Programming for AFP/ATL

VERICUT Composite Programming (VCP) reads CAD surfaces and ply boundary information and adds material to fill the plies according to user-specified manufacturing standards and requirements. Layup paths are then linked together to form specific layup sequences and output as NC programs for the automated layup machine.

Creating AFP/ATL Paths
AFP/ATL programming software reads CAD surfaces and ply boundary information and adds material to fill the plies according to user-specified manufacturing standards and requirements. Lay-up paths are then linked together to form specific lay-up sequences.

Overview of the path creation process:

  1. Read the layup surface model from CATIA V5, NX, STEP, or ACIS
    • Other model formats available.
       
  2. Read ply geometry and information from FiberSIM, CATIA or other geometry formats
    • Boundary geometry
    • Ply direction
    • Start points
       
  3. Experiment with various layup path stategies. There are several factors that affect the kind of path trajectories that can be laid on a given surface: Tool surface curvature – surface curvature determines the steering required to maintain the desired ply direction.
    • Material steering limits – the extent composite material can deform over curved areas. Steering limit affects the ability to meet the desired ply direction.
    • Ply direction tolerance – material must lay in a certain direction, but its ability to meet the exact direction is affected by tool surface curvature and material steering limits.
    • Course widths – when laying material over highly curved areas, the course width must be narrower because of the roller’s ability to compact the material. The course width affects where gaps and overlaps occur.
    • Overlap/gap allowance – gaps and overlap are created where the tows get dropped as courses converge together. Course width, direction tolerance and steering can be adjusted to affect overlap/gap placement.

    Path trajectory methods:
    • Rosette: lay material at a desired angle relative to a specified rosette axis system.
    • Natural: an un-steered path; either edge of the tow are the same length as it proceeds across the curved surface.
    • Parallel: each course is parallel to the previous one, and depending on the curvature of the surface, parallel paths induce steering, and they may deviate from the desired ply angle, but they won’t have laps or gaps.
    • Limited Steering: the course trajectory is varies between the material’s steering limit and desired rosette direction.
    • Limited Parallel: a variation of parallel trajectory, where the courses are parallel as much as po-sible until the direction deviates too greatly from the desired ply direction.
    • Guide Curves: precisely control the path direction by laying courses parallel to one or more guide curves.
       
  4. Add thickness for the current ply or sequence, for subsequent layup sequences
    • Even on relatively flat layup surfaces, added material for pad-ups or the addition of core material can create challenging surface curvature for path creation.
       
  5. Link paths to create lay-up sequences
    • Automatically and/or manually link paths based on shortest distance and the form’s topology.
    • Evaluate how the layup strategy may affect ply creation.
       
  6. Export the as-laid material geometry for further analysis in existing engineering systems.