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The goals of this thesis are to modify a full-scale personal hovercraft to perform autonomous maneuvers on flat ground, develop a first principles of the craft, and present data on the vehicle behavior in field trials. The hovercraft, initially designed for manual control by a rider, was modified both physically and with software to allow for remote and autonomous operation. The design leverages the actuator control solutions that are already implemented on the hovercraft for ease of installation and control. A key modification made in the design is the addition of auxiliary fans to increase overall thrust. Controller designs are presented to manage the rotation rate of the added fans. The purpose of the dynamic model is to assist in the design and evaluation of model-based controllers for the vehicle speed and heading. A first principles model was developed to give an approximate understanding of the vehicle's behavior. Data collected during field trials was used to challenge the assumptions made in the first principles model. Based on the field data, the model was updated to provide a better basis to evaluate model based controllers. Additionally, several key observations about the hovercraft performance were noted during the field trials. Controlling the vehicle heading is a nontrivial task and will require a responsive and authoritative controller

A Computational Fluid Dynamics (CFD) tool is developed in this thesis to solve complex fluid-structure interaction (FSI) problems. The fluid domain is based on Smoothed Particle Hydro-dynamics (SPH) and the structural domain employs large-deformation Finite Element Method (FEM). Validation tests of SPH and FEM are first performed individually. A loosely-coupled SPH-FEM model is then proposed for solving FSI problems. Validation results of two benchmark FSI problems are illustrated (Antoci et al., 2007; Souto-Iglesias et al., 2008). The first test case is flow in a sloshing tank interacting with an elastic body and the second one is dam-break flow through an elastic gate. The results obtained with the SPH-FEM model show good agreement with published results and suggest that the SPH-FEM model is a viable and effective numerical tool for FSI problems. This research is then applied to simulate a two-dimensional free-stream flow interacting with a deformable, pressurized surface, such as an ACV/SES bow seal. The dynamics of deformable surfaces such as the skirt/seal systems of the ACV/SES utilize the large-deformation FEM model. The fluid part including the air inside the chamber and water are simulated by SPH. A validation case is performed to investigate the application of SPH-FEM model in ACV/SES via comparison with experimental data (Zalek and Doctors, 2010). The thesis provides the theory of the SPH and FEM models incorporated and the derivation of the loosely-coupled SPH-FEM model. The validation results have suggested that this SPH-FEM model can be readily applied to skirt/seal dynamics of ACV/SES interacting with free-surface flow.

Tethered Satellites offer benefits for the space industry. Several applications are being found which utilize their unique dynamics; from sensing characteristics of the atmosphere to providing a propellantless mode of propulsion. Ground-based experimentation is useful as a cost effective means to develop a thorough understanding of tether dynamics. A number of experiments are required to fully investigate the behavior. After examining a number of experiments previously conducted, a new experiment is devised and tested. The experiment consists of designing a low friction representation of a satellite, the design of a stationary post to be tethered to the satellite representation, choosing an adequate test facility, and developing a means of acquiring data from the experiment. In order to check that the experiment is a useful tool for tether analysis, a mathematical model for the system is developed and then the experimental and mathematical results are compared.