Overcoming Representation Issues When including Aesthetic Criteria in Evolutionary Design

It is well known that for any sort of evolutionary search we must represent the problem solution in a suitable manner since the choice of representation has a large impact on the type and efficiency of the evolutionary search procedure applied. Usually in evolutionary design applications either bit strings or real number parameters are used to encode the problem. However, during the initial design phase a ‘design’ may not be decomposable into real number parameters since the nature of the search space is not well understood and / or the designer wishes to maintain a highly flexible approach whilst establishing an initial configuration. The paper introduces the overall objectives of the project and discusses representation issues before presenting an object-based representation which tries to incorporate the ambiguity present during the initial design phase by working with design elements and objects as members of the chromosome. Ambiguity is particularly acute in this case as the overall project objective is the development of a user-centric evolutionary design system that includes aesthetic criteria evaluation.