Environmental Engineering Reference
In-Depth Information
from the master spacecraft to a “slave” spacecraft, which phase locks its laser
to the incoming beam and directs its reply back to the master. The master
then mixes the incoming light with a small fraction of its original outgoing
light to produce an interference pattern that can be processed to determine
changes in distance between the free-floating proof masses good to better
than the size of an atom. Once ground software processing (utilizing as input
data from all 6 laser links) has eliminated the many noise effects and other
perturbations that can mask the desired signal, the remaining information
can be used to detect the presence of gravity waves (whose existence is pre-
dicted by Einstein's General Theory of Relativity, but has not as yet been
directly detected), which when passing through the antenna will cause the
proof masses to move apart by an amount comparable to the sensitivity of
the measuring apparatus.
3.3 Current Levels of Flight Automation/Autonomy
To better understand where those new automation/autonomy opportunities
may reside, it is useful to associate the items on the previous list of opera-
tional activities with rough estimates of the activity's current level of flight
autonomy: “high”, “medium”, “low”, or “not applicable”. The annotated list
Activity 2, command loading, is the ground activity responsible for up-
linking data to the spacecraft. It is already a mostly automated process, and
within the next 10 years, will likely be a fully autonomous ground process.
Downlinked data capture and archiving (activities 6 and 10) also have been
automated and will probably be fully autonomous ground processes in the
Table 3.2.
Operational activities with rough estimates of current level of flight
autonomy
Current flight automation/
Activity
autonomy level
1. Planning and scheduling
Low
2. Command loading
n.a.
3. Science schedule execution
Medium
4. Science support activity execution
Medium
5. Onboard engineering support activities
High
6. Downlinked data capture
n.a.
7. Data and performance monitoring
Medium
8. Fault diagnosis
Low
9. Fault correction
Low
10. Downlinked data archiving
n.a.
11. Engineering data analysis/calibration
Low
12. Science data processing/calibration
Low
