AERIAL VEHICLE AND UNDERWATER ROBOT RESCUE SYSTEM

Abstract

"Many underwater rescues rely on the coordination of aerial, surface and underwater elements working together to achieve swift recovery of lives and hardware. To achieve this, autonomous underwater vehicles with a variety of applications have been developed to operate individually as well as in groups to widen the search coverage within the same duration. Although advances in technology permit swarms of vehicles to simultaneously conduct a search and rescue, effective communications to coordinate the entire rescue effort is a concern. Methods need to be implemented in order to support room for further expansion and permit easy deployment of additional units to the scene of an underwater rescue.

This dissertation provides an investigation into underwater communications in order to suggest possible implementations for an existing rescue system. The underwater environment presents severe difficulties to communications compared to terrestrial models. Several methodologies are discussed, and two are selected after consideration of their respective strengths and weaknesses. The work proceeds on to the construction of prototypes using RF as well as ultrasound to ascertain their feasibility and simulates orthogonal frequency division multiplexing (OFDM) as a means to propagate data with greater robustness and improved range. The environment used is an Olympic sized swimming pool to simulate the conductivity of water in less than ideal conditions and attempt to obtain short range communication functionality. The results demonstrate an acceptable level of success in line with the goals set down. The scale of the project requires that further work has to be done to complete the system and directions for further improvements are proposed. "