MODELING OF A DYNAMIC WAVE ENVIRONMENT FOR UNMANNED SURFACE VESSEL CONTROL
Malia, Joshua F.
Bingham, Brian S.
MetadataShow full item record
Modeling and simulation methods for the seakeeping dynamics of surface vessels vary widely. Higher fidelity models often demand high computational complexity that limits application to offline computation and are not applicable to all development cycles. These models are often based on solving nonlinear fluid flow equations, which cost time and computational power. Simplified models can reduce complexity, supporting rapid development. For developing control and autonomy of small unmanned surface vessels, choosing model fidelity requires a tradeoff between the accuracy of results and complexity of simulation. This thesis compares two methods for modeling and simulating the seakeeping of a small unmanned vessel: Gazebo—an open source, real-time robotics simulator, with an extension that integrates a model for the hydrodynamic wave forces into the rigid-body dynamics engine, and AEGIR—a nonlinear motion solver that leverages a high order boundary element method and numerical methods of motion integration. The forces, motions and runtimes are compared for various wave cases. The results suggest that the simplified models generate vessel motions of acceptable fidelity for the development of autonomy, but that for certain wave environments, the differences are significant. The results provide guidance for how the simplified Gazebo extension could be improved without adding significant computational load.
RightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
Showing items related by title, author, creator and subject.
Zach, Matthew S. (Monterey, California: Naval Postgraduate School, 2016-06);Unmanned tactical autonomous control and collaboration (UTACC) is a Marine Corps experimental research initiative with the overarching aim of developing a collaborative human-robotic system of systems (SoS). This thesis ...
Systems Architecture in Failure Analysis (Applications of Architecture Modeling to System Failure Analysis) Rabikur, Alex; Giammarco, Kristin; O’Halloran, Bryan (IEEE, 2017);This paper describes research into the applicability and value of architecture modeling techniques in conducting failure analysis on a system that is currently in service. Many Systems of Systems (SoS) currently in service ...
Defining the levels of adjustable autonomy: a means of improving resilience in an unmanned aerial system Chang, Ellen M. (Monterey, California: Naval Postgraduate School, 2014-09);This thesis investigates how to design in different levels of autonomy to improve the resilience of an unmanned aerial system (UAS) by applying the Function-specific Level of Autonomy Tool (FLOAAT) developed by NASA. This ...