Journal Article

A Laminate Parametrization Technique for Discrete Ply-Angle Problems with Manufacturing Constraints


G. J. Kennedy, and J. R. R. A. Martins


Structural and Multidisciplinary Optimization, 48(2):379–393, 2013



In this paper we present a novel laminate parametrization technique for layered composite structures that accounts for problems in which the ply angles are limited to a discrete set. In the proposed technique, the classical laminate stiffnesses are expressed as a linear combination of the discrete options and design-variable weights. An exact l1 penalty function is employed to drive the designs towards discrete, 0-1 designs. The proposed tech- nique can be used as either an alternative or as an enhancement to SIMP-type methods, such as discrete material optimization (DMO). Unlike mixed-integer approaches, our laminate parametrization technique is well suited for gradient-based design optimization. The proposed laminate parametrization is demonstrated on compliance design of laminated plates and buckling design of a laminated stiffened panel. The results demonstrate that the approach is an effective alternative to DMO methods.