• Dr. Alireza Esna Ashari
  • Georgia Institute of Technology
  • 104D Surge Building
  • 4:00 p.m.
  • Faculty Host: Dr. Mazen Farhood

Any practical system is subject to various major changes, as well as the unknown faults, which may change the behavior of the system and may lead to significant performance degradation and serious damages. We need to detect abnormal behaviors of the system before taking further action. Active detection methods use various types of interaction with the system to improve the detection of faults. A test signal, designed to highlight faults and variations, is fed into the system. Unlike passive approaches, active fault detection methods can guarantee the detection of faults under certain conditions. Observer and filters are designed for online monitoring of the system. Once the problem is detected, we can re-adjust the nominal controller for the new situation. This talk will provide an overview of the relevant theory and recent results in this area.

After designing observers and controllers, we implement the methods on digital computers. Computational errors and software bugs, however, may lead to failures.  We need to develop reliable software for safety-critical dynamic systems and validate them formally, before practical tests. For that purpose, we translate fault detection and control properties and proofs to machine language. We include the translated properties in software in the form of non-executable annotations. The standard annotations can be validated by automatic software verification tools.

Biography:

Alireza Esna Ashari is a postdoctoral fellow with the School of Aerospace Engineering and College of Computing at Georgia Institute of Technology. He received his Ph.D. from University of Paris-Est, working at Inria (the French National Institute for Research in Computer Science and Control), Paris-Rocquencourt center, France. After his Ph.D., he was a postdoctoral research associate with Inria. His primary research goals are directed towards developing fault detection, estimation and control methods for robust resilient safety-critical systems, as well as large-scale and networked systems.