Soft computing in structural dynamics

The paper is devoted to new computational techniques in structural dynamics where one tries to study, model, analyze and optimize very complex phenomena, for which more precise scientific tools of the past "were incapable of giving low cost and complete solution. Soft computing methods differ from conventional (hard) computing in that, unlike hard computing, they are tolerant of imprecision, uncertainty, partial truth, and approximation. The paper deals with an application of the bio-inspired methods, like the evolutionary algorithms (EA), the artificial immune systems (AIS) and the particle swarm optimizers (PSO) to optimization problems. Structures considered in this work are analyzed by the finite element method (FEM) and the boundary element method (BEM). The bio-inspired methods are applied to optimize shape, topology and material properties of 3D structures modeled by the FEM and to optimize location of stiffeners in 2D reinforced plates modeled by the coupled BEM/FEM. The structures are optimized using the criteria depend on frequency, displacements or stresses. Numerical examples demonstrate that the methods based on the soft computation are effective for solving computer aided optimal designproblems.