USA flag logo/image

An Official Website of the United States Government

Model-Based Reasoning with Temporal Belief Networks

Award Information

Agency:
National Aeronautics and Space Administration
Branch:
N/A
Award ID:
51880
Program Year/Program:
2001 / SBIR
Agency Tracking Number:
NASA1881
Solicitation Year:
N/A
Solicitation Topic Code:
N/A
Solicitation Number:
N/A
Small Business Information
Charles River Analytics Inc.
625 Mount Auburn Street Cambridge, MA 02138-4555
View profile »
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
 
Phase 1
Fiscal Year: 2001
Title: Model-Based Reasoning with Temporal Belief Networks
Agency: NASA
Contract: N/A
Award Amount: $69,999.00
 

Abstract:

Conventional approaches to spacecraft fault detection and isolation (FDI) suffer from a combinatorial explosion in trying to represent the myriad number of ways failures can occur and propagate in a modern complex spacecraft. To get around this problem, we propose to explore the feasibility of developing a model based reasoning (MBR) technique using temporal belief networks (TBN) to model only the normal operation of the spacecraft subsystems. The natural graphic representation of this approach can then take advantage of the human supervisor¿s natural ability to recognize normal and abnormal operating modes, without requiring the necessity of a detailed and lengthy search through candidate failure modes. The addition of a temporal dimension to traditional Bayesian belief network structures facilitates analysis of time-varying commands and their current and predicted effects on the spacecraft. Our proposed incorporation of sensor measurements as belief network ¿evidence¿ will allow the user to detect faults, while a ¿what-if¿ type of speculative analysis mechanism on the same network will diagnose faults. Efficient, single-pass evidence propagation algorithms, which are consistent with probabilistic semantics for representing uncertainty in complex systems, makes this TBN approach particularly suitable for real-time operational environments such as the spacecraft control stations envisioned under this approach.

Principal Investigator:

Dr. Subrat 1. Das
Principal Scientist
6174913474
sdas@cra.com

Business Contact:

Dr. Greg L Zacharias
President
6174913474
glz@cra.com
Small Business Information at Submission:

Charles River Analytics Inc.
625 Mount Auburn Street Cambridge, MA 02138

EIN/Tax ID:
DUNS: N/A
Number of Employees:
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No