Towards a Consistency Management in a Feature-Based Design

It is a common goal in the development of feature-based design systems to support users with extended facilities, such as comprehensive semantically correct feature-based models, conformability of tools to user requirements and to different applications, and communication via standardzed interfaces. However, the current state of the art in feature-based design does not meet the most of these requirements, particularly the integration of design, reliability and maintainability of constraints. This paper presents recent research on design by features using the constraint satisfaction approach. We determine the basic requirements for defining and administering constraints in feature-based models and propose an architecture for consistency management in feature-based design systems. The two main modules of interest are Feature Frame and Consistency Manager. The Feature Frame intends to enclose different feature data into one information set, called Feature Resources and to create and manipulate such resources using Feature Mechanisms. The Consistency Manager provides functionality for definition, evaluation and satisfaction of constraints in feature-based models. Furthermore, in this paper the relation between feature-based design, consistency management and object-oriented paradigm is clarified. In contrast to previous publications where features and constraints are associated with objects in a programming language sense, our starting point is the ontological view to the object concept. We advocate that features and constraints are not objects themselves, but attributes and laws assigned by us to objects to describe properties of them. Thus, feature-based design can be characterized as the art of defining and manipulating properties of design objects