Chapter 5 Robust Performance Tailoring with Tuning - SSL - MIT

performance within requirements [Chapter 4].
• Extend robust design techniques to include tailoring for tuning. Define the
concept of tunability and incorporate the idea into robust optimization resulting
in a formal relationship between structural tailoring and tuning [Chapter 5].
• Demonstrate through simulation that RPTT guarantees that the desired per-
formance can be achieved given an accurate model of parametric uncertainty
[Chapter 5].
• Apply the RPTT design methodology to an integrated model of a precision
optical space structure. Choose appropriate tailoring and tuning parameters
for the focus application [Chapter 6].
1.3 Previous Work
The research presented in this thesis draws from previous work in systems engineering,
structural dynamics, integrated modeling, optimization and robust design. In this
section a review of the relevant work in these fields is presented.
Structural optimization is a well-developed field with a rich history. The advent
of the digital computer made optimizing structural elements in the design process
practical. Numerous examples can be found in the literature of sizing, shape and
topology optimization [64]. Sizing optimization is typically applied to a truss structure
and uses parameters such as member cross-sectional area and plate thickness as design
variables. In shape optimization the topology is fixed, but the structural boundaries
are allowed to change [56]. In topology optimization much less is known about the
structure and the search is for optimal material distributions to yield a preliminary
structural configuration [114, 73].
A large body of work exists on the application of sizing optimization to truss prob-
lems to minimize mass subject to static constraints such as maximum stress. Many
different optimization techniques have been applied to variations of this problem. The
reader is referred to Kirsch [66] for an overview of gradient methods and examples. It
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