Robust design of mechanical systems via stochastic expansion

This paper discusses stochastic optimisation using Polynomial Chaos Expansion (PCE) with Latin Hypercube Sampling (LHS). PCE provides a means to quantify the uncertainty of highly non-linear structural models involving inherent randomness of geometric, material, and loading properties. PCE, specifically the non-intrusive formulation, is used to construct surrogates of stochastic responses for optimisation procedures. A standard optimisation algorithm is then used. In particular, the material properties of structural systems are assumed to be uncertain and treated as uncorrelated random variables. Implementation of the method is demonstrated for a three-bar structure and a complex engineering structure of an uninhabited joined-wing aircraft.