Case 13.2: Velocity change of a subsonic aircraft

Verifies	Multidimensional table look-up
Gravitation	J2
Geodesy	WGS-84 rotating
Atmosphere	US 1976 STD
Winds	still air
Vehicle	F-16 with simple auto-pilot
Notes	Initially straight & level. t=5s, decrease commanded 5 KEAS

For the manuevering examples, the BlockDiagram from case 11 is modified to replace the controller with the auto-pilot configuration and generate the appropriate command signals.

from simupy import systems
from scipy import interpolate

from nesc_testcase_helper import plot_nesc_comparisons, plot_F16_controls, benchmark
from nesc_case11 import (
    int_opts,
    F16ControllerBlock,
    BD,
    opt_ctrl,
    dim_feedback,
    trimmed_KEAS,
)

keasCmdBlock = systems.SystemFromCallable(
    interpolate.make_interp_spline([0, 5], [trimmed_KEAS, trimmed_KEAS - 5.0], k=0),
    0,
    1,
)

BD.systems[-4] = keasCmdBlock
BD.systems[2] = F16ControllerBlock(*opt_ctrl, sasOn=True, apOn=True, event_t=5.)

with benchmark() as b:
    res = BD.simulate(20, integrator_options=int_opts)

Out:

time to simulate: 26.150 s

plot_nesc_comparisons(res, "13p2")
plot_F16_controls(res, "13p2")

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