Thesis (M. Sc.)--Acadia University, 1997. / Includes bibliographical references.

Thesis (Ph.D.) - University of Queensland, 2005. / Includes bibliography.

This study is laid out in 8 self-explanatory sections. The Introduction sets the scene for the thesis by describing the reasoning behind the study, defines terms and introduces the reader to the markets for amphibious aircraft which drive the design requirements. An overall floatplane design methodology is developed. The advantages and disadvantages of the 2 practical float configurations are identified, which result in a basic configuration choice methodology. A method of initially estimating float dimensions and mass for a required displacement is developed from existing references and the aircraft and float databases. Initial float support structure design solutions are proposed based, again, on the information from the databases. A method of positioning the resultant float and structure configuration relative to the existing land-based aircraft centre of gravity is then developed using existing guidance on lateral and longitudinal water-borne static stability and the aircraft database. Guidance on the initial purchase price of floats is gained from a study of commercially available items. The changes in performance due to fitting floats to a conventional aircraft are studied along with a drag comparison study of the main configurations. The work on flyingboats develops an overall flyingboat design methodology which identifies key areas where design methods are required. These methods are developed leading to initial configuration choice methodologies based on a series of generalised mass, configuration and role classifications. Having decided on the overall configuration, tools are developed to choose the method of providing on-water lateral stability and to complete the initial sizing of that choice. A method of estimating initial planing bottom dimensions is developed along with step position and configuration. Tools to estimate the mass of flyingboat-specific items are developed including planing bottom structure and the choice of lateral stability method. Knowing the mass and configuration of the flyingboat allows spray estimation and detailed on-water static stability calculations to be completed to check the acceptability of the initial configuration and dimensions. Performance estimation methods including take-off and landing, aerodynamic drag and on-water dynamic stability are proposed. Logistic support infrastructure, safety and water loading are common to both floatplanes and flyingboats and these are discussed in a separate section, along with a method of allocating values to amphibious aircraft design attributes to measure the success of the design. The methodologies are then used to design 5 floatplanes and 5 flyingboats based on a crosssection of relevant aircraft specification types. This use of the methodologies illustrates that the concept of a linked series of tools to complete the rapid conceptual design of an amphibious aircraft has been successfully achieved. A discussion chapter summarises the key discoveries in each of then former chapters and a conclusion details how the study's aim to develop integrated conceptual design methodologies for waterborne and amphibious aircraft has been successfully achieved. The study's contribution to knowledge, which includes mass, sizing, performance and cost equations for both floatplanes and flyingboats, are also detailed. A list of further work is included which concentrates on the need for further empirical information to increase confidence in the methodologies. A comprehensive bibliography of relevant texts is included.

An innovative dynamics and control algorithm is developed for a dual-nanosatellite formation flying mission. The principal function of this algorithm is to use regular GPS state measurements to determine the controlled satellite's tracking error from a set of reference trajectories in the local-vertical/local-horizontal reference frame. A linear state-feedback control law--designed using a linear quadratic regulator method--calculates the optimal thrusts necessary to correct this error and communicates the thrust directions to the attitude control system and the thrust durations to the propulsion system. The control system is developed to minimize the conflicting metrics of tracking error and ΔV requirements. To reconfigure the formation, an optimization algorithm is designed using the analytical solution to the state-space equation and the Hill-Clohessy-Wiltshire state transition matrix to solve for dual-thrust reconfiguration maneuvers. The resulting trajectories require low ΔV, use finite-time thrusts and are accurate in a fully nonlinear orbital environment. This algorithm will be used to control the CanX-4&5 formation flying demonstration mission. In addition, an iterative method which numerically generates quasi periodic trajectories for a satellite formation is presented. This novel technique utilizes a shooting approach to the Newton method to close the relative deputy trajectory over a specific number of orbits, then fits the actual perturbed motion of the deputy with a Fourier series to enforce periodicity. This process is applied to two well-known satellite formations: a projected circular orbit and a J2-invariant formation. Compared to conventional formations, these resulting quasi-periodic trajectories require a dramatically lower control effort to maintain and could therefore be used to extend ΔV-limited formation flying missions. Finally, an analytical study of the stability of the formation flying algorithm is conducted. To facilitate the proof, the control algorithm is converted into a discrete-time linear time-varying system. Stability of the system is determined via discrete Floquet theory. This analysis is applied to the CanX-4&5 control laws for tracking along-track orbits, projected circular orbits, and quasi J2-invariant formations.

An innovative dynamics and control algorithm is developed for a dual-nanosatellite formation flying mission. The principal function of this algorithm is to use regular GPS state measurements to determine the controlled satellite's tracking error from a set of reference trajectories in the local-vertical/local-horizontal reference frame. A linear state-feedback control law--designed using a linear quadratic regulator method--calculates the optimal thrusts necessary to correct this error and communicates the thrust directions to the attitude control system and the thrust durations to the propulsion system. The control system is developed to minimize the conflicting metrics of tracking error and ΔV requirements. To reconfigure the formation, an optimization algorithm is designed using the analytical solution to the state-space equation and the Hill-Clohessy-Wiltshire state transition matrix to solve for dual-thrust reconfiguration maneuvers. The resulting trajectories require low ΔV, use finite-time thrusts and are accurate in a fully nonlinear orbital environment. This algorithm will be used to control the CanX-4&5 formation flying demonstration mission. In addition, an iterative method which numerically generates quasi periodic trajectories for a satellite formation is presented. This novel technique utilizes a shooting approach to the Newton method to close the relative deputy trajectory over a specific number of orbits, then fits the actual perturbed motion of the deputy with a Fourier series to enforce periodicity. This process is applied to two well-known satellite formations: a projected circular orbit and a J2-invariant formation. Compared to conventional formations, these resulting quasi-periodic trajectories require a dramatically lower control effort to maintain and could therefore be used to extend ΔV-limited formation flying missions. Finally, an analytical study of the stability of the formation flying algorithm is conducted. To facilitate the proof, the control algorithm is converted into a discrete-time linear time-varying system. Stability of the system is determined via discrete Floquet theory. This analysis is applied to the CanX-4&5 control laws for tracking along-track orbits, projected circular orbits, and quasi J2-invariant formations.

No description available.

Thesis (M.S.)--Ohio University, March, 2004. / Includes bibliographical references (p. 109-112).

Thesis (M.Phil) - University of Queensland, 2005. / Includes bibliography.

Thesis (M.S.)--Ohio University, March, 2004. / Title from PDF t.p. Includes bibliographical references (p. 109-112)

Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.