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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Spacecraft formation flight at sun-earth/moon libration points

Tolbert, Douglas Robert, January 2009 (has links) (PDF)
Thesis (Ph. D.)--Missouri University of Science and Technology, 2009. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed August 14, 2009) Includes bibliographical references (p. 68-71).
112

Modeling and control of a biologically inspired compliant structure /

Ray, Cody W. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 39-40). Also available on the World Wide Web.
113

Stability monitoring and analysis of online learning neural networks

Yerramalla, Sampath. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains xiii, 187 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 165-172).
114

Design and simulation of advanced fault tolerant flight control schemes

Gururajan, Srikanth. January 2006 (has links)
Thesis (Ph. D.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xii, 132 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 123-128).
115

Coherent design of uninhabited aerial vehicle operations and control stations

Gonzalez Castro, Luis Nicolas. January 2006 (has links)
Thesis (M. S.)--Aerospace Engineering, Georgia Institute of Technology, 2007. / Boff, Kenneth, Committee Member ; Johnson, Eric, Committee Co-Chair ; Pritchett, Amy, Committee Chair.
116

Advanced flight control issues for reusable launch vehicles

Bevacqua, Timothy R. January 2004 (has links)
Thesis (M.S.)--Ohio University, August, 2004. / Title from PDF t.p. Includes bibliographical references (p. 185-187)
117

Development of a synthetic vision system for general aviation

Wenger, Jason Christopher. January 2007 (has links)
Thesis (M.S.)--University of Iowa, 2007. / Supervisor: Thomas Schnell. Includes bibliographical references (leaf 115).
118

Report on trip to NASA Ames Research Center Flight Dynamics and Controls Branch, January 19th-23rd, 1981

January 1981 (has links)
Christopher G. McMuldroch. / "April, 1981." / Sponsored by NASA under Grant NGL-22-009-124
119

Development of a seamless morphing wing

Petersen, Michael January 2010 (has links)
Thesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2010. / The Cape Peninsula University of Technology (CPUT) Advanced Manufacturing and Technology Laboratory (AMTL) developed an Unmanned Aerial Vehicle (UAV) Technology Demonstrator for the purpose of testing and maturing adaptronic devices. Extending the flight envelope of this unmanned aerial vehicle by increasing its range and endurance is the next step in its development. A seamless variable angle of incidence (sVAI) morphing wing is proposed to increase the lift with little coupling to drag during takeoff; and decrease the drag with little effect on lift during climb, thus increasing the total flight performance of the aircraft. CAD models of the conceptualized sVAI wing and a conventional (CON) wing, as used on the Technology Demonstrator, were modeled. Numerical analyses on these CAD models showed that the sVAI wing concept at a 4° twist decreased the ground roll distance and stall velocity by ±17% and ±31% respectively, as compared to the CON wing in standard takeoff configuration. This allowed for ± 11.7% less power required for takeoff allowing the aircraft to get to its operational altitude quicker, thus saving fuel and reducing energy losses; and increasing range and endurance. The results also showed that the sVAI wing concept could reduce the drag during climb by ± 14%, but the lift is also proportionately reduced thus having little improvement on the climb phase of flight performance. A prototype of the morphing wing was then conceptualized and designed, using a 3D CADmodeler, and then manufactured. The product development chain produced for this morphing wing included two rapid prototyping machines and reverse engineering technologies. The chain allowed for the rapid manufacturing of light weight and intricate parts. The manufactured wing is then incorporated into a test rig to compare the actual morphing ability of the prototype to the theoretical morphing ability of the CADmodel, and thus make flight performance predictions of the actual vehicle. 3D scans were taken of the prototype and then converted to 3D CADfiles. The geometrical and topographical deformation of the prototype was then compared to that of the CAD model showing an average difference of ±1.2% and ±3% at maximum positive and negative configurations, respectively. This allowed one to make the prediction that the sVAI wing will increase the performance of the Technology Demonstrator.
120

Fighter Aircraft Maneuver Limiting Using MPC : Theory and Application

Simon, Daniel January 2017 (has links)
Flight control design for modern fighter aircraft is a challenging task. Aircraft are dynamical systems, which naturally contain a variety of constraints and nonlinearities such as, e.g., maximum permissible load factor, angle of attack and control surface deflections. Taking these limitations into account in the design of control systems is becoming increasingly important as the performance and complexity of the aircraft is constantly increasing. The aeronautical industry has traditionally applied feedforward, anti-windup or similar techniques and different ad hoc engineering solutions to handle constraints on the aircraft. However these approaches often rely on engineering experience and insight rather than a theoretical foundation, and can often require a tremendous amount of time to tune. In this thesis we investigate model predictive control as an alternative design tool to handle the constraints that arises in the flight control design. We derive a simple reference tracking MPC algorithm for linear systems that build on the dual mode formulation with guaranteed stability and low complexity suitable for implementation in real time safety critical systems. To reduce the computational burden of nonlinear model predictive control we propose a method to handle the nonlinear constraints, using a set of dynamically generated local inner polytopic approximations. The main benefit of the proposed method is that while computationally cheap it still can guarantee recursive feasibility and convergence. An alternative to deriving MPC algorithms with guaranteed stability properties is to analyze the closed loop stability, post design. Here we focus on deriving a tool based on Mixed Integer Linear Programming for analysis of the closed loop stability and robust stability of linear systems controlled with MPC controllers. To test the performance of model predictive control for a real world example we design and implement a standard MPC controller in the development simulator for the JAS 39 Gripen aircraft at Saab Aeronautics. This part of the thesis focuses on practical and tuning aspects of designing MPC controllers for fighter aircraft. Finally we have compared the MPC design with an alternative approach to maneuver limiting using a command governor.

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