Glossary - Autonomous and Autonomic Systems - page 249

Primarily related to definitions of goals and policies (perhaps as derived
from self-reflection).
Self-governing The capability of operating autonomously and being
responsible for achieving goals and performing tasks.
Self-healing In the reactive sense, the capability of self-fixing faults; in the
proactive sense, the capability of predicting and preventing faults.
Self-managing The capability of operating autonomously and being
responsible for wider self-* management.
Self-optimizing A system's capability of dynamically optimizing its own
operation.
Self-organizing A system's capability of organizing its own efforts. Often
used relative to networks and communications.
Self-protecting A system's capability of protecting itself through percep-
tion of potential threats and prediction of outcomes of situations in the
environment, and through self-configuring to minimize potential harm.
Self-reflecting The capability of assessing routine and reflex operations of
self-* operations and determining whether they are as expected. May in-
volve self-simulation to test scenarios.
Self-simulation The capability of generating and testing possible scenarios
without affecting the live system.
Selfware Self-managing software or firmware.
Sensor In the context of autonomic capabilities, a means to measure a part
of the managed component. In an ACS context, a measuring device whose
output can be used to determine the spacecraft's attitude, either in abso-
lute or relative terms.
Situated and autonomic communications Local, self-managed infor-
mation flows in reacting to environment and context changes. Refers to
the communication and networking vision of being task- and knowledge-
driven and fully scalable.
Slew A large change in orientation, e.g., a large attitude maneuver by a
spacecraft.
South Atlantic Anomaly A region of space near the Earth over the south
Atlantic ocean where the van Allen radiation belt makes its closest ap-
proach to the Earth's surface, with increased intensity of radiation.
Star tracker A star detecting device used for spacecraft attitude determi-
nation and control. Stars registering an intensity above a commanded
threshold are detected and tracked until a break-track is ordered. While
the star is being tracked, the star tracker measures the location of the star
in the field of view (FOV), as well as the star's magnitude. For early star
trackers, the output was location and magnitude, but recently quaternion
star trackers have been flown that output an attitude quaternion (relative
to the tracker frame as opposed to the body frame) directly.
Station-keeping maneuver A spacecraft orbital maneuver performed to
null errors in the actual orbit relative to the desired orbit.