5 results about "Surface gradient" patented technology

The invention provides an online visual detection method and device for flaws of high-speed moving cloth, and relates to the technical field of cloth flaw detection.The online visual detection method comprises the steps that firstly, a response diagram is obtained through time-sharing exposure, a normalized surface gradient modulus is calculated through a normalized difference ratio and logarithm compression, and color albedo interference is eliminated; curvature features are extracted by calculating the absolute value of a Hessian matrix and the square of a Laplacian operator and combined to generate a mixed curvature tensor, and tiny deformation is accurately captured; then manifold unsupervised reconstruction is carried out based on a Gaussian weighted model of a hollowed-out center pixel to obtain an ideal reconstruction tensor, and sample-free adaptive prediction is realized; difference is calculated, a local signal-to-noise ratio abnormal response index is obtained through local statistical window standard deviation normalization, and texture roughness interference is removed; and finally, positioning flaws, carrying out double-threshold judgment by calculating a flaw structure characteristic value and a flaw oil stain characteristic value, and outputting flaw coordinates and categories.

This application relates to a method, system, device, storage medium, and computer program for complex near-surface shallow velocity modeling. The method includes: acquiring preset shot-receiver surface elevation, shot line spacing, and receiver line spacing; smoothing the preset shot-receiver surface based on the shot line spacing and receiver line spacing to obtain a first updated surface at different smoothing scales; smoothing the acquired total static correction to obtain low-frequency static correction and high-frequency static correction; smoothing the first updated surface based on the low-frequency static correction and high-frequency static correction to obtain a first simulated surface; constructing an initial near-surface gradient model based on the first arrival time of each seismic trace, the preset shot-receiver surface elevation, and the first simulated surface, and performing iterative inversion using wave tomography to obtain a final velocity model; and using the final velocity model to perform velocity analysis on each seismic trace to obtain seismic data characteristics. This method improves the accuracy of near-surface velocity modeling and reduces near-surface velocity modeling errors.

The invention provides an ornament arrangement method. The method comprises the following steps: acquiring geometric information of a target three-dimensional model; calculating a surface gradient vector of each vertex based on a position relationship between each vertex of the target three-dimensional model and an adjacent vertex of the target three-dimensional model; calculating a nearest neighbor distance between each vertex and an adjacent vertex thereof, and generating a scaling factor according to the nearest neighbor distance; obtaining a decoration model; and determining the orientation of the ornament model according to the surface gradient vector, and determining the size of the ornament model according to the scaling factor, thereby instantiating and arranging the ornament model to the surface of the target three-dimensional model. By accurately calculating the surface gradient vector and the nearest neighbor distance of each vertex, the geometric feature change of the surface of the target three-dimensional model can be intelligently sensed, so that accurate matching of the orientation of the ornaments and the geometric structure of the surface is realized, and the problems of disordered direction, excessive overlapping or non-uniform distribution of the ornaments are effectively avoided.

A method for forming a surface having anisotropic friction properties by numerically controlled milling is disclosed. [Solution] In this method, machining simulations of milling are performed for combinations of multiple tool orientation parameters, and a height matrix is ​​constructed from the obtained three-dimensional point cloud data. Then, the contact region is extracted, the surface gradient and gradient amplitude values ​​are calculated, and the sets of gradient amplitude values ​​at the contact leading edge during forward and reverse sliding are extracted. Furthermore, the coefficient of friction for forward and reverse sliding is calculated, and an anisotropy evaluation index is calculated based on these. In addition, an anisotropy evaluation index heat map is created, and a ridge line indicating the direction of sensitivity to changes in the anisotropy evaluation index is generated, thereby enabling quantitative prediction and evaluation of the surface friction behavior. This makes it possible to inversely calculate tool orientation parameters under predetermined cutting parameters based on the anisotropy requirements related to the surface micromorphology. By performing milling according to the parameter combination obtained by this method and predetermined cutting parameters, a viscoelastic material workpiece that satisfies the requirements for friction characteristics or sealing function according to the sliding direction can be obtained. The present invention is useful in satisfying the requirements for friction characteristics and sealing function according to the sliding direction in a seal pair.

The invention discloses a three-dimensional surface reconstruction method and device based on a visual tactile image, and the method comprises the steps: obtaining a to-be-detected visual tactile image of a target object through a visual tactile sensor; for any target pixel point in the visual tactile image to be detected, obtaining normalized coordinates and RGB (Red, Green and Blue) information of the target pixel point; performing position feature enhancement processing on the normalized coordinates of the target pixel points to generate a multi-frequency position vector; splicing the multi-frequency position vector with the RGB information to generate enhanced features; on the basis of the enhanced features, predicting a gradient field by using a lightweight network structure, and generating a surface gradient corresponding to the target pixel point; and reconstructing a three-dimensional surface topography graph based on the surface gradient corresponding to each target pixel point. According to the method, feature enhancement processing and a lightweight network structure are combined, and a synergistic effect of input end high-frequency information enhancement and network end high-efficiency expression capability is realized, so that the calculation amount and the parameter amount can be reduced, and meanwhile, the reconstruction precision of a three-dimensional surface can be improved.