Fleet Of Autonomous Vehicles Connected Into Acoustic Network
In late July 2013, partners of the Marine Robotic System of Self-Organizing, Logically Linked Physical Nodes (MORPH) European Project concluded five-day sea trials in Toulon (FR), having successfully integrated several AUVs (Autonomous Underwater Vehicles) and ASVs (Autonomous Surface Vehicles) into a coordinated multi-node MORPH system using EvoLogics underwater acoustic communication devices.
The MORPH project was launched in February 2012 under coordination of Atlas Elektronik GmbH (DE). It advances a novel concept of an underwater robotic system composed of spatially separated mobile modules, each carrying complementary underwater sensors. The modules are connected by an acoustic underwater communication network. Without constraints of rigid links, the nodes can reconfigure themselves and place sensors in an optimized way in response to the shape of the seabed. Such system pioneers underwater habitat mapping in rugged terrain, where existing methods and technologies fail to yield good results.
Toulon experiments were dedicated to testing the MORPH Simplified Horizontal Survey Configuration, intended for mapping of three-dimensional seafloor structures - a formation of 2 USVs (Unmanned Surface Vehicles) that control and guide 2 AUVs. In this configuration, the USVs communicate over Wifi and use GPS, whereas the AUVs are connected through an underwater acoustic network and use range-only acoustic navigation.
The partners succeeded in programming and running a fleet of vehicles, performing CPF (Cooperative Path Following) maneuvers of the USVs and ROF (Range Only Formation) maneuvers of the AUVs. To demonstrate the system’s efficiency, the experiments were performed with different sets of marine vehicles from different MORPH partners - six vehicles overall. The team reached all objectives, having integrated all hardware and software systems required for mission planning and control, as well as all aerial and acoustic communications.
One of the MORPH partners, Centre for Maritime Research and Experimentation (CMRE), implemented the underwater networking solution for data exchange and positioning of underwater vehicles using EvoLogics S2CR-series underwater acoustic modems. As the trials progressed, additional EvoLogics underwater acoustic modems provided live monitoring and support of the operations.
EvoLogics had successfully cooperated with the MORPH project before. EvoLogics USBL transceiver, capable of simultaneous communication and USBL positioning, was successfully tested at previous MORPH trials in La Spezia (IT). The transceiver was customised with a “streamlined” transducer head, carefully designed to match the hydrodynamics of the SeaCat AUV from Atlas Elektronik, one of the MORPH partners.
