**6. Conclusions**

The chapter presented a decentralised infotaxic search algorithm for a group of autonomous robotic platforms. The algorithm allows the platforms to search and locate a source of hazardous emissions in a coordinated manner without the need for a centralised fusion and control system. More precisely, this distributed coordination is achieved only by local exchange of measurement data between neighbouring platforms. Similarly, the movement decisions taken by the platforms were reached using a distributed average consensus algorithm over the whole formation. The key aspect is that individual platforms only require knowledge of their neighbours; the global knowledge of the communication network topology is unnecessary. An advantage of adopted distributed framework is that all platforms are treated equally, making the proposed search algorithm scalable and robust to the failure of a single platform. Numerical results using experimental data confirmed the robust performance of the algorithm. The main limitation of the algorithm is that the environmental parameters (such as diffusivity, the average direction and speed of the wind, particle lifetime), must be known. Future work will explore sensitivity to parametrisation and will aim to develop a team of "search and rescue" robots for further experimentation in realistic environments.

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