Distributed model based diagnosis and repair (DIT.5780)

Research
There is an increasing interest in developing automated systems that are able to operate in a dynamic and error-prone environment. For such autonomous systems, powerful diagnostic tools have to be used to detect possible faulty behaviour of the system without human intervention. Currently, the dominant and most successful approach to diagnosis for stand-alone systems is the model-based diagnosis approach.

Automated systems often operate in a distributive environment where other, related, systems are operating, sharing (and sometimes competing for) resources, plans and goals. Multi-agent systems technology tries to design and implement such autonomous systems (agents)operating in a common environment. It turns out that the dominant model-based diagnosis approach is not simply applicable in a distributed multi-agent context.

Research Aims
The current project therefore aims to adapt, extend and apply diagnosis methods and tools to such a distributed multi-agent system. More in particular, it aims

• to extend the classical model-based diagnosis approach for single systems to distributed multi-agent based systems. The result will be a detailed description of a multi-agent architecture for diagnosis;
• to develop distributed, multi-agent based diagnostic techniques incorporating existing single-agent based techniques. As a result, a description and prototypical implementation of a multi-agent based diagnosis system will be delivered;
• to show the feasibility of the approach by applying it to a distributed air traffic control problem. The result will be a demonstrator for diagnosis and repair in a distributed agent-based system for arrival-departure scheduling.

Utilisation
The Dutch National Aerospace Laboratory (NLR) has experience in the application of diagnostics and prognostics in aerospace applications, such as Health Management, Usage Monitoring and Aircraft Maintenance. Currently, NLR carries out a project in the area of diagnosis in Air Traffic Control (ATC).
In current Air Traffic Control (ATC), there is an increasing need for automated planning support and information sharing for operators. Due to the complex and time critical nature of ATC, this support is very difficult to provide. Although airports, airlines and ATC service providers try to optimise the efficiency of their individual "airport traffic management systems" there is little effort directed towards real integration of these systems and procedures so as to maximise the performance of the entire airport system. This situation prevents optimal use of the available capacity, both at airports and in terminal area airspace, and reduces the efficiency of the tactical Air Traffic Flow Management (ATFM) system.

Currently, NLR is executing the European LEONARDO (Linking Existing ON ground Arrival and Departure Operations) project. The main objective of this project is to define and demonstrate the feasibility of integrating airport planning and management tools. This objective will be achieved by performing an initial operational integration of existing tools for arrival and departure planning management, together with those derived from the planning and routing function of the ground movement concept at Barajas (Madrid) and Charles de Gaulle (Paris) airports. The study will be complemented with a test bench evaluation. In this context, a full-scale integration of the management and planning system at airport will be experimentally implemented under real operating conditions. The results of the operational assessment of the coordination between arrival, ground movement, and departure will provide a quantifiable measure of the benefits in terms of the safety, capacity and efficiency of the system.

This proposal for a distributed model based diagnosis and repair project is ideally suited both as an extension and follow-up of the test bench evaluation developed in the LEONARDO project:

1. The airport planning problem is an ideal test case for the proposed research as it involves multiple individual parties (such as ATC, ground control, aircraft, air transportation companies) that have cooperate in order to satisfy their, possibly conflicting, goals.
2. The tools developed in the project can be used to generate the models of the (distributed) subsystems that have to be diagnosed. Such diagnoses have to be performed frequently and efficiently as the system has to be robust for abnormalities (e.g., delays) that occur quite frequently in the domain of air transport.
3. Finally, the proposed research application is a promising one: successful solutions to the arrival and departure planning problem may have huge financial impacts, as air transport is likely to increase in the future.

NLR will apply the results of the research in a demonstrator for diagnosis and repair in a distributed agent-based system for arrival and departure scheduling.
NLR has also the intention to apply the research results in future diagnostics projects at NLR. Possibilities are the JSF (Joint Strike Fighter) project and other projects in aircraft health management and prognostics.

Er zijn vijf bedrijven en één andere universiteit bij dit project betrokken.