ABSTRACT

Thomas Schmickl,a Karl Crailsheim,b Jean-Louis Deneubourg,c

In collective systems, aggregation is among the essential behaviors

that have to be performed before being able to accomplish collective

tasks. Obviously, agents have to converge to some interesting

spots where collective action has to take place. However, the

biological models that are presented here show that aggregation

can also be the starting point of elaborate decision making.

Aggregation phenomena go beyond the mere gathering of agents

to a specific place. Indeed, self-organized aggregation, as defined

later, has also many interesting properties leading, for example,

to collective choices. The examples discussed here show that

aggregation and collective decision making are often tightly linked

in natural systems, as well as in bioinspired distributed technical

systems. This finding implies that-when primarily designing

algorithms for aggregation-one can get additional interesting

collective intelligence capabilities as a consequence of underlying

self-organizing mechanisms. For such systems it is an important

prerequisite that the focal collective system’s microscopic behaviors

are linked and interconnected. These characteristics make designing

for emergence a very difficult and tricky problem as many features

have to be integrated at the same time and in real time. Thus,

it is interesting to look for biological examples as sources of

inspiration that are already offering important insights into how to

solve these kinds of issues. Two biological examples are presented

here, cockroaches and honeybees, both naturally distributed and

self-organizing animal societies. These societies offer solutions

to questions like, How can we integrate many individual and

environmental features/properties in an attempt to obtain collective

intelligence at the same time as aggregation of individuals? With

relatively simple algorithms leading to aggregation, one can also get,

“for free,” many different collective patterns and complex dynamics.

These two biological examples have been successfully implemented

in robots. The case studies presented here also illustrate the

interplay between individual behavior and the perception of other

agents and the environment. Finally, we also discuss the difficulties

arising from translating biological macroscopic models of animal

behavior to microscopic robotic implementation.