Guiding Self-Organization in Systems of Cooperative Mobile Agents - Advancing Artificial Intelligence Through Biological Process Applications - page 274

Figure 2. FSM of an agent showing its states and the movement behaviors associated with each state.
States are represented by circles labeled by <State/associated controller>, while arrows represent
transitions labeled by the triggering event. The initial state is marked by a filled circle.

the desired global behavior into each individual
agent, guiding the self-organizing process without
using global interactions or global controls. That
is, by indicating how the short-term goals of an
agent should change according to its general (but
local) situation, it is possible to guide groups
of agents into following a general plan or step-
by-step strategy from a higher level view of the
problem. Although the process of manually de-
signing an FSM controller requires not only good
knowledge of the problem, but also to account for
hard-to-predict interactions of the agents that can
affect the global behavior, being able to directly
represent the logic of the solution from a top level
greatly eases the difficulty of producing a desired
system-wide behavior.
In this particular case, to each state in the
FSM is associated one of four different movement

behaviors (Rodriguez, 2004). Briefly, spreading
tends to form a flock slightly similar to the broad,
V-shaped formations that migratory birds adopt
(Figure 3a). This formation is ideal for searching
for deposits, since upon seeing a deposit, an agent
will tend to ``pull'' the rest of the flock to it via
local interactions. Seeking agents go after a tar-
get, for example a unit of mineral, while avoiding
obstacles and other agents (Figure 3b). Caravan-
ing agents move in a pattern similar to spreading
agents, but they are homing on a particular point
in space (e.g., a previously visited deposit) and
thus have a narrower front (Figure 3c). Finally,
guarding agents patrol a deposit (Figure 3d),
distributing themselves about evenly through the
deposit. The interaction between nearby guarding
agents and even non-guarding agents make them
keep moving, effectively orbiting the deposit.