Implementing parametric shape grammars to capture and explore product languages

This dissertation presents advancements in the implementation of shape grammars as well as three new applications of grammars. An interpreter for implementing 2D parametric shape grammars that supports shape emergence is described for both shapes composed of straight and curved lines. The technique used by the interpreter is shown to be complete and to capture the user's intent when matching parametric shapes through a hierarchical decomposition of shape. The capabilities of the system are demonstrated through several samples including an example of automated shape generation that takes advantage of emergence and an example of interactive shape computation that allows a user to define product form.; Several shape grammars are presented as advancements to shape grammar representation and can be classified into two groups. The first group of shape grammars is used to represent product languages where the form is dictated by engineering specifications. These grammars model the beam structure and components of automobile inner hood panels and a class of axial and mixed-flow pumps used as artificial hearts. Several inner hood panel and artificial heart designs are manually generated with the grammars as samples of designs in their respective languages. Additional inner hood panel designs are generated by an optimization method working with the implemented grammar through the 2D parametric shape grammar interpreter. The second group of shape grammars is created to model product brand characteristics with the goal of capturing, representing, and, understanding brand. A detailed investigation into the history of Buick styling reveals the brand characteristics of the front view of Buick vehicles, which are then captured in a shape grammar. In total, this work demonstrates that a design tool that allows parametric shape grammars to be implemented while supporting shape emergence is an effective tool in both engineering and brand-based applications.