Patent ID: 8494813

Claim:
A method of designing a composite panel, the panel comprising a plurality of zones, each zone comprising a plurality of plies of composite material, each ply in each zone having a respective orientation angle, and some of the plies running continuously between adjacent zones, the method comprising: a. providing a design for the composite panel comprising a set of design variables including a thickness for each of the zones, and a ply percentage for each orientation angle for each of the zones, each ply percentage identifying a percentage of plies within a zone having a particular orientation angle; b. modifying the design in a series of iterations, each iteration including: i. analyzing the current design by calculating an objective function, a set of ply evolution constraint functions each indicating a degree of ply continuity between a respective pair of adjacent zones, and one or more structural constraint functions; ii. performing a sensitivity analysis by calculating partial derivatives of the objective function for the current design with respect to a selected set of the design variables, and calculating partial derivatives of the constraint functions for the current design with respect to a selected set of the design variables; and iii. generating a new design by determining an optimum update of the design variables in accordance with the analysis in step b.i. and the sensitivity analysis in step b.ii, the above method steps are implemented by a computer.