Chapter 5 Robust Performance Tailoring with Tuning - SSL - MIT

(a) (b)
Figure 1-2: Artists’ concepts of Origins missions: (a) SIM [1] and (b) TPF [2].
astrophysical targets [2, 70]. The original baseline design for TPF is an infrared sep-
arated spacecraft interferometer [13]. However, as the result of a series of industry
studies at the time of this writing there are three competing architectures for TPF:
an infrared (IR) structurally-connected interferometer, an infrared formation-flown
interferometer and a visible light coronograph. Figure 1-2(b) shows an artist’s con-
cept of the SCI design proposed by Lockheed Martin. For the purpose of the work in
this thesis only the SCI architecture is considered.
1.2 Problem Statement
One problem inherent in complex system design arises due to a trade-off that occurs
over the development phase between design flexibility and the accuracy of performance
predictions. Early in the mission development, models of the proposed design are
created to assess system performance. At this stage, design alterations come at a
modest cost, but the models used to predict performance are uncertain, resulting
in low-confidence predictions. Designing the system to meet requirements across this
large uncertainty space may not be possible. In the later phases of the program, flight
components and limited integrated test data become available dramatically increasing
the accuracy of the performance predictions. However, an unfortunate consequence
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