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Large satellites and exquisite planetary missions are generally self-contained. They have, onboard, all of the
computational, communications and other capabilities required to perform their designated functions. Because of this,
the satellite or spacecraft carries hardware that may be utilized only a fraction of the time; however, the full cost of
development and launch are still bone by the program. Small satellites do not have this luxury. Due to mass and volume
constraints, they cannot afford to carry numerous pieces of barely utilized equipment or large antennas.
This paper proposes a cloud-computing model for exposing satellite services in an orbital environment. Under this
approach, each satellite with available capabilities broadcasts a service description for each service that it can provide
(e.g., general computing capacity, DSP capabilities, specialized sensing capabilities, transmission capabilities, etc.) and
its orbital elements. Consumer spacecraft retain a cache of service providers and select one utilizing decision making
heuristics (e.g., suitability of performance, opportunity to transmit instructions and receive results – based on the orbits
of the two craft). The two craft negotiate service provisioning (e.g., when the service can be available and for how long)
based on the operating rules prioritizing use of (and allowing access to) the service on the service provider craft, based
on the credentials of the consumer.
Service description, negotiation and sample service performance protocols are presented. The required components of
each consumer or provider spacecraft are reviewed. These include fully autonomous control capabilities (for provider
craft), a lightweight orbit determination routine (to determine when consumer and provider craft can see each other and,
possibly, pointing requirements for craft with directional antennas) and an authentication and resource utilization
priority-based access decision making subsystem (for provider craft).
Two prospective uses for the proposed system are presented: Earth-orbiting applications and planetary science
applications. A mission scenario is presented for both uses to illustrate system functionality and operation. The
performance of the proposed system is compared to traditional self-contained spacecraft performance, both in terms of
task performance (e.g., how well / quickly / etc. was a given task performed) and task performance as a function of cost.
The integration of the proposed service provider model is compared to other control architectures for satellites including
traditional scripted control, top-down multi-tier autonomy and bottom-up multi-tier autonomy.
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