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n order to enhance the ight envelope of Unmanned Air Vehicles (UAVs), there have been efforts to combine the excellent hover capabilities of rotorcraft with the endurance and speed performance of xed-wing aircraft. Such efforts lead to a type of agile aircraft that can perform hover coupled with ef cient ight during forward cruise. An inherent problem for such vehicles is the transition maneuver between forward ight and hover, which usually exhibits signi cant altitude variation, long transition time, large control effort, high thrust-to-weight ratio and loss of partial control. These characteristics are undesirable and reduce the maneuver potential of the vehicle in tight spaces. Moreover, the underlying ight dynamic characteristics of convertible platforms are still not fully explored. To mitigate the problems associated with the transition maneuvers above, this work proposes the use of variable-incidence wing, in which the angle of incidence of the wing with reference to the fuselage of the aircraft can be controlled during ight. This phenomenon is also referred as “aerodynamic vectoring” as the changing of the wing-incidence changes signi cantly the direction of the resultant aerodynamic force. A feasibility study of the usefulness of the variable-incidence wing scheme is conducted in comparison to a conventional xed-wing platform. The study is focusing longitudinal motion only. The lateral-directional motion is considered to be de-coupled and is out of the scope of the study. Two kinds of transition maneuvers are discussed in the thesis: Steady and Unsteady transition maneuvers. Steady transition maneuvers refer to the category in which the aircraft can sustain ight with certain pitch attitude between hover and cruise. In such transitions the aircraft can be considered to be at trim during the maneuver. Unsteady transition maneuvers refer to fast aerobatic/agile transition maneuvers between hover and cruise. In such maneuvers, the aircraft may not be in trimmed conditions between its initial and nal desired states. For the analysis, the aerodynamic forces and moments database is developed over the whole maneuver range, using windtunnel-testing. For the steady transition case, the advantages of the variable-incidence wing feature are found, however eigenvalue analysis reveals that the dynamics may have some peculiarities. For this reason, further nonlinear dynamic analysis is carried out. Speci cally, Multiple Time Scales (MTS) method in conjunction with bifurcation theory is used to uncover the peculiar system behavior and to understand the steady transition dynamics further. For the unsteady transition maneuvers, a nonlinear constrained optimization problem is formulated for parametric analyses on the effects of the thrust, pitch angle, and wing incidence on the maneuvers. Both two and three degree-of-freedom nonlinear longitudinal dynamic models are considered in the optimization study. The threedegree-of-freedom formulation gives further insight about the effects of elevator effectiveness, terminal velocity and unsteady aerodynamic phenomena on the transition maneuver. The stability of the optimal solutions is then analyzed using contraction theory. The analysis reveals that a closed-loop control is necessary for successful transitions. Strategies on controlling the transition maneuvers are discussed in the last section. Results of the contraction analysis are used to devise a simple controller to achieve stability during the maneuver. Subsequently, an improved control approach using feedback linearization is carried out. The proposed aerodynamic vectoring feature avoids possible singularities in the control architecture and is shown to improve the maneuver performance. In the end, conclusions are laid down followed by the recommendations for future research. Thesis abstracts This section presents the abstract of most recent Master or PhD thesis related to aerospace technology and management J. Aerosp. Technol. Manag., São José dos Campos, Vol.4, No 3, pp. 393-395, Jul.-Sep., 2012 393 Real Time Orbit Determination through Nonlinear Sigma-Point Kalman Filter Paula Cristiane Pinto Mesquita Pardal Instituto Nacional de Pesquisas Espaciais São José dos Campos/SP – Brazil paulacristiane@gmail.com Thesis submitted for PhD degree in Aerospace Technology at Instituto Nacional de Pesquisas Espaciais, São José dos Campos, São Paulo State, Brazil, in 2011. Advisors: Doctors Helio Koiti Kuga and Rodolpho Vilhena de Moraes

Longitudinal dynamics, optimization and control of aircraft transition maneuver using aerodynamic vectoring