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5.
Navigation
a graph rather than as a series of wide open meadows. For
instance, there are walls to follow, corridors to track along, and
a warren of footpaths in what initially appears to be a room.
Thus,
as have others (e.g. [Kadonoff et al. 86; Wong and
Payton 87]), we have broken our navigation system into a
tactical component and a strategic component. The tactical part
knows how to follow each of the types of paths that are found in
the robot's world, while the strategic part knows when to switch
between them. The strategic component's job is made much
easier by using the paths intrinsic to the environment. For
instance, every twis ...