Skip to content

StochasticNoseCone does not support "powerseries" nose cones #838

@cazzopardi

Description

@cazzopardi

Describe the bug

The StochasticNoseCone class does not support nose cones of kind 'powerseries' as the constructor does not accept a power parameter.

To Reproduce

Attempt to call simulate() on any Monte Carlo simulation object that was initialised with a nose cone of kind "powerseries". The following is an example modified from the documentation:

import datetime

from rocketpy import Environment, Flight, Function, MonteCarlo, Rocket, SolidMotor
from rocketpy.stochastic import (
    StochasticEnvironment,
    StochasticFlight,
    StochasticNoseCone,
    StochasticParachute,
    StochasticRailButtons,
    StochasticRocket,
    StochasticSolidMotor,
    StochasticTail,
    StochasticTrapezoidalFins,
)
# Environment
env = Environment(latitude=39.389700, longitude=-8.288964, elevation=113)
tomorrow = datetime.date.today() + datetime.timedelta(days=1)
env.set_date((tomorrow.year, tomorrow.month, tomorrow.day, 12))
env.set_atmospheric_model(type="Ensemble", file="GEFS")

# Motor
motor = SolidMotor(
    thrust_source="Data/K1102.eng",
    dry_mass=1.815,
    dry_inertia=(0.125, 0.125, 0.002),
    nozzle_radius=33 / 1000,
    grain_number=5,
    grain_density=1815,
    grain_outer_radius=33 / 1000,
    grain_initial_inner_radius=15 / 1000,
    grain_initial_height=120 / 1000,
    grain_separation=5 / 1000,
    grains_center_of_mass_position=0.397,
    center_of_dry_mass_position=0.317,
    nozzle_position=0,
    burn_time=3.9,
    throat_radius=11 / 1000,
    coordinate_system_orientation="nozzle_to_combustion_chamber",
)
print(f"Total Impulse of the Solid Motor: {motor.total_impulse} Ns")

drag_curve = Function("Data/cleaned_drag.csv")
# Rocket
rocket = Rocket(
    radius=127 / 2000,
    mass=14.426,
    inertia=(6.321, 6.321, 0.034),
    power_off_drag=drag_curve,
    power_on_drag=drag_curve,
    center_of_mass_without_motor=0,
    coordinate_system_orientation="tail_to_nose",
)

rail_buttons = rocket.set_rail_buttons(
    upper_button_position=0.0818,
    lower_button_position=-0.618,
    angular_position=45,
)

rocket.add_motor(motor, position=-1.255)

nose_cone = rocket.add_nose(length=0.55829, kind="powerseries", power=0.7, position=1.278)

fin_set = rocket.add_trapezoidal_fins(
    n=4,
    root_chord=0.120,
    tip_chord=0.060,
    span=0.110,
    position=-1.04956,
    cant_angle=0.5,
)

tail = rocket.add_tail(
    top_radius=0.0635, bottom_radius=0.0435, length=0.060, position=-1.194656
)
Main = rocket.add_parachute(
    "Main",
    cd_s=10.0,
    trigger=800,
    sampling_rate=105,
    lag=1.5,
    noise=(0, 8.3, 0.5),
)

Drogue = rocket.add_parachute(
    "Drogue",
    cd_s=1.0,
    trigger="apogee",
    sampling_rate=105,
    lag=1.5,
    noise=(0, 8.3, 0.5),
)

# Flight
test_flight = Flight(
    rocket=rocket,
    environment=env,
    rail_length=5,
    inclination=84,
    heading=133,
)
stochastic_env = StochasticEnvironment(
    environment=env,
    ensemble_member=list(range(env.num_ensemble_members)),
)

stochastic_env.visualize_attributes()
wind_speed_at_1000m = []
for i in range(5):
    rnd_env = stochastic_env.create_object()
    wind_speed_at_1000m.append(rnd_env.wind_velocity_x(1000))

print(wind_speed_at_1000m)
stochastic_motor = StochasticSolidMotor(
    solid_motor=motor,
    burn_start_time=(0, 0.1, "binomial"),
    grains_center_of_mass_position=0.001,
    grain_density=50,
    grain_separation=1 / 1000,
    grain_initial_height=1 / 1000,
    grain_initial_inner_radius=0.375 / 1000,
    grain_outer_radius=0.375 / 1000,
    total_impulse=(6500, 1000),
    throat_radius=0.5 / 1000,
    nozzle_radius=0.5 / 1000,
    nozzle_position=0.001,
)
stochastic_motor.visualize_attributes()
total_impulse = []
for i in range(5):
    rnd_motor = stochastic_motor.create_object()
    total_impulse.append(rnd_motor.total_impulse)

print(total_impulse)
stochastic_rocket = StochasticRocket(
    rocket=rocket,
    radius=0.0127 / 2000,
    mass=(15.426, 0.5, "normal"),
    inertia_11=(6.321, 0),
    inertia_22=0.01,
    inertia_33=0.01,
    center_of_mass_without_motor=0,
)
stochastic_rocket.visualize_attributes()

stochastic_nose_cone = StochasticNoseCone(
    nosecone=nose_cone,
    length=0.001,
)

stochastic_fin_set = StochasticTrapezoidalFins(
    trapezoidal_fins=fin_set,
    root_chord=0.0005,
    tip_chord=0.0005,
    span=0.0005,
)

stochastic_tail = StochasticTail(
    tail=tail,
    top_radius=0.001,
    bottom_radius=0.001,
    length=0.001,
)

stochastic_rail_buttons = StochasticRailButtons(
    rail_buttons=rail_buttons, buttons_distance=0.001
)

stochastic_main = StochasticParachute(
    parachute=Main,
    cd_s=0.1,
    lag=0.1,
)

stochastic_drogue = StochasticParachute(
    parachute=Drogue,
    cd_s=0.07,
    lag=0.2,
)
stochastic_rocket.add_motor(stochastic_motor, position=0.001)
stochastic_rocket.add_nose(stochastic_nose_cone, position=(1.134, 0.001))
stochastic_rocket.add_trapezoidal_fins(stochastic_fin_set, position=(0.001, "normal"))
stochastic_rocket.add_tail(stochastic_tail)
stochastic_rocket.set_rail_buttons(
    stochastic_rail_buttons, lower_button_position=(0.001, "normal")
)
stochastic_rocket.add_parachute(stochastic_main)
stochastic_rocket.add_parachute(stochastic_drogue)

stochastic_flight = StochasticFlight(
    flight=test_flight,
    inclination=(84.7, 1),  # mean= 84.7, std=1
    heading=(53, 2),  # mean= 53, std=2
)
test_dispersion = MonteCarlo(
    filename="monte_carlo_analysis_outputs/monte_carlo_class_example",
    environment=stochastic_env,
    rocket=stochastic_rocket,
    flight=stochastic_flight,
)
test_dispersion.simulate(
    number_of_simulations=10,
    append=False,
    include_function_data=False,
    parallel=False,
    n_workers=4,
)

Expected behavior

Simulation should run normally. Currently, this results in:

ValueError: Parameter 'power' cannot be None when using a nose cone kind 'powerseries'.

Metadata

Metadata

Assignees

No one assigned

    Labels

    No labels
    No labels

    Type

    No type

    Projects

    Milestone

    No milestone

    Relationships

    None yet

    Development

    No branches or pull requests

    Issue actions