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Characterization activities related to near-Earth asteroids (NEAs) provide several societal benefits. This work can serve
as a precursor to a human exploration mission, it can facilitate the assessment of targets for resource extraction, and it
can serve as preparation for intervention against the threat posed by an Earth impactor (EI). One objective of ongoing
work at the University of North Dakota is to develop the capabilities required for NEA characterization. A CubeSatclass
spacecraft will serve to demonstrate and test these required technologies on-orbit.
This 1U CubeSat, which is compliant with NASA ELaNA CubeSat Launch Initiative requirements, will be comprised of
standard subsystems (excluding propulsion) and a payload consisting of a visible light camera, a limited radio science
package and a GPS receiver. The craft will also feature extensive onboard computing capabilities to allow it to process
data to perform mosaicking, super-resolution and rudimentary image feature identification and analysis.
This paper focuses on the onboard computing subsystem of this spacecraft which consists of a standard flight computer
based on the AMTEL AT91SAM9G20 chipset and a supplemental processing unit based on several GumStix computeron-
module (COM) units. The key design requirement: having an always-on primary processing unit and supplemental
capabilities (including a digital signal processor) that can be powered on for use only when required and how the current
design meets these requirements is reviewed.
A detailed review of the spacecraft’s design and mission operations plan is presented. The numerous trades required to
allow the requisite payload and onboard processing hardware to fit within the size and weight limitations posed by the
1U CubeSat form factor are discussed. Finally, the paper concludes with a review of the functionality provided by the
spacecraft and the future capabilities that this functionality will facilitate.
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