About Drop-Off Pattern

The list used to select a drop-off pattern in Local Drop Off and in Plies From Virtual Stacking can be customized through the pattern description.

This page discusses:

See Also
Creating a Local Drop-Off
Generating the Plies from the Virtual Stacking

Drop-Off Pattern Description

Drop-off patterns are described in a DropOffPatternxxx.txt file, stored under Your_Install_Path\Your_Operating_System\startup\Composites (for example E:\Install\intel_a\startup\composites\DropOffPattern1V_Symetry.txt.

The file describing a drop-off pattern looks like this:

Name   Pattern Name
Icon	  IconName.bmp
Polyline
Orientations
45
-45
Points
0   0
10  5
0   10
Polyline
Points
10  0
0   5
10  10

Name, Icon, Polyline, Orientations, Points are keywords.

  • Name
    Name displayed in the various panels where drop-off patterns are used.
  • Icon
    Name of the icon of the drop-off pattern displayed. This icon must be stored under Your_Install_Path\Your_Operating_System\resources\graphic\icons\normal
  • Polyline
Orientations
45
-45
Points
0   0
10  5
0   10
    Description of the first curve: Polyline that describes the drop off pattern lines with those sub keywords:
    • Orientation (optional): Orientation to be used by the current polyline.
    • Points: Points describing the polylines (with x axis from 0 to 10 and y axis from 0 to 10).
  • Polyline
Points
10  0
0   5
10  10
    Description of the second curve.

  • In blue, the first line
  • In green, the second line, with directions other than 45/-45.

Keywords to Manage Several Plies on Same Ramp Support

Two keywords are available to manage several plies on the same ramp support.

ForceDropOffSymmetry

Possible value: YES or NO (default value).

This keyword is optional and if not present, the default value is taken into account.

ForceDropOffSymmetry set to YES forces the plies drop-off to be symmetrized by having symmetric plies dropping on the same ramp support. 

  • Name   Pattern Name
Icon	  IconName.bmp
ForceDropOffSymmetry No
Polyline
Orientations
45
-45
Points
0   0
10  5
0   10
Polyline
Points
10  0
0   5
10  10
    results in

    (The horizontal axis represents the ramp).
  • Name   Pattern Name
Icon	  IconName.bmp
ForceDropOffSymmetry Yes
Polyline
Orientations
45
-45
Points
0   0
10  5
0   10
Polyline
Points
10  0
0   5
10  10
    results in

NbConsecutivePliesOnSameRamp

Possible value: number of consecutive plies on the same ramp. The default value is 1.

This keyword is optional and if not present, the default value is taken into account.

  • Name   Pattern Name
Icon	  IconName.bmp
NbConsecutivePliesOnSameRamp  2
Polyline
Orientations
45
-45
Points
0   0
10  5
0   10
Polyline
Points
10  0
0   5
10  10
    allows two consecutive plies to be dropped-off on the same ramp support curve.

Those two keywords can be combined:

Name   Pattern Name
Icon	  IconName.bmp
ForceDropOffSymmetry YES
NbConsecutivePliesOnSameRamp  2
Polyline
Orientations
45
-45
Points
0   0
10  5
0   10
Polyline
Points
10  0
0   5
10  10
results in

Warning: The behavior of full plies is not changed. They are not taken into account for the drop-off but remain visible in the section.

Notes:
  • Do not use symmetric keyword for nonsymmetric patterns. This may lead to unexpected results.
  • Consecutive plies on the same ramp are impossible with multi-curve patterns.