A complete architecture has been designed, developed and tested for real AUV missions. By inserting a scenario layer in the deliberative module, local maps generated in the sensor layer are used to choose and parameterize appropriate behaviours on the fly. A reactive layer has also been implemented and contributes by inhibiting goal points from the scenario layer in extremis. It has fuzzy behaviours to rapidly extricate the vehicle in case of emergency conditions. In practice, the scenario layer is rarely if ever inhibited by this reactive layer because the DFM based trajectory planning module produces safe trajectories. Tests have been carried out on the real AUV prototype RAUVER of the Ocean Systems Laboratory in open water. Whilst the experiments reached the objectives, an unforeseen problem had to be solved: bottom reverberation. Bottom reverberation appeared as obstacle data and affected computed trajectories particularly at long ranges. In practice bottom reverberation has been detected and segmented into the local map, which successfully prevented these artefacts.
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