The (Extended) Rovers Domain [IPC-5 test domain]
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The Rovers domain was introduced in the 2002 planning competition. 
It models the problem of planning for a group of planetary rovers 
to explore the planet they are on (taking pictures and samples from 
interesting locations).


Propositional and MetricTime
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The propositional and metric-temporal versions of the domain are the same
as in IPC 2002, with the addition of some planning problems. 


QualitativePreferences
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This is the IPC 2002 propositional version with soft trajectory
constraints added (constraint types always, sometime and at-most-once are
used).  The objective is simply to maximize the number of preferences
satisfied.  The preferences are "artificial", in the sense that they do
not encode any "real" preferences on the plan, but are constructed in a
way as to make the problem of maximizing the satisfaction of preferences
challenging.


Metric with Simple Preferences [a particular case of ComplexPreferences]
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This version of the domain poses a so-called "net benefit" problem: goals
(atoms, and in some cases conjunction of atoms) have values and actions
have cost, and the objective is to maximize the sum values of achieved
goals minus the sum of costs of actions in the plan. (Only the actions
that move the rovers have non-zero cost.) The domain uses (goal state)
preferences to encode goal values and fluents to encode action costs. 
The problems are divided into three sets (p1 - p7, p8 - p13, p14 -p20)
with somewhat different structural properties.