Chapter 5 Robust Performance Tailoring with Tuning - SSL - MIT

problem. The optimizations are run with both SQP and SA search techniques to
produce robust optimal designs. The performance of the optimization techniques are
compared, and it is found that the SA design is a good initial guess for SQP, enabling
quick convergence to the optimal design for this particular problem. It is also found
that the anti-optimization cost function is the most conservative of the three chosen
and produces the design with the lowest worst-case performance variance.
The RPT AO and MM designs are compared to the PT design, and it is shown
that the RPT designs achieve greater robustness by tailoring the truss such that the
inner segments are larger than the outer segments resulting in an increase in the nat-
ural frequency of the first bending mode. The PT and RPT designs are compared
over a range of uncertainty levels and the concept of design regimes is introduced.
PT designs are only adequate in the cases of relaxed performance requirements and
low uncertainty levels. RPT designs cover much more of the design space and can
accommodate greater levels of uncertainty than the PT designs at equivalent perfor-
mance requirements. However, even the RPT methodology is not adequate in the
high-performance, high-uncertainty regime.
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