Gravity v3 - FLOPS Gravity, Earth Radius values updated

aviary/api.py

@@ -55,13 +55,10 @@
 )
 from aviary.utils.options import list_options
 from aviary.constants import (
-    GRAV_ENGLISH_FLOPS,
     GRAV_ENGLISH_GASP,
     GRAV_ENGLISH_LBM,
-    GRAV_METRIC_FLOPS,
     GRAV_METRIC_GASP,
     PSLS_PSF,
-    RADIUS_EARTH_METRIC,
     RHO_SEA_LEVEL_ENGLISH,
     RHO_SEA_LEVEL_METRIC,
     TSLS_DEGR,

aviary/constants.py

@@ -16,6 +16,7 @@
 )  # Venus Global Reference Atmospheric Model (Venus-GRAM): User Guide, NASA/TM-20210022168
 
 RADIUS_EARTH = (6371009, 'm')  # Source: GRS80, mean earth radius (rounded to nearest meter)
+# convert_geopotential_altitude() is a python utility function that require RADIUS_EARTH to be specified in meters!
 
 RADIUS_MARS = (
     3386200,
@@ -28,9 +29,7 @@
 
 # GNS = 9.8236930  # grav_accel_at_surface_earth # TODO: Remove this from other parts of Aviary
 GRAV_METRIC_GASP = 9.81  # m/s^2
-GRAV_METRIC_FLOPS = 9.80665  # m/s^2
 GRAV_ENGLISH_GASP = 32.2  # ft/s^2
-GRAV_ENGLISH_FLOPS = 32.17399  # ft/s^2
 GRAV_ENGLISH_LBM = 1.0  # lbf/lbm
 # See issue 1169 for the value of RHO_SEA_LEVEL_ENGLISH
 RHO_SEA_LEVEL_ENGLISH = 0.0023769  # slug/ft^3
@@ -39,4 +38,3 @@
 PSLS_PSF = 2116.22
 # sea level standard temperature in deg R
 TSLS_DEGR = 518.67
-RADIUS_EARTH_METRIC = 6367533.0  # m (meridional)

aviary/mission/energy_state/ode/landing_eom.py

@@ -3,52 +3,36 @@
 import numpy as np
 import openmdao.api as om
 
-from aviary.constants import GRAV_METRIC_FLOPS as grav_metric
 from aviary.mission.energy_state.ode.takeoff_eom import (
     Accelerations,
     DistanceRates,
     FlightPathAngleRate,
     VelocityRate,
 )
 from aviary.utils.aviary_values import AviaryValues
-from aviary.variable_info.functions import add_aviary_input
+from aviary.variable_info.functions import add_aviary_input, add_aviary_option
 from aviary.variable_info.variables import Dynamic, Mission
 
 
 class FlareEOM(om.Group):
     """Define a group for calculating equations of motion from start of flare to touchdown."""
 
     def initialize(self):
-        options = self.options
-
-        options.declare('num_nodes', default=1, types=int, lower=0)
-
-        options.declare(
-            'aviary_options',
-            types=AviaryValues,
-            desc='collection of Aircraft/Mission specific options',
-        )
+        self.options.declare('num_nodes', default=1, types=int, lower=0)
 
     def setup(self):
-        options = self.options
-
-        nn = options['num_nodes']
-        aviary_options = options['aviary_options']
-
-        kwargs = {'num_nodes': nn, 'climbing': True}
+        nn = self.options['num_nodes']
 
         inputs = [Dynamic.Mission.FLIGHT_PATH_ANGLE, Dynamic.Mission.VELOCITY]
         outputs = [Dynamic.Mission.DISTANCE_RATE, Dynamic.Mission.ALTITUDE_RATE]
 
         self.add_subsystem(
             'distance_rates',
-            DistanceRates(**kwargs),
+            DistanceRates(num_nodes=nn, climbing=True),
             promotes_inputs=inputs,
             promotes_outputs=outputs,
         )
 
-        kwargs = {'num_nodes': nn, 'aviary_options': aviary_options}
-
         inputs = [
             Dynamic.Vehicle.MASS,
             Dynamic.Vehicle.LIFT,
@@ -61,7 +45,10 @@ def setup(self):
         outputs = ['forces_horizontal', 'forces_vertical']
 
         self.add_subsystem(
-            'sum_forces', FlareSumForces(**kwargs), promotes_inputs=inputs, promotes_outputs=outputs
+            'sum_forces',
+            FlareSumForces(num_nodes=nn),
+            promotes_inputs=inputs,
+            promotes_outputs=outputs,
         )
 
         inputs = ['forces_horizontal', 'forces_vertical', Dynamic.Vehicle.MASS]
@@ -120,7 +107,7 @@ def setup(self):
 
         self.add_subsystem(
             'glide_slope_forces',
-            GlideSlopeForces(**kwargs),
+            GlideSlopeForces(num_nodes=nn),
             promotes_inputs=inputs,
             promotes_outputs=outputs,
         )
@@ -145,27 +132,19 @@ class GlideSlopeForces(om.ExplicitComponent):
     """Define a component for calculating forces for evaluation of glide slope criteria."""
 
     def initialize(self):
-        options = self.options
+        self.options.declare('num_nodes', default=1, types=int, lower=0)
 
-        options.declare('num_nodes', default=1, types=int, lower=0)
-
-        options.declare(
-            'aviary_options',
-            types=AviaryValues,
-            desc='collection of Aircraft/Mission specific options',
-        )
+        add_aviary_option(self, Mission.GRAVITY, units='m/s**2')
+        add_aviary_option(self, Mission.Takeoff.ANGLE_OF_ATTACK_RUNWAY, units='rad')
+        add_aviary_option(self, Mission.Takeoff.THRUST_INCIDENCE, units='rad')
 
     def setup(self):
-        options = self.options
-
-        nn = options['num_nodes']
+        nn = self.options['num_nodes']
 
         add_aviary_input(self, Dynamic.Vehicle.MASS, shape=nn, units='kg')
         add_aviary_input(self, Dynamic.Vehicle.LIFT, shape=nn, units='N')
         add_aviary_input(self, Dynamic.Vehicle.DRAG, shape=nn, units='N')
-
         add_aviary_input(self, Dynamic.Vehicle.ANGLE_OF_ATTACK, shape=nn, units='rad')
-
         add_aviary_input(self, Dynamic.Mission.FLIGHT_PATH_ANGLE, shape=nn, units='rad')
 
         self.add_output(
@@ -184,21 +163,16 @@ def setup(self):
         )
 
     def setup_partials(self):
-        options = self.options
-
-        nn = options['num_nodes']
+        nn = self.options['num_nodes']
 
         rows_cols = np.arange(nn)
 
         self.declare_partials('*', '*', rows=rows_cols, cols=rows_cols)
 
     def compute(self, inputs, outputs, discrete_inputs=None, discrete_outputs=None):
-        options = self.options
-
-        aviary_options: AviaryValues = options['aviary_options']
-
-        alpha0 = aviary_options.get_val(Mission.Takeoff.ANGLE_OF_ATTACK_RUNWAY, 'rad')
-        t_inc = aviary_options.get_val(Mission.Takeoff.THRUST_INCIDENCE, 'rad')
+        alpha0 = self.options[Mission.Takeoff.ANGLE_OF_ATTACK_RUNWAY][0]
+        t_inc = self.options[Mission.Takeoff.THRUST_INCIDENCE][0]
+        grav_metric = self.options[Mission.GRAVITY][0]
 
         mass = inputs[Dynamic.Vehicle.MASS]
         lift = inputs[Dynamic.Vehicle.LIFT]
@@ -230,12 +204,9 @@ def compute(self, inputs, outputs, discrete_inputs=None, discrete_outputs=None):
         outputs['required_thrust'] = (f_h + f_v) / (2.0)
 
     def compute_partials(self, inputs, J, discrete_inputs=None):
-        options = self.options
-
-        aviary_options: AviaryValues = options['aviary_options']
-
-        alpha0 = aviary_options.get_val(Mission.Takeoff.ANGLE_OF_ATTACK_RUNWAY, 'rad')
-        t_inc = aviary_options.get_val(Mission.Takeoff.THRUST_INCIDENCE, 'rad')
+        alpha0 = self.options[Mission.Takeoff.ANGLE_OF_ATTACK_RUNWAY][0]
+        t_inc = self.options[Mission.Takeoff.THRUST_INCIDENCE][0]
+        grav_metric = self.options[Mission.GRAVITY][0]
 
         mass = inputs[Dynamic.Vehicle.MASS]
         lift = inputs[Dynamic.Vehicle.LIFT]
@@ -302,28 +273,20 @@ class FlareSumForces(om.ExplicitComponent):
     """
 
     def initialize(self):
-        options = self.options
+        self.options.declare('num_nodes', default=1, types=int, lower=0)
 
-        options.declare('num_nodes', default=1, types=int, lower=0)
-
-        options.declare(
-            'aviary_options',
-            types=AviaryValues,
-            desc='collection of Aircraft/Mission specific options',
-        )
+        add_aviary_option(self, Mission.GRAVITY, units='m/s**2')
+        add_aviary_option(self, Mission.Takeoff.ANGLE_OF_ATTACK_RUNWAY, units='rad')
+        add_aviary_option(self, Mission.Takeoff.THRUST_INCIDENCE, units='rad')
 
     def setup(self):
-        options = self.options
-
-        nn = options['num_nodes']
+        nn = self.options['num_nodes']
 
         add_aviary_input(self, Dynamic.Vehicle.MASS, shape=nn, units='kg')
         add_aviary_input(self, Dynamic.Vehicle.LIFT, shape=nn, units='N')
         add_aviary_input(self, Dynamic.Vehicle.Propulsion.THRUST_TOTAL, shape=nn, units='N')
         add_aviary_input(self, Dynamic.Vehicle.DRAG, shape=nn, units='N')
-
         add_aviary_input(self, Dynamic.Vehicle.ANGLE_OF_ATTACK, shape=nn, units='rad')
-
         add_aviary_input(self, Dynamic.Mission.FLIGHT_PATH_ANGLE, shape=nn, units='rad')
 
         self.add_output(
@@ -341,9 +304,9 @@ def setup(self):
         )
 
     def setup_partials(self):
-        options = self.options
+        nn = self.options['num_nodes']
 
-        nn = options['num_nodes']
+        grav_metric = self.options[Mission.GRAVITY][0]
 
         rows_cols = np.arange(nn)
 
@@ -368,12 +331,9 @@ def setup_partials(self):
         self.declare_partials('*', wrt, rows=rows_cols, cols=rows_cols)
 
     def compute(self, inputs, outputs, discrete_inputs=None, discrete_outputs=None):
-        options = self.options
-
-        aviary_options: AviaryValues = options['aviary_options']
-
-        alpha0 = aviary_options.get_val(Mission.Takeoff.ANGLE_OF_ATTACK_RUNWAY, 'rad')
-        t_inc = aviary_options.get_val(Mission.Takeoff.THRUST_INCIDENCE, 'rad')
+        alpha0 = self.options[Mission.Takeoff.ANGLE_OF_ATTACK_RUNWAY][0]
+        t_inc = self.options[Mission.Takeoff.THRUST_INCIDENCE][0]
+        grav_metric = self.options[Mission.GRAVITY][0]
 
         mass = inputs[Dynamic.Vehicle.MASS]
         lift = inputs[Dynamic.Vehicle.LIFT]
@@ -406,12 +366,8 @@ def compute(self, inputs, outputs, discrete_inputs=None, discrete_outputs=None):
         outputs['forces_vertical'] = f_v
 
     def compute_partials(self, inputs, J, discrete_inputs=None):
-        options = self.options
-
-        aviary_options: AviaryValues = options['aviary_options']
-
-        alpha0 = aviary_options.get_val(Mission.Takeoff.ANGLE_OF_ATTACK_RUNWAY, 'rad')
-        t_inc = aviary_options.get_val(Mission.Takeoff.THRUST_INCIDENCE, 'rad')
+        alpha0 = self.options[Mission.Takeoff.ANGLE_OF_ATTACK_RUNWAY][0]
+        t_inc = self.options[Mission.Takeoff.THRUST_INCIDENCE][0]
 
         lift = inputs[Dynamic.Vehicle.LIFT]
         thrust = inputs[Dynamic.Vehicle.Propulsion.THRUST_TOTAL]
@@ -470,10 +426,10 @@ def initialize(self):
             desc='current friction coefficient, either rolling friction or breaking friction',
         )
 
-    def setup(self):
-        options = self.options
+        add_aviary_option(self, Mission.GRAVITY, units='m/s**2')
 
-        nn = options['num_nodes']
+    def setup(self):
+        nn = self.options['num_nodes']
 
         add_aviary_input(self, Dynamic.Vehicle.MASS, shape=nn, units='kg')
         add_aviary_input(self, Dynamic.Vehicle.LIFT, shape=nn, units='N')
@@ -495,9 +451,9 @@ def setup(self):
         )
 
     def setup_partials(self):
-        options = self.options
+        nn = self.options['num_nodes']
 
-        nn = options['num_nodes']
+        grav_metric = self.options[Mission.GRAVITY][0]
 
         rows_cols = np.arange(nn)
 
@@ -544,6 +500,8 @@ def compute(self, inputs, outputs, discrete_inputs=None, discrete_outputs=None):
         nn = options['num_nodes']
         friction_coefficient = options['friction_coefficient']
 
+        grav_metric = self.options[Mission.GRAVITY][0]
+
         mass = inputs[Dynamic.Vehicle.MASS]
         lift = inputs[Dynamic.Vehicle.LIFT]
         thrust = inputs[Dynamic.Vehicle.Propulsion.THRUST_TOTAL]
@@ -567,6 +525,8 @@ def compute_partials(self, inputs, J, discrete_inputs=None):
         nn = options['num_nodes']
         friction_coefficient = options['friction_coefficient']
 
+        grav_metric = self.options[Mission.GRAVITY][0]
+
         mass = inputs[Dynamic.Vehicle.MASS]
         lift = inputs[Dynamic.Vehicle.LIFT]
 

aviary/mission/energy_state/ode/landing_ode.py

@@ -29,9 +29,7 @@ class FlareODE(_BaseODE):
     """Define the ODE for the flare phase of landing."""
 
     def setup(self):
-        options = self.options
-
-        nn = options['num_nodes']
+        nn = self.options['num_nodes']
         self.add_subsystem(name='atmosphere', subsys=Atmosphere(num_nodes=nn), promotes=['*'])
 
         # NOTE: the following are potentially significant differences in implementation
@@ -55,11 +53,9 @@ def setup(self):
 
         self.add_subsystems()
 
-        kwargs = {'num_nodes': nn, 'aviary_options': options['aviary_options']}
-
         self.add_subsystem(
             'landing_eom',
-            FlareEOM(**kwargs),
+            FlareEOM(num_nodes=nn),
             promotes_inputs=[
                 Dynamic.Mission.FLIGHT_PATH_ANGLE,
                 Dynamic.Mission.VELOCITY,

aviary/mission/energy_state/ode/required_thrust.py

@@ -1,9 +1,8 @@
 import numpy as np
 import openmdao.api as om
-from aviary.variable_info.functions import add_aviary_input
+from aviary.variable_info.functions import add_aviary_input, add_aviary_option
 
-from aviary.constants import GRAV_METRIC_FLOPS as gravity
-from aviary.variable_info.variables import Dynamic
+from aviary.variable_info.variables import Dynamic, Mission
 
 
 class RequiredThrust(om.ExplicitComponent):
@@ -14,6 +13,7 @@ class RequiredThrust(om.ExplicitComponent):
 
     def initialize(self):
         self.options.declare('num_nodes', types=int)
+        add_aviary_option(self, Mission.GRAVITY, units='m/s**2')
 
     def setup(self):
         nn = self.options['num_nodes']
@@ -49,28 +49,30 @@ def setup(self):
         self.declare_partials('thrust_required', Dynamic.Vehicle.MASS, rows=ar, cols=ar)
 
     def compute(self, inputs, outputs):
+        grav_metric = self.options[Mission.GRAVITY][0]
         drag = inputs[Dynamic.Vehicle.DRAG]
         altitude_rate = inputs[Dynamic.Mission.ALTITUDE_RATE]
         velocity = inputs[Dynamic.Mission.VELOCITY]
         velocity_rate = inputs[Dynamic.Mission.VELOCITY_RATE]
         mass = inputs[Dynamic.Vehicle.MASS]
 
-        thrust_required = drag + (altitude_rate * gravity / velocity + velocity_rate) * mass
+        thrust_required = drag + (altitude_rate * grav_metric / velocity + velocity_rate) * mass
 
         outputs['thrust_required'] = thrust_required
 
     def compute_partials(self, inputs, partials):
+        grav_metric = self.options[Mission.GRAVITY][0]
         altitude_rate = inputs[Dynamic.Mission.ALTITUDE_RATE]
         velocity = inputs[Dynamic.Mission.VELOCITY]
         velocity_rate = inputs[Dynamic.Mission.VELOCITY_RATE]
         mass = inputs[Dynamic.Vehicle.MASS]
 
         partials['thrust_required', Dynamic.Vehicle.DRAG] = 1.0
-        partials['thrust_required', Dynamic.Mission.ALTITUDE_RATE] = gravity / velocity * mass
+        partials['thrust_required', Dynamic.Mission.ALTITUDE_RATE] = grav_metric / velocity * mass
         partials['thrust_required', Dynamic.Mission.VELOCITY] = (
-            -altitude_rate * gravity / velocity**2 * mass
+            -altitude_rate * grav_metric / velocity**2 * mass
         )
         partials['thrust_required', Dynamic.Mission.VELOCITY_RATE] = mass
         partials['thrust_required', Dynamic.Vehicle.MASS] = (
-            altitude_rate * gravity / velocity + velocity_rate
+            altitude_rate * grav_metric / velocity + velocity_rate
         )