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Marchand, B. G.

Publications and source records attributed to Marchand, B. G..

Formations Near the Libration Points: Design Strategies Using Natural and Non-Natural Arcs

Space based observatory and interferometry missions, such as Terrestrial Planet Finder (TPF), Stellar Imager, and MAXIM, have sparked great interest in multi-spacecraft formation flight in the vicinity of the Sun-Earth/Moon (SEM) libration points. The initial phase of this research considered the formation keeping problem from the perspective of continuous control as applied to non-natural formations. In the present study, closer inspection of the flow, corresponding to the stable and center manifolds near the reference orbit, reveals some interesting natural relative motions as well as some discrete control strategies for deployment. A hybrid control strategy is also employed that combines both the natural formation dynamics with non-natural motions via input feedback linearization techniques.

Howell, K. C.↗

Summer launch options for the Genesis mission

In November 2000, the decision was finalized to delay launch to the Genesis mission from February 2001 until sometime in the following summer. Given the nature of libration point trajectories and the unique characteristics of the Genesis mission, a complete redesign of the trajectory is required. The design procedure along with the application to the Genesis redesign is discussed and the new baseline solution is presented.

Genesis↗