Validation of an Autonomous Adaptive Safety-Critical System: Lessons Learned

Bojan Cukic

Lane Department of Computer Science and Electrical Engineering

West Virginia University

(cukic@csee.wvu.edu)

ABSTRACT:

The functionality of adaptive systems evolves over time, as they improve their performance by online learning. Through judicious learning, a deployed system may be able to react to situations that were never identified and analyzed by the designer. Online adaptive systems are attracting increasing attention in application domains where autonomy is an important requirement. Long term space missions, where communication delays to ground stations are prohibitively long, and flight control systems, which deal with a wide range of environmental factors, are among the typical application domains.

Traditional software validation techniques cannot guarantee safe behavior of online adaptive systems. We will discuss challenges that this type of systems present for software verification and validation experts. Furthermore, we will present a validation methodology developed in the context of NASA Intelligent Flight Control Systems program. This methodology includes a flexible failure detection scheme and stability analysis of a learning algorithm based on Lyapunov theory. Even though our case study is very specific, the theoretical foundation of the presented validation methodology makes it generally applicable to a wide range of online adaptive systems with embedded soft-computing components.

SPEAKER:

Bojan Cukic is an Associate Professor at the Lane Department of Computer Science and Electrical Engineering, West Virginia University. He received Dipl. Ing. degree from the University of Ljubljana, Slovenia, MS and PhD in computer science from the University of Houston, TX. His research interests include software engineering, fault-tolerant computing, information assurance and biometrics.

Dr. Cukic served as the Program Committee co-chair for the 14^th IEEE International Symposium on Software Reliability Engineering (ISSRE 2003) and 8^th IEEE International Symposium on High Assurance Systems Engineering (HASE 2004). Up until recently, he served as WVU research lead at the NASA IV&V facility in Fairmont, WV. He is the co-director of the Center for Identification Technology Research (CITeR), an NSF IUCRC (Industry University Cooperative Research Center). Dr. Cukic received NSF Career Award in 2001, Research Achievement Award from NASA, Office of Safety and Mission Assurance, in 2002 and 2004 and outstanding teaching and research awards from WVU College of Engineering and Mineral Resources (1998, 2001 and 2004).