Artificial Intelligence for Engineering, Design, Analysis and Manufacturing


Functional device models and model-Based diagnosis in adaptive design

Ashok K. Goela1 and Eleni Strouliaa2

a1 College of Computing, Georgia Institute of Technology, Atlanta, GA 30332-0280, U.S.A.

a2 Center for Applied Knowledge Processing, Helmholtzstr. 16, 89081 Ulm, Germany


We analyze the diagnosis task in the context of adaptive design and redesign of physical devices. We identify three types of diagnosis tasks that differ in the types of information they take as input: the design does not achieve a desired function of the device, the design results in an undesirable behavior, and a specific structural element in the design misbehaves. We describe a model-based approach for solving the diagnosis task in the context of adaptive design and redesign. This approach uses functional models that explicitly represent the device functions and use them to organize teleological and causal knowledge about the device. In particular, we describe a specific kind of functional model called structure—behavior—function (SBF) models in which the causal behaviors of the device are specified in terms of flow of substances through components. We illustrate the use of SBF models with three examples from Kritik2, a knowledge system that designs new devices by retrieving, diagnosing, and adapting old device designs.

(Received July 31 1995)

(Accepted December 15 1995)


  • Design;
  • Redesign;
  • Diagnosis;
  • Functional Representation;
  • Model-Based Reasoning

Ashok K. Goel is an Associate Professor of Computer and Cognitive Science with the College of Computing at Georgia Institute of Technology in Atlanta, Georgia. He received a M.S. in Physics and Ph.D. in Computer and Information Science from the Ohio State University in Columbus, Ohio. His research interests span intelligent systems, artificial intelligence, and cognitive science. His current research explores conceptual and functional design, case-based reasoning and learning, and device models and model-based reasoning and learning.

Eleni Stroulia is a Research Scientist at the Center for Applied Knowledge Processing (FAW) in Ulm, Germany. She received a B.S. degree in Computer Engineering from the University of Patras, Greece, and M.S. and Ph.D. degrees in Computer Science from Georgia Institute of Technology i n Atlanta, Georgia. Her research interests include adaptive systems, problem solving and learning, design of physical and software systems, and man-machine interaction. Curently, she is investigating the use of functional models for the automatic configuration of the behavioral capabilities of a robotic agent, the monitoring of the agent's behavior at run time, and the diagnosis and adaptation of its functional architecture when it fails.