Evolutionary structural optimisation based on boundary representation of NURBS. Part I: 2D algorithms

This paper presents an evolutionary structural optimisation (ESO) approach based on the boundary element method. Non-uniform rational B-splines (NURBS) are used to define the geometry of the component and, since the shape of these B-splines is governed by a set of control points, use can be made of the locations of these control points as design variables. The developed algorithm creates NURBS-based internal cavities to accomplish topology changes. The optimum topologies evolve allowing cavities to merge between each other and to their closest outer boundary. Two-dimensional structural optimisation is investigated in detail exploring single and multiple load case elastic problems.