Methods, systems, and storage medium for modeling joints with fasteners

Abstract

A method, system, and storage medium for modeling a joint having a fastener. The method includes: receiving a plurality of input parameters of a plurality of components connectable with one or more fasteners; calculating, using the computer, a plurality of second-level parameters based on the input parameters; building a plurality of component models of the component without one or more fasteners based on the second level parameters; subtracting the plurality of bolt holes from the component model; and generating an assembly model by combining the component model with one or more fastener models of one or more fasteners in the bolt hole. The method further includes applying a plurality of boundary conditions to the assembled model; applying a plurality of loads to the assembled model under boundary conditions to generate a plurality of analysis keywords; and generating an input file based on the analysis keyword. The input file is suitable for finite element analysis.

Description

Technical Field

[0001] The present disclosure relates generally to modeling components, and in particular, to modeling joints having fasteners. Background Art

[0002] Unaffected local stresses and strains are the primary cause of cracks found during full-scale fatigue testing. Changing designs and tooling to address issues during the certification process is expensive and causes program delays. Existing modeling solutions are either manual or have sufficiently low fidelity in terms of the ability to capture the three-dimensional contact interactions between fasteners and structural details. The manual model building process also prevents timely evaluation of the full range of manufacturing changes.

[0003] Therefore, those skilled in the art continue research and development efforts in the area of ​​modeling the joint of two or more components having one or more fasteners to improve stress prediction at fastener locations to mitigate risk and do so within program plans. Summary of the invention

[0004] A method for modeling a joint with a fastener is provided herein. The method includes: receiving a plurality of input parameters of a plurality of components connectable with one or more fasteners; calculating a plurality of second-level parameters based on the plurality of input parameters using a computer; constructing a plurality of component models of the plurality of components without the one or more fasteners based on the plurality of second-level parameters; subtracting a plurality of fastener holes from the plurality of component models; generating an assembly model by combining the plurality of component models with one or more fastener models of one or more fasteners in the plurality of fastener holes; applying a plurality of boundary conditions to the assembly model; applying a plurality of loads to the assembly model under the plurality of boundary conditions to generate a plurality of analysis keywords; and generating an input file based on the plurality of analysis keywords. The input file is suitable for finite element analysis.

[0005] In one or more embodiments, the method further includes rotating a plurality of component nodes of the plurality of component models to align with the optical fiber orientations of the plurality of components.

[0006] In one or more embodiments, the method further comprises calculating a center of curvature of the assembled model.

[0007] In one or more embodiments, the method further includes updating a plurality of component nodes of the plurality of component models based on the center of curvature of the assembly model.

[0008] In one or more embodiments, the method further includes assigning materials to the plurality of part models.

[0009] In one or more embodiments, the method further comprises adding one or more additional models to the assembly model. The one or more additional models include one or more strip models, spacer models, shim models, or a combination thereof.

[0010] In one or more embodiments, the method further includes translating one or more additional models within the assembled model.

[0011] In one or more embodiments, the method further includes rotating one or more additional models within the assembled model.

[0012] In one or more embodiments, the method further includes reading a plurality of input parameters and one or more fasteners from one or more libraries.

[0013] A system for modeling a joint with a fastener is provided herein. The system includes: one or more libraries operable to store multiple input parameters of multiple components and multiple fasteners; and a computer. The computer is operable to receive multiple input parameters of multiple components connectable to one or more fasteners from the one or more libraries; calculate multiple second-level parameters based on the multiple input parameters; construct multiple component models of the multiple components without one or more fasteners based on the multiple second-level parameters; subtract multiple fastener holes from the multiple component models; generate an assembly model by combining the multiple component models with one or more fastener models of one or more fasteners in the multiple fastener holes; apply multiple boundary conditions to the assembly model; apply multiple loads to the assembly model under the multiple boundary conditions to generate multiple analysis keywords; and generate an input file based on the multiple analysis keywords. The input file is suitable for finite element analysis.

[0014] In one or more embodiments of the system, the computer is further operable to rotate a plurality of component nodes of the plurality of component models to align with the optical fiber orientations of the plurality of components.

[0015] In one or more embodiments of the system, the computer may be further operable to calculate a center of curvature of the assembled model.

[0016] In one or more embodiments of the system, the computer may be further operable to update a plurality of component nodes of the plurality of component models based on the center of curvature of the assembly model.

[0017] In one or more embodiments of the system, the computer is further operable to assign materials to the plurality of part models.

[0018] In one or more embodiments of the system, the computer is further operable to add one or more additional models to the assembly model. The one or more additional models include one or more strip models, spacer models, shim models, or a combination thereof.

[0019] In one or more embodiments of the system, the computer may be further operable to translate one or more additional models within the assembled model.

[0020] In one or more embodiments of the system, the computer may be further operable to rotate one or more additional models within the assembled model.

[0021] A non-transitory computer-readable storage medium storing instructions for controlling data processing is provided herein. The instructions, when executed by a processor, cause the processor to perform multiple operations, the multiple operations including: receiving multiple input parameters of multiple components connectable to one or more fasteners; calculating multiple second-level parameters based on the multiple input parameters; constructing multiple component models of the multiple components without one or more fasteners based on the multiple second-level parameters; subtracting multiple fastener holes from the multiple component models; generating an assembly model by combining the multiple component models with one or more fastener models of one or more fasteners in the multiple fastener holes; applying multiple boundary conditions to the assembly model; applying multiple loads to the assembly model under the multiple boundary conditions to generate multiple analysis keywords; and generating an input file based on the multiple analysis keywords. The input file is suitable for finite element analysis.

[0022] In one or more embodiments of the non-transitory computer readable storage medium, the plurality of operations further comprises rotating a plurality of component nodes of the plurality of component models to align with the optical fiber orientations of the plurality of components.

[0023] In one or more implementations of the non-transitory computer readable storage medium, the plurality of operations further include: calculating a center of curvature of the assembly model; and updating a plurality of component nodes of the plurality of component models based on the center of curvature of the assembly model.

[0024] The above features and advantages and other features and advantages of the present disclosure are readily apparent from the following detailed description of the best modes for carrying out the disclosure when taken in connection with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1A to Figure 1B is a flow chart of a method of operation of plug-in modeling code according to one or more exemplary embodiments.

[0026] Figure 2 is a detailed flow chart of calculating second level parameters according to one or more exemplary embodiments.

[0027] Figure 3 is a detailed flow chart of building components according to one or more exemplary embodiments.

[0028] Figure 4is a detailed flow chart of updating a node of a fiber alignment grid according to one or more exemplary embodiments.

[0029] Figure 5 is a detailed flow chart of curvature according to one or more exemplary embodiments.

[0030] Figure 6 is a detailed flow chart of assembled components according to one or more exemplary embodiments.

[0031] Figure 7 is a detailed flowchart of obtaining fastener parameters according to one or more exemplary embodiments.

[0032] Figure 8 is a detailed flow chart for obtaining material parameters according to one or more exemplary embodiments.

[0033] Fig. 9 is a schematic block diagram of a computer-based system according to one or more exemplary embodiments.

[0034] Fig.10 are schematic plan and cross-sectional views of a joint 340 according to one or more exemplary embodiments. DETAILED DESCRIPTION

[0035] Various embodiments of the present disclosure provide methods and / or systems for modeling joints with fasteners. The method includes: receiving input parameters of a component connectable to one or more fasteners; calculating second-level parameters based on the input parameters; and constructing a component model of the component without fasteners based on the second-level parameters. The method also includes: subtracting bolt holes from the component model; generating an assembly model by combining the component model with a fastener model of the fastener in the bolt hole; and applying boundary conditions to the assembly model. The method also includes: applying loads to the assembly model, and generating an input file suitable for finite element analysis based on the response of the assembly model to the loads and boundary conditions.

[0036] In some embodiments, the method may include rotating a component node of the component model to align with the fiber orientation of the component, calculating a center of curvature of the assembly model, and updating the component node of the component model based on the center of curvature of the assembly model. When the design for the joint is specified, the method may include adding one or more additional models to the assembly model. The additional model typically includes one or more strip models, spacer models, gasket models, or a combination thereof. The additional model can be translated and / or rotated within the assembly model. The system typically includes a computer and one or more libraries. The library stores input parameters and fasteners of the component. The computer is operable to receive input parameters of a component connectable to one or more fasteners from the library, calculate second-level parameters based on the input parameters, and build a component model of the component without fasteners based on the second-level parameters. The computer can also subtract bolt holes from the component model, generate an assembly model by combining the component model with a fastener model of a fastener in a fastener hole (or holes), apply boundary conditions to the assembly model, and apply loads to the assembly model. The computer also generates an input file suitable for finite element analysis based on the response of the assembly model to the loads and boundary conditions. The system automates high-fidelity physics-based 3D finite element analysis models and has been shown to provide accurate stresses and be able to capture the impact of manufacturing variations to further reduce risk.

[0037] refer to Figure 1A to Figure 1B , a flow chart of an exemplary method of operating modeling plugin code according to one or more exemplary embodiments is shown. The method (or process) 100 can be implemented by one or more computers and one or more user interface devices (e.g., a monitor with a keyboard and / or a mouse). The method 100 generally includes steps 102 to 156, as shown. The order of steps is shown as a representative example. Other orders of steps can be implemented to meet the criteria of a specific application.

[0038] In various embodiments, the functionality provided by the method 100 is divided between a graphical user interface (GUI) function 102 and a core function 104. The GUI function 102 includes access to a material library 106a, access to a fastener library 106b, a start step 110, a build material / read step 112, an input parameter selection step 114, an input decision box 116, a submit for analysis decision box 150, a job submission step 152, a get job status step 154, and an end step 156.

[0039] The kernel function 104 includes a calculate second level parameters step 120 and a loop step 122. The loop step 122 includes a build component step 124, a fiber orientation decision block 126, an update node of a fiber alignment grid step 128, a bend decision block 130, a curvature update step 132, and an assign material step 134. The kernel function 104 also includes an assemble specimen step 136, an apply boundary condition step 138, an apply load step 140, a write first input file step 142, a solver decision block 144, a convert format step 146, and a write second input file step 148. The calculate second level parameters step 120 receives the input parameters 115 from the input decision block 116 in a receive step 119. The solver decision block 144 and the write second input file step 148 present the input file 145 to a submit for analysis decision block 150.

[0040] The GUI functionality 102 implements a user input selection function and a job status function. The GUI functionality 102 is operable to provide a user with a mechanism for selecting individual (e.g., N) components for modeling a joint and the number, type, and placement of fasteners for holding the joint together. The GUI functionality 102 is also operable to provide a user with a mechanism for determining which jobs to submit for analysis and the status of such jobs running on one or more remote server computers and / or one or more local server computers.

[0041] Kernel function 104 implements a modeling tool for generating one of two types of input files for modeling a joint. In various embodiments, the first type of input file can be an Abaqus / CAE (full Abaqus environment) input file. Abaqus / CAE is a software application for modeling and analyzing (preprocessing) mechanical components and assemblies and for visualizing both finite element analysis results. Abaqus / CAE is developed and available by Dassault Systems, Velizy-Villacoublay, France. In some embodiments, the second type of input file can be an LS-Dyna format input file. LS-Dyna is a general multi-physics simulation software package. LS-Dyna is developed and available by Ansys, Canonsburg, Pennsylvania. In various embodiments, the input file can present the model as a finite element model. In some embodiments, the input file can present the model as a geometric model.

[0042] The material library 106a implements a database of materials suitable for manufacturing joints. The material data in the material library 106a may include, but is not limited to, common homogeneous isotropic materials (e.g., metals) and custom user materials, composite ply elasticity and progressive failure parameters, material models for progressive failure analysis (e.g., Hashin, Helius and extensible to others), and adhesive materials. Other types of material parameters may be included to meet the design criteria of a specific application.

[0043] The fastener library 106b implements a database of fasteners suitable for manufacturing joints. The fastener data in the fastener library 106b may include, but is not limited to, protruding head and countersunk fasteners, bolts, and nuts. Other types of fastener parameters may be included to meet the design criteria of a specific application.

[0044] In step 110, the method 100 begins by collecting (or reading) build materials in step 112 based on the joint design provided by the user. The build material / read step 112 is operable to assemble materials for modeling the joint based on the design provided by the user. The build material / read step 112 establishes the parts, material types, spacers, thicknesses, lengths, widths, fasteners, number and arrangement of holes, patterns, and boundaries for the joint model. In the input parameter selection step 114, fastener parameters from the fastener library 106b are added to the build material parameters. The input parameter selection step 114 is operable to buffer the material parameters and fastener parameters selected by the user.

[0045] A check is then performed at input decision block 116. If insufficient parameters are buffered in input parameter selection step 114, the method 100 returns to input parameter selection step 114 to collect the missing parameters. Once the appropriate parameters are present, the method continues to kernel function 104 (e.g., calculate second level parameters step 120), where calculate second level parameters step 120 receives input parameters 115 via the Yes branch of input decision block 116.

[0046] The calculate second level parameters step 120 is operable to generate second level parameters 121 from the input parameters received from the GUI function 102. Step 122 loops around the build component step 124 to the assign material step 134 for each component in the design configuration of the joint being modeled. The build component step 124 generates an initial version of the component model 125a (e.g., a coupon model 125b, a fastener model 125c, an additional model 125d, a strip model 125e, a spacer model 125f, and a gasket model 125g) based on the input parameter selection step 114 and the second level parameters 121. A check is made in the fiber orientation decision box 126 to determine whether the component includes a mesh with a specific fiber orientation. If a specific orientation is detected, the nodes of the component are updated in step 128 to align with the fibers of the mesh. Thereafter, or if a specific orientation is not detected, another check is performed for the curvature of the component in the bend decision box 130. If curvature is detected, the loop step 122 continues with the curvature update step 132. In a curvature update step 132, the nodes of the models 125a-125g are updated to take into account the curvature. After the nodes have been updated for curvature, or if no curvature is detected, the material of the part is assigned in an assign material step 134. For each part in the joint, the loop step 122 loops around the build part step 124. Once completed, the method 100 continues with an assemble sample step 136.

[0047] In the assemble specimen step 136, the component models 125a-125g are assembled into a specimen to form an assembled model 125h of the joint when constructed and possibly updated. In the apply boundary condition step 138, the boundary condition 139 is applied to the assembled model 125h. In the apply load step 140, one or more loads 141 are applied to the assembled model 125h under the boundary condition 139 to generate an analysis keyword 143. The analysis keyword 143 can be captured in a first input file format (e.g., Abaqus / CAE format). The result data is written (or generated) to the input file 145 by the write first input file step 142. A check is performed in the solver decision box 144 to determine whether the format of the input file 145 written / generated in the write first input file step 142 can be converted to another input file format. If the format of the input file 145 is to be converted, the input file 145 is converted from the first input file format to the second input file format (e.g., LS-Dyna format) by the convert format step 146. Thereafter, in a write second input file step 148 , data in the second input file format is written into (or generated in) an input file 145 (eg, having an LS-Dyna input file format).

[0048] An input file 145 in a first input file format (e.g., written in the write first input file step 142 and determined not to be converted in the solver decision box 144) or an input file 145 in a second input file format (e.g., written in step 148) is presented to a submit for analysis decision box 150. In the submit for analysis decision box 150, if the input file is to be submitted for analysis (e.g., by physics-based three-dimensional finite element analysis), the input file is submitted to one or more computers executing Abaqus / CAE or LS-Dyna simulation software in a submit step 152. During the simulation, a get job status step 154 ​​can provide feedback to the user about the results of the ongoing simulation. After the simulation is completed, or after the simulation is not started according to the submit for analysis decision box 150, the method 100 terminates in an end step 156.

[0049] References Back to References Figure 1A and Figure 1B of Figure 2 , shows a detailed flow chart of an exemplary embodiment of the calculation second level parameter step 120 according to one or more exemplary embodiments. The calculation second level parameter step 120 generally includes steps 160 to 166, as shown. The order of the steps is shown as a representative example. Other step orders can be implemented to meet the criteria of a specific application.

[0050] In step 160, calculation of the second level parameters may be initiated. In step 162, requested details of the joint parameters of the joint being modeled are received from the user. The requested joint parameters may include, but are not limited to, fastener type, fastener geometry, material type, lamination details, configuration geometry, finite element method (FEM) element details, fastener size details, and mesh type. Other joint parameters may be considered to meet the design criteria of a particular application. In step 164, the second level parameters are calculated using the input parameters 115 provided by the input decision box 116. The calculation may include, but are not limited to:

[0051] Calculation - fastener 2D profile [(x1, y1), (x2, y2), (x3, y3), ... etc.];

[0052] Calculation - laminate layer thickness;

[0053] Calculation - penetration thickness [t1, t2, t3, t4, ... etc.];

[0054] Calculation - Fastener details [e.g., (fastener center, fastener diameter) 1, (fastener center, fastener diameter) 2, (fastener center, fastener diameter) 3, ..., etc.];

[0055] Calculation-Partition Details [Component Sizex , Component size y , X-partition, Y-partition, fastener partition]; and

[0056] Calculation - Component dimensions [length, width, thickness].

[0057] The calculation of the second-stage parameters is concluded in step 166 .

[0058] References Back to References Figure 1A and Figure 1B of Figure 3 , shows a detailed flow chart of an exemplary embodiment of the build component step 124 according to one or more exemplary embodiments. The build component step 124 generally includes steps 180 to 194, as shown. The order of the steps is shown as a representative example. Other step orders can be implemented to meet the criteria of a specific application.

[0059] In step 180, construction of the component operation is initiated. Component parameters are received from the user in step 182 to further define the components that make up the joint being modeled. The component parameters may include, but are not limited to, fastener 2D profiles, laminate layer thicknesses, through thicknesses, fastener details, and partition details. Other component parameters may be considered to meet design criteria for a particular application.

[0060] In step 184, the geometry of the part is built without fasteners. A check is performed in step 186 to determine if the part has fasteners or lacks a fiber-oriented mesh. If fasteners and / or no fiber-oriented mesh are detected, then for each part in the joint (e.g., parts 1 to N), build part step 124 builds the fastener geometry and uses Boolean logic partitioning in subtract step 188 to subtract the fastener from the main part, and then partitions and applies seeds and meshes in step 190. If the part does not have fasteners or has a fiber-oriented mesh, step 192 partitions and applies seeds and meshes. When step 190 or step 192 are completed, the construction of the part ends in step 194.

[0061] References Back to References Figure 1A and Figure 1B of Figure 4 , a detailed flow chart of an exemplary embodiment of updating nodes of the fiber alignment grid step 128 according to one or more exemplary embodiments is shown. The fiber alignment grid step 128 generally includes steps 200 to 210, as shown. The order of steps is shown as a representative example. Other step orders can be implemented to meet the criteria of a specific application.

[0062] The updating of the nodes for fiber alignment of the grid is started in step 200. In step 202, grid parameters are received from a user for a component. The grid parameters may include, but are not limited to, ply orientation, ply grid nodes, and fastener details. Other grid parameters may be implemented to meet the design criteria of a specific application.

[0063] In a rotation step 204, the component node 129 is rotated according to the fiber orientation 203, elements from outside the original component size are removed, and the element type is updated appropriately. A check is performed in decision block 206 to determine whether the component includes a fastener. If the fastener is associated with the component (e.g., there is a hole specified for the fastener), the element at the fastener location is removed, and the element type is updated appropriately. After the element at the fastener location has been removed in step 208, or the fastener is not detected in decision block 206, the node update for the fiber alignment is completed in step 210.

[0064] References Back to References Figure 1A and Figure 1B of Figure 5 , shows a detailed flow chart of an exemplary implementation of the curvature update step 132 according to one or more exemplary implementations. The curvature update step 132 generally includes steps 220 to 228, as shown. The order of the steps is shown as a representative example. Other step orders can be implemented to meet the criteria of a specific application.

[0065] In step 220, the updating of nodes for curvature is started. In step 222, curvature parameters are received from the user for the component. The curvature parameters may include, but are not limited to, component mesh details, configuration details, and curvature details. Other curvature parameters may be implemented to meet the design criteria of a specific application.

[0066] In calculation step 224, a calculation is performed to determine the center of curvature 225 of the joint (or component). Update step 226 is a loop 1 to N times, once for each of the N components. In update step 226, the nodes of the component are updated based on the center of curvature 225 and the actual curvature. In step 228, the nodes of the curvature are updated.

[0067] References Back to References Figure 1A and Figure 1B of Figure 6 , shows a detailed flow chart of an example implementation of the assemble sample step 136 according to one or more exemplary embodiments. The assemble sample step 136 generally includes steps 240 to 254, as shown. The order of the steps is shown as a representative example. Other step orders can be implemented to meet the criteria of a specific application.

[0068] Assembly of the component begins in step 240. In step 242, configuration parameters are received from a user for the component. The configuration parameters may include, but are not limited to, configuration details and mesh component details. Other configuration parameters may be implemented to meet design criteria for a specific application.

[0069] Step 244 is looped, once for each of the N strip-type components. In step 244, as an example, the strip is added and translated / rotated to the joint based on the configuration details of the strip. A check is performed in step 246 to determine whether the joint includes a spacer. If a spacer is detected, then in step 248, as an example, the spacer is added and translated / rotated to the joint based on the configuration details of the spacer. After the spacer has been added in step 248, or after the spacer has not been detected in decision box 246, a check is performed in decision box 250 to determine whether the joint includes a shim. If a shim is detected, then in step 252, as an example, the shim is added and translated / rotated to the joint based on the configuration details of the shim. After the shim has been added in step 252, or after the shim has not been detected in decision box 250, assembly is ended in step 254.

[0070] References Back to References Figure 1A and Figure 1B of Figure 7 , shows a detailed flow chart of an exemplary embodiment of an input parameter selection step 114 for obtaining fastener parameters according to one or more exemplary embodiments. Step 114 generally includes steps 260 to 274, as shown. The order of steps is shown as a representative example. Other step orders can be implemented to meet the criteria of a specific application.

[0071] The acquisition of fastener parameters begins in step 260. In step 262, a fastener selection is received from a user. The fastener selection may include, but is not limited to, a part number and a fastener geometry specified via the graphical user interface function 102. Other types of faster selections may be implemented to meet the design criteria of a particular application.

[0072] In decision block 264, the user input is checked to determine if the fastener selection is for a part number. If the user input is a part number, then the fastener geometry is constructed in step 266 according to the dimensions specified in the part drawing in the fastener library 106b. If the user input is not a part number, then the fastener geometry is constructed in step 268 according to the user input dimensions specified in the GUI 102.

[0073] In the assignment step 270, the fastener part is generated in ABAQUS and the identified materials 271 and segments are assigned. In step 272, a fastener mesh with local refinement is generated. In various embodiments, the fastener mesh creation can conform to best practices. Other types of fastener mesh creation can be implemented to meet the design criteria of a specific application. In step 274, the fastener selection is completed.

[0074] References Back to References Figure 1A and Figure 1B of Figure 8 , shows a detailed flow chart of an exemplary embodiment of an input parameter selection step 114 for obtaining material parameters according to one or more exemplary embodiments. Step 114 generally includes steps 280 to 298, as shown. The order of steps is shown as a representative example. Other step orders can be implemented to meet the criteria of a specific application.

[0075] The acquisition of material parameters begins in step 280. In step 282, a material selection is received from a user. The material selection may include, but is not limited to, a metal selection and a composite material selection. Other material selections may be implemented to meet the design criteria of a specific application.

[0076] In decision box 284, user input is checked to determine whether metal or composite materials are used in modeling the part. If metal is modeled, linear elastic material properties are defined for metal in step 286. Next, a standard material card for metal is created in step 288. If composite materials are modeled, linear elastic orthotropic material properties for composite materials are defined in step 290. A check is performed in decision box 292 to determine whether progressive failure analysis is appropriate for composite materials. If progressive failure analysis is appropriate, a progressive failure theory card specific to the user-defined composite material is created in step 294. If no progressive failure analysis is appropriate, a standard material card for composite materials is created in step 296. Material selection is terminated in step 298.

[0077] References Back to References Figure 1A and Figure 1B of Fig. 9 , shows a schematic block diagram of an exemplary embodiment of a computer-based system 300 according to one or more exemplary embodiments. The system 300 is operable to perform the method 100 for modeling a joint. The system 300 is operable to generate an input file suitable for a finite element analysis (FEA) simulation in a non-transitory computer-readable storage device. The input file defines the joint in software and can be executed by a FEA simulator to verify the correct function and performance of the design.

[0078] The system 300 includes a computer 310 having one or more processors 312 (one is shown) and one or more storage media 314a-314b. A first storage medium (e.g., 314a) may contain one or more instructions 316 (or code or software program) that can be read and executed by the processor 312. In various embodiments, the instructions 316 form a suite of Python scripts. The first storage medium 314a may also record the material library 106a and the fastener library 106b. A storage input file 318 storing data of the input file 145 defining the model of the joint may reside in a second storage medium (e.g., 314b). The first storage medium 314a may be a non-transitory computer-readable storage medium. The second storage medium 314b may be a non-transitory and / or transitory computer-readable storage medium.

[0079] The instructions 316 can be read and executed by the computer 310 (e.g., the processor 312) to implement the process of generating a storage input file 318 for the model 125a-125g of the joint. The material library 106a and the fastener library 106b can be appropriately accessed during execution. In various embodiments, the instructions 316, the material library 106a, the fastener library 106b, and / or the storage input file 318 can be stored in the same storage medium 314a or 314b.

[0080] refer to Fig.10 , shows a schematic plan view and a cross-sectional view of an exemplary joint 340 according to one or more exemplary embodiments. The joint 340 in this example includes a plurality of (e.g., four) strips 342a-342d, a plurality of (e.g., two) washers 344a-344b, and a plurality of (e.g., eight) fastener holes 346a-346h. A plurality of fasteners (one shown) 348 are arranged in the fastener holes 346a-346h. The fastener holes 346a-346h and the corresponding fasteners 348 are arranged in a pattern 350.

[0081] Each strip 342a-342d is defined by material, thickness, length, and width. Similarly, each shim 344a-344b is defined by material, thickness, length, and width. Fastener holes 346a-346h are defined by material diameter, length, and width. Pattern 350 defines the number of columns (NC) (e.g., not greater than 4 in this example), the number of rows (NR) (e.g., not greater than 4 in this example), the x spacing (Sx), and the y spacing (Sy). The border is defined by the edge distance (Ey) and the end spacing (Ex).

[0082] Embodiments of the present disclosure relate to a suite of Python scripts that enable automatic modeling of common bolted joints for analyzing detailed stresses around fastener holes. The system / method is implemented as a plug-in for Abaqus / CAE, which is a commercial software suite for simulation based on finite element analysis. The system / method is designed to handle manufacturing variations such as oversized holes and fasteners and out-of-specification preloads via parametric modeling. The system / method also has a built-in material and fastener library. Therefore, the time and effort for modeling and analysis are reduced, and the accuracy of stress prediction and strain prediction for both static strength and fatigue strength of fracture-sensitive joints is improved. The reduction in time and effort leads to cost savings in reducing model building and analysis time (from days to hours for each detailed model). In addition, the accuracy prediction provided by the system / method avoids unexpected fractures, which may lead to redesign, reprocessing and / or delayed certification and production.

[0083] Various embodiments of the system / method can: (1) be fully parameterized and automated; (2) include commonly used bolted joint configurations: single shear, double shear, universal bearing bypass, and tapered joints; (3) include up to M by M (e.g., 4 by 4) fastener arrays with various pitches and spacings; (4) provide built-in libraries for fasteners and materials; (5) be able to assign variants to individual fasteners and holes; (6) include integrated analysis job submission to a remote computing cluster; and (7) be capable of fiber-oriented meshing for advanced composite progressive failure analysis.

[0084] As explained above and reiterated below, the present disclosure includes, but is not limited to, the following exemplary implementations.

[0085] Clause 1. A method for modeling a joint with fasteners, comprising: receiving multiple input parameters of multiple components connectable to one or more fasteners; calculating multiple second-level parameters based on the multiple input parameters using a computer; constructing multiple component models of the multiple components without one or more fasteners based on the multiple second-level parameters; subtracting multiple fastener holes from the multiple component models; generating an assembly model by combining the multiple component models with one or more fastener models of one or more fasteners in the multiple fastener holes; applying multiple boundary conditions to the assembly model; applying multiple loads to the assembly model under the multiple boundary conditions to generate multiple analysis keywords; and generating an input file based on the multiple analysis keywords, wherein the input file is suitable for finite element analysis.

[0086] Clause 2. The method of clause 1, further comprising rotating a plurality of component nodes of the plurality of component models to align with the optical fiber orientations of the plurality of components.

[0087] Clause 3. The method according to clause 1, further comprising calculating a center of curvature of the assembled model.

[0088] Clause 4. The method of clause 3, further comprising updating a plurality of component nodes of the plurality of component models based on the center of curvature of the assembly model.

[0089] Clause 5. The method of clause 1, further comprising assigning a material to the plurality of part models.

[0090] Clause 6. The method of clause 1, further comprising adding one or more additional models to the assembly model, wherein the one or more additional models include one or more strip models, spacer models, shim models, or a combination thereof.

[0091] Clause 7. The method of clause 6, further comprising translating one or more additional models within the assembled model.

[0092] Clause 8. The method of clause 6, further comprising rotating one or more additional models within the assembled model.

[0093] Clause 9. The method of clause 1, further comprising reading a plurality of input parameters and one or more fasteners from one or more libraries.

[0094] Clause 10. A system for modeling a joint with fasteners, comprising: one or more libraries operable to store multiple input parameters of multiple components and multiple fasteners; and a computer operable to: receive multiple input parameters of multiple components connectable to one or more fasteners from the one or more libraries; calculate multiple second-level parameters based on the multiple input parameters; construct multiple component models of the multiple components without one or more fasteners based on the multiple second-level parameters; subtract multiple fastener holes from the multiple component models; generate an assembly model by combining the multiple component models with one or more fastener models of one or more fasteners in the multiple fastener holes; apply multiple boundary conditions to the assembly model; apply multiple loads to the assembly model under the multiple boundary conditions to generate multiple analysis keywords; generate an input file based on the multiple analysis keywords, wherein the input file is suitable for finite element analysis.

[0095] Clause 11. The system of clause 10, wherein the computer is further operable to rotate a plurality of component nodes of the plurality of component models to align with the optical fiber orientations of the plurality of components.

[0096] Clause 12. The system of clause 10, wherein the computer is further operable to calculate a center of curvature of the assembled model.

[0097] Clause 13. The system of clause 12, wherein the computer is further operable to update a plurality of component nodes of the plurality of component models based on the center of curvature of the assembly model.

[0098] Clause 14. The system of clause 10, wherein the computer is further operable to assign materials to the plurality of part models.

[0099] Clause 15. The system of clause 10, wherein the computer is further operable to add one or more additional models to the assembly model, wherein the one or more additional models include one or more strip models, spacer models, shim models, or a combination thereof.

[0100] Clause 16. The system of clause 15, wherein the computer is further operable to translate one or more additional models within the assembled model.

[0101] Clause 17. The system of clause 15, wherein the computer is further operable to rotate one or more additional models within the assembled model.

[0102] Clause 18. A non-transitory computer-readable storage medium storing instructions for controlling data processing, which instructions, when executed by a processor, cause the processor to perform multiple operations, the multiple operations comprising: receiving multiple input parameters of multiple components connectable to one or more fasteners; calculating multiple second-level parameters based on the multiple input parameters; constructing multiple component models of the multiple components without one or more fasteners based on the multiple second-level parameters; subtracting multiple fastener holes from the multiple component models; generating an assembly model by combining the multiple component models with one or more fastener models of one or more fasteners in the multiple fastener holes; applying multiple boundary conditions to the assembly model; applying multiple loads to the assembly model under the multiple boundary conditions to generate multiple analysis keywords; and generating an input file based on the multiple analysis keywords, wherein the input file is suitable for finite element analysis.

[0103] Clause 19. The non-transitory computer-readable storage medium of Clause 18, wherein the plurality of operations further comprises rotating a plurality of component nodes of the plurality of component models to align with optical fiber orientations of the plurality of components.

[0104] Clause 20. The non-transitory computer-readable storage medium of clause 18, wherein the plurality of operations further comprises calculating a center of curvature of the assembly model; and updating a plurality of component nodes of the plurality of component models based on the center of curvature of the assembly model.

[0105] The present disclosure is susceptible to implementation in many different forms. Representative embodiments of the present disclosure are shown in the drawings and described in detail herein, with the understanding that these embodiments are provided as illustrations of the disclosed principles rather than limitations on the broad aspects of the present disclosure. In this regard, elements and limitations such as those described in the abstract, background, summary, and detailed description sections but not explicitly set forth in the claims should not be incorporated into the claims individually or collectively by implication, inference, or otherwise.

[0106] For the purpose of this detailed description, unless specifically denied, the singular includes the plural, and vice versa. The words "and" and "or" shall be both conjunctive and disjunctive. The words "any" and "all" shall both mean "any and all", and the words "including", "containing", "comprising", "having", etc. shall each mean "including but not limited to". In addition, approximate words such as "about", "almost", "substantially", "approximately" and "generally" may be used herein in the sense of "at, near, or nearly at", or "within 0%-5% of", or "within acceptable manufacturing tolerances", or other logical combinations thereof. With reference to the accompanying drawings, the same reference numerals in the drawings refer to the same parts.

[0107] The detailed description and the accompanying drawings or figures support and describe the present disclosure, but the scope of the present disclosure is limited only by the claims. Although some of the best modes and other embodiments for implementing the claimed disclosure have been described in detail, there are various alternative designs and embodiments for practicing the present disclosure defined in the appended claims. In addition, the embodiments shown in the drawings or the features of the various embodiments mentioned in this specification do not have to be understood as embodiments independent of each other. On the contrary, it is possible that each feature described in one example of an embodiment can be combined with one or more other desired features from other embodiments, resulting in other embodiments not being described in words or by reference to the drawings. Therefore, such other embodiments fall within the framework of the scope of the appended claims.

Claims

1. A method for modeling a joint having a fastener, comprising: receiving a plurality of input parameters of a plurality of components connectable with one or more fasteners; calculating, using a computer, a plurality of second level parameters based on the plurality of input parameters; constructing a plurality of component models of the plurality of components without the one or more fasteners based on the plurality of second level parameters; subtracting a plurality of fastener holes from the plurality of component models; generating an assembly model by combining the plurality of component models with one or more fastener models of the one or more fasteners in the plurality of fastener holes; applying a plurality of boundary conditions to the assembly model; applying a plurality of loads to the assembly model under the plurality of boundary conditions to generate a plurality of analysis keywords; as well as An input file is generated based on the plurality of analysis keywords, wherein the input file is suitable for finite element analysis.

2. The method according to claim 1, further comprising: A plurality of component nodes of the plurality of component models are rotated to align with the optical fiber orientations of the plurality of components.

3. The method according to claim 1, further comprising: The center of curvature of the assembled model is calculated.

4. The method according to claim 3, further comprising: A plurality of component nodes of the plurality of component models are updated based on the center of curvature of the assembly model.

5. The method according to claim 1, further comprising: Materials are assigned to the plurality of part models.

6. The method according to claim 1, further comprising: One or more additional models are added to the assembly model, wherein the one or more additional models include one or more strip models, spacer models, shim models, or a combination thereof.

7. The method according to claim 6, further comprising: The one or more additional models are translated within the assembled model.

8. The method according to claim 6, further comprising: The one or more additional models are rotated within the assembled model.

9. The method according to claim 1, further comprising: The plurality of input parameters and the one or more fasteners are read from one or more libraries.

10. A system for modeling a joint having a fastener, comprising: one or more libraries operable to store a plurality of input parameters for a plurality of components and a plurality of fasteners; as well as A computer capable of operating: receiving, from the one or more libraries, the plurality of input parameters of the plurality of components connectable with one or more fasteners; calculating a plurality of second level parameters based on the plurality of input parameters; constructing a plurality of component models of the plurality of components without the one or more fasteners based on the plurality of second level parameters; subtracting a plurality of fastener holes from the plurality of component models; generating an assembly model by combining the plurality of component models with one or more fastener models of the one or more fasteners in the plurality of fastener holes; applying a plurality of boundary conditions to the assembly model; applying a plurality of loads to the assembly model under the plurality of boundary conditions to generate a plurality of analysis keywords; as well as An input file is generated based on the plurality of analysis keywords, wherein the input file is suitable for finite element analysis.

11. The system according to claim 10, wherein: The computer is further operable to: A plurality of component nodes of the plurality of component models are rotated to align with the optical fiber orientations of the plurality of components.

12. The system according to claim 10, wherein: The computer is further operable to: The center of curvature of the assembled model is calculated.

13. The system according to claim 12, wherein: The computer is further operable to: A plurality of component nodes of the plurality of component models are updated based on the center of curvature of the assembly model.

14. The system according to claim 10, wherein: The computer is further operable to: Materials are assigned to the plurality of part models.

15. The system according to claim 10, wherein: The computer is further operable to: One or more additional models are added to the assembly model, wherein the one or more additional models include one or more strip models, spacer models, shim models, or a combination thereof.

16. The system of claim 15, wherein: The computer is further operable to: The one or more additional models are translated within the assembled model.

17. The system of claim 15, wherein: The computer is further operable to: The one or more additional models are rotated within the assembled model.

18. A non-transitory computer-readable storage medium storing instructions for controlling data processing, the instructions, when executed by a processor, causing the processor to perform a plurality of operations, the plurality of operations comprising: receiving a plurality of input parameters of a plurality of components connectable with one or more fasteners; calculating a plurality of second level parameters based on the plurality of input parameters; constructing a plurality of component models of the plurality of components without the one or more fasteners based on the plurality of second level parameters; subtracting a plurality of fastener holes from the plurality of component models; generating an assembly model by combining the plurality of component models with one or more fastener models of the one or more fasteners in the plurality of fastener holes; applying a plurality of boundary conditions to the assembly model; applying a plurality of loads to the assembly model under the plurality of boundary conditions to generate a plurality of analysis keywords; as well as An input file is generated based on the plurality of analysis keywords, wherein the input file is suitable for finite element analysis.

19. The non-transitory computer-readable storage medium of claim 18, wherein: The plurality of operations also include: A plurality of component nodes of the plurality of component models are rotated to align with the optical fiber orientations of the plurality of components.

20. The non-transitory computer-readable storage medium of claim 18, wherein: The plurality of operations also include: calculating the center of curvature of the assembled model; and A plurality of component nodes of the plurality of component models are updated based on the center of curvature of the assembly model.

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