A design task usually begins with a conceptual design phase where requirements and objectives are defined and synthesized into design alternatives. In a traditional approach, the decision making is mainly based on the designer’s insight, basic functions, and aesthetical aspects. Limited range of performances are evaluated and this increases the amount of post-engineering adjustments in the phase of design development. Wang believes seventy-five percent of the product life-cycle cost is determined during the preliminary phase of design. Similar statements highlighted the importance of numerical evaluation of the building performance in the conceptual design phase. Thus, Computer Aided Conceptual Design approach came into play to prevent designers from investment in poor design alternatives. Several parametric tools and computational exploration methods have been developed to support the designer considering multiple objectives such as structural and environmental performance, costs, and architectural proportions. These tools provide a repeated cycle of divergence and convergence to generate the widest possible range of alternatives and, at the same time, make it possible to meaningfully manage the search space. Accordingly, the link of parametric modeling and evolutionary search algorithms are employed. Parametric modeling, based on the consistent structure of dependencies within a problem, allows generating a population of solutions conveniently and relatively fast. An evolutionary algorithm, mainly a genetic algorithm, provides the iterative process of form generation, evaluation of solutions using a “fitness function,” modification of the population until the designer is satisfied. This paper represents the link of parametric modeling, computational simulations, and a genetic algorithm through the design case of a one-bedroom unit. The focus of the study is on the interactive procedure of form exploration that allows consideration of both technical and non-technical requirements. In this paper, first, the geometric parametrization of the problem is described. Then, it is explained how the parametric model supports the evaluation of performances including thermal demands and material cost. Second, an interactive GA-based form exploration method called ParaGen, initially introduced by Peter von Buelow, is represented. Finally, we discuss how such an interactive approach assists the designer to trade-off the preferences and make decisions.
|Keywords:||Decision Making, Evolutionary Design, Design Evaluations|
Doctoral Candidate, Taubman College of Architecture and Urban Planning, University of Michigan, Ann Arbor, Michigan, USA