Robust Multi-Objective aerostructural optimisation using advanced evolutionary algorithms

When designing an aircraft engineers are usually given a design or set of design points especially on operating conditions. In practice this is not usually the case that the aircraft will fly at off-design point at some instance. Even though single or multi-point optimisation produce optimal solutions at design point performance can decrease significantly at offdesign conditions. In this paper, a robust design concept is defined by two statistical sampling formulas mean and variance coupled to the optimization fitness/objective functions to produce solutions with high quality. This alternative design strategy is implemented for two practical test cases; the first case considers a Multi-Objective (MO) design optimization and the second considers a Multidisciplinary Design Optimisation (MDO) of an Unmanned Aerial System (UAS). The methodology couples an evolutionary optimiser and an uncertainty design technique to produce a set of useful Pareto non-dominated solutions. The method shows the benefits of using robust design technique for MO and MDO problems.