Instantiation and Manipulation of User-Defined Freeform Features

One of the sub-topics of CAD research is the topic of feature-based design. Features are characteristic parts of a shape to which functional or parameter information can be attached. By using features in a design process, high-level interrogation and editing of a shape model is enabled. It is widely accepted that feature-based design methods should be able to handle user-defined features. Much work has been done on the definition of features and the management of feature definitions, but very little work has been done on the instantiation of these features on a target shape, especially in the domain of freeform shape. This paper discusses the current literature on freeform feature-based design and identifies the issues that play a role in the instantiation and manipulation of freeform features on target shapes. Also, a general methodology is proposed for the instantiation and manipulation of freeform features. Finally, an implementation of the proposed methods and some application examples are given.Copyright © 2008 by ASME