The European Project GREX: Coordination and Control of ...

nipulators to extend their scope of activity to rescuing missions. Some systems could
watch other systems at work to record the operations using video or they could serve as
navigation aids or communication relay stations. Multiple vehicles allow surveying wider
areas in less time, simultaneously obtaining time and space resolutions that are otherwise
unachievable. Combining pre-existing vehicles into a team will make research more
effective and will lead to completely new applications.
To coordinate and handle such groups of vehicles the research project GREX has been
created within the 6 th framework of the European Commission. The 3 years project
started in June 2006 and will end in June 2009.
The main goal of the project is to achieve a first level of distributed “intelligence” through
dependable embedded systems that are interconnected and cooperate towards the coordinated
execution of tasks. Thus the project will witness the development of theoretical
methods and practical tools for multiple vehicle cooperation, bridging the gap between
concept and practice. The technology developed must be on one hand sufficiently generic
in order to interface pre-existing heterogeneous systems. On the other hand it must
be sufficiently robust to cover problems caused by faulty communications.
Practically, developments will cover methods for effective programming of multiple systems,
coordinated mission control and navigation, formal methods for validation and testing
of the programming language, and the use of perception and communication techniques
to enable ad hoc formation of information- and sensor-networks. A series of field
trials will be carried out to assess the efficacy of the methods developed. They conclude
and demonstrate the success of the GREX project.
3. Mission Scenarios
The objectives of the GREX project are well rooted in an in-depth analysis of potential
user requirements. There are three types of mission scenarios which are the basis for
discussion and specifications. These mission scenarios envisioned take into account
challenging problems in the field of marine science. They also bring out the ever increasing
important role that marine technology is having in terms of affording marine scientist
the tools that are needed to explore and exploit the ocean. We place the focus on missions
for which the following basic ingredients are required:
• The missions require the use of several “intelligent” autonomous vehicles
equipped with appropriate instrumentation.
• The inter-vehicle coordination and mission control is dynamic and highly dependent
on the type of information obtained as the missions unfold.
The mission can be extended into various related tasks as can be found e. g. in military
missions.
Three typical scenarios are described in detail on the following pages.
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