Developement Of A Batch Mode For Conduit And Its ... - Cal Poly

5 Lessons Learned
Four significant lessons were learned in the course of this thesis. Specifically, the
lessons deal with the running of problems in Batch Mode:
1. It was learned that terminating unused input and output blocks can significantly
improve simulation times. In a Batch Mode problem with a large number of cases,
this small gain in run time can result in large time savings.
2. If interpolation is used to create cases between two known models, then the
interpolation method must be chosen such that the stability derivatives vary smoothly
in a realistic manner. If not, then the results of resulting gain schedules can be
inaccurate or have discontinuities.
3. Time specs must be watched carefully over the range of varying cases.
As demonstrated with the damping ratio spec, time specs that require a signal of a
specific form can return invalid results when the signal is not of this form. Since time
signals can vary to many different forms, it is best to avoid time specs in Batch
Problems. However, if they must be used, they should be checked at several different
cases to ensure the time signal is of the appropriate form for the spec. If not, then the
spec must be modified to accommodate for the discrepancies.
4. The cases must be well constrained over the entire range of cases. In the case of the
SH-2G problem, it was found that the original Attitude Hold spec was not sufficient
to constrain the problem in the mid-range velocities, and the system went open loop.
As a result, the gains in this region were arbitrary, and the gain schedules weren’t
smooth. In addition to the cases being well constrained, they must also be similarly
constrained. In other words, the critical constraint should be the same for all cases. If
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