The RoboCup Teamwork Challenge addresses issues of real-time planning, re-plannig, and execution of multi-agent teamwork in a dynamic adversarial environment. Major issues of interest in this specific challenge for the 97-99 period are architectures for real-time planning and plan execution in a team context (essential for teamwork in RoboCup). In addition, generality of the architecture for non-RoboCup applications will be an important factor.
Teamwork in complex, dynamic multi-agent domains such as Soccer mandates highly flexible coordination and communication to surmount the uncertainities, e.g., dynamic changes in team's goals, team members' unexpected inability to fulfil responsibilities, or unexpected discovery of opportunities. Unfortunately, implemented multi-agent systems often rely on preplanned, domain-specific coordination that fails to provide such flexibility. First, it is difficult to anticipate and preplan for all possible coordination failures; particularly in scaling up to complex situations. Thus, it is not robust enough for dynamic tasks, such as soccer games. Second, given domain specificity, reusability suffers. Furthermore, planning coordination on the fly is difficult, particularly, in domains with so many possible actions and such large state spaces. Indeed, typical planners need significantly longer to find even a single valid plan. The dynamics of the domain caused by the unpredictable opponent actions make the situation considerably more difficult.
A fundamental reason for these teamwork limitations is the current agent architectures. Architectures such as Soar [], RAP [], IRMA [], and BB1 [] facilitate an individual agent's flexible behaviors via mechanisms such as commitments and reactive plans. However, teamwork is more than a simple union of such flexible individual behaviors, even if coordinated. A now well-known example (originally from []) is ordinary traffic, which even though simultaneous and coordinated by traffic signs, is not teamwork. Indeed, theories of teamwork point to novel mental constructs as underlying teamwork, such as team goals, team plans, mutual beliefs, and joint commitments [, ], lacking in current agent architectures. In particular, team goals, team plans or mutual beliefs are not explicitly represented; furthermore, concepts of team commitments are absent. Thus, agents cannot explicitly represent and reason about their team goals and plans; nor flexibly communicate/coordinate when unanticipated events occur. For instance, an agent cannot itself reason about its coordination responsibilities when it privately realizes that the team's current plan is unachievable -- e.g., that in the best interest of the team, it should inform its teammates. Instead, agents must rely on domain-specific coordination plans that address such contigencies on a case-by-case basis.
The basic architectural issue in the teamwork challenge is then to construct architectures that can support planning of team activities, and more importantly execution of generated team plans. Such planning and plan execution may be accomplished via a two tiered architecture, but the entire system must operate in real-time. In RoboCup Soccer Server, sensing will be done in every 300 to 500 milli-seconds, and action command can be dispatched every 100 milli-second. Situation changes at milli-second order, thus planning, re-planning, and execution of plans must be done in real-time.