Chapter 5 Robust Performance Tailoring with Tuning - SSL - MIT

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Figure 3-1: Uncertainty propagation results on PT optimized design: histogram - MC
results, (- -) worst-case vertex search, ∆ = 10%.
Table 3.2: Uncertainty propagation results: PT design.
RMS Young’s Modulus [GPa]
[µm] E1 E2
nominal 100.53 72.0 72.0
WC vertex 1355.5 64.8 79.2
WC Monte Carlo 1315.9 64.85 78.73
performance value from the vertex search. The fact that all of the Monte Carlo
performance predictions are below this value is a good indication that the convexity
assumption is valid in this case. The values of nominal and worst case RMS, along
with the uncertainty parameter values, are listed in Table 3.2. Note that the worst-
case performance occurs at an asymmetric configuration when E1 and E2 are at the
lower and upper limits, respectively.
The frequency response functions (FRF) from disturbance forces and torques to
the output are presented in Figures 3-2(a) through 3-2(c). The transfer functions for
the PT configuration at nominal uncertainty values are depicted with a solid line,
while those for the worst-case uncertainty configuration obtained through the vertex
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