Introduction

The subject of this book concerns exactly a swarm robotic system, that is, a system composed of a number of autonomous robots, which need to interact and to cooperate to achieve a common goal. In such a context, it is useful to allow for self-organisation while designing the different parts of the robotic system. Self-organisation can be defined as the emergence of order in a system as the result of interactions among the system components. It is often observed in biology, and in particular in animal societies, not limited to social insects like ants, bees or termites (see Camazine et al., 2001, for a review). From an engineering perspective, there are multiple advantages in designing a selforganising robotic system. Among these, it is worth mentioning that such a system is inherently robust to individual failures, as it is normally redundant in its constituent parts. It can adapt to varying environmental conditions and it can maintain its organisation notwithstanding certain external perturbations.