Dynamic Modeling and Simulation of an Autonomous Underwater Vehicle (AUV)

Abstract

Autonomous Underwater Vehicles (AUVs) have been in development in recent decades to address the difficulties and high costs of oceanic exploration, with applications including marine life monitoring, search and rescue operations, and wreck inspection. An underwater robot developed by the Interactive Robotics and Vision (IRV) Laboratory at the University of Minnesota is LoCO, a Low Cost Open-Source AUV. LoCO seeks to assist in a number of underwater applications while reducing the current high cost of entry into underwater robotics. One aspect of this underwater vehicle that is integral to its capacity as an AUV is the modeling of its dynamics, and each new AUV comes with unique geometries spanning various propulsion control methods for specializing in different underwater tasks. This thesis seeks to establish an underwater dynamic model for the robot, implement the model in a simulated setting so as to provide testing opportunities before field deployment, and compare the effectivity of the model to collected experimental data. This, in turn, will lead to the efficient development of its autonomous systems and capability to assist in underwater operations. Within this research, the dynamic models have been produced and geometry-dependent coefficients have been derived for LoCO. A simulator for the robot has also been developed that can interface with onboard software. Though the simulation agrees relatively well with experimental data collected for LoCO’s forward motion, there are still other motion modes that require further investigation. Overall, this dynamic foundation will provide for future control system and other autonomous development to further its underwater capabilities.