Accession Number:

ADA443432

Title:

Reachable Sets for Multiple Asteroid Sample Return Missions

Descriptive Note:

Master's thesis

Corporate Author:

NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF MECHANICAL AND ASTRONAUTICAL ENGINEERING

Personal Author(s):

• Croley, Patrick A.

Report Date:

2005-12-01

Pagination or Media Count:

145.0

Abstract:

In support of future NASA asteroid sample return missions, this thesis examines strategies to reduce the number of feasible asteroid targets. Reachable sets are defined in a reduced classical orbital element space. The boundary of this reduced space is obtained by extremizing a family of convex combinations of orbital elements. The resulting group of optimization problems is solved using a direct collocation pseudospectral technique by a MATLAB application package called DIDO. The reachable sets are examined to narrow the possible valid asteroid choices in order to aid in mission design and analysis of alternative targets. A solar electric propulsion system is modeled with the stay times at each asteroid, Earth departure, and Earth arrival hyperbolic excess velocities implemented as constrained optimization parameters.

Descriptors:

• *ORBITS
• *SOLAR RADIATION
• *THRUST
• *ASTEROIDS
• *SOLAR GENERATORS
• OPTIMIZATION
• PARAMETERS
• CONVEX BODIES
• SOLAR SYSTEM
• EARTH(PLANET)
• THESES
• PROPULSION SYSTEMS
• MISSIONS

Subject Categories:

• Astronomy
• Non-electrical Energy Conversion
• Unmanned Spacecraft

Distribution Statement:

APPROVED FOR PUBLIC RELEASE