The daedalos project was supported by the european commission under the programme transport (including aeronautics) of the 7th framework programme for research and technological development, grant agreement no: 266411. Daedalos stands for dynamics in aircraft engineering design and analysis for light optimized structures The primary objective of the daedalos project is to investigate the dynamic effects on the actual loads acting on the airframe for improved definition of the sizing loads for structural components of civil aircrafts.

A semi-analytical approach is presented for the analysis and optimization of laminated panels with nonsymmetric lay-ups, and with the possibility of introducing requirements on the buckling load, the postbuckling response and the eigenfrequencies. The design strategy relies on the combined use of semianalytical techniques for the structural analysis and genetic algorithms for the optimization. The structural analysis is performed with a highly efficient code based on thin plate theory, where the problem is formulated in terms of Airy stress function and out of plane displacement, expanded using trigonometric series. Eigenvalue analyses are performed to determine eigenfrequencies and buckling load, while an arc-length method is adopted for the postbuckling computation. The genetic algorithm is implemented with proper alphabet cardinalities to handle different steps for the angles of orientation, while specific mutation operators are used to guarantee good reliability of the optimization. To show the potentialities of the proposed optimization toolbox, two examples are presented regarding the design of balanced non-symmetric laminates subjected to linear and nonlinear constraints. The accuracy of the semi-analytical predictions is demonstrated by comparison with finite element results and benchmark cases taken from the literature.