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BUG: Allow multiple sets of stochastic fins by WilliamArmst · Pull Request #737 · RocketPy-Team/RocketPy

If there is a rocket with 2 sets of fins and you try to make them stochastic, the function that is fixed in the code will throw because it only checks the first set of fins. This makes it impossible to add 2 sets of fins.

from rocketpy import TrapezoidalFins, Rocket, StochasticTrapezoidalFins, StochasticRocket

# apply percent standard deviation to components
percentStdDeviation = 0.1

testRocket = Rocket( # All of the data is incorrect
    radius=0.1,
    mass=1,
    inertia=(6.321, 6.321, 0.034),
    power_off_drag= "powerOffDragCurve.csv",
    power_on_drag= "powerOnDragCurve.csv",
    center_of_mass_without_motor=0.5,
    coordinate_system_orientation="tail_to_nose",
)
fin_set_1 = testRocket.add_trapezoidal_fins(
    n=4,
    root_chord=0.203,
    tip_chord=0.0381,
    span=0.102,
    sweep_length=0.21,
    position=-0.015,
    cant_angle=0.5,
    airfoil=("airfoil_example.csv","radians"), # insert a .csv file for the side profile of the fin
)
fin_set_2 = testRocket.add_trapezoidal_fins(
    n = 4,
    root_chord=0.203,
    tip_chord=0.0381,
    span=0.102,
    sweep_length=0.21,
    position=-1.945,
    cant_angle=0.5,
    airfoil=("airfoil_example.csv","radians"), # insert a .csv file for the side profile of the fin
)
fin_set_3 = TrapezoidalFins(
    n = 4,
    root_chord=0.203,
    tip_chord=0.0381,
    span=0.102,
    sweep_length=0.21,
    cant_angle=0.5,
    rocket_radius=0.1,
    airfoil=("airfoil_example.csv","radians"), # insert a .csv file for the side profile of the fin
)

stochastic_fin_set_1_object = StochasticTrapezoidalFins(
    trapezoidal_fins=fin_set_1,
    root_chord=percentStdDeviation * fin_set_1.root_chord,
    tip_chord=percentStdDeviation * fin_set_1.tip_chord,
    span=percentStdDeviation * fin_set_1.span,
    sweep_length=percentStdDeviation * fin_set_1.sweep_length,
    cant_angle=0.01, # +- 0.01deg
)
stochastic_fin_set_2_object = StochasticTrapezoidalFins(
    trapezoidal_fins=fin_set_2,
    root_chord=percentStdDeviation * fin_set_2.root_chord,
    tip_chord=percentStdDeviation * fin_set_2.tip_chord,
    span=percentStdDeviation * fin_set_2.span,
    sweep_length=percentStdDeviation * fin_set_2.sweep_length,
    cant_angle=0.01, # +- 0.01deg
)

stochastic_testRocket = StochasticRocket(
    rocket=testRocket,
    radius=0.1 * testRocket.radius,
    mass=0.1 * testRocket.mass,
    center_of_mass_without_motor=0.1 * testRocket.center_of_mass_without_motor,
)

stochastic_fin_set_sustainer_Event1 = stochastic_testRocket.add_trapezoidal_fins(
   fins=stochastic_fin_set_1_object,
   position=0.01, # +-1cm
)

stochastic_fin_set_booster_Event1 = stochastic_testRocket.add_trapezoidal_fins(
    fins=stochastic_fin_set_2_object,
    position=0.01, # +-1cm
)

testRocket.draw()

I also tested adding a stochastic fin that actually wasn't a part of the rocket, and it still catches that error (replace one of the trapezoidal_fins= with fin_set_3 to see this work)

Behaves as expected.

I thought I figured out the git stuff but ig I didn't. Oh well. I am allowed to not know how to use git because I am fixing your bugs.