Results 261 to 270 of about 244,139 (311)
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Formation flying in elliptical orbits
2000 IEEE Aerospace Conference. Proceedings (Cat. No.00TH8484), 2002We present a general approach to the analysis of the formation flying problem, based on FreeFlyer(R) and MATLAB(R), that is designed with spacecraft formations in mind. With this approach, we are able to quickly combine new algorithms for the initialization and control of a formation within the context of a high-fidelity operational tool. As an example,
C. Schiff, D. Rohrbaugh, J. Bristow
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A formation flying technology vision
Space 2000 Conference and Exposition, 2000Formation Flying is revolutionizing Earth and Space science and the way the space community conducts science missions. This technological transformation provides new, innovative techniques in spacecraft guidance, navigation, and control, and how the science community gathers and shares information between space vehicles and the ground.
John Bristow, David Folta, Kate Hartman
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Visual, cruise formation flying dynamics
Atmospheric Flight Mechanics Conference, 2000In order to develop a performance baseline for future cooperative, dual aircraft operations, an experimental evaluation of pilot-in-the-loop, dual aircraft system dynamics in visual meteorological conditions (VMC) was undertaken to examine pilot response time and system frequency response characteristics. Stanford University flew a Beechcraft Queen Air
Sharon Houck, J. Powell
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Formation Flying for Distributed InSAR
AIAA/AAS Astrodynamics Specialist Conference and Exhibit, 2006We consider two spacecraft flying in formation to create interferometric synthetic aperture radar (InSAR). Several candidate orbits for such in InSar formation have been previously determined based on radar performance and Keplerian orbital dynamics. However, with out active control, disturbance-induced drift can degrade radar performance and (in the ...
Daniel Scharf +4 more
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Formation Flying and Deformable Instruments
AIP Conference Proceedings, 2009Astronomers have always attempted to build very stable instruments. They fight all that can cause mechanical deformation or image motion. This has led to well established technologies (autoguide, active optics, thermal control, tip/tilt correction), as well as observing methods based on the use of controlled motion (scanning, micro scanning, shift and ...
Yvon Rio +2 more
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Fly ASH Reactivity. Formation of hydrate phases
Journal of Thermal Analysis and Calorimetry, 2001In this study the process of hydration of fly ash, produced by a municipal solid waste (MSW) incinerator, is examined in water and in a solution enriched with Ca(OH)2. The examined fly ash samples are characterized by a high content of alkaline chlorides and anhydrite and by remarkable amounts of heavy metals.
P. Ubbrìaco +3 more
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Adaptive learning control for spacecraft formation flying
Proceedings of the 40th IEEE Conference on Decision and Control (Cat. No.01CH37228), 2002Considers the problem of spacecraft formation flying in the presence of periodic disturbances. In particular, the nonlinear position dynamics of a follower spacecraft relative to a leader spacecraft are utilized to develop a learning controller which accounts for the periodic disturbances entering the system model.
Haizhou Pan +3 more
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Spacecraft Formation-Flying in Eccentric Orbits
AIAA Guidance, Navigation, and Control Conference and Exhibit, 2003In this paper the value and possibility of eccentric orbits in formation flying mission are illustrated in detail. A new set of closed-form formulae that can be used in the formation design of eccentric orbits are derived by linearizing a general solution, which describes relative motion of two spacecraft in arbitrary elliptic orbits of 1 0 < ≤ e . The
Heng Zhang, Lan Sun
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Forcing your butterflies to fly in formation
Accident and Emergency Nursing, 1998Effective presentation involves the ability to communicate a message to an audience to produce a desired change in their understanding or opinion. It sounds simple enough for nurses, who usually pride themselves on excellent communication skills. However, for many, the prospect of standing up and speaking in front of others is terrifying.
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