Nautilus: Wireless, interior and neutrally buoyant technology for water leak detection in big diameter pipelines Nautilus consists of a sphere which is inserted into the water system, where it travels driven by the water flow. The sound of a leak, air pocket or anomaly is recorded by Nautilus and once extracted, the collected data is processed and the precise location of the anomalies is indicated. Nautilus is used for leak inspection, network inspection and leak prevention. Water companies obtain significant information about their pipelines and focus their actions to decrease investments in the maintenance of their infrastructures. Nautilus wants to provide the market with an affordable, efficient and effective solution through a recurring-used model that helps reduce Non-Revenue Water in the world.