About Iso-Thickness Areas

Below is some information about iso-thickness areas:

• General Information
• Area Limits to Consider
• Extended Limits
• Solving Problems

General Information

An iso-thickness area is an area of the reference surface that

• Shares a common thickness (given by the stacking in this area),
• Is continuous and manifold,
• Has been relimited at each edge corresponding to a bottom slope.

Iso-thickness areas used to generate the solid or the top surface are grouped together in an iso-thickness areas group.
The selection of iso-thickness areas in group, their relimitation/completion and the way there are connected
have a strong impact on the final solid or top surface.

Once the plies have been generated as required,

• For one or several plies groups, you can:
  • Perform an automatic initialization of the iso-thickness areas to be selected,
  • Modify or complete manually the iso-thickness areas of the group.
• For each iso-thickness area, you can:
  • Generate a shell (resulting geometry),
  • Generate an offset surface,
  • Generate shell boundaries.

You can use the command Iso-Thickness Areas:

• To create iso-thickness areas. An iso-thickness areas group is automatically created.
• To edit an existing iso-thickness areas group.
  In edition mode, some functionalities of the dialog box are not active.

Area limits and extended limits options are proposed, and can be combined.

Once created, iso-thickness areas are editable on their own.

Area Limits to Consider

You can limit the ITA by a contour or a Composites geometry.
Two options are proposed:

• Iso-Thickness Area, with a contour or a geometry.
• No Thickness Area, with a contour or a geometry, or automatic computation:
  Areas without plies inside the limit are included in the ITA group, as ITA with no thickness (0.001mm) and in the top surface.
  No Thickness Area is taken into consideration when creating a top surface, not when creating a solid.

Iso-Thickness Area

Use this option to create a top surface on a specific area of a large panel: ITA are created only inside a selected contour or Composites geometry lying on the support surface of the stacking. In this example, the ply boundary is shown by the orange arrow, the selected Iso-thickness area contour by the pink arrow, and the ITA group by the green arrow.

The top surface is shown in blue.

No Thickness Area with Contour

In our example, the top surface is shown in blue. The No Thickness Area is the red color one.

Create a contour from reference elements (shown by white arrows) and select it as No Thickness Area.

The ITA group is created using the No Thickness Area contour.
The ITA group is shown by the green arrows, the No Thickness Iso-Shell is shown by the red arrow.

Resulting in the following top surface (in blue).

No Thickness Area Auto

In this example, the arrows show holes.


The contour is automatically computed, resulting in

Extended Limits

Extended limits, defined by user or automatically computed, are to compute extended ITA group, from which an extended top surface or solid can be generated.
Since we recommend not to use the reference surface boundary to create plies, the top surface below (blue) is not appropriate to create plies.
It also does not have sufficient material excess for manufacturing preparation.

Auto with Offset Value

In the example below, we have extended the ITA by an offset value of 30 mm.
The extended ITA group is shown in green, the plies boundary in orange.

The ITA group can be used to create an extended top surface, used as reference surface for the next level of plies design.
The original top surface is shown in blue.
TThe extended top surface is shown in green.

User Defined with Extended Limit and Start EOP

Use this option to extend more in a specific direction, or if no thickness areas exist.

In this example, the Extended limit is shown by the pink arrow, the Start EOP by the orange arrow and the plies boundary by the black arrow.

Since Start EOP coincide with plies on 3 sides, the ITA is extended in 3 directions.
Extended limit and Start EOP can be curves parallel to reference elements or ramp support curves.
The resulting extended ITA group is shown by the green arrow.

The extended top surface is shown by the green arrow, the original top surface by the blue arrow.


Note that

• All plies must be inside the Start EOP.
• Extended limit must be larger than Start EOP.

Iso-Thickness Areas Trouble-Shooting

You may encounter some problems while creating so-thickness areas. Below are some possible solutions.