TST: adds prometheus apogee acceptance test

Author: Gui-FernandesBR

tests/acceptance/test_prometheus_rocket.py

@@ -0,0 +1,70 @@
+from rocketpy import Flight
+from rocketpy.simulation.flight_data_importer import FlightDataImporter
+
+
+def test_prometheus_rocket_data_asserts_acceptance(
+    environment_spaceport_america_2023, prometheus_rocket
+):
+    """Tests the Prometheus rocket flight data against acceptance criteria.
+
+    This function simulates a rocket flight using the given environment and
+    rocket parameters, then compares the simulated apogee with real flight data
+    to ensure the relative error is within acceptable thresholds.
+
+    Parameters
+    ----------
+    environment_spaceport_america_2023 : Environment
+        An environment configuration for Spaceport America in 2023.
+    prometheus_rocket : Rocket
+        The Prometheus rocket configuration.
+
+    Raises
+    ------
+    AssertionError
+        If the relative error between the simulated apogee and the real apogee
+        exceeds the threshold.
+    """
+    # Define relative error threshold (defined manually based on data)
+    apogee_threshold = 7.5 / 100
+
+    # Simulate the flight
+    test_flight = Flight(
+        rocket=prometheus_rocket,
+        environment=environment_spaceport_america_2023,
+        inclination=80,
+        heading=75,
+        rail_length=5.18,
+    )
+
+    # Read the flight data
+    columns_map = {
+        "time": "time",
+        "altitude": "z",
+        "height": "altitude",
+        "acceleration": "acceleration",
+        "pressure": "pressure",
+        "accel_x": "ax",
+        "accel_y": "ay",
+        "accel_z": "az",
+        "latitude": "latitude",
+        "longitude": "longitude",
+    }
+
+    altimeter_data = FlightDataImporter(
+        name="Telemetry Mega",
+        paths="data/prometheus/2022-06-24-serial-6583-flight-0003-TeleMega.csv",
+        columns_map=columns_map,
+        units=None,
+        interpolation="linear",
+        extrapolation="zero",
+        delimiter=",",
+        encoding="utf-8",
+    )
+
+    # Calculate errors and assert values
+    real_apogee = altimeter_data.altitude.max
+    rocketpy_apogee = test_flight.apogee - test_flight.env.elevation
+    a_error = abs(real_apogee - rocketpy_apogee)
+    r_error = a_error / real_apogee
+
+    assert r_error < apogee_threshold, f"Apogee relative error is {r_error*100:.2f}%"

tests/fixtures/environment/environment_fixtures.py

@@ -71,3 +71,30 @@ def env_analysis():
     )
 
     return env_analysis
+
+
+@pytest.fixture
+def environment_spaceport_america_2023():
+    """Creates an Environment object for Spaceport America with a 2023 launch
+    conditions.
+
+    Returns
+    -------
+    rocketpy.Environment
+        Environment object configured for Spaceport America in 2023.
+    """
+    env = Environment(
+        latitude=32.939377,
+        longitude=-106.911986,
+        elevation=1401,
+    )
+    env.set_date(date=(2023, 6, 24, 9), timezone="America/Denver")
+
+    env.set_atmospheric_model(
+        type="Reanalysis",
+        file="data/weather/spaceport_america_pressure_levels_2023_hourly.nc",
+        dictionary="ECMWF",
+    )
+
+    env.max_expected_height = 6000
+    return env

tests/fixtures/motor/generic_motor_fixtures.py

@@ -28,3 +28,27 @@ def generic_motor():
     )
 
     return motor
+
+
+@pytest.fixture
+def generic_motor_cesaroni_M1520():
+    """Defines a Cesaroni M1520 motor for the Prometheus rocket using the
+    GenericMotor class.
+
+    Returns
+    -------
+    GenericMotor
+        The Cesaroni M1520 motor for the Prometheus rocket.
+    """
+    return GenericMotor(
+        # burn specs: https://www.thrustcurve.org/simfiles/5f4294d20002e900000006b1/
+        thrust_source="data/motors/cesaroni/Cesaroni_7579M1520-P.eng",
+        burn_time=4.897,
+        propellant_initial_mass=3.737,
+        dry_mass=2.981,
+        # casing specs: Pro98 3G Gen2 casing
+        chamber_radius=0.064,
+        chamber_height=0.548,
+        chamber_position=0.274,
+        nozzle_radius=0.027,
+    )

tests/fixtures/rockets/rocket_fixtures.py

@@ -1,3 +1,4 @@
+import numpy as np
 import pytest
 
 from rocketpy import Rocket
@@ -276,3 +277,81 @@ def dimensionless_calisto(kg, m, dimensionless_cesaroni_m1670):
     )
     example_rocket.add_motor(dimensionless_cesaroni_m1670, position=(-1.373) * m)
     return example_rocket
+
+
+@pytest.fixture
+def prometheus_rocket(generic_motor_cesaroni_M1520):
+    """Create a simple object of the Rocket class to be used in the tests. This
+    is the Prometheus rocket, a rocket documented in the Flight Examples section
+    of the RocketPy documentation.
+
+    Parameters
+    ----------
+    generic_motor_cesaroni_M1520 : GenericMotor
+        An object of the GenericMotor class. This is a pytest fixture too.
+    """
+
+    def prometheus_cd_at_ma(mach):
+        """Gives the drag coefficient of the rocket at a given mach number."""
+        if mach <= 0.15:
+            return 0.422
+        elif mach <= 0.45:
+            return 0.422 + (mach - 0.15) * (0.38 - 0.422) / (0.45 - 0.15)
+        elif mach <= 0.77:
+            return 0.38 + (mach - 0.45) * (0.32 - 0.38) / (0.77 - 0.45)
+        elif mach <= 0.82:
+            return 0.32 + (mach - 0.77) * (0.3 - 0.32) / (0.82 - 0.77)
+        elif mach <= 0.88:
+            return 0.3 + (mach - 0.82) * (0.3 - 0.3) / (0.88 - 0.82)
+        elif mach <= 0.94:
+            return 0.3 + (mach - 0.88) * (0.32 - 0.3) / (0.94 - 0.88)
+        elif mach <= 0.99:
+            return 0.32 + (mach - 0.94) * (0.37 - 0.32) / (0.99 - 0.94)
+        elif mach <= 1.04:
+            return 0.37 + (mach - 0.99) * (0.44 - 0.37) / (1.04 - 0.99)
+        elif mach <= 1.24:
+            return 0.44 + (mach - 1.04) * (0.43 - 0.44) / (1.24 - 1.04)
+        elif mach <= 1.33:
+            return 0.43 + (mach - 1.24) * (0.42 - 0.43) / (1.33 - 1.24)
+        elif mach <= 1.49:
+            return 0.42 + (mach - 1.33) * (0.39 - 0.42) / (1.49 - 1.33)
+        else:
+            return 0.39
+
+    prometheus = Rocket(
+        radius=0.06985,  # 5.5" diameter circle
+        mass=13.93,
+        inertia=(
+            4.87,
+            4.87,
+            0.05,
+        ),
+        power_off_drag=prometheus_cd_at_ma,
+        power_on_drag=lambda x: prometheus_cd_at_ma(x) * 1.02,  # 5% increase in drag
+        center_of_mass_without_motor=0.9549,
+        coordinate_system_orientation="tail_to_nose",
+    )
+
+    prometheus.set_rail_buttons(0.69, 0.21, 60)
+
+    prometheus.add_motor(motor=generic_motor_cesaroni_M1520, position=0)
+    nose_cone = prometheus.add_nose(length=0.742, kind="Von Karman", position=2.229)
+    fin_set = prometheus.add_trapezoidal_fins(
+        n=3,
+        span=0.13,
+        root_chord=0.268,
+        tip_chord=0.136,
+        position=0.273,
+        sweep_length=0.066,
+    )
+    drogue_chute = prometheus.add_parachute(
+        "Drogue",
+        cd_s=1.6 * np.pi * 0.3048**2,  # Cd = 1.6, D_chute = 24 in
+        trigger="apogee",
+    )
+    main_chute = prometheus.add_parachute(
+        "Main",
+        cd_s=2.2 * np.pi * 0.9144**2,  # Cd = 2.2, D_chute = 72 in
+        trigger=457.2,  # 1500 ft
+    )
+    return prometheus