Source code for RCAIDE.Library.Mission.Common.Update.forces
# RCAIDE/Library/Missions/Common/Update/forces.py
#
#
# Created: Jul 2023, M. Clarke
# ----------------------------------------------------------------------------------------------------------------------
# IMPORT
# ----------------------------------------------------------------------------------------------------------------------
# RCAIDE imports
import RCAIDE
from RCAIDE.Framework.Core import orientation_product, orientation_transpose
import numpy as np
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# Update Forces
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[docs]
def forces(segment):
""" Updates the total resultant force on the vehicle
Assumptions:
N/A
Inputs:
segment.state.conditions.:
frames.wind.force_vector [N]
frames.body.thrust_force_vector [N]
frames.inertial.gravity_force_vector [N]
Outputs:
segment.conditions
frames.inertial.total_force_vector [N]
Properties Used:
N/A
"""
# unpack
conditions = segment.state.conditions
F_aero_w = conditions.frames.wind.force_vector
F_thrust_body = conditions.frames.body.thrust_force_vector
F_weight_i = conditions.frames.inertial.gravity_force_vector
# unpack transformation matrices
T_body2inertial = conditions.frames.body.transform_to_inertial
T_wind2inertial = conditions.frames.wind.transform_to_inertial
T_wind2body = conditions.frames.wind.transform_to_body
T_inertial2body = orientation_transpose(T_body2inertial)
T_body2wind = orientation_transpose(T_wind2body)
# transform matrices
F_aero_i = orientation_product(T_wind2inertial,F_aero_w)
F_thrust_i = orientation_product(T_body2inertial,F_thrust_body)
F_thrust_wind = orientation_product(T_body2wind,F_thrust_body)
F_weight_body = orientation_product(T_inertial2body, F_weight_i)
F_weight_wind = orientation_product(T_body2wind,F_weight_body)
if type(segment) == RCAIDE.Framework.Mission.Segments.Vertical_Flight.Climb or \
type(segment) == RCAIDE.Framework.Mission.Segments.Vertical_Flight.Descent:
F_aero_i = np.zeros_like(F_thrust_i)
F_aero_w = np.zeros_like(F_thrust_i)
F_weight_wind[:, [0, 2]] = F_weight_wind[:, [2, 0]]
F_thrust_wind[:, [0, 2]] = F_thrust_wind[:, [2, 0]]
F_weight_i[:,1] *= -1
F_weight_wind[:,1] *= -1
# sum of the forces
F_tot_i = F_aero_i + F_thrust_i + F_weight_i
F_tot_w = F_aero_w + F_thrust_wind + F_weight_wind
# pack
conditions.frames.inertial.total_force_vector[:,:] = F_tot_i[:,:]
conditions.frames.wind.total_force_vector[:,:] = F_tot_w[:,:]
return
