EFDEX: A Knowledge-Based Expert System for Functional Design of Engineering Systems

Abstract

This paper presents a knowledge-based system, 'EFDEX', the Engineering Functional Design Expert, which was developed using an expert system shell, CLIPS 6.1, to perform intelligent functional design of engineering systems. On the basis of a flexible, causal and hierarchical functional modeling framework, we propose a knowledge-based functional reasoning methodology. By using this intelligent functional reasoning strategy, physical behavior can be reasoned out from a desired function or desired behavior, and interconnection of these behaviors is possible when there is compatibility between the functional output of one and the corresponding functional requirement (e.g. driving input) of the next one. In addition, a complicated, desired function which cannot be matched with the functional output of any behavior after searching the object-oriented behavior base, will be automatically decomposed into less complex subfunctions by means of relevant function decomposition rules. An intelligent system for the functional design of an automatic assembly system provides an application of this intelligent design environment, and a demonstration of its methodology. In this paper, a knowledge-based functional representation scheme which integrates two popular AI representation techniques (object-oriented representation and rule-based representation) is also proposed as a prelude to a knowledge-based functional design system.

Knowledge-based functional conceptual design: Model, representation, and implementation

“…In order that conceptual design can arrive at a possible novel and promising resolution through retrieving a multidisciplinary FBS knowledge cell library, exhaustive search strategy is hired here to support design synthesis methodology. As depicted in Figure 13, we propose a design synthesis methodology that starts from analysis and representation of expected functions abstracted from design requirements, which follows closely with retrieval of satisfied FBS knowledge cells, and ends with synthesis of feasible FBS knowledge cells through backtracking of the path of functional decomposition as well as considering the ''or/and'' relationships among subfunctions (Zhang et al, 2001).…”

Conceptual Design Knowledge Management Based on Rule and User's Feedback

“…The product P is decomposed into many different function units which denoted as: 1 F , 2 F , … n F and the function 1 F can be decomposed into 11 F … n F 1 in the same way. So the process of function-decomposing is executed until a suitable solution was found.…”

“…Many overseas university, industry corporations and education institutions are working on conceptual design knowledge retrieval and knowledge reuse, such as WISE (Europe), MOKA (Europe), NIST (America) and LG (Korea). And many archetypal systems for conceptual design knowledge support have been developed, such as A-Design System, Scheme builder, Kristik and Ideal, EFDEX and CSCCD etc [1,2].…”

Research on Effect Evaluation for Conceptual Design

“…The above effect model can be combined to effect chains to realize the input and output conversions [7,8].Although effects and/or effect library are getting more and more important nowadays, how ever for a certain function requirement are usually correlated with multiple effects and/or effect chains. How to select a suitable effect, and a selection of evaluation criteria etc are getting more and more important than ever [9]. For this reason, this paper put forward a set of suitable evaluation indexes, evaluation algorithms etc, evaluating cases are exemplified in this paper.…”