# RCAIDE/Library/Methods/Aerodynamics/Vortex_Lattice_Method/build_VLM_surrogates.py
#
# ----------------------------------------------------------------------------------------------------------------------
# IMPORT
# ----------------------------------------------------------------------------------------------------------------------
# RCAIDE imports
from RCAIDE.Framework.Core import Data
# package imports
from scipy.interpolate import RegularGridInterpolator
from scipy import interpolate
# ----------------------------------------------------------------------------------------------------------------------
# Vortex_Lattice
# ----------------------------------------------------------------------------------------------------------------------
[docs]
def build_VLM_surrogates(aerodynamics, vehicle):
"""
Build surrogate models for aerodynamic coefficients using VLM analysis results.
This function creates interpolation-based surrogate models for various aerodynamic
coefficients across different flight regimes (subsonic, transonic, supersonic).
Parameters
----------
aerodynamics : Data
VLM analysis data structure containing training data and vehicle information
- training : Data
Training data with aerodynamic coefficients at different conditions
- vehicle : Data
Vehicle configuration data
- surrogates : Data
Container to store the created surrogate models
Returns
-------
None
Results are stored in the aerodynamics.surrogates data structure
Notes
-----
The function creates separate surrogate models for subsonic, transonic, and
supersonic regimes. For supersonic and transonic regimes, surrogates are only
built if sufficient data points are available (more than 2 Mach points).
The surrogate models use interpolation to predict aerodynamic coefficients
at arbitrary flight conditions within the training data range.
**Theory**
The function uses regular grid interpolation for 2D data (e.g., coefficient vs
angle of attack and Mach number) and 1D interpolation for stability derivatives.
**Related Functions:**
build_surrogate : Creates individual surrogate models for a specific flight regime
no_surrogate : Creates placeholder surrogate structures when data is insufficient
"""
surrogates = aerodynamics.surrogates
training = aerodynamics.training
Mach = aerodynamics.training.Mach
sub_len = int(sum(Mach<1.))
sup_Mach = Mach[sub_len:]
surrogates.subsonic = build_surrogate(aerodynamics, training.subsonic, vehicle)
# only build supersonic surrogates if necessary
if len(sup_Mach) > 2:
surrogates.supersonic = build_surrogate(aerodynamics, training.supersonic, vehicle)
surrogates.transonic = build_surrogate(aerodynamics, training.transonic, vehicle)
else:
surrogates.supersonic = no_surrogate(aerodynamics, training.supersonic, vehicle)
surrogates.transonic = no_surrogate(aerodynamics, training.transonic, vehicle)
return
[docs]
def build_surrogate(aerodynamics, training, vehicle):
# unpack data
surrogates = Data()
mach_data = training.Mach
AoA_data = aerodynamics.training.angle_of_attack
Beta_data = aerodynamics.training.sideslip_angle
# Pack the outputs
surrogates.Clift_alpha = RegularGridInterpolator((AoA_data ,mach_data),training.Clift_alpha ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.Cdrag_induced_alpha= RegularGridInterpolator((AoA_data ,mach_data),training.Cdrag_induced_alpha,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CM_alpha = RegularGridInterpolator((AoA_data ,mach_data),training.CM_alpha ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CX_alpha = RegularGridInterpolator((AoA_data ,mach_data),training.CX_alpha ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CZ_alpha = RegularGridInterpolator((AoA_data ,mach_data),training.CZ_alpha ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CY_alpha = RegularGridInterpolator((AoA_data ,mach_data),training.CY_alpha ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CL_alpha = RegularGridInterpolator((AoA_data ,mach_data),training.CL_alpha ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CN_alpha = RegularGridInterpolator((AoA_data ,mach_data),training.CN_alpha ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.Clift_spanwise = RegularGridInterpolator((AoA_data, mach_data),training.Clift_spanwise ,method='linear', bounds_error=False, fill_value=None)
surrogates.Clift_beta = RegularGridInterpolator((Beta_data ,mach_data),training.Clift_beta ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.Cdrag_induced_beta = RegularGridInterpolator((Beta_data ,mach_data),training.Cdrag_induced_beta,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CX_beta = RegularGridInterpolator((Beta_data ,mach_data),training.CX_beta ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CZ_beta = RegularGridInterpolator((Beta_data ,mach_data),training.CZ_beta ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CY_beta = RegularGridInterpolator((Beta_data ,mach_data),training.CY_beta ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CL_beta = RegularGridInterpolator((Beta_data ,mach_data),training.CL_beta ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CN_beta = RegularGridInterpolator((Beta_data ,mach_data),training.CN_beta ,method = 'linear', bounds_error=False, fill_value=None)
surrogates.CM_beta = RegularGridInterpolator((Beta_data ,mach_data),training.CM_beta ,method = 'linear', bounds_error=False, fill_value=None)
# Use interpolat.interp1d below
surrogates.CM_0 = interpolate.interp1d(mach_data, training.CM_0, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dClift_dalpha = interpolate.interp1d(mach_data, training.dClift_dalpha, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCX_dalpha = interpolate.interp1d(mach_data, training.dCX_dalpha, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCX_du = interpolate.interp1d(mach_data, training.dCX_du, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCY_dbeta = interpolate.interp1d(mach_data,training.dCY_dbeta, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCY_dr = interpolate.interp1d(mach_data,training.dCY_dr, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCZ_dalpha = interpolate.interp1d(mach_data,training.dCZ_dalpha, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCZ_du = interpolate.interp1d(mach_data,training.dCZ_du, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCZ_dq = interpolate.interp1d(mach_data,training.dCZ_dq, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCL_dbeta = interpolate.interp1d(mach_data,training.dCL_dbeta, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCL_dp = interpolate.interp1d(mach_data,training.dCL_dp, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCL_dr = interpolate.interp1d(mach_data,training.dCL_dr, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCM_dalpha = interpolate.interp1d(mach_data,training.dCM_dalpha, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCM_du = interpolate.interp1d(mach_data,training.dCM_du, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCM_dq = interpolate.interp1d(mach_data,training.dCM_dq, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCN_dbeta = interpolate.interp1d(mach_data,training.dCN_dbeta, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCN_dp = interpolate.interp1d(mach_data,training.dCN_dp, kind='linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCN_dr = interpolate.interp1d(mach_data,training.dCN_dr, kind='linear', bounds_error=False, fill_value='extrapolate')
if aerodynamics.aileron_flag:
surrogates.dCY_ddelta_a = interpolate.interp1d(mach_data,training.dCY_ddelta_a , kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCL_ddelta_a = interpolate.interp1d(mach_data,training.dCL_ddelta_a , kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCN_ddelta_a = interpolate.interp1d(mach_data,training.dCN_ddelta_a , kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCdrag_ddelta_a = interpolate.interp1d(mach_data,training.dCdrag_ddelta_a , kind = 'linear', bounds_error=False, fill_value='extrapolate')
if aerodynamics.elevator_flag:
surrogates.dCM_ddelta_e = interpolate.interp1d(mach_data,training.dCM_ddelta_e ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dClift_ddelta_e = interpolate.interp1d(mach_data,training.dClift_ddelta_e ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCdrag_ddelta_e = interpolate.interp1d(mach_data,training.dCdrag_ddelta_e ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
if aerodynamics.rudder_flag:
surrogates.dCY_ddelta_r = interpolate.interp1d(mach_data,training.dCY_ddelta_r ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCN_ddelta_r = interpolate.interp1d(mach_data,training.dCN_ddelta_r ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCL_ddelta_r = interpolate.interp1d(mach_data,training.dCL_ddelta_r ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCdrag_ddelta_r = interpolate.interp1d(mach_data,training.dCdrag_ddelta_r ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
if aerodynamics.flap_flag:
surrogates.dCM_ddelta_f = interpolate.interp1d(mach_data,training.dCM_ddelta_f ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dClift_ddelta_f = interpolate.interp1d(mach_data,training.dClift_ddelta_f ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCdrag_ddelta_f = interpolate.interp1d(mach_data,training.dCdrag_ddelta_f ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
if aerodynamics.slat_flag:
surrogates.dCM_ddelta_s = interpolate.interp1d(mach_data,training.dCM_ddelta_s ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dClift_ddelta_s = interpolate.interp1d(mach_data,training.dClift_ddelta_s ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
surrogates.dCdrag_ddelta_s = interpolate.interp1d(mach_data,training.dCdrag_ddelta_s ,kind = 'linear', bounds_error=False, fill_value='extrapolate')
return surrogates
[docs]
def no_surrogate(aerodynamics, training, vehicle):
# unpack data
surrogates = Data()
# Pack the outputs
surrogates.Clift_alpha = None
surrogates.Clift_beta = None
surrogates.Clift_spanwise = None
surrogates.Cdrag_induced_alpha = None
surrogates.Cdrag_induced_beta = None
surrogates.CX_alpha = None
surrogates.CX_beta = None
surrogates.CY_alpha = None
surrogates.CY_beta = None
surrogates.CZ_alpha = None
surrogates.CZ_beta = None
surrogates.CL_alpha = None
surrogates.CL_beta = None
surrogates.CM_alpha = None
surrogates.CM_beta = None
surrogates.CN_alpha = None
surrogates.CN_beta = None
surrogates.CM_0 = None
surrogates.dClift_dalpha = None
surrogates.dCX_dalpha = None
surrogates.dCX_du = None
surrogates.dCY_dbeta = None
surrogates.dCY_dr = None
surrogates.dCZ_dalpha = None
surrogates.dCZ_du = None
surrogates.dCZ_dq = None
surrogates.dCL_dbeta = None
surrogates.dCL_dp = None
surrogates.dCL_dr = None
surrogates.dCM_dalpha = None
surrogates.dCM_du = None
surrogates.dCM_dq = None
surrogates.dCN_dbeta = None
surrogates.dCN_dp = None
surrogates.dCN_dr = None
if aerodynamics.aileron_flag:
surrogates.dCY_ddelta_a = None
surrogates.dCL_ddelta_a = None
surrogates.dCN_ddelta_a = None
surrogates.dCdrag_ddelta_a = None
if aerodynamics.elevator_flag:
surrogates.dClift_ddelta_e = None
surrogates.dCM_ddelta_e = None
surrogates.dClift_ddelta_e = None
surrogates.dCdrag_ddelta_e = None
if aerodynamics.rudder_flag:
surrogates.dCY_ddelta_r = None
surrogates.dCL_ddelta_r = None
surrogates.dCN_ddelta_r = None
surrogates.dCdrag_ddelta_r = None
if aerodynamics.flap_flag:
surrogates.dClift_ddelta_f = None
surrogates.dCM_ddelta_f = None
surrogates.dCdrag_ddelta_f = None
if aerodynamics.slat_flag:
surrogates.dClift_ddelta_s = None
surrogates.dCM_ddelta_s = None
surrogates.dCdrag_ddelta_s = None
return surrogates
