Abstract
Three-Dimensional CAD software represents parts as trees as specification trees of feature commands used in modelling procedures. In order to utilize the vast amount of three-dimensional models that have already been created, a method for combining shapes is required. This paper presents a simple system for taking tree representations of shapes and combining them to create new shapes. The method is based on an evolutionary algorithm with modifies the structures of trees. An experimental software system is constructed and various parameters are determined from design experience.
