Liam Paull
In this paper, we study the problem of cooperative SLAM (C-SLAM) for multiple autonomous underwater vehicles (AUVs). Since the underwater environment is unstructured and difficult to sense, and the communications link between vehicles is tenuous, directly porting algorithms developed for terrestrial applications to underwater is almost impossible. To compensate, we focus on systematically reducing inter-vehicle communication overhead to make it amenable to the stringent acoustic bandwidth available. Building upon recent advancements in incremental solutions to graph-SLAM and the associated graph sparsification techniques to reduce computational complexity, in this paper, we develop a novel graph-based C-SLAM algorithm that is able to (optimally) generate communication packets whose size can be adaptive to the restrictive underwater acoustic communication channels. As a result, AUVs are not required to surface for GPS fixes during navigation, leading to significant savings in operations. The proposed algorithm is validated through marine vehicle and acoustic communication simulations.
Accepted to ICRA 2015 ... further developments to come ...