Method for representing and generating a flat pattern for a composite ply that folds over itself

A data processing system comprising:

• a processor;
• and
• an accessible memory, the data processing system particularly configured to:
• receive data defining a tool and a ply coverage, wherein the ply coverage defines a plurality of plies, a fiber orientation for each of the plies, and a boundary for each of the plies;
• determine one or more subset regions on the tool based on the boundaries from the ply coverage;
• create at least one merged ply combining at least two of the plies and aligning the fiber orientations of the at least two of the plies;
• define staging instances for each ply of the at least one merged ply which indicates the respective subset region that each respective ply covers such that the at least one merged ply is folded or is wrapped around a corner of the tool at the boundary between the at least two plies;
• determine a laydown order of the plies based on the staging instances;
• run a draping simulation using the laydown order to solve the staging instances, in which each ply of each staging instance is laid down at the respective subset region for each staging instance in the laydown order, which draping simulation takes into account thickness increase due to previously laid down plies;
• generate a flat pattern that defines a shape for cutting at least one composite ply corresponding to the at least one merged ply based on the draping simulation;
• and
• store the flat pattern of the composite ply.

A non-transitory computer-readable medium encoded with executable instructions that, when executed, cause one or more data processing systems to:

• receive data defining a tool and a ply coverage, wherein the ply coverage defines a plurality of plies, a fiber orientation for each of the plies, and a boundary for each of the plies;
• determine one or more subset regions on the tool based on the boundaries from the ply coverage;
• create at least one merged ply combining at least two of the plies and aligning the fiber orientations of the at least two of the plies;
• define staging instances for each ply of the at least one merged ply which indicates the respective a subset region that each respective ply covers such that the at least one merged ply is folded or is wrapped around a corner of the tool at the boundary between the at least two plies;
• determine a laydown order of the plies based on the staging instances;
• run a draping simulation using the laydown order to solve the staging instances, in which each ply of each staging instance is laid down at the respective subset region for each staging instance in the laydown order, which draping simulation takes into account thickness increase due to previously laid down plies;
• generate a flat pattern that defines a shape for cutting at least one composite ply corresponding to the at least one merged ply based on the draping simulation;
• and
• store the flat pattern of the composite ply.