Merge pull request #51 from AlexS12/trimmer

Steady-state trimmer

Según lo hablado en la [reunión 3](https://github.com/AeroPython/PyFME/wiki/Reuni%C3%B3n-3) se hace el merge.

* Las validaciones se han hecho sobre el modelo de avión actual.
* Los casos de ejemplo se mejorarán con el trabajo en los issues #58 y #57 (@olrosales) 
* La inicialización se mejorará buscando algún método empírico simplificado (@JuanMatSa)

.travis.yml

@@ -22,7 +22,7 @@ before_install:
  - source activate test-environment
 
 install:
- - conda install numpy pytest
+ - conda install numpy pytest scipy
  - pip install -e .
 
 script:

environment.yml

@@ -1,3 +1,4 @@
 name: pyfme
 dependencies:
  - numpy >=1.7
+ - scipy >=0.17.0

examples/example_001.py

@@ -1,82 +1,151 @@
 # -*- coding: utf-8 -*-
 """
-Dummy example
-
-@author: asaez
+Python Flight Mechanics Engine (PyFME).
+Copyright (c) AeroPython Development Team.
+Distributed under the terms of the MIT License.
+
+Example with trimmed aircraft.
+The main purpose of this example is to check if the aircraft trimmed in a given
+state maintains the trimmed flight condition.
+Trimmed in stationary, horizontal, symmetric, wings level flight.
 """
 
 import numpy as np
 import matplotlib.pyplot as plt
 
+from pyfme.aircrafts import cessna_310
 from pyfme.models.system import System
+from pyfme.utils.trimmer import steady_state_flight_trim
+from pyfme.utils.anemometry import calculate_alpha_beta_TAS
+from pyfme.environment.isa import atm
 
 
+if __name__ == '__main__':
 
-def forces():
- return np.array([0, 0, -9.8*500])
-
-
-def moments():
- return np.array([0, 0, 0])
-
+ # Aircraft parameters.
+ mass, inertia = cessna_310.mass_and_inertial_data()
 
-if __name__ == '__main__':
+ # Initial conditions.
+ TAS_ = 312 * 0.3048 # m/s
+ h = 8000 * 0.3048 # m
+ psi_0 = 3 # rad
+ x_0, y_0 = 0, 0 # m
 
- # Case params
- mass = 500
- inertia = np.array([[1, 0, 0],
- [0, 1, 0],
- [0, 0, 1]])
+ # Trimming.
+ trim_results = steady_state_flight_trim(cessna_310, h, TAS_, gamma=0,
+ turn_rate=0)
 
- # initial conditions
- u, v, w = 0, 0, 0
- p, q, r = 0, 0, 0
+ lin_vel, ang_vel, theta, phi, alpha_, beta_, control_vector = trim_results
 
- theta, phi, psi = 0, 0, 0
- x, y, z = 0, 0, 5000
+ # Time.
+ t0 = 0 # s
+ tf = 30 # s
+ dt = 1e-2 # s
 
- t0 = 0
- tf = 10
- dt = 1e-2
  time = np.arange(t0, tf, dt)
 
+ # Results initialization.
  results = np.zeros([time.size, 12])
 
- velocities = np.empty([time.size, 6])
- results[0, 0:6] = u, v, w, p, q, r
- results[0, 6:9] = theta, phi, psi
- results[0, 9:12] = x, y, z
+ results[0, 0:3] = lin_vel
+ results[0, 3:6] = ang_vel
+ results[0, 6:9] = theta, phi, psi_0
+ results[0, 9:12] = x_0, y_0, h
+ alpha = np.empty_like(time)
+ alpha[0] = alpha_
+ beta = np.empty_like(time)
+ beta[0] = beta_
+ TAS = np.empty_like(time)
+ TAS[0] = TAS_
+
+ # Linear Momentum and Angular Momentum eqs.
+ equations = System(integrator='dopri5',
+ model='euler_flat_earth',
+ jac=False)
+ u, v, w = lin_vel
+ p, q, r = ang_vel
+
+ equations.set_initial_values(u, v, w,
+ p, q, r,
+ theta, phi, psi_0,
+ x_0, y_0, h)
+
+ _, _, rho, _ = atm(h)
+
+ # Define control vectors.
+ d_e, d_a, d_r, d_t = control_vector
+
+ attitude = theta, phi, psi_0
+
+ # Rename function to make it shorter
+ forces_and_moments = cessna_310.get_forces_and_moments
+ for ii, t in enumerate(time[1:]):
 
- # Linear Momentum and Angular Momentum eqs
- equations = System(integrator='dopri5', model='euler_flat_earth', jac=False)
- equations.set_initial_values(u, v, w, p, q, r, theta, phi, psi, x, y, z)
+ forces, moments = forces_and_moments(TAS[ii], rho, alpha[ii], beta[ii],
+ d_e, 0, d_a, d_r, d_t, attitude)
 
+ results[ii+1, :] = equations.propagate(mass, inertia, forces, moments,
+ dt)
 
- for ii, t in enumerate(time[1:]):
- results[ii+1, :] = equations.propagate(mass, inertia, forces(), moments(),
- dt=dt)
+ lin_vel = results[ii+1, 0:3]
+ ang_vel = results[ii+1, 3:6]
+ attitude = results[ii+1, 6:9]
+ position = results[ii+1, 9:12]
+
+ alpha[ii+1], beta[ii+1], TAS[ii+1] = calculate_alpha_beta_TAS(*lin_vel)
+
+ _, _, rho, _ = atm(position[2])
 
  velocities = results[:, 0:6]
  attitude_angles = results[:, 6:9]
  position = results[:, 9:12]
 
- # TODO: improve graphics: legend title....
+ # PLOTS
+ plt.close('all')
+ plt.style.use('ggplot')
+
  plt.figure('pos')
- plt.plot(time, position[:, 0])
- plt.plot(time, position[:, 1])
- plt.plot(time, position[:, 2])
+ plt.plot(time, position[:, 0], label='x')
+ plt.plot(time, position[:, 1], label='y')
+ plt.plot(time, position[:, 2], label='z')
+ plt.xlabel('time (s)')
+ plt.ylabel('position (m)')
+ plt.legend()
 
  plt.figure('angles')
- plt.plot(time, attitude_angles[:, 0])
- plt.plot(time, attitude_angles[:, 1])
- plt.plot(time, attitude_angles[:, 2])
+ plt.plot(time, attitude_angles[:, 0], label='theta')
+ plt.plot(time, attitude_angles[:, 1], label='phi')
+ plt.plot(time, attitude_angles[:, 2], label='psi')
+ plt.xlabel('time (s)')
+ plt.ylabel('attitude (rad)')
+ plt.legend()
 
  plt.figure('velocities')
- plt.plot(time, velocities[:, 0])
- plt.plot(time, velocities[:, 1])
- plt.plot(time, velocities[:, 2])
+ plt.plot(time, velocities[:, 0], label='u')
+ plt.plot(time, velocities[:, 1], label='v')
+ plt.plot(time, velocities[:, 2], label='w')
+ plt.plot(time, TAS, label='TAS')
+ plt.xlabel('time (s)')
+ plt.ylabel('velocity (m/s)')
+ plt.legend()
 
  plt.figure('ang velocities')
- plt.plot(time, velocities[:, 3])
- plt.plot(time, velocities[:, 4])
- plt.plot(time, velocities[:, 5])
+ plt.plot(time, velocities[:, 3], label='p')
+ plt.plot(time, velocities[:, 4], label='q')
+ plt.plot(time, velocities[:, 5], label='r')
+ plt.xlabel('time (s)')
+ plt.ylabel('angular velocity (rad/s)')
+ plt.legend()
+
+ plt.figure('aero angles')
+ plt.plot(time, alpha, label='alpha')
+ plt.plot(time, beta, label='beta')
+ plt.xlabel('time (s)')
+ plt.ylabel('angle (rad)')
+ plt.legend()
+
+ plt.figure('2D Trajectory')
+ plt.plot(position[:, 0], position[:, 1])
+ plt.xlabel('X (m)')
+ plt.ylabel('Y (m)')
+ plt.legend()

examples/example_002.py

@@ -0,0 +1,151 @@
+# -*- coding: utf-8 -*-
+"""
+Python Flight Mechanics Engine (PyFME).
+Copyright (c) AeroPython Development Team.
+Distributed under the terms of the MIT License.
+
+Example with trimmed aircraft.
+The main purpose of this example is to check if the aircraft trimmed in a given
+state maintains the trimmed flight condition.
+Trimmed in stationary descent, symmetric, wings level flight.
+"""
+
+import numpy as np
+import matplotlib.pyplot as plt
+
+from pyfme.aircrafts import cessna_310
+from pyfme.models.system import System
+from pyfme.utils.trimmer import steady_state_flight_trim
+from pyfme.utils.anemometry import calculate_alpha_beta_TAS
+from pyfme.environment.isa import atm
+
+
+if __name__ == '__main__':
+
+ # Aircraft parameters.
+ mass, inertia = cessna_310.mass_and_inertial_data()
+
+ # Initial conditions.
+ TAS_ = 312 * 0.3048 # m/s
+ h = 8000 * 0.3048 # m
+ psi_0 = 3 # rad
+ x_0, y_0 = 0, 0 # m
+
+ # Trimming.
+ trim_results = steady_state_flight_trim(cessna_310, h, TAS_, gamma=0.20,
+ turn_rate=0)
+
+ lin_vel, ang_vel, theta, phi, alpha_, beta_, control_vector = trim_results
+
+ # Time.
+ t0 = 0 # s
+ tf = 120 # s
+ dt = 1e-2 # s
+
+ time = np.arange(t0, tf, dt)
+
+ # Results initialization.
+ results = np.zeros([time.size, 12])
+
+ results[0, 0:3] = lin_vel
+ results[0, 3:6] = ang_vel
+ results[0, 6:9] = theta, phi, psi_0
+ results[0, 9:12] = x_0, y_0, h
+ alpha = np.empty_like(time)
+ alpha[0] = alpha_
+ beta = np.empty_like(time)
+ beta[0] = beta_
+ TAS = np.empty_like(time)
+ TAS[0] = TAS_
+
+ # Linear Momentum and Angular Momentum eqs.
+ equations = System(integrator='dopri5',
+ model='euler_flat_earth',
+ jac=False)
+ u, v, w = lin_vel
+ p, q, r = ang_vel
+
+ equations.set_initial_values(u, v, w,
+ p, q, r,
+ theta, phi, psi_0,
+ x_0, y_0, h)
+
+ _, _, rho, _ = atm(h)
+
+ # Define control vectors.
+ d_e, d_a, d_r, d_t = control_vector
+
+ attitude = theta, phi, psi_0
+
+ # Rename function to make it shorter
+ forces_and_moments = cessna_310.get_forces_and_moments
+ for ii, t in enumerate(time[1:]):
+
+ forces, moments = forces_and_moments(TAS[ii], rho, alpha[ii], beta[ii],
+ d_e, 0, d_a, d_r, d_t, attitude)
+
+ results[ii+1, :] = equations.propagate(mass, inertia, forces, moments,
+ dt)
+
+ lin_vel = results[ii+1, 0:3]
+ ang_vel = results[ii+1, 3:6]
+ attitude = results[ii+1, 6:9]
+ position = results[ii+1, 9:12]
+
+ alpha[ii+1], beta[ii+1], TAS[ii+1] = calculate_alpha_beta_TAS(*lin_vel)
+
+ _, _, rho, _ = atm(position[2])
+
+ velocities = results[:, 0:6]
+ attitude_angles = results[:, 6:9]
+ position = results[:, 9:12]
+
+ # PLOTS
+ plt.close('all')
+ plt.style.use('ggplot')
+
+ plt.figure('pos')
+ plt.plot(time, position[:, 0], label='x')
+ plt.plot(time, position[:, 1], label='y')
+ plt.plot(time, position[:, 2], label='z')
+ plt.xlabel('time (s)')
+ plt.ylabel('position (m)')
+ plt.legend()
+
+ plt.figure('angles')
+ plt.plot(time, attitude_angles[:, 0], label='theta')
+ plt.plot(time, attitude_angles[:, 1], label='phi')
+ plt.plot(time, attitude_angles[:, 2], label='psi')
+ plt.xlabel('time (s)')
+ plt.ylabel('attitude (rad)')
+ plt.legend()
+
+ plt.figure('velocities')
+ plt.plot(time, velocities[:, 0], label='u')
+ plt.plot(time, velocities[:, 1], label='v')
+ plt.plot(time, velocities[:, 2], label='w')
+ plt.plot(time, TAS, label='TAS')
+ plt.xlabel('time (s)')
+ plt.ylabel('velocity (m/s)')
+ plt.legend()
+
+ plt.figure('ang velocities')
+ plt.plot(time, velocities[:, 3], label='p')
+ plt.plot(time, velocities[:, 4], label='q')
+ plt.plot(time, velocities[:, 5], label='r')
+ plt.xlabel('time (s)')
+ plt.ylabel('angular velocity (rad/s)')
+ plt.legend()
+
+ plt.figure('aero angles')
+ plt.plot(time, alpha, label='alpha')
+ plt.plot(time, beta, label='beta')
+ plt.xlabel('time (s)')
+ plt.ylabel('angle (rad)')
+ plt.legend()
+
+ plt.figure('2D Trajectory')
+ plt.plot(position[:, 0], position[:, 1])
+ plt.xlabel('X (m)')
+ plt.ylabel('Y (m)')
+ plt.legend()