Modeling joints with fasteners
Patent Information
- Application Number
- JP2024133710
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-08-24
- Filing Date
- 2024-08-09
- Publication Date
- 2025-03-07
Smart Images
Figure 2025031606000001 
Figure 2025031606000002 
Figure 2025031606000003
Abstract
Description
[Technical field]
[0001]
[0001] The present disclosure relates generally to modeling components, and more particularly to modeling joints using fasteners. [Background technology]
[0002]
[0002] The primary cause of cracks found during full-scale fatigue testing is unexplained local stresses and strains. Changing designs or molds to solve problems during the certification process is costly and causes program delays. Existing modeling solutions are either manual or have low enough fidelity in terms of their ability to capture three-dimensional contact interactions between fasteners and structural details. Manual model building processes also do not allow for timely assessment of all manufacturing variability.
[0003]
[0003] Accordingly, those skilled in the art continue to conduct research and development efforts in the area of modeling the joints of two or more components with one or more fasteners to improve stress predictions at the fastener locations to reduce risk and to do so within program schedules. Summary of the Invention
[0004]
[0004] A method for modeling a joint using a fastener is provided herein. The method includes receiving a plurality of input parameters of a plurality of components that can be joined with one or more fasteners, calculating a plurality of second level parameters on a computer based on the plurality of input parameters, constructing a plurality of component models of the plurality of components lacking one or more fasteners based on the plurality of second level parameters, subtracting a plurality of fastener bores 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 bores, applying a plurality of boundary conditions to the assembly model, applying a plurality of loads 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 component nodes of the component models to align with fiber directions of the components.
[0006] In one or more embodiments, the method further includes calculating a center of curvature of the assembly 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 and the curvature of the assembly model.
[0008] In one or more embodiments, the method further includes assigning materials to the plurality of component models.
[0009]
[0009] In one or more embodiments, the method further includes adding one or more additional models to the assembly model, The one or more additional models include one or more strap models, spacer models, shim models, or combinations thereof.
[0010] In one or more embodiments, the method further includes translating one or more additional models within the assembly model.
[0011] In one or more embodiments, the method further includes rotating one or more additional models within the assembly model.
[0012] In one or more embodiments, the method further includes reading the plurality of input parameters and the one or more fasteners from one or more libraries.
[0013]
[0013] A system for modeling a joint using a fastener is provided herein. The system includes one or more libraries operable to store a plurality of input parameters of a plurality of components and a plurality of fasteners, and a computer. The computer is operable to perform the following: receive a plurality of input parameters of a plurality of components that can be joined with one or more fasteners from one or more libraries; calculate a plurality of second level parameters based on the plurality of input parameters; build a plurality of component models of the plurality of components lacking one or more fasteners based on the plurality of second level parameters; subtract a plurality of fastener bores from the plurality of component models; generate 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 bores; apply a plurality of boundary conditions to the assembly model; apply a plurality of loads under the plurality of boundary conditions to the assembly model to generate a plurality of analysis keywords; and generate an input file based on the plurality of analysis keywords. The input file is suitable for finite element analysis.
[0014]
[0014] In one or more embodiments of the system, the computer is further operable to rotate component nodes of the component models to align with fiber directions of the components.
[0015] In one or more embodiments of the system, the computer is further operable to calculate a center of curvature of the assembly model.
[0016] In one or more embodiments of the system, the computer is further operable to update the component nodes of the component models based on the center and the 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 component 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 including one or more strap models, spacer models, shim models, or combinations thereof.
[0019] In one or more embodiments of the system, the computer is further operable to translate one or more additional models within the assembly model.
[0020] In one or more embodiments of the system, the computer is operable to rotate one or more additional models within the assembly model.
[0021]
[0021] A non-transitory computer-readable storage medium is provided herein having instructions for controlling data processing. When executed by a processor, the instructions cause the processor to perform a number of operations including receiving a number of input parameters of a number of components that can be joined with one or more fasteners, calculating a number of second level parameters based on the number of input parameters, constructing a number of component models of a number of components lacking one or more fasteners based on the number of second level parameters, subtracting a number of fastener bores from the number of component models, generating an assembly model by combining the number of component models with one or more fastener models of one or more fasteners in the number of fastener bores, applying a number of boundary conditions to the assembly model, applying a number of loads under the number of boundary conditions to the assembly model to generate a number of analysis keywords, and generating an input file based on the number of analysis keywords. The input file is suitable for finite element analysis.
[0022]
[0022] In one or more embodiments of the non-transitory computer-readable storage medium, the operations further include rotating component nodes of the component models to align with fiber directions of the components.
[0023]
[0023] In one or more embodiments of the non-transitory computer-readable storage medium, the operations further include calculating a center of curvature of the assembly model and updating a plurality of component nodes of a plurality of component models based on the center and curvature of the assembly model.
[0024]
[0024] The above features and advantages of the present disclosure, as well as other features and advantages, will become readily apparent from the following detailed description of the best mode for carrying out the disclosure when considered in conjunction with the accompanying drawings. [Brief description of the drawings]
[0025] [Figure 1A]1A-1B are flow diagrams of a method of plug-in modeling code operation in accordance with one or more exemplary embodiments. [Figure 1B] 1A-1B are flow diagrams of a method of plug-in modeling code operation in accordance with one or more exemplary embodiments. [Diagram 2]
[0026] FIG. 11 is a detailed flow diagram for calculating second-level parameters in accordance with one or more exemplary embodiments. [Diagram 3]
[0027] FIG. 1 is a detailed flow diagram for building components in accordance with one or more exemplary embodiments. [Figure 4]
[0028] FIG. 11 is a detailed flow diagram for updating nodes for a fiber aligned mesh in accordance with one or more exemplary embodiments. [Diagram 5]
[0029] FIG. 13 is a detailed flow diagram for curvature, in accordance with one or more exemplary embodiments. [Figure 6]
[0030] FIG. 10 is a detailed flow diagram for assembling components in accordance with one or more exemplary embodiments. [Figure 7]
[0031] FIG. 11 is a detailed flow diagram for obtaining fastener parameters in accordance with one or more exemplary embodiments. [Figure 8]
[0032] FIG. 13 is a detailed flow diagram for obtaining material parameters in accordance with one or more exemplary embodiments. [Figure 9]
[0033] FIG. 1 is a schematic block diagram of a computer-based system in accordance with one or more exemplary embodiments. [Figure 10]
[0034] 3A-3C are schematic plan and cross-sectional views of a joint 340 according to one or more exemplary embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026]
[0035] Various embodiments of the present disclosure provide methods and / or systems for modeling fastener-based joints, the method including receiving input parameters of components connectable with one or more fasteners, calculating second level parameters based on the input parameters, and constructing a plurality of component models of the plurality of components lacking the fasteners based on the second level parameters, the method further including subtracting a plurality of fastener bores from the plurality of component models, combining the plurality of component models with a plurality of fastener models of the plurality of fasteners within the plurality of fastener bores to generate an assembly model, and applying a plurality of boundary conditions to the assembly model. The method also includes applying a plurality of loads to the assembly model and generating an input file suitable for finite element analysis based on a response of the assembly model to the plurality of loads and the boundary conditions.
[0027]
[0036] In some embodiments, the method may include rotating component nodes of the component models to align with a fiber direction of the components, calculating a center of curvature of the assembly model, and updating the component nodes of the component models based on the center and curvature of the assembly model. If specified for the joint design, the method may include adding one or more additional models to the assembly model. The multiple additional models generally include one or more strap models, spacer models, shim models, or combinations thereof. The multiple additional models may be translated and / or rotated within the assembly model. The system generally includes a computer and one or more libraries. The one or more libraries store input parameters of the components and fasteners. The computer is operable to receive input parameters of the components connectable with the one or more fasteners from the library, calculate second level parameters based on the input parameters, and build component models of the components lacking the fasteners based on the second level parameters. The computer is also operable to subtract the fastener bores from the component models, combine the component models with fastener models of the fasteners in the fastener bores (or holes) to generate an assembly model, apply boundary conditions to the assembly model, and apply loads to the assembly model. The computer is also operable to generate an input file suitable for finite element analysis based on the response of the assembly model to the loads and boundary conditions. The system has been shown to be capable of automating high fidelity, physics-based, three-dimensional finite element analysis models, providing accurate stresses and accessing the effects of manufacturing variations to further reduce risk.
[0028]
[0037] 1A-1B, a flow diagram of an exemplary method of operation for modeling plug-in code is shown, in accordance with one or more exemplary embodiments. The method (or process) 100 may be implemented by one or more computers and one or more user interface devices (e.g., a monitor with a keyboard and / or mouse). The method 100 generally includes steps 102 through 156, as shown. The sequence of steps is shown as a representative example. Other orders of steps may be implemented to meet the criteria of a particular application.
[0029]
[0038] In various embodiments, the functionality provided by the method 100 is distributed between a graphical user interface (GUI) functionality 102 and a kernel functionality 104. The GUI functionality 102 includes access to materials library 106a, access to fasteners library 106b, a start step 110, a build material / read step 112, an input parameter selection step 114, an input decision block 116, a submit for analysis decision block 150, a job submission step 152, a job status acquisition step 154, and an end step 156.
[0030]
[0039] The kernel function 104 includes a second level parameter calculation step 120 and a loop step 122. The loop step 122 includes a component construction step 124, a fiber orientation determination block 126, a node update for fiber aligned mesh step 128, a curvature determination block 130, a curvature update step 132, and a material assignment step 134. The kernel function 104 further includes a coupon assembly step 136, a boundary condition application step 138, a load application step 140, a first input file write step 142, a solver determination block 144, a format conversion step 146, and a second input file write step 148. The second level parameter calculation step 120 receives input parameters 115 from the input determination block 116 in a receiving step 119. The solver determination block 144 and the second input file write step 148 submit the input file 145 to a submit for analysis determination block 150.
[0031]
[0040] The GUI functionality 102 implements user input selection and job status functionality. The GUI functionality 102 is operable to provide a mechanism for a user to select the various (e.g., N) components used to model the joint, as well as the number, type, and placement of fasteners used to hold the joint together. The GUI functionality 102 is also operable to provide a mechanism for a user to determine which jobs are submitted for analysis, as well as the status of such jobs running on one or more remote server computers and / or one or more local server computers.
[0032]
[0041] The kernel function 104 implements a modeling tool that is used to generate one of two types of input files that model the joint. In various embodiments, the first type of input file may be an Abaqus / CAE (Complete Abaqus Environment) input file. Abaqus / CAE is a software application used for both modeling and analyzing (pre-processing) mechanical parts and assemblies and for visualizing finite element analysis results. Abaqus / CAE is developed by and available from Dassault Systems, Velizy-Villacoublay, France. In various embodiments, the second type of input file may be an LS-Dyna format input file. LS-Dyna is a general purpose multi-physics simulation software package. LS-Dyna is developed by and available from Ansys, Inc., Canonsburg, Pennsylvania. In various embodiments, the input file may present the model as a finite element model. In some embodiments, the input file may present the model as a geometric model.
[0033]
[0042] The material library 106a implements a database of materials suitable for use in manufacturing the joints. The material data in the material library 106a may include, without limitation, common homogeneous isotropic materials (e.g., metals) and custom user materials, elastic and progressive failure parameters for composite plies, material models for progressive failure analysis (e.g., extensible to Hashin, Helius, and others), and adhesive materials. Other types of material parameters may be included to meet the design criteria of a particular application.
[0034]
[0043] The fastener library 106a implements a database of fasteners suitable for use in manufacturing a joint. The fastener data in the fastener library 106b may include, without limitation, protruding head fasteners, countersink fasteners, bolts, and nuts. Other types of fastener parameters may be included to meet the design criteria of a particular application.
[0035]
[0044] At step 110, the method 100 begins by collecting (or reading) build materials at step 112 based on a joint design provided by a user. The build materials / reading step 112 is operable to assemble materials used to model the joint based on the user-supplied design. The build materials / reading step 112 defines the parts, material types, spacers, thickness, length, width, fasteners, number and placement of holes, pattern, and boundaries for the joint model. Fastener parameters from the fastener library 106b are added to the build material parameters at input parameter selection step 114. The input parameter selection step 114 is operable to buffer the material parameters and fastener parameters selected by the user.
[0036]
[0045] A check is then made at input decision block 116. If there are not enough parameters buffered at input parameter selection step 114, method 100 returns to input parameter selection step 114 to collect the missing parameters. If suitable parameters are present, the method proceeds to kernel function 104 (e.g., second level parameter calculation step 120) and via the Yes branch of input decision block 116, input parameters 115 are received by second level parameter calculation step 120.
[0037]
[0046] The second level parameter calculation step 120 is operable to generate second level parameters 121 from the input parameters received from the GUI functionality 102. Step 122 loops through a component construction step 124 to a material allocation step 134 for the various components in the design configuration of the joint being modeled. The component construction step 124 generates an initial version of the component models 125a (e.g., coupon model 125b, fastener model 125c, add model 125d, strap model 125e, spacer model 125f, and shim model 125g) based on the input parameter selection step 114 and the second level parameters 121. A check is made in a fiber direction determination block 126 to determine whether the component contains a mesh with a particular fiber direction. If the particular direction is detected, the nodes of the component are updated for fiber alignment with the mesh in step 128. Thereafter, or if the particular direction is not detected, another check is made in a curvature determination block 130 for the curvature of the component. If curvature is detected, the loop step 122 proceeds to a curvature update step 132. In the curvature update step 132, the nodes of the models 125a-125g are updated to account for the curvature. After the nodes have been updated for curvature, or if curvature was not detected, materials for the components are assigned in a material allocation step 134. The loop step 122 loops to the component construction step 124 for each component in the joint. Upon completion, the method 100 proceeds to a coupon assembly step 136.
[0038]
[0047] In a coupon assembly step 136, once the component models 125a-125g have been constructed and possibly updated, they are assembled into a coupon to form an assembly model 125h of the joint. In a boundary condition application step 138, boundary conditions 139 are applied to the assembly model 125h. In a load application step 140, one or more loads 141 are applied to the assembly model 125h under the boundary conditions 139 to generate analysis keywords 143. The analysis keywords 143 are captured in a first input file format (e.g., Abaqus / CAE format). The resulting data is written (or generated) to an input file 145 by a first input file writing step 142. A check is made in a solver decision block 144 to determine whether the format of the input file 145 written / generated in the first input file writing step 142 can be converted to another input file format. If the format of input file 145 is to be converted, input file 145 is converted from the first input file format to a second input file format (e.g., LS-Dyna format) in a format conversion step 146. Then, in a write second input file step 148, the data in the second input file format is written (or generated) to input file 145 (e.g., in LS-Dyna format).
[0039]
[0048] An input file 145 in a first input file format (e.g., written in a first input file step 142 and determined not to be converted in a solver determination block 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 determination block 150. If the input file is determined to be submitted for analysis (e.g., a physics-based three-dimensional finite element analysis) in the submit for analysis determination block 150, the input file is submitted in a submit step 152 to one or more computers running Abaqus / CAE or LS-Dyna simulation software. During the simulation, a get job status step 154 may provide feedback to the user regarding the ongoing results of the simulation. After the simulation is completed or if the simulation was not started in the submit for analysis determination block 150, the method 100 ends in an end step 156.
[0040]
[0049] 2, and with reference back to FIG. 1A and FIG. 1B, a detailed flow diagram of an exemplary implementation of the second level parameter calculation step 120, in accordance with one or more exemplary embodiments, is shown. The second level parameter calculation step 120 generally includes steps 160 through 166 as shown. The sequence of steps is shown as a representative example. Other step orders may be implemented to meet the criteria of a particular application.
[0041]
[0050] In step 160, the calculation of second level parameters may begin. In step 162, requested details of the joint parameters for which the joint is to be modeled are received from the user. The requested joint parameters may include, but are not limited to, fastener type, fastener shape parameters, material type, layer details, construction geometric parameters, Finite Element Method (FEM) element details, fastener oversize details, and mesh type. Other joint parameters may be considered to meet the design criteria of the particular application. In step 164, the second level parameters are calculated using the input parameters 115 provided by the input decision block 116. The calculation may include, but is not limited to, the following:
[0042]
[0051] Calculate the two-dimensional profile of the fastener [(x1,y1),(x2,y2),(x3,y3)…etc.].
[0043]
[0052] Calculate the film stack thickness.
[0044]
[0053] Calculate the penetration thickness [t1, t2, t3, t4…etc].
[0045]
[0054] Calculate fastener details [e.g. (fastener center, fastener diameter)1, (fastener center, fastener diameter)2, (fastener center, fastener diameter)3, etc.].
[0046]
[0055] Partition Details [Element Size x , element size y , X-partition, Y-partition, fastener partition] are calculated.
[0047]
[0056] Calculate the dimensions [length, width, thickness] of components.
[0048]
[0057] In step 166, the calculation of the second level parameters is completed.
[0049]
[0058] 3, and with reference back to FIGURE 1A and FIGURE 1B, a detailed flow diagram of one exemplary implementation of component construction step 124 is shown, in accordance with one or more exemplary embodiments. Component construction step 124 generally includes steps 180 through 194 as shown. The sequence of steps is shown as a representative example. Other order of steps may be implemented to meet the criteria of a particular application.
[0050]
[0059] In step 180, the operation of building a component begins. To further define the components that make up the joint to be modeled, component parameters are received from a user in step 182. The component parameters may include, but are not limited to, fastener two-dimensional profile, laminate film thickness, penetration thickness, fastener details, and partition details. Other component parameters may be considered to meet the design criteria of a particular application.
[0051]
[0060] In step 184, the component geometry is constructed without fasteners. A check is made in step 186 to determine if the component has fasteners or lacks a fiber-oriented mesh. If fasteners are detected and / or no fiber-oriented mesh is detected, then for each component in the joint (e.g., components 1 through N), the component construction step 124 constructs the fastener geometry and subtracts the fasteners from the primary component in a subtraction step 188 using Boolean logic division, followed by splitting and applying seeds and meshes in step 190. If the component does not have fasteners or has a fiber-oriented mesh, step 192 splits and applies seeds and meshes. Once step 190 or step 192 is completed, the component construction ends in step 194.
[0052]
[0061] 4, and with reference back to FIG. 1A and FIG. 1B, a detailed flow diagram of the node update step 128 for a fiber aligned mesh is shown, in accordance with one or more exemplary embodiments. The node update step 128 for a fiber aligned mesh generally includes steps 200 to 210 as shown. The sequence of steps is shown as a representative example. Other order of steps may be implemented to meet the criteria of a particular application.
[0053]
[0062] Updating nodes for a fiber aligned mesh begins at step 200. At step 202, mesh parameters for a component are received from a user. The mesh parameters may include, but are not limited to, membrane orientation, membrane mesh nodes, and fastener details. Other mesh parameters may be considered to meet the design criteria of a particular application.
[0054]
[0063] In a rotate step 204, the component nodes 129 are rotated according to the fiber direction 203, elements that fall outside the original component dimensions are removed, and the element type is updated appropriately. A check is made in decision block 206 to determine if the component contains a fastener. If a fastener is associated with the component (e.g., there is a bore specified for a fastener), elements at the fastener location are removed and the element type is updated appropriately. After elements at the fastener location are removed in step 208, or if no fasteners were detected in decision block 206, the updating of fiber-aligned nodes ends in step 210.
[0055]
[0064] 5, and with reference back to FIGURE 1A and FIGURE 1B, a detailed flow diagram of one exemplary implementation of the curvature update step 132, in accordance with one or more exemplary embodiments, is shown. The curvature update step 132 generally includes steps 220 through 228 as shown. The sequence of steps is shown as a representative example. Other orders of steps may be implemented to meet the criteria of a particular application.
[0056]
[0065] Updating the nodes for curvature begins at step 220. At step 222, curvature parameters for the component are received from a user. The curvature parameters may include, but are not limited to, mesh details, construction details, and curvature details of the component. Other curvature parameters may be considered to meet the design criteria of a particular application.
[0057]
[0066] A calculation is performed in calculation step 224 to determine the center of curvature 225 of the joint (or assembly). An update step 226 loops 1 to N times, once for each of the N components. In update step 226, the nodes of the components are updated based on the center of curvature 225 and the actual curvature. The updating of the nodes for the curvature is completed in step 228.
[0058]
[0067] 6, and with reference back to FIGS. 1A and 1B, a detailed flow diagram of one exemplary implementation of coupon assembly step 136 is shown, in accordance with one or more exemplary embodiments. Coupon assembly step 136 generally includes steps 240 through 254 as shown. The sequence of steps is shown as a representative example. Other orders of steps may be implemented to meet the criteria of a particular application.
[0059]
[0068] Component assembly begins at step 240. At step 242, configuration parameters for the component are received from a user. The configuration parameters may include, but are not limited to, configuration details and meshed component details. Other configuration parameters may be considered to meet the design criteria of a particular application.
[0060]
[0069] Step 244 is looped once for each of the N strap type components. In some cases, in step 244, a strap is added to the junction and translated / rotated according to the configuration details for the strap. A check is made in step 246 to determine if the junction includes a spacer. If a spacer is detected, in some cases, in step 248, a spacer is added to the junction and translated / rotated according to the configuration details for the spacer. After a spacer is added in step 248, or if a spacer is not detected in decision block 246, a check is made in decision block 250 to determine if the junction includes a shim. In some cases, in step 252, a shim is added to the junction and translated / rotated according to the configuration details for the shim. After a shim is added in step 252, or if a shim is not detected in decision block 250, assembly ends in step 254.
[0061]
[0070] 7, and with reference back to FIGS. 1A and 1B, a detailed flow diagram of one exemplary implementation of input parameter selection step 114 for obtaining fastener parameters is shown, in accordance with one or more exemplary embodiments. Step 114 generally includes steps 260 through 274 as shown. The sequence of steps is shown as a representative example. Other order of steps may be implemented to meet the criteria of a particular application.
[0062]
[0071] Obtaining fastener parameters begins at step 260. At step 262, a fastener selection is received from a user. The fastener selection may include, but is not limited to, a part number and fastener geometry specified via the graphical user interface functionality 102. Other types of fastener selections may be included to meet the design criteria of a particular application.
[0063]
[0072] At decision block 264, the user input is examined to determine if the selection of the fastener is by part number. If the user input is a part number, the fastener geometry dimensions are constructed in step 266 according to the dimensions shown on the part drawing in fastener library 106b. If the user input is not a part number, the fastener geometry dimensions are constructed in step 268 according to the user input dimensions specified in GUI 102.
[0064]
[0073] In an assignment step 270, the fastener parts are generated in ABAQUS and assigned the identified materials 271 and sections. In step 272, a locally refined fastener mesh is generated. In various embodiments, the generation of the fastener mesh may conform to best practices. The generation of other types of fastener meshes may be included to meet the design criteria of a particular application. The selection of fasteners is completed in step 274.
[0065]
[0074] 8, and with reference back to FIG. 1A and FIG. 1B, a detailed flow diagram of an exemplary implementation of input parameter selection step 114 for obtaining material parameters, according to one or more exemplary embodiments, is shown. Step 114 generally includes steps 280 through 298 as shown. The sequence of steps is shown as a representative example. Other order of steps may be implemented to meet the criteria of a particular application.
[0066]
[0075] Obtaining material parameters begins at step 280. At 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 selection. Other material selections may be implemented to meet the design criteria of a particular application.
[0067]
[0076] At decision block 284, user input is examined to determine if a metal or composite is used in modeling the component. If a metal is modeled, linear elastic material properties for the metal are defined at step 286. A standard material card for the metal is then generated at step 288. If a composite is modeled, linear elastic orthogonal material properties for the composite are defined at step 290. A check is made at decision block 292 to determine if progressive failure analysis is appropriate for the composite material. If progressive failure analysis is appropriate, a progressive failure theory card specific to the user defined composite material is generated at step 294. If progressive failure analysis is not appropriate, a standard material card for the composite material is generated at step 296. Material selection is completed at step 298.
[0068]
[0077] 9, and with reference back to FIGS. 1A and 1B, a detailed flow diagram of an exemplary implementation of a computer-based system 300 is shown in accordance with one or more exemplary embodiments. The system 300 is operable to execute the method 100 for modeling a joint. The system 300 is operable to generate input files in non-transient computer readable storage suitable for a Finite Element Analysis (FEM) simulation. The input files define the joint in software and may be implemented by an FEA simulator to verify proper function and performance of the design.
[0069]
[0078] The system 300 includes a computer 310 having one or more processors 312 (one shown) and one or more storage media 314a-b. A first storage medium (e.g., 314a) may include one or more instructions 316 readable and executable by the processor 312. In various embodiments, the instructions 316 generate a series of Python scripts. The first storage medium 314a may also store a materials library 106a and a fastener library 106b. A storage input file 318 that stores data for an input file 145 that defines a model of a joint may reside in a second storage medium (e.g., 314b). The first storage medium 314a may be a non-transient computer readable storage medium. The second storage medium medium 314b may be a non-transient and / or transient computer readable storage medium.
[0070]
[0079] The instructions 316 may be read and executed by the computer 310 (e.g., the processor 312) to perform a process to generate storage input files 318 for the models of the joints 125a-125g. The materials library 106a and fastener library 106b may be accessed as appropriate during execution. In various embodiments, the instructions 316, the materials library 106a, the fastener library 106b, and / or the storage input files 318 may be stored within the same storage medium 314a or 314b.
[0071]
[0080] 10, a schematic diagram of a top view and cross-section of an example joint 340 is shown in accordance with one or more example embodiments. In one embodiment, joint 340 includes a plurality of (e.g., four) straps 342a-342d, a plurality of (e.g., two) shims 344a-344b, and a plurality of (e.g., eight) fastener bores 346a-346h. A plurality of fasteners (one shown) 348 are disposed within fastener bores 346a-346h. Fastener bores 346a-346h and respective fasteners 348 are arranged in a pattern 350.
[0072]
[0081] Each strap 342a-342d is defined by a material, a thickness, a length, and a width. Similarly, each shim 344a-344b is defined by a material, a thickness, a length, and a width. Fastener bores 346a-346h are defined by a material, a diameter, a length, and a width. Pattern 350 is defined by a number of columns (NC) (e.g., four or less in one embodiment), a number of rows (NR) (e.g., four or less in one embodiment), an x-spacing (S x ), and y-spacing (S y The boundary defines the edge distance (E y ) and end spacing (E x ) is defined by
[0073]
[0082] Embodiments of the present disclosure are directed to a set of Python scripts that enable automated modeling of a typical bolted joint for detailed stress analysis around the fastener bore. The system / method is implemented as a plug-in to Abaqus / CAE, a commercially available software suite for finite element analysis-based simulation. The system / method is designed to accommodate manufacturing variations such as oversized bores and fasteners and non-standard preloading through parametric modeling. The system / method also incorporates a library of materials and fasteners. Thus, modeling and analysis time and effort are reduced, improving the accuracy of stress and strain predictions for both static and fatigue strength of fracture-sensitive joints. The reduction in time and effort results in cost savings by reducing model building and analysis time for each detailed model from days to hours. Furthermore, the accurate predictions provided by the system / method avoid surprises from unexpected cracks that may lead to redesigns, tooling changes, and / or certification and production delays.
[0074]
[0083] Various embodiments of the system / method are: (1) fully parametric and automated, (2) include commonly used bolted joint configurations, single shear, double shear, universal bearing bypass, and tapered joints, (3) include fastener arrays up to MxM (e.g., 4x4) with various pitches and spacings, (4) provide built-in fastener and material libraries, (5) allow for individual fastener and bore variations, (6) include integrated analysis job submission to remote compute clusters, and (7) allow fiber oriented mesh generation for advanced composite progressive failure analysis.
[0075]
[0084] As noted above and reiterated below, the present disclosure includes, without limitation, the following exemplary embodiments.
[0076]
[0085] Article 1. 1. A method for modeling a fastener joint, the method comprising: receiving input parameters of a plurality of components joinable with one or more fasteners; calculating on a computer a plurality of second level parameters based on the input parameters; constructing a plurality of component models of the plurality of components lacking the one or more fasteners based on the plurality of second level parameters; subtracting a plurality of fastener bores from the plurality of component models; combining the plurality of component models with one or more fastener models of the one or more fasteners in the plurality of fastener bores to generate an assembly model; 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 suitable for finite element analysis based on the plurality of analysis keywords.
[0077]
[0086] Article 2. 13. The method of claim 1, further comprising rotating component nodes of the component models to align with fiber directions of the components.
[0078]
[0087] Article 3. 13. The method of claim 1, further comprising calculating a center of curvature of the assembly model.
[0079]
[0088] Article 4. 4. The method of claim 3, further comprising updating component nodes of the component models based on the centroid and the curvature of the assembly model.
[0080]
[0089] Article 5. 13. The method of claim 1, further comprising assigning materials to the plurality of component models.
[0081]
[0090] Article 6. 13. The method of claim 1, further comprising adding one or more additional models to the assembly model, the one or more additional models comprising one or more strap models, spacer models, shim models, or combinations thereof.
[0082]
[0091] Article 7. 7. The method of claim 6, further comprising translating the one or more additional models within the assembly model.
[0083]
[0092] Article 8. 7. The method of claim 6, further comprising rotating the one or more additional models within the assembly model.
[0084]
[0093] Article 9. 13. The method of claim 1, further comprising reading the plurality of input parameters and the one or more fasteners from one or more libraries.
[0085]
[0094] Article 10. 13. A system for modeling fastener joints comprising: one or more libraries operable to store input parameters of a plurality of components and a plurality of fasteners; and a computer operable to: receive the input parameters of the plurality of components joinable with one or more fasteners from the one or more libraries; calculate a plurality of second level parameters based on the input parameters; build a plurality of component models of the plurality of components lacking the one or more fasteners based on the plurality of second level parameters; subtract a plurality of fastener bores from the plurality of component models; generate 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 bores; apply a plurality of boundary conditions to the assembly model; apply a plurality of loads under the plurality of boundary conditions to the assembly model to generate a plurality of analysis keywords; and generate an input file suitable for finite element analysis based on the plurality of analysis keywords.
[0086]
[0095] Article 11. 11. The system of claim 10, wherein the computer is further operable to rotate component nodes of the component models to align with a fiber direction of the components.
[0087]
[0096] Article 12. 11. The system of claim 10, wherein the computer is further operable to calculate a center of curvature of the assembly model.
[0088]
[0097] Article 13. 13. The system of claim 12, wherein the computer is further operable to update component nodes of the component models based on the centroid and the curvature of the assembly model.
[0089]
[0098] Article 14. 11. The system of claim 10, wherein the computer is further operable to assign materials to the plurality of component models.
[0090]
[0099] Article 15. 11. The system of claim 10, wherein the computer is further operable to add one or more additional models to the assembly model, the one or more additional models including one or more strap models, spacer models, shim models, or combinations thereof.
[0091]
[0100] Article 16. 16. The system of claim 15, wherein the computer is further operable to translate the one or more additional models within the assembly model.
[0092]
[0101] Article 17. 16. The system of claim 15, wherein the computer is further operable to rotate the one or more additional models within the assembly model.
[0093]
[0102] Article 18. 11. A non-transitory computer readable storage medium having stored thereon instructions for controlling data processing, which, when executed by a processor, cause the processor to perform a number of operations including receiving input parameters for a number of components joinable with one or more fasteners; calculating a number of second level parameters based on the input parameters; building a number of component models for the number of components lacking the one or more fasteners based on the number of second level parameters; subtracting a number of fastener bores from the number of component models; generating an assembly model by combining the number of component models with one or more fastener models for the one or more fasteners in the number of fastener bores; applying a number of boundary conditions to the assembly model; applying a number of loads to the assembly model under the number of boundary conditions to generate a number of analysis keywords; and generating an input file suitable for finite element analysis based on the number of analysis keywords.
[0094]
[0103] Article 19. 20. The non-transitory computer-readable storage medium of claim 18, wherein the operations further include rotating component nodes of the component models to align with fiber directions of the components.
[0095]
[0104] Article 20. 20. The non-transitory computer-readable storage medium of clause 18, wherein the operations further include calculating a center of curvature of the assembly model; and updating component nodes of the component models based on the center and the curvature of the assembly model.
[0096]
[0105] The present disclosure is open to embodiments in many different forms. Representative embodiments of the present disclosure are shown in the drawings and described herein. It should be understood that these embodiments are provided as illustrations of the principles of the present disclosure and do not limit the scope of the aspects of the present disclosure. To that extent, examples and limitations described, for example, in the Abstract, Background, Summary, and Detailed Description sections, but not explicitly described in the claims, should not be incorporated into the claims, either singly or collectively, by implication, inference, or otherwise.
[0097]
[0106] For the purposes of this detailed description, the singular includes the plural and vice versa, unless otherwise indicated. The terms "and" and "or" are conjunctive as well as disjunctive. The terms "any" and "all" both mean "any and all," and terms such as "including," "including," "comprising," "having," and the like each mean "including, but not limited to." Furthermore, approximation words such as "about," "almost," "substantially," "approximately," and "generally" may be used herein to mean "in, near, or near" or "within 0-5% thereof" or "within acceptable manufacturing tolerances," or other logical combinations thereof. Referring to the drawings, like numbers refer to like components.
[0098]
[0107] Although the detailed description and drawings or figures support and explain the present disclosure, the scope of the present disclosure is defined only by the claims. Although the best mode and some of the other embodiments for carrying out the present disclosure have been described in detail, there are various alternative designs and embodiments for carrying out the present disclosure as defined in the scope of the appended claims. Furthermore, the features of the embodiments shown in the drawings or the various embodiments described in the present description do not necessarily need to be understood as mutually independent embodiments. Rather, each feature described in one of the examples of an embodiment may be combined with one or more of the other desired features from other embodiments, resulting in other embodiments not described in words or by reference to the drawings. Therefore, such other embodiments are included within the framework of the appended claims.
Claims
1. A method (100) for modeling a joint (340) using a fastener (348), comprising: receiving (119) a plurality of input parameters (115) for a plurality of components (342a-342d) joinable with one or more fasteners (348); calculating (120) a plurality of second level parameters (121) at a computer (310) based on said plurality of input parameters (115); constructing (124) a plurality of component models (125a) of the plurality of components (342a-342d) lacking the one or more fasteners (348) based on the plurality of second level parameters (121); subtracting (188) a plurality of fastener bores (346a-346h) from the plurality of component models (125a); generating an assembly model (125h) by combining the plurality of component models (125a) with one or more fastener models (125c) of the one or more fasteners (348) within the plurality of fastener bores (346a-346h); applying (138) a plurality of boundary conditions (139) to the assembly model (125h); applying (140) a plurality of loads (141) to the assembly model (125h) under the plurality of boundary conditions (139) to generate a plurality of analysis keywords (143); and A method (100) comprising generating (142) an input file (145) suitable for finite element analysis based on the plurality of analysis keywords (143).
2. 2. The method (100) of claim 1, further comprising rotating (204) component nodes (129) of the component models (125a) to align with a fiber direction (203) of the components (342a-342d).
3. The method (100) of claim 1, further comprising calculating (224) a center of curvature (225) of the assembly model (125h).
4. 4. The method of claim 3, further comprising updating (132) component nodes (129) of the component models (125a) based on the center and the curvature (225) of the assembly model (125h).
5. The method (100) of claim 1, further comprising assigning (270) materials (271) to the plurality of component models (125a).
6. 2. The method (100) of claim 1, further comprising adding (244-252) one or more additional models (125d) to the assembly model (125h), the one or more additional models (125d) comprising one or more strap models (125e), spacer models (125f), shim models (125g), or combinations thereof.
7. The method (100) of claim 6, further comprising translating (244-252) the one or more additional models (125d) within the assembly model (125h).
8. The method (100) of claim 6, further comprising rotating (244-252) the one or more additional models (125d) within the assembly model (125h).
9. The method (100) of any preceding claim, further comprising reading (112) the plurality of input parameters (115) and the one or more fasteners (348) from one or more libraries (106a-106b).
10. 1. A system (300) for modeling a joint (340) using a fastener (348), comprising: one or more libraries (106a-106b) operable to store a plurality of input parameters (115) for a plurality of components (342a-342d) and a plurality of fasteners (348); The present invention includes a computer (310), receiving the input parameters (115) for the components (342a-342d) that can be joined by one or more fasteners (348) from the one or more libraries (106a-106b); calculating a plurality of second level parameters (121) based on said plurality of input parameters (115); building a plurality of component models (125a) of the plurality of components (342a-342d) lacking the one or more fasteners (348) based on the plurality of second level parameters (121); subtracting a plurality of fastener bores (346a-346h) from the plurality of component models (125a); generating an assembly model (125h) by combining the plurality of component models (125a) with one or more fastener models (125c) of the one or more fasteners (348) within the plurality of fastener bores (346a-346h); applying a plurality of boundary conditions (139) to the assembly model (125h); applying a plurality of loads (141) to the assembly model (125h) under the plurality of boundary conditions (139) to generate a plurality of analysis keywords (143); and generating an input file (145) suitable for finite element analysis based on the plurality of analysis keywords (143).
11. The computer (310) 11. The system (300) of claim 10, further operable to rotate component nodes (129) of the component models (125a) to align with a fiber direction (203) of the components (342a-342d).
12. The computer (310) The system (300) of claim 10, further operable to calculate a center of curvature (225) of the assembly model (125h).
13. The computer (310) 13. The system of claim 12, further operable to update component nodes of the component models based on the center and the curvature of the assembly model.
14. The computer (310) The system (300) of claim 10, further operable to assign materials (271) to the plurality of component models (125a).
15. The computer (310) The system (300) of claim 10, further operable to add (244-252) one or more additional models (125d) to the assembly model (125h), the one or more additional models (125d) including one or more strap models (125e), spacer models (125f), shim models (125g), or combinations thereof.
16. The computer (310) The system (300) of claim 15, further operable to translate the one or more additional models (125d) within the assembly model (125h).
17. The computer (310) The system (300) of claim 15, further operable to rotate the one or more additional models (125d) within the assembly model (125h).
18. A non-transitory computer-readable storage medium (314a) having stored thereon instructions (316) for controlling data processing, the instructions (316), when executed by a processor (312), causing the processor (312) to: receiving (119) a plurality of input parameters (115) for a plurality of components (342a-342d) joinable with one or more fasteners (348); calculating (120) a plurality of second level parameters (121) based on said plurality of input parameters (115); constructing (124) a plurality of component models (125a) of the plurality of components (342a-342d) lacking the one or more fasteners (348) based on the plurality of second level parameters (121); subtracting (188) a plurality of fastener bores (346a-346h) from the plurality of component models (125a); generating an assembly model (125h) by combining the plurality of component models (125a) with one or more fastener models (125c) of the one or more fasteners (348) within the plurality of fastener bores (346a-346h); applying (138) a plurality of boundary conditions (139) to the assembly model (125h); applying (140) a plurality of loads (141) to the assembly model (125h) under the plurality of boundary conditions (139) to generate a plurality of analysis keywords (143); and and generating an input file (145) suitable for finite element analysis based on the plurality of analysis keywords (143).
19. The plurality of operations include:
20. The non-transitory computer readable storage medium (314a) of claim 18, further comprising rotating (204) component nodes (129) of the component models (125a) to align with a fiber direction (203) of the components (342a-342d).
20. The plurality of operations include: Calculating (224) a center of curvature (225) of said assembly model (125h); and 20. The non-transitory computer readable storage medium of claim 18, further comprising updating (132) a plurality of component nodes (129) of the plurality of component models (125a) based on the center and the curvature (225) of the assembly model (125h).