840 research outputs found
Nonlinear Feedback Control of Axisymmetric Aerial Vehicles
We investigate the use of simple aerodynamic models for the feedback control
of aerial vehicles with large flight envelopes. Thrust-propelled vehicles with
a body shape symmetric with respect to the thrust axis are considered. Upon a
condition on the aerodynamic characteristics of the vehicle, we show that the
equilibrium orientation can be explicitly determined as a function of the
desired flight velocity. This allows for the adaptation of previously proposed
control design approaches based on the thrust direction control paradigm.
Simulation results conducted by using measured aerodynamic characteristics of
quasi-axisymmetric bodies illustrate the soundness of the proposed approach
Automatic control of convertible fixed-wing drones with vectorized thrust
This paper proposes a control design strategy, encompassing trajectory tracking and path following, for a category of convertible aircraft with fixed wings and vectorized thrust, as exemplified by the Harrier jet aircraft and the V-22 Osprey. The approach relies on, and extends, previous works on the control of hovering vehicles (helicopters, quadrotors,...), ax-isymmetric devices (rockets, missiles,...), and fixed-wing aircraft (airplanes). In particular it exploits a common nonlinear model of aerodynamic forces exerted on the vehicle, both simple and representative of the underlying physics. Besides the unifying property of this approach, the proposed solution addresses the delicate transition problem between hovering and cruising flight, and thus the concomitant thrust tilting issue, in a novel manner with the possibility of continuously minimizing the thrust intensity, and thus energy expenditure
A novel approach to the automatic control of scale model airplanes
International audience— This paper explores a new approach to the control of scale model airplanes as an extension of previous studies addressing the case of vehicles presenting a symmetry of revolution about the thrust axis. The approach is intrinsically nonlinear and, with respect to other contributions on aircraft nonlinear control, no small attack angle assumption is made in order to enlarge the controller's operating domain. Simulation results conducted on a simplified, but not overly simplistic, model of a small airliner illustrate the soundness of the approach
Aeronautical engineering: A continuing bibliography with indexes (supplement 309)
This bibliography lists 212 reports, articles, and other documents introduced into the NASA scientific and technical information system in Oct. 1994. Subject coverage includes: design, construction and testing of aircraft and aircraft engines; aircraft components, equipment, and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics
Autonomous Vehicles
This edited volume, Autonomous Vehicles, is a collection of reviewed and relevant research chapters, offering a comprehensive overview of recent developments in the field of vehicle autonomy. The book comprises nine chapters authored by various researchers and edited by an expert active in the field of study. All chapters are complete in itself but united under a common research study topic. This publication aims to provide a thorough overview of the latest research efforts by international authors, open new possible research paths for further novel developments, and to inspire the younger generations into pursuing relevant academic studies and professional careers within the autonomous vehicle field
Aeronautical engineering: A continuing bibliography with indexes (supplement 319)
This report lists 349 reports, articles and other documents recently announced in the NASA STI Database. The coverage includes documents on the engineering and theoretical aspects of design, construction, evaluation, testing, operation, and performance of aircraft (including aircraft engines) and associated components, equipment, and systems. It also includes research and development in aerodynamics, aeronautics, and ground support equipment for aeronautical vehicles
A nonlinear approach to the control of a disc-shaped aircraft
International audienceThis paper describes a new control approach for scale-model airplanes. The proposed control solution is primarily geared towards drones whose lift surfaces can be approximated by a disc-shaped wing. Designed and analysed on the basis of a specific model of aerodynamic forces acting on the aircraft, it departs from other solutions in its capacity to handle important and rapidly changing attack angles within a large flight envelope. Simulation results illustrate its robust performance
Aeronautical engineering: A continuing bibliography with indexes (supplement 242)
This bibliography lists 466 reports, articles, and other documents introduced into the NASA scientific and technical information system in July, 1989. Subject coverage includes: design, construction and testing of aircraft and aircraft engines; aircraft components, equipment and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics
Output Regulation for Systems on Matrix Lie-group
This paper deals with the problem of output regulation for systems defined on
matrix Lie-Groups. Reference trajectories to be tracked are supposed to be
generated by an exosystem, defined on the same Lie-Group of the controlled
system, and only partial relative error measurements are supposed to be
available. These measurements are assumed to be invariant and associated to a
group action on a homogeneous space of the state space. In the spirit of the
internal model principle the proposed control structure embeds a copy of the
exosystem kinematic. This control problem is motivated by many real
applications fields in aerospace, robotics, projective geometry, to name a few,
in which systems are defined on matrix Lie-groups and references in the
associated homogenous spaces
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