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Mission Extension Using Sensitive Trajectories and Autonomous Control. Edward Belbruno Princeton University and Innovative Orbital Design, Inc. AISRP PI MEETING 2005 April 3-6, NASA Ames.
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Mission Extension Using Sensitive Trajectories and Autonomous Control Edward Belbruno Princeton University and Innovative Orbital Design, Inc. AISRP PI MEETING 2005 April 3-6, NASA Ames
Goal- Enable spacecraft to linger about a planet for extended time spans in a cost effective manner, and autonomously • Data collection is maximized for a given mission • Accomplish goal by using new sensitive/chaotic trajectories • Dynamic sensitivity saves fuel -> do more with less • Theory is weak stability boundary (WSB) theory developed by EB, 87-90 • Idea: Transition region about a planet, eg Moon, between capture and escape –>chaotic weak capture • Can achieve ballistic lunar capture transfers(~surfercatchingwave)
Operational Demonstrations • Used in 1991 to salvage Japan’s Hiten and bring to Moon -> First application of chaos to space travel -> New 90 day ballistic capture transfer • Used in 2004 to get ESA’s SMART-1 captured into lunar orbit • Ideas played a key role in 1998 salvage of Hughes HGS-1 using Moon
Approach • Two key applications: a. Motion about planet in WSB region b. Newly discovered Quasi-stationary motion • Focus on a. using Moon • WSB transfer to Moon -> ballistic capture in WSB region • Can maintain weak capture for tiny DeltaV • Demonstrated in February’s work, DeltaV is very small ~ 20 m/s for 3-4 months • Smaller the DeltaV, more unstable/complicated the motion Idea- Reduce DeltaV, require more frequent control • Optimize -> will yield control algorithm that’s autonomous