| The oceans have a wealth of resources useful to mankind, and the unpredictable and hazardous environments make it difficult to tap these resources directly. Remote access to the resources from land could avoid human presence in these difficult environments, and the use of remotely operated underwater vehicles is a viable means: Operating underwater vehicles with tethers requires tethers running 4 kilometers and longer. The storage of tethers with their requirement for large spools and drums increases operating costs. Further, the use of a tether decreases the efficiency of the underwater vehicle, due to the drag imposed by the tether.; The thesis presents a new class of small underwater vehicles that operate without a tether and are controlled remotely from the land. The underwater vehicle is designed for inspection of leakages in pipes, oil rigs, construction and other electromechanical devices. Vehicles that fall into this class are named “Tetherless Remotely Operated Vehicles” (TLROV). The main objective of this thesis was to develop a control and communication system between the TLROV and the operator. Ultrasonic sound signals have been used to develop the communication system. The system has been practically tested for its performance and the results are promising. |
