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Hayden, Sandra

Publications and source records attributed to Hayden, Sandra.

Automated Diagnosis and Control of Complex Systems

Livingstone2 is a reusable, artificial intelligence (AI) software system designed to assist spacecraft, life support systems, chemical plants, or other complex systems by operating with minimal human supervision, even in the face of hardware failures or unexpected events. The software diagnoses the current state of the spacecraft or other system, and recommends commands or repair actions that will allow the system to continue operation. Livingstone2 is an enhancement of the Livingstone diagnosis system that was flight-tested onboard the Deep Space One spacecraft in 1999. This version tracks multiple diagnostic hypotheses, rather than just a single hypothesis as in the previous version. It is also able to revise diagnostic decisions made in the past when additional observations become available. In such cases, Livingstone might arrive at an incorrect hypothesis. Re-architecting and re-implementing the system in C++ has increased performance. Usability has been improved by creating a set of development tools that is closely integrated with the Livingstone2 engine. In addition to the core diagnosis engine, Livingstone2 includes a compiler that translates diagnostic models written in a Java-like language into Livingstone2's language, and a broad set of graphical tools for model development.

Kurien, James↗

Lessons Learned from Autonomous Sciencecraft Experiment

An Autonomous Science Agent has been flying onboard the Earth Observing One Spacecraft since 2003. This software enables the spacecraft to autonomously detect and responds to science events occurring on the Earth such as volcanoes, flooding, and snow melt. The package includes AI-based software systems that perform science data analysis, deliberative planning, and run-time robust execution. This software is in routine use to fly the EO-l mission. In this paper we briefly review the agent architecture and discuss lessons learned from this multi-year flight effort pertinent to deployment of software agents to critical applications.

Autonomous Sciencecraft Experiment (ASE)↗

An Architecture to Enable Future Sensor Webs

A sensor web is a coherent set of distributed 'nodes', interconnected by a communications fabric, that collectively behave as a single dynamic observing system. A 'plug and play' mission architecture enables progressive mission autonomy and rapid assembly and thereby enables sensor webs. This viewgraph presentation addresses: Target mission messaging architecture; Strategy to establish architecture; Progressive autonomy with onboard sensor web; EO-1; Adaptive array antennas (smart antennas) for satellite ground stations.

Mandl, Dan↗