Most structural products have complex geometry to meet
customer's demand of high functionality with enhanced
structural stability. However, manufacturing those
products in one piece requires sophisticated methods of
manufacturing processes that will increase the total
production cost. For this reason, most structural products
are multi-component structures: they are made of number
of components and these components are assembled into
the final structure. Generally, designing a multi-component
structural product requires designers to decompose overall
product geometry in to the components set at some point
during the design process. The components set decided there
will be assembled into the final product. This research
presents methods that systematically decompose product
geometry into the components set considering the structural
stiffness of the end product. Methods of parameterizing
components set of a structure are represented by using the
structural topology graph. The structural stiffness of the
assembled structure for the given components set is evaluated
as one of the objective functions by using the FE analysis.
In order to model the assembled structure with different
components set in FE, the methods of modeling the joinings
between components are presented. In addition to the structural
stiffness, the methods of evaluating the manufacturability and
assembleability of given components set are discussed and used
as the other objective functions. The Pareto optimal decompositions
for this optimization problem are obtained by combining the FE
analysis with a multi-objective genetic algorithm using graph-based
crossover, exhibiting trade-offs among the objectives including
the structural stiffness, component manufacturability (size and
simplicity), and the assembleability.