A light and reliable aircraft has been the major goal of aircraft
designers. It is imperative to design the
aircraft wing skins as efficiently as possible since the wing skins comprise
more than fifty percent of the structural weight of the aircraft wing.
The aircraft wing skin consists of many different types of material and
thickness configurations at various locations. Selecting a thickness for each location is perhaps the most
significant design task. In this paper, we formulate discrete mathematical
programming models to determine the optimal thicknesses for three different
criteria: maximize reliability, minimize weight, and achieve a trade-off
between maximizing reliability and minimizing weight. These three model
formulations are generalized discrete resource-allocation problems, which lend
themselves well to the dynamic programming approach. Consequently, we use the
dynamic programming method to solve these model formulations. To illustrate our
approach, an example is solved in which dynamic programming yields a minimum
weight design as well as a trade-off curve for weight versus reliability for an
aircraft wing with thirty locations (or panels) and fourteen thickness choices
for each location.
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