The maneuvers of interest are doublets ranging in magnitude and centered
around a trim condition. Therefore, the assumption of linearity is reasonable since the
maneuvers are about trim. For the approximation, the rates which are considered are
roll and yaw rate because they are of most interest for maneuvers such as doublets.
The accelerometers were considered but the data was very noisy, therefore, not
allowing for accurate approximations to be made.
The simulated and measured values of roll rate and yaw rate are shown in
Figure 5-12.
200 200
150i 150
100 100
50 50
0 0
4 -50 \- -50
-100 -100
150 150
-200 -------------------- 200--------------------
0 05 1 15 22 25 0 05 1 1 5 2 25
Time(sec) Time(sec)
Figure 5-12: Simulated (- ) and Actual (-) Roll Rate(left) and Yaw Rate(right)
Responses to Morphing Doublet
The simulated responses show good correlation with the actual data. The model is
thus considered a reasonable representation of the aircraft dynamics as it is excited by
the doublet. The existence of such a model is important for future design of autopilot
controllers but it is also valuable for interpreting the morphing.
When using the ARX simulation in Matlab, a linear approximation could not be
made on the maneuvers which were not centered around trim. Therefore, not only are
maneuvers around trim desired for a linear approximation, but they are also necessary
in order for the simulation to be done.
The model which will be used was chosen because it produced the closest match
to the maneuver as compared to four other doublets. The maneuvers compared were
from the same data set, but the one that was chosen resulted in a closer match due to