Plies are a layer of Composite Material that cover elements in a Structure.
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HyperX optimizes Plies to minimize weight while maintaining producibility. This is achieved through extensive capabilities to generate, visualize, and edit Plies. Read more here.
Objective: Manually define a single composite Ply on a Structure with element coverage, an orientation, and a Material.
This workflow will create a single composite Ply with manually defined element coverage on a Structure. If desired, the Ply boundaries do not have to match up with Zone boundaries. If they do not match, additional Zones will be created after clicking Apply on the Ply Manager to reflect the coverage of the new Ply.
The minimum requirements for creating a Ply are:
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Name
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Sequence
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Orientation
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Material
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Element coverage
Note
All other inputs are optional.
Step 1: Create a Ply in the Ply Manager
Open the Ply Manager Form by right-clicking on the Structure or using the button in the Composites tab of the Ribbon.
The active Structure in the Ply Manager will dictate where the new Ply is placed. Plies can be inserted into any object (top face, core, bottom face, etc) shown in the Ply Manager.
Note
Available objects in the Ply Manager are dictated by the Design Property(s) assigned to the Structure.
In the Ply Manager, select a sequence and click the "Insert a new ply" button. This will place an empty Ply into the selected sequence.
Step 2: Select Elements
The entity selection mode automatically switches to elements when this form is open, allowing individual elements to be selected. The entity selection mode can be changed as desired; see Viewport Selection.
If the Ply coverage is being defined from CAD boundary curves, the CAD-to-FEM button can be used to automatically find elements inside of the boundary. See How to Define Ply Coverage for more.
Note
Elements added to the Ply coverage must be within the Structure that was originally selected when the form was opened.
Step 3: Specify Ply Orientation
Any orientation can be specified, including non-traditional angles (i.e. other than 0,45,90, etc).
Step 4: Specify Ply Material
Right-click on the Material field and select a Material. The Ply thickness stored on the Material will be displayed in the thickness field.
Step 5: Review/Visualize Created Ply
Once created, the Ply will appear in the Structures Tree and the Ply Manager. The ply can be edited by right-clicking on it in the Tree.
Additionally, the manually generated Plies can be visualized on the model. See How to Visualize Plies.
Plies are edited from the Ply Definition form. This form can be opened from two locations, the Structures Tree or in the Ply Manager Form. Both options open the same form.
Option 1: Edit from the Structures Tree
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Locate the Ply desired to edit on the Structures Tree.
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Right-click on the corresponding node and select 'Edit'.
Option 2: Edit from the Ply Manager
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Open the Ply Manager Form.
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Edit Plies.
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Option 1: Double-click a row in the table.
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Option 2: Select Ply(s) in the table, right-click, and select "Edit Selected Plies..."
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Option 2: Select Ply(s) in the table and click the Edit button in the top-right corner.
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Objective: Import Plies from sources outside of HyperX from the Ply Manager.
There are several routes for importing Plies from external sources, both FEM and CAD. The sections below outline the steps for each.
Option 1: CATIA XML
Plies can be imported in a CAD format from the CATIA CPD workbench. In CATIA V5, this file is generated via Insert>Data Export>XML Export, with the "3D Contour" option checked.
When the file is imported, HyperX automatically populates the Ply Manager with all of the Plies contained in the file and assigns an orientation and material to each. HyperX assigns a Material to each Ply by finding one that matches the material name in the XML file. If no match is found, the Ply will not be assigned a material.
HyperX uses the ply contour data in the XML file to create a CAD curve that represents the Ply boundaries. These CAD curves are imported to the Database and assigned to the Plies during the XML import.
The final step before the Plies can be saved is to "sync" the FEM elements in the Ply. This process determines which FEM elements fall inside of the CAD boundary from CATIA. See How to Define Ply Coverage for more information.
Option 2: CATIA Plybook Spreadsheet
This format is compatible with the CATIA V5 and 3DX Virtual Ply form in the Composites Workbench. Each Ply in the Ply Manager is represented by a row in the spreadsheet. The columns dictate which Zones are covered by those Plies.
Note
The Zone names in HyperX must match the Grid Cell names in order for the spreadsheet to be compatible.
Option 3: Preview Plies
Plies in the FEM (PCOMPGs in Nastran) are imported to HyperX as "preview" Plies and will appear in the FEM Tree.
These preview Plies will be pushed into the Ply Manager once the import command is executed.
Option 4: CSV
Plies can be imported from a HyperX-specific comma-separated variable (CSV) format, which can be used for exchanging plies with custom external processes or between HyperX projects. The required format of the CSV is described below. An example of this format can also be generated by exporting the plies in the CSV format.
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Column 1 - Panel object, such as Top Face or Bottom Face.
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Column 2 - Sequence ID.
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Column 3 - Ply name.
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Column 4 - Name of ply orientation.
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Column 5 - Ply material. If a Material with matching name is not found in the Database, no material will be assigned to the Ply.
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Column 6 - Ply thickness. This value is only used for core Plies. Otherwise, the thickness on the Composite Material definition is used instead.
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Column 7 - Name of Discrete Field with per-element fiber directions for the Ply. Must be present in the Database during import for assignment to occur.
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Column 8 and beyond - IDs of FEM elements which the Ply covers.
Option 5: HDF5
Plies can be imported from an HDF5 file. Material name, orientation, and Ply coverage are read from the file.
HyperX can handle two different types of HDF5 files for Plies:
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The file can contain one set of elements, with Ply coverage defined as a subset of those elements. In this scenario, the element IDs must match those in the FEM in HyperX.
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One set of elements per Ply. This type of file is typically produced with the “CAE Exchange Format” from Fibersim. In this scenario, HyperX maps the HDF5 Ply elements onto the HyperX FEM elements to determine coverage of each Ply.
The settings below pertain to the second type of mapping:
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Exhaustive - For each HDF5 element, search through all HyperX FEM elements for the closest match. This option makes the mapping significantly slower but can improve the mapping if there are missing elements.
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Clean Up Border - This post-process checks whether FEM elements on the perimeter of the mapped Plies have centroids falling inside the HDF5 Plies. It is useful in scenarios where the edge of the HDF5 Plies fall directly on FEM mesh edges.
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Small Projection Tolerance - Used when the import is searching for FEM elements that map to HDF5 elements to improve mapping speed. This tolerance should be slightly larger than the distance.
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Max Projection Tolerance - Used when the import is searching for FEM elements that map to HDF5 elements, to resolve ambiguous mappings (such as with a “U” shaped surface).
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Coincident Grid Tolerance - Used to check for and resolve coincident grids between the HDF5 and HyperX meshes.
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Element Resolution - HyperX does not allow Plies within a Sequence to share elements; select "Skip Overlapping Elements" or "Separate Sequence" to determine how that scenario is handled.
Option 6: HyperX
This format is HyperX-specific and is meant to be used for the purpose of archiving Plies or transferring them between Projects. Each Ply in the Ply Manager is represented by a row in the spreadsheet. The columns dictate which Zones are covered by those Plies.
HyperX Plies can be exported from the Ply Manager. Four formats are available: CSV, HDF5 (single and multiple meshes), CATIA Plybook Spreadsheet, and HyperX.
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CSV - HyperX-specific and can be modified and re-imported or imported to another Project. See Import Plies for a description of the file format.
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HDF5 - Uses an industry-standard format, where FEM elements are used to define the Ply geometry. You can choose between a single or multiple mesh approach.
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CATIA Plybook Spreadsheet - Compatible with the CATIA V5 and 3DX Virtual Ply form in the Composites Workbench. See Import Plies for a description of the file format.
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HyperX - Meant to be used for the purpose of archiving Plies or transferring them between Projects. See Import Plies for a description of the file format.
A Ply can be deleted either in the Structures Tree or in the Ply Manager.
Option 1: Delete from the Structures Tree
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Locate the Ply you want to delete on the Structures Tree.
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Right-click on the corresponding node and select 'Delete'.
Option 2: Delete from the Ply Manager
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Open the Ply Manager Form.
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Select Ply(s) in the table.
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Delete Plies.
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Option 1 - Click the Delete button near the top-left of the form.
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Option 2 - Right-click and choose "Delete Selected Plies..." from the context menu.
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Objective: Define how a Composite Ply covers a Structure in HyperX.
Ply coverage can be defined either by FEM elements or CAD boundaries. However, the FEM elements are the "driving" definition and required to save the Ply to the Database (because they are needed to analyze the Ply). The intent of having FEM and CAD definitions of the Ply is to promote interfacing with tools outside of HyperX. Plies can be consumed or exported in either format.
Tip
Additionally, utilities are available to automatically convert from one format to another, a process called syncing.
Option 1: FEM Elements
Defining Coverage
Coverage with FEM elements is the most common approach used in HyperX. Any Plies that are automatically generated by HyperX will have their coverage defined with FEM elements. Additionally, Ply coverage can be directly defined with FEM elements.
CAD-to-FEM Sync Utility
If CAD boundaries were originally used to define Ply coverage (as described in option 2 below), then it is necessary to use the CAD-to-FEM syncing utility to find elements inside of the Ply boundary. This can be done one Ply at a time on the Ply Form, or for many Plies at a time on the Ply Manager. The utility simply searches through all elements in the Structure and finds those which fall inside the closed boundary(s).
Option 2: CAD Boundaries
Defining Coverage
Coverage with CAD boundaries is typically used to interface with CAD tools outside of HyperX. For example, Plies with CAD boundaries can be Imported on the Ply Manager. Alternatively, CAD curves can be imported from any source in a variety of file formats and assigned to Plies. A single outer boundary loop must be defined, with optional (multiple) inner boundaries.
FEM-to-CAD Sync Utility
If FEM elements were originally used to define the Ply coverage, the FEM-to-CAD sync utility can be used to automatically generate CAD boundaries that pass through nodes on the boundary of the FEM elements. This can be done on Ply at a time on the Ply Form, or for many Plies at a time on the Ply Manager.
This utility requires that a CAD Tool Surface be selected on the Ply form. The generated boundaries are projected to the tool surface. A CAD Tool Surface can be assigned to a Ply in the field at the bottom of the Ply form.
Note
Multiple Plies can be edited simultaneously (by selecting multiple in the Ply Manager), allowing the CAD surface to be assigned to multiple Plies at once.
After assigning the CAD surface, click apply on both the Ply Form and the Ply Manager. This is required to enable the sync button. The generated boundaries are automatically assigned to the Ply and also added to the CAD Tree.
There are settings available for the utility that allow control over the boundary curve fitting. It is recommended to adjust the slider bar settings first when adjusting the curve fits.
Vertices - Defines how many curve segments the boundary will be broken into. The left-most setting produces a single curve and the right-most setting produces a curve on all (or almost all) element edges.
Level of Fit - Adjusts how closely the boundary curve segments follow the grids on the boundary of the Ply.
Curve Degree - Adjusts the degree of the polynomial curves representing the Ply boundary.
Vertex Grids - This setting is related to the "vertices" setting. When the curve fitting algorithm evaluates a grid to determine if it is a vertex, it looks at N grids "ahead" and "behind" that grid to calculate a local radius of curvature. This radius is used to determine if the grid is on a corner. A higher value of N smooths the impact of a jagged Ply boundary.
Sync deletes existing curves - If active, the CAD boundaries currently assigned to the Ply will be deleted and replaced with the newly generated boundaries. Otherwise, the generated boundaries will replace the existing ones on the Ply, but the existing curves will not be deleted.
Generate composite curve - If active, the generated boundaries will be assembled into a single composite curve. Otherwise, many curves will be generated depending on the number of vertices in the boundary.
Objective: Enable Ply visibility and adjust Ply display setting for optimum view.
Visibility of Plies
Plies appear under a "Plies" node in the Structures Tree under their parent Structure. Each Ply can be individually toggled on or off. Additionally, all Plies can be hidden or shown using the toggle near the top of the Structure Tree as indicated below.
Note
This toggle is off by default because Plies can be slow to render on large models with many Plies.
Ply Display Mode
There are two modes viewing Plies on the model. Note that the ply visibility options described above must be active. The options are found in the View section of the Composites tab of the Ribbon.
Topological View
In this mode, Plies are "draped" over one another to mimic the appearance of a physical ply layup. Ramps will appear between thicker and thinner regions
Exploded View
In this mode, Plies are shown with a uniform offset from the FEM regardless of how many Plies are beneath them.
Ply View Settings
The following settings can be used to modify either of the ply display modes described above.
Ply Boundaries Toggle
This option is found on the "View" section of the Composites tab of the Ribbon. When active, the surfaces of the Plies will be hidden, leaving only the edges of the Plies visible. This can be useful for visualizing the locations of ply drops for many lies simultaneously.
Ply View Options
Also found in the "View" section of the Composites tab of the Ribbon, this button opens the Ply View Options form, shown below.
Note
These settings are for display purposes only and do not affect the composite analysis.
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Ply Thickness - Controls the thickness of the displayed Plies relative to the total height of the Plies. Moving the slider to the left will cause gaps to appear between Plies. Moving the slider all the way to the right will close the gaps completely and cause adjacent Plies to touch.
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Ply Drop-Slope - Defines length of ply drop ramp by number of elements from the ply drop location. The slider has discrete settings corresponding to number of elements. Moving the slider all the way to the left gives a smooth ramp. Moving the slider all the way to the right removes the ramp and shows the Plies as being discontinuous.
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Ply Scale - Controls the scale of the total Ply stack relative to the "actual" stack height (independent of the setting above). Moving the slider all the way left will display the Plies to-scale on the FEM. However, individual Plies are usually very thin relative the overall size of the Structure and it can be difficult to see detail such as ply drops at this scale. Moving the slider all the way to the right will display the Plies at a significantly exaggerated scale for improved visibility.
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Core Scale - Same behavior as Ply Scale slider, but applied to the core (when using a foam or honeycomb sandwich).
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Core Ramp Angle - Controls the angle of the core ramp, when present. This setting is only an approximation because the start and end of the core ramp must always fall on an element edge (because the visualizations are FEM-based). Additionally, the setting applies to the to-scale core (core scale slider all the way left).
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Render as Solid - Controls whether the bottom surface of the Plies is drawn. This option is off by default to reduce rendering time. However, it is useful to turn this option on when Ply thickness is reduced and there are gaps between Plies to prevent the plies from appearing hollow.
Example of core and Plies drawn simultaneously:
Ply Section Cut
This tool is used to provide a cross-section views of Plies and core. It is accessed from the "View" section of the Composites tab of the Ribbon. The button brings up a small menu with buttons to draw and clear the section cut.
To draw the section cut:
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Click the "Draw Cut Line" button.
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Click in the Viewport to define the start of the line.
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Click again to define the end of the line.
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Any Plies to the left of the vector formed by these two points will be removed.
Note
Although the Clipping Plane can be used to slice through Plies to view their interior, it is inferior for viewing Ply cross-sections (doesn't redraw faces on the cut plane).