CIFER®-MATLAB Interfaces: Development and ... - Cal Poly

Chapter 4: Validation and Application
In order to confirm that the new code would accurately move information between CIFER ® and
MATLAB, many tests were conducted. In the early stages of the code development, various
sample cases provided with CIFER ®
installations, such as the XVLATSWP case mentioned
previously, were used. Also at this stage, a simple mass-spring-damper system was modeled as a
potential example to new users of CIFER ® . Once the codes were more developed, more
complicated validations were employed. The first was a closed-loop investigation of a UH-60
simulation, and the second was a series of data consistency checks and cutoff frequency analysis
on the Shadow 200 Tactical Unmanned Aerial Vehicle (TUAV) 6 .
4.1 Sample CIFER Cases
CIFER ® installations come with a series of time histories for the XV-15, and its documentation 5
uses related sample cases as examples. New users of CIFER ® typically learn the interface by
working through the set-up of these cases. Thus, the cases made excellent initial comparisons to
determine if the MATLAB interface was working correctly. At this stage, the analysis was
essentially creating plots of cases set up and run from CIFER ® and cases set up and run from
MATLAB. The only major problem found was the numeric precision error discussed in Chapter
3. Examples of the scripts used to set up one example case can be found in Appendix I.
A series of example comparisons for the lateral sweep are shown in Figure 4.1. The aileron input
is plotted against roll rate, yaw rate, lateral acceleration, and vertical velocity perturbation. The
important aspect of the figure is that the plots comparing the results set up and run from
MATLAB, to those set up and run from CIFER ® match. Additional plots and analysis for the XV-
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