Environmental Engineering Reference
In-Depth Information
needed but none was logged on, UIFA would send a request to the PAGER
agent to page the required analyst.
The VisAGE Interface Agent (VIFA) interfaced with the Visual Analysis
Graphical Environment (VisAGE) data visualization system. VisAGE was
used to display spacecraft telemetry and agent log information. Real time
telemetry information was displayed by VisAGE as it was downloaded during
a satellite pass. VIFA requested the data from the Genie Interface Agent
(GIFA) and Archive Interface Agent (AIFA) agents (see below). An analyst
could also use VisAGE to visualize historical information to help monitor
spacecraft health or to determine solutions to anomalies or other potential
spacecraft problems.
The Pager Interface Agent (PAGER) was the agent community interface
to the analyst's pager system. If an anomaly occurred or other situation arose
that needed an analyst's attention, a request was sent to the PAGER agent,
which then paged the analyst.
The Database Interface Agent (DBIFA) and the AIFA stored short-term
and long-term data, respectively, and the Log Agent (LOG) stored agent
logging data for debugging and monitoring purposes. The DBIFA stored in-
formation such as a list of the valid users and their passwords, and the AIFA
stored telemetry data.
The GenSAA/GIFA interfaced with the GenSAA/Genie ground station
software [
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], which handled communications with the spacecraft. Gen-
SAA/Genie was used to download telemetry data and maintain scheduling
information and to upload commands to the spacecraft. As anomalies and
other data were downloaded from the spacecraft, GIFA routed the data to
other agents based on their requests for information.
The Mission Operations Planning and Scheduling System (MOPSS) Inter-
face Agent (MIFA) interfaced with the MOPSS ground-station planning and
scheduling software. MOPSS kept track of the satellite's orbit and when the
next pass would occur and how long it would last. It also sent out updates to
the satellite's schedule to requesting agents when the schedule changed.
4.2.2 An Example Scenario
An example scenario illustrating how the agents would communicate and co-
operate would start with MIFA receiving data from the MOPSS scheduling
software informing MIFA that the spacecraft would be in contact position in
2 min. MIFA would then send a message to the other agents to wake them
up, if they were sleeping, and let them know of the upcoming event. The
advance notice allowed them to do some preprocessing before the contact.
When GIFA received the message from MIFA, it would send a message to the
GenSSA Data Server to put it into the proper state to receive transmissions
from the control center.
After receiving data, the GenSSA Data Server would send the satellite
data to GIFA. GIFA had a set of rules that indicated which data to send
