The basic responsibilities of the coordinator encompass integration and analysis of individual object positions reported by the observers. The integration task sums up to repetitive updating of the common representation of the scene. The data structure holding the representation is the central component of the coordinator, and is organized in four hierarchical levels with gradual increase of abstraction: (i) object positions (measurements), (ii) individual trajectories, (iii) top level objects, and (iv), trajectories of top-level objects (see fig.4).
