The proposed project is the simulation of a system to search for air vehicles whichhave splashed-down in the ocean. The system comprises a group of 10+ autonomousunderwater vehicles, which cooperate in order to locate the aircraft. The search algorithmused in this system is based on a quadratic Newton method and was developedat Sandia National Laboratories. The method has already been successfully appliedto several two dimensional problems at Sandia.The original 2D algorithm was converted to 3D and tested for robustness in thepresence of sensor error, position error and navigational error. Treating the robots aspoint masses, the system was found to be robust for all such errors.Several real-life adaptations were necessary. A round-robin communication strategywas implemented on the system to properly simulate the dissemination of informationthroughout the group. Time to convergence is delayed but the system stillfunctioned adequately.Once simulations for the point masses had been exhausted, the dynamics of therobots were included. The robot equations of motion were described using Kane'sequations. Path-planning was investigated using optimal control methods. The VariationalCalculus approach was attempted using a line search tool "fsolve" found inMatlab and a Genetic Algorithm. A dynamic programming technique was also investigated using a method recently developed by Sandia National Laboratories. The DynamicProgramming with Interior Points (DPIP) method was a very effcient methodfor path planning and performed well in the presence of system constraints.Finally all components of the system were integrated. The motion of the robotexactly matched the motion of the particles, even when subjected to the same robustnesstests carried out on the point masses. This thesis provides exciting developmentsfor all types of cooperative projects.
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