency can be effectively improved.

The invention discloses a meteorological feature-oriented wind-solar load time sequence scene generation method, which belongs to the technical field of power system dispatching optimization, and comprises the following steps: according to discretely acquired time sequence meteorological data and time sequence wind-solar load data, performing expansion based on a pre-trained TimeGAN model to generate an expansion data set; key meteorological features are selected based on the similarity between the candidate meteorological features and the corresponding wind power, photovoltaic and load time sequences; and forming sample vectors by using the key meteorological features and the time sequences of the wind power, photovoltaic and load corresponding to the key meteorological features, clustering the sample vectors, taking the category with the maximum absolute value of the Kendall correlation coefficient as a unified index, calculating the Euclidean distance between clusters, and iteratively pairing according to the minimum distance principle to generate a wind-solar load time sequence scene. According to the method, the problem of scene distortion caused by the fact that meteorological characteristics cannot be utilized to generate a more accurate wind-light load time sequence scene in the prior art is solved.

This invention provides a method, electronic device, and storage medium for determining false flight trajectory point data, relating to the technical field of false flight trajectory point data determination. The method includes: acquiring a normalized flight data list set D; determining the flight data group corresponding to each type of normalized flight data for each trajectory point, to obtain a flight data group list set EA corresponding to D; and processing EA... j Perform linear fitting to obtain the linear regression function y(i); obtain EA. j The minimum distance between the coordinate point corresponding to each flight data set and y(i) is used to obtain EA. j The corresponding minimum distance list LT j If each minimum distance list set in LT satisfies the preset second judgment condition, then the data corresponding to the latest n flight trajectory points is determined to be false trajectory point data. This invention can prevent false flight trajectory point data from being used by the data monitoring platform, which could lead to data monitoring anomalies on the data monitoring platform.

The invention discloses a new energy output scene reduction method and system, and the method comprises the steps: carrying out the clustering center selection of original scenes in an obtained original scene set according to a density priority principle, obtaining a first initial clustering center, and carrying out the reduction of a new energy output scene based on the first initial clustering center; gradually selecting other initial clustering centers in the original scene by adopting a maximum and minimum distance principle; the maximum and minimum distance principle avoids the situation that initial clustering center selection may be too adjacent, an object with the Euclidean distance as far as possible is selected as the clustering center, the stability of the clustering center is improved, it is ensured that the minimum distance between the newly selected center and all the selected centers is maximized, and the clustering accuracy is improved. Therefore, all the initial clustering centers are uniformly and dispersedly distributed in the data space as far as possible, and the situation that the initial centers are too adjacent in a traditional method is avoided. According to the strategy, the representativeness and stability of the clustering center are effectively improved, and time correlation decoupling caused by improper selection of the initial center is prevented.

The invention discloses a machine learning driven airfoil design method, equipment, a medium and a program product, and the method comprises the steps: (1) building a mathematical model of the floating amount and the lift-drag ratio of an airfoil node by taking weight and rigidity as constraints; (2) establishing an airfoil profile population based on space filling Latin hypercube sampling; (3) calling DE mutation operation and a maximum and minimum distance screening method by adopting uniformly distributed random numbers to generate a first generation of sub-populations; (4) optimizing by adopting an interior point method to generate a second generation sub-population; and (5) selecting airfoil profile filial generations according to an error-driven adaptive screening strategy assisted by the agent model, evaluating the airfoil profile filial generations, selecting an optimal individual from the airfoil profile filial generations according to a feasibility rule, judging whether an optimization result of the optimal individual reaches the standard or whether the current judgment frequency reaches the maximum judgment frequency, if so, outputting an optimal variable parameter, and if not, returning to the step (3). According to the method, an evolutionary mechanism adaptive to airfoil constraint calculation difference is designed to reduce calculation cost, so that the design period of airfoil lift-drag ratio optimization is shortened.

The present application belongs to the field of optical measurement technology, and particularly relates to a high-precision off-target amount fast measurement method for multiple targets. The method is as follows: firstly, the two-dimensional angle trajectory of multiple targets in a single station is identified, the two-dimensional angle trajectory of multiple targets of any two selected stations is calculated for inter-station trajectory matching, the three-dimensional space trajectory of multiple targets is obtained, that is, the two-dimensional trajectory between stations is taken as input, combined with the angle measurement accuracy of each station, the intersection and matching of the same point are processed, and finally the three-dimensional space trajectory of multiple targets is obtained, according to the four-dimensional space-time trajectory data of the main target and each target, the minimum space off-target amount and the corresponding time are calculated. The four-dimensional space-time discrete data of multiple targets is fitted with time as the independent variable, according to the partial derivative result of the fitting equation, the minimum distance of each target and the main target at the same time is calculated, and the high-precision calculation of the off-target amount of multiple targets is realized.

The present application belongs to the technical field of machine tool control, and discloses a control method and system of a five-axis machining center. The angle instruction sequence of the rotating shaft is obtained and is intercepted in sections by using a sliding window. The sub-sequences in each sliding window are respectively decomposed by three-layer wavelet packet, the energy distribution and information energy entropy are obtained and are screened in sections, and the micro-oscillation candidate area is obtained. The tool geometric model and local surface data are called, the minimum distance between the swept envelope surface and the theoretical machined surface is obtained, and the micro-oscillation candidate area is verified in combination with the safety threshold. The oscillation fundamental frequency and peak-to-peak value of the micro-oscillation candidate area passing the verification are extracted, and the frequency band is classified in combination with the mechanical resonance frequency table of the rotating shaft. The fitness function is solved according to the classification result and the improved particle swarm algorithm, and the optimal suppression parameter is obtained. The optimal suppression parameter is input to the five-axis machining center for machining control, which is conducive to balancing the machining precision and efficiency.