The Trucks Domain ================= Essentially, this is a logistics domain about moving packages between locations by trucks under certain constraints. The loading space of each truck is organized by areas: a package can be (un)loaded onto an area of a truck only if the areas between the area under consideration and the truck door are free. Moreover, some packages must be delivered within some deadlines. In this domain, it is important to find good quality plans. However, for many test problems, even finding one plan could be a rather difficult task. Domain Variants =============== This domain has several variants, which altogether involve almost all the new features of PDDL3.0. For this domain, instead of a MetricTime version, we have a Time version (there is no numerical fluent). We start the description from the TimeConstraint version, because it is the closest one to the realistic problem. Trucks TimeConstraints ---------------------- The domain has four different actions: an action for loading a package into a truck, one for unloading a package from a truck, one for moving a truck, and finally one for delivering a package. The durations of loading, unloading and delivering packages are negligible with respect to the durations of the driving actions. The problem goals require that certain packages are at their final destinations by certain deadlines. Note that we have created an equivalent version, "Time-TIL", where the "within" constraints are compiled into timed initial literals. Each team can CHOOSE one of the two alternative variants. Trucks Time ----------- The operators are the same as those in the Constraints version, but there is no delivering deadline. Finding a valid plan in this version is significantly easier, but finding a plan with short makespan is still challenging. Trucks ComplexPreferences ------------------------- The operators in this version are the same as those in the Constraints version. The deadlines are modeled by preferences. Moreover, this version contains preferences over trajectory constraints. These are constraints imposing some ordering about when delivering packages, constraints about the usage of the areas in the trucks, and constraints about loading packages. Trucks Propositional -------------------- The operators in this version are similar to those in the Constraints version, with the main difference that time is modeled as a discrete resource (with a fixed number of levels). Moreover, the driving actions cannot be executed concurrently. Trucks SimplePreferences ------------------------ The operators in this domain are the same as those in the Propositional version. The difference concerns the problem goals where the delivering deadlines are modeled by preferences. Trucks QualitativePreferences ----------------------------- The operators in this domain are the same as those in the Propositional version. The difference concerns the problems goals including soft delivering deadlines. Moreover, this version includes many preferences over state trajectory constraints that are similar to those used for the ComplexPreferences version.