415 results about "Fiber orientation" patented technology

The invention discloses a method for testing mechanical properties of a carbon fiber reinforced composite material based on image recognition, and relates to the technical field of material tests.The method comprises the steps that a carbon fiber sample of a fiber laying layer is prepared, the width tolerance is controlled through laser cutting, and speckle patterns are sprayed on the surface; training a U-Net + + neural network based on the collected macro / micro image, and analyzing the dynamic change of the fiber angle in real time; fusing the acquired macro / micro image with the dynamic change of the fiber angle, and constructing a constitutive equation of dynamic fiber orientation distribution; and importing the constitutive equation into a finite element model, iteratively optimizing the fiber-matrix interface strength parameters through inversion calculation, performing blind test verification on the sample by using the optimized finite element model, and outputting a cross-scale correlation test report. According to the method, an interface strength parameter is subjected to inversion iteration optimization through a finite element model, a macro-micro strain field, a fiber slip angle and an interface damage parameter are integrated through a cross-scale correlation test report, and full-chain data support is provided for a composite material structure.

The invention discloses a melt spinning cooling system which comprises a spinning box, a cooling cylinder section, a first heating assembly, a second heating unit and a recovery part, the first heating assembly outputs trace hot nitrogen, anti-oxidation protection of melt trickles is achieved, the oxidation risk possibly caused by direct contact of a traditional cooling medium is avoided, and the cooling efficiency is improved. Meanwhile, the second heating unit is matched to regulate and control the temperature of the cooling cylinder section, so that the whole-process temperature accurate control from oxidation prevention to high-temperature natural cooling and the high-temperature natural cooling and cold air supply-free operation process are realized, and the solidification orientation length and process of the melt trickle can be actively lengthened by combining gradient process temperature control; different from the defect of insufficient orientation caused by too fast cooling in the prior art, key conditions are provided for optimization of a fiber orientation structure; due to the coaxially stacked cooling cylinder sections and nitrogen recovery operation, a stable cooling environment is constructed, fiber shaking is avoided, the nitrogen utilization rate and the environmental safety are improved, and the process stability and economical efficiency are balanced.

The invention relates to an intelligent wind power blade defect identification method based on phased array detection, which aims at the anisotropic characteristic of a wind power blade glass fiber reinforced composite material, and can flexibly adjust the sound beam angle, effectively penetrate through the material and inhibit the scattering of an ultrasonic signal through a low-frequency linear array probe with characteristic parameters and an electronic focusing technology. Defects in different directions such as impurities perpendicular to layers, cracks in the fiber direction, wrinkles and the like can be accurately detected, meanwhile, by combining wavelet packet transformation noise reduction and a feature extraction algorithm, the distinguishing capacity of defect echoes and noise in complex materials is remarkably improved, the method is adaptive to complex structures and material characteristics of wind power blades, the application range of the detection technology is expanded, and the detection efficiency is improved. An ultrasonic phased array detection technology and an intelligent algorithm (a K-means clustering algorithm and a YOLOv8 target detection model) are deeply fused, the limitation that traditional detection depends on manual analysis is broken through, and a full-process automatic detection system of data acquisition, feature extraction and intelligent recognition is constructed.

A set of panels including a locking device for locking a first edge portion of a first panel to a second edge portion of a second panel. The locking device includes a horizontal locking device and a vertical locking device. The vertical locking device includes a separate tongue arranged in an insertion groove of the first edge portion and a tongue groove provided in the second edge portion. In a vertically locked state of the first and second edge portions, an abutment member provided at a longitudinal end portion of the separate tongue cooperates with a stop surface of the second edge portion, and a locking portion of the separate tongue cooperates with the tongue groove at a locking surface arranged in a wood-based body layer including wood fibres mainly oriented along a first fibre direction.

The invention discloses an ultrasonic orthogonal scanning measurement method for mechanical properties of a fiber reinforced composite material. The method comprises the following steps: aiming at a composite material unidirectional plate to be detected, fixing receiving (transmitting) points on the surface of one side of a material, positioning the transmitting (receiving) points on the surface of the other side of the material, performing linear scanning along any two orthogonal directions, and recording transmission quasi longitudinal wave and quasi transverse wave time domain waveform signals which are acquired by combining each pair of transmitting and receiving points and are propagated along different paths; establishing an acoustic model for quantitatively describing the quantitative relationship between the ultrasonic trend and the independent elastic constant, thickness and fiber direction angle of the to-be-tested fiber reinforced resin matrix composite so as to simulate an ultrasonic data acquisition experiment and generate a corresponding simulated ultrasonic data set; and updating the independent elastic constant, the thickness and the fiber direction angle value of the composite material by taking the similarity degree between ultrasonic data sets obtained by experiments and simulation as a target function. According to the invention, multi-parameter high-precision in-situ nondestructive measurement of mechanical properties, thickness and fiber orientation of materials can be synchronously realized.

The invention relates to the technical field of composite material repair, in particular to a short carbon fiber technology-based composite material rapid repair method, which comprises the following steps of short carbon fiber pretreatment; preparing a resin matrix; preparing spraying slurry; cleaning the damaged area by laser; scanning the unmanned aerial vehicle; layering and synchronous curing; evaluating the quality of the coating; a chopped fiber spraying technology is applied to the aspect of composite material damage repair, repair time is shortened, cost is reduced, interface bonding strength and fiber orientation are optimized, and the problem that the mechanical property recovery rate of the repaired material is low due to the fact that interlayer stripping or fiber orientation mismatching is prone to occurring in a repair area is solved. And the method can be used for rapidly detecting the thickness of the bubble defect, is suitable for efficient, accurate and light-weight repair of the damage of the CFRP, and is particularly suitable for on-site rapid maintenance scenes.

The invention provides a prepreg thickness uniformity analysis method based on deep learning, and the method comprises the steps: obtaining fiber orientation staggering data in a prepreg multi-layer lamination process, collecting a fiber angle distribution image, and generating a first fiber distribution diagram; extracting fiber orientation staggering characteristics from the first fiber distribution diagram, and separating different angle regions to obtain fiber angle distribution; analyzing the non-uniform resin flow condition according to the fiber angle distribution, and generating a resin flow distribution diagram containing the positions of resin extrusion tiny bulges; based on the resin flow distribution diagram, in combination with gradual adjustment data of lamination pressure of multiple layers of prepregs from low to high, simulating the influence of pressure change on the interlayer fitting degree, and generating a first fitting degree distribution diagram fused with resin flow information; based on the defect position and severity distribution map, combining real-time thickness measurement data to predict thickness distribution deviation caused by interaction of tiny protrusions and bubbles, and generating a first thickness distribution map;

The invention provides a continuous fiber reinforced composite material mould pressing numerical simulation method and system, and the method comprises the steps: S1, building a mould pressing simulation parameterized model based on numerical simulation secondary development by using a programming script; s2, based on the established model, creating an interactive plug-in interface by using a dialog box constructor; s3, the simulation parameters are input into the plug-in to run mould pressing simulation, and a mould pressing simulation result is obtained; s4, establishing a performance analysis model and a warping analysis model according to a mould pressing simulation result and an asymmetrical grid mapping method; and S5, setting corresponding boundary conditions according to actual working conditions, and completing structural performance analysis and warping analysis by using the performance analysis model and the warping analysis model. According to the method, the formed fiber orientation and wrinkle information is mapped into the performance analysis model by using the asymmetrical grid mapping, a set of complete analysis process from manufacturing to response is constructed, and the prediction precision is remarkably improved.

The invention relates to the technical field of equipment processing, in particular to a ship board processing equipment control method and system.The method comprises the steps that the fiber rolling direction of a board to be processed is detected, and an initial processing track is generated in combination with a target contour; inputting the initial processing track into a fiber-track coupling model, and outputting a notch quality prediction parameter; and optimizing an initial processing track according to the cut quality prediction parameters, generating a tear-resistant processing track and controlling an execution mechanism to operate. According to the method, on the basis of coupling of material mechanical properties and machining dynamics, the prediction precision and the local response identification capability are remarkably improved, the notch quality defect caused by small-angle cutting, excessive curvature or vibration excitation is effectively avoided, a scientific basis is provided for trajectory optimization, and the method is suitable for large-scale popularization and application. And the stability and the flexible control capability in the machining process are improved, the cleanliness and the structural integrity of a final plate notch are remarkably improved, and the good industrial application value and the good popularization prospect are achieved.

The invention provides a preparation method of a low-interface thermal resistance carbon fiber composite material based on a low magnetic field orientation technology and carbon fiber orientation equipment. The preparation method comprises the following steps: performing surface modification on short carbon fibers by adopting a non-magnetic carbon fiber surface modifier; mixing and dispersing the surface-modified short carbon fiber, liquid silicone rubber and an auxiliary agent to obtain a carbon fiber composite material; calendaring the carbon fiber composite material to a specified thickness, coating the surface of a rotating table with the carbon fiber composite material for rotary orientation, and preliminarily adjusting the distribution of carbon fibers in the carbon fiber composite material; performing orientation arrangement on the carbon fibers in the carbon fiber composite material again by combining a gradient magnetic field lower than 1T with ultrasonic vibration, wherein the vibration direction of the ultrasonic vibration is consistent with the direction of the magnetic field; and carrying out heating curing molding on the oriented carbon fiber composite material to obtain the low-interface thermal resistance carbon fiber composite material. By regulating and controlling fiber arrangement in stages and combining ultrasonic vibration auxiliary dispersion, carbon fiber dominant direction arrangement is effectively achieved, and the magnetic field intensity requirement is lowered.

The invention discloses a white matter microstructure calculation system and method based on multi-shell diffusion-weighted imaging, and the system comprises a data collection module which is used for obtaining diffusion-weighted imaging and structural image magnetic resonance scanning of a testee; the first data processing module is used for obtaining individual fiber orientation distribution and generating a public template of group-specific fiber orientation distribution at the same time; the second data processing module is used for co-registering the individual fiber orientation distribution diagrams to a common template and segmenting the fiber orientation distribution to obtain white matter microstructure indexes of a whole brain level; the third data processing module is used for obtaining a white matter microstructure index of each anatomical fiber bundle level; and the fourth data processing module is used for obtaining a whole brain fiber streamline based on probabilistic fiber bundle tracking and spherical deconvolution information filtering, and generating a white matter microstructure index of a network level in combination with a prior brain map. By adopting the technical scheme of the invention, quantitative calculation and analysis of the white matter microstructure change of the brain are realized.

The present invention relates to the technical field of concrete material monitoring. Disclosed are a method for monitoring fibers inside concrete, a system, a medium, and a product. The method comprises: acquiring concrete to be monitored; using a capacitance sensor to measure a capacitance value of the concrete to be monitored; inputting the capacitance value of the concrete to be monitored into a dielectric constant calculation formula to obtain a dielectric constant of the concrete to be monitored; acquiring a dielectric constant of target concrete and a dielectric constant of fiber-free concrete; and inputting the dielectric constant of the concrete to be monitored, the dielectric constant of the target concrete and the dielectric constant of the fiber-free concrete into a prediction model to obtain a measurement fiber orientation efficiency coefficient of the concrete to be monitored, and using the measurement fiber orientation efficiency coefficient as a monitoring result of the concrete to be monitored. The present invention can achieve accurate, rapid, and quantitative monitoring of fibers inside concrete.

The invention relates to the technical field of meat slitting optimization, in particular to an intelligent mutton slitting path optimization method and system.The method comprises the following steps that three-dimensional grids and muscle fiber data are obtained, geometry and fiber vectors are fused to calculate an optimal cutting vector field, cutting consistency areas are divided through K-means clustering, and then the optimal cutting vector field is obtained; and determining a regional reference attitude to optimize an internal path, and finally connecting each regional path by using spherical linear interpolation to generate a global cutting path. According to the method, a cutting vector field is generated through fusion of a three-dimensional surface grid and a muscle fiber tensor field and weighting of a geometric normal and a fiber direction, a shape and an internal structure are considered in planning, and continuous smooth transition is formed based on direction similarity clustering and attitude transition trajectory spherical interpolation. And direction coordination and movement coherence of global cutting are kept between areas, deviation and posture sudden change are reduced, the operation stability and slitting precision of a cutter are improved, and machining consistency and structural fidelity are enhanced.

A method for producing a composite material part comprising —a step of producing a preform formed of unidirectional continuous fibers oriented in at least one fiber orientation, —a step of applying non-woven filaments to the preform, and —a step of needling the filaments by means of a needling device comprising a plurality of needles, each needle being provided with a notch extending along a notch axis perpendicular to the main longitudinal axis of the needle, or several notches each extending along a notch axis perpendicular to the main longitudinal axis of the needle, the notch axes being parallel to each other, the needles and the preform being arranged so that the notch axes form a non-zero angle with the fiber orientation.

The invention discloses a composite shell structure topology and fiber angle optimization and equal-interval path generation method. The invention relates to the field of topological optimization and continuous fiber reinforced composite material additive manufacturing, and aims to solve the problem that continuous, equidistant and manufacturable fiber paths are difficult to obtain for a composite shell structure in the prior art. According to the method, based on isogeometric analysis and a Riisner-mindlin shell theory, with flexibility minimization as a target, topology and fiber angle collaborative optimization is carried out on a curved surface shell structure, and a macroscopic topology form and unit fiber orientation are obtained. And extracting an optimized structure boundary and mapping the optimized structure boundary to a parameter space, constructing a grey-scale map through a density field to identify a parameter space boundary, performing fairing by adopting an NURBS curve, and then mapping the optimized structure boundary back to a physical space to form a smooth space boundary. And extracting a structural skeleton in the parameter space and mapping the structural skeleton to a physical space. And based on the smooth boundary and the skeleton, generating a space fiber path meeting the equidistant requirement.

The invention provides a construction method of a fiber concrete fiber bridging numerical analysis model, and belongs to the technical field of fiber concrete. The method comprises the following steps: firstly, establishing a nonlinear slippage constitutive relation of a fiber-matrix interface; secondly, adopting a probability density function to describe anisotropic distribution of a three-dimensional fiber direction angle, simulating randomness of fiber embedding length in combination with logarithmic normal distribution, and introducing a correction factor to quantify interaction between fibers; secondly, mapping a debonding behavior of a microscopic interface to a macroscopic fracture surface through a heterogeneous data transfer protocol to realize seamless coupling of a multi-scale mechanical state; meanwhile, the grid density of the crack tip area is dynamically optimized by combining posterior error estimation and an unstructured hexahedral grid local subdivision technology. By the adoption of the method, the limitation of a traditional model in the aspects of interface behavior characterization, fiber distribution idealized assumption and grid rigid division is effectively solved, and the precision and reliability of fiber bridging effect simulation are remarkably improved.

The invention relates to the technical field of concrete electric pole manufacturing, and discloses a method and system for manufacturing a centrifugal electric pole based on high-performance steel fiber reinforced anti-crack concrete. The method comprises the following steps: collecting raw material performance index data including concrete rheological characteristics, steel fiber distribution and matrix strength data; an electric pole forming multi-scale coupling model is constructed through a material simulation platform; identifying fiber orientation characteristics according to steel fiber distribution data, comparing the fiber orientation characteristics with a fiber distribution-doping demand mapping table, judging whether to adjust a fiber doping strategy or not, and starting a manufacturing parameter decision process if the fiber doping strategy needs to be adjusted; stirring, centrifugal forming and maintenance parameters are extracted from preset rules in combination with performance index data, and details such as the fiber feeding time sequence, the rotating speed and the temperature and humidity gradient are determined; the model is used for simulating the whole manufacturing process, related indexes are output to evaluate the proportion, parameters and quality stability, an instruction optimization process is generated, and the manufacturing scientificity is improved.

The invention discloses a method for establishing a concrete in-situ mesoscopic finite element model based on a CT (Computed Tomography) scanning technology, which is applied to the technical field of mesoscopic simulation of a concrete structure. The method comprises the following steps: firstly, performing XCT scanning on a steel fiber ultra-high performance concrete test piece to obtain a two-dimensional sequence image of an internal structure of the steel fiber ultra-high performance concrete test piece; then, image processing is carried out through Avizo software, and three-dimensional space distribution information of a base body, steel fibers and pores is segmented and extracted; on the basis of the three-dimensional information, a Python program is utilized to generate a finite element mesh, an eight-node hexahedron unit is adopted in a model, and the established model can accurately reflect real mesoscopic characteristics such as fiber orientation, distribution and pore defects.

The invention relates to the field of structural reinforcement and new construction, in particular to a grid material oblique arrangement method for improving the shock resistance of a concrete structure. Comprising the following steps: preparing grids; the grids obtained in the step S1 are obliquely arranged on the surface of a concrete matrix; spraying a bonding layer on the upper part of the grid, so that the grid is bonded with the concrete matrix; scraping mortar on the upper part of the bonding layer; the fiber direction of the grid is changed to be approximately consistent with the main tensile stress direction of an earthquake, so that the fiber efficiently transfers force along a main stress trace line, the shear strength and stability of a concrete structure are improved, meanwhile, concrete is sprayed on the upper portion of the grid, a concrete base body and the grid are bonded together, a layer of mortar is further coated on the upper portion of the bonding layer in a blade coating mode, and the structure is compact. And the grid, the bonding layer and the mortar form a composite protective layer of the concrete structure, so that the stability of the concrete structure can be further improved.

The invention provides a 4D printing path planning method based on fiber orientation and layering sequence, and relates to the technical field of intelligent additive manufacturing, and the method comprises the following steps: designing a two-dimensional plane precursor model according to a target three-dimensional structure, and dividing a deformation area and a non-deformation area; differentiated printing paths and material layouts are planned for different areas, material anisotropy is programmed by setting the movement angle of a printing spray head, and the stacking sequence and the thickness proportion of material layers are controlled; a multi-material composite printing process is adopted, PLA is deposited in the deformation area, and PETG is deposited in the non-deformation area; and finally, applying thermal stimulation at 70-75 DEG C to the component, so that the component is autonomously deformed into a three-dimensional functional component from a two-dimensional plane. Structural integrated manufacturing is achieved, deformation is accurate and controllable, interface combination is reliable, and the light weight and assembly efficiency is remarkably improved.

The invention relates to an intelligent water pressure control method and system for a spunlace non-woven fabric production line, and belongs to the technical field of non-woven fabric production. The method comprises the steps that a fiber web surface image, a fiber web operation speed value, a water flow temperature value and a water pressure fluctuation signal are collected; extracting a fiber distribution density characteristic value and a fiber orientation angle characteristic value according to the fiber web surface image; based on the fiber-water pressure characteristic mapping database, extracting a reference pressure set value; performing frequency domain analysis on the water pressure fluctuation signal, calculating a water flow dynamic viscosity compensation coefficient according to the water flow temperature value, and outputting a comprehensive disturbance compensation vector; inputting the data and a pressure data sequence of a historical preset time period into a long short-term memory neural network model, and outputting a pressure predicted value sequence; and solving an optimal pressure set value, calculating a deviation absolute value according to the optimal pressure set value and an actual pressure detection value, and generating a corresponding water pressure adjusting instruction. The water pressure self-adaptive adjusting device can realize water pressure self-adaptive adjustment in the production process of spunlace non-woven fabrics.

The invention relates to the technical field of curved surface forming of fiber composite materials, in particular to a fiber composite material curved surface multi-point flexible gas-assisted hot pressing pressure control method and system.The method comprises the steps that the fiber direction is obtained by obtaining a design mold, and a deformation mismatching area is determined according to the fiber direction and the obtained airbag deformation direction; according to the method, a deformation mismatch area is obtained, a mismatch dynamic control network is constructed to carry out adaptive adjustment on the deformation mismatch area, local pressure compensation is carried out according to obtained adaptive adjustment feedback, and finally, the mismatch dynamic network is controlled by collecting a mold gap and a gap fitting standard. The problem of deformation mismatch caused by elasticity modulus difference in the primary and secondary directions of the fibers is effectively solved, and the direction and position accuracy of the fibers in the forming process is ensured through dynamic adaptive adjustment of a deformation mismatch area, so that the structural integrity and the mechanical property of a formed object are improved, the pressure can be more accurately controlled, and the production efficiency is improved. The requirements of complex mold curved surfaces and fiber layout are met, and the forming precision is improved.

The invention provides a composite material fan blade bending fracture forecasting method and device based on near-field dynamics and a storage medium, and belongs to the technical field of composite material structural mechanics and computational mechanics, and the method comprises the steps that a dangerous fan blade section under a preset load is determined; fan blade curves are integrated, an initial plane grid is created, polynomial fitting is carried out on discrete points, plane bending is carried out on transition area smoothing, meanwhile, error control is carried out at the large number position of the blade end, fan blade parameterized modeling is achieved, and the laying layer fiber direction is set; boundary conditions are applied, meshless discretization is carried out based on near-field dynamics, a material point motion equation is obtained, a near-field neighborhood is constructed, a family of each material point is searched, and a family member list is formed. The method is applied to bending deformation simulation of a large structure such as a fan blade section and damage simulation caused by deformation, modeling of the laminated plate is simplified by taking a single-layer material point as a laying layer, and natural crack propagation simulation is realized in combination with critical bending angle damage characteristics.

The invention relates to a method for rapidly testing the fracture toughness of a composite material based on a digital image. The method comprises the following steps: S1, preparing a sample; s2, loading the sample; s3, data acquisition; s4, data processing; and S5, calculating the fracture toughness. According to the method, the crack propagation behavior is dynamically analyzed by utilizing high-resolution strain data, and the basic mechanical property of the material does not need to be measured in advance, so that the test process is remarkably simplified; meanwhile, a fracture toughness calculation model constructed based on local strain response breaks through indirect correlation limitation of traditional macromechanical parameters, and can adapt to complex stress states of fracture tips at different fiber orientation angles. Besides, through a standardized strain field analysis framework, universal calculation of cross-sample types and sizes is realized, and a high-precision and high-efficiency solution can be provided for fracture evaluation of FRPC from laboratory standard samples to engineering special-shaped structures.

The invention belongs to the technical field of structure optimization design, and particularly relates to a fiber composite failure safety topological optimization design method and system under a dynamic load, and the method comprises the steps: defining a design domain and related design parameters based on the stress working condition and geometric characteristics of a to-be-optimized structure; carrying out transient dynamic analysis and constructing an equivalent static load for topological optimization, constructing a multi-local failure working condition by taking material density, angle subinterval selection and a fiber angle as design variables, introducing an equivalent directional stiffness matrix continuously related to the fiber angle, and aggregating a multi-working-condition flexibility target by adopting a normalized KS function; failure safety topological optimization iteration and internal and external circulation convergence judgment are carried out in combination with a moving asymptote method, and collaborative optimization of structural topology and fiber orientation is achieved under the dynamic load condition. The problem that it is difficult to consider structural redundancy, failure safety and fiber orientation collaborative design in fiber reinforced composite topological optimization under the dynamic load is solved, and structural safety redundancy and local damage resistance are improved.

The application relates to the technical field of fiber direction simulation, in particular to a composite material fiber direction simulation modeling method and system. The method comprises the following steps: collecting a fiber laying track, correcting the bending radius and unit tangent direction of a path point, and obtaining a fiber laying corrected track; constructing a first direction distribution map according to the tangent direction of each path point in the fiber laying corrected track; analyzing the coverage range of each path in the first direction distribution map on a component curved surface, identifying a curved surface overlapping and crossing area, and calculating an included angle adjustment amount of a direction vector; dividing the first direction distribution map into finite volume units, so as to obtain a second direction distribution map; and performing fiber direction simulation verification according to the second direction distribution map and in combination with preset material anisotropy properties, so as to obtain a fiber direction simulation result. The application is helpful to improve the spatial accuracy of fiber direction modeling and the consistency of simulation prediction.

The present invention relates to the technical field of micro-nano fiber hollow tubes, and particularly to a micro-nano fiber hollow tube and its preparation process, wherein a core layer micro-nano fiber membrane made of a spinning precursor prepared from polymer A and a skin layer micro-nano fiber membrane made of a spinning precursor prepared from polymer B are rolled and collected by a rolling device to form a double-layer micro-nano fiber cylinder with a skin-core structure, and then the core layer micro-nano fiber is completely dissolved by a selective dissolution process to prepare the hollow tube; wherein, by adjusting the rolling and collecting amount of the skin layer micro-nano fiber membrane and the core layer micro-nano fiber membrane by the rolling device at any time, the diameter of the micro-nano fiber cylinder can be adjusted at any time, thereby adjusting the wall thickness and inner diameter of the micro-nano fiber hollow tube. By combining the spinning process, the rolling process and the selective dissolution process, a micro-nano fiber hollow tube with adjustable fiber orientation and diameter, adjustable hollow tube wall, inner diameter and length, and flexible and simple technology is obtained.

The invention discloses a testing device and a testing method for a slippage friction coefficient between prepreg layers, and belongs to the technical field of mechanical testing of composite materials. The device comprises a clamping fixture connected with a mechanical testing machine, a cast aluminum heating plate for providing temperature and fixing a sliding prepreg, two fixing plates for fixing a static prepreg, two sliding table cylinders for providing normal pressure and a supporting bottom plate. The sliding table air cylinder can be controlled by the air compressor to drive the fixing plate to apply normal pressure to the cast aluminum heating plate, and the cast aluminum heating plate can be driven by the clamping fixture to move up and down along the Z axis, so that a friction force-displacement curve and a friction coefficient between prepregs in different fiber directions under different external processing conditions are obtained. The device for testing the interlayer sliding friction coefficient of the prepreg can flexibly test the interlayer friction coefficient of the prepreg in various fiber directions, and ensures the temperature uniformity and the pressure accuracy.

Methods of performing a curve-wise flattening to determine a two-dimensional ply shape are presented. Curves are traced on a first tensor product spline representing a three-dimensional part surface. The curves are reparameterized onto a parametric domain representative of a two-dimensional space. The curves are mapped to a second tensor product spline representing a flat table space while maintaining lengths of the curves between the first tensor product spline and the second tensor product spline in the curve-wise flattening to form a flattened shape, such that resulting table-space flattened curves are parallel straight lines in a desired fiber direction.

The invention discloses a rotator cuff patch and a preparation method thereof, and belongs to the technical field of repair materials. According to the preparation method provided by the invention, the bioactive material is combined, the fibers are gradually transited from random arrangement to aligned arrangement through electrostatic spinning, the difference of fiber orientation structures between the random fiber layer and the aligned fiber layer is effectively reduced, and the bonding force between the layers of the patch is greatly enhanced in cooperation with steam welding treatment; the layering phenomenon is effectively avoided; the tensile strength of the rotator cuff patch prepared by the method reaches 18 MPa, and the rotator cuff patch has excellent mechanical properties, can meet the requirements on flexibility and tear resistance during sewing, can provide enough mechanical support for the rotator cuff in the repair process, and adapts to the complex shoulder movement environment.