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Such a cooperative plan can be described and shared in a standardized, generic and
flexible language [16], which is then interpreted and executed at run-time. The main
advantage is the writing of arbitrary Setplays, which are dynamically executed during
the game, allowing the definition of new plays which could possibly differ between
games, in order to adapt better to each opponent. Another benefit is the possibility to
swiftly react to situations identified as advantageous: a new Setplay can quickly be
edited and immediately executed. Setplays can also be used in different leagues [16].
FC Portugal team developed a complete framework for the representation, execu-
tion and evaluation of high level, flexible plans for agents playing robotic soccer. The
framework was presented in [16, 17, 22] , defining a generic Setplay definition lan-
guage and several associated tools.
To fulfill these requirements, one defined a standard language to define Setplays,
which can later be interpreted by any player in any league. The basic concepts
of soccer (moves, conditions, actions, skills) were given a clear yet comprehensive
definition.
A Setplay is built upon Steps, with alternative transitions between them. Steps
should be seen as intermediary states of the Setplay. Transitions between intermediary
steps demand the execution of actions between the players. And there are also termi-
nation conditions. This language is more thoroughly described in [18, 22].
A library has been developed in C++ to ease the implementation of Setplays in any
team. The Framework provides different tools: a parser for Setplay definition files and
an engine to manage Setplay selection and execution. Thus, to apply Setplays to a
new team, two tasks have to be done initially: implement the verification of condi-
tions and the execution of the Framework actions. To actually use the Setplays, the
team has to start the execution of the Setplay by instantiating its parameters, and regu-
larly (i.e.: in every execution cycle) update the Setplay status, supplying ball and
players positions.
The Setplay Framework was designed with the goal of being general, flexible, pa-
rameterizable and applicable to any robotic soccer league. A Setplay has a participant
list, as well as an optional list of parameters. It also has a list of Steps, that represent
intermediary states in the Setplay's execution. Transitions between steps entail the
execution of specific actions, and can be restricted by Conditions, such as a player
being in a specific field area, or having ball possession. Conditions can also be used to
trigger Setplay successful ending or abortion.
A major issue in the usage of the Framework is how to achieve coordination be-
tween the robots when executing a Setplay. Naturally, a complex Setplay must follow
several steps, and all participating players must be closely synchronized in order to
achieve fruitful cooperation. A communication and synchronization policy was de-
fined, in a straightforward and concise manner, since the 2D Simulation league has
strict communication restrictions.
Each step will be led by the so-called lead player, which will normally be the play-
er with ball possession, since it is the one taking the most important decisions, while
manipulating the ball. This player is naturally not fixed throughout the Setplay, and
will change from step to step. It will monitor the execution of the Setplay, instructing
the other players on Setplay begin, step entry and transition choice. The entry into a
new step, which is decided by the lead player in charge of the previous step, normally
implies the change of the lead player.
