guess_maker = beluga.guess_generator('auto',
                                     start=[50000, 0, 4000, -89 * pi / 180],
                                     control_guess=[0],
                                     direction='forward',
                                     costate_guess=-0.1)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
                .num_cases(101) \
                .const('h_f', 0) \
                .const('theta_f', 0.01*pi/180)

continuation_steps.add_step('bisection') \
                .num_cases(11) \
                .const('theta_f', 5.0*pi/180) \

beluga.add_logger(file_level=logging.DEBUG, display_level=logging.INFO)

sol_set = beluga.solve(ocp=ocp,
                       method='indirect',
                       optim_options={
                           'analytical_jacobian': False,
                           'control_method': 'algebraic'
                       },
                       bvp_algorithm=bvp_solver,
                       steps=continuation_steps,
                       guess_generator=guess_maker,
                       autoscale=False)
Пример #2
0
ocp.terminal_constraint('y-y_f', 'ft')

ocp.scale(ft='y', s='y/v', rad=1)

bvp_solver = beluga.bvp_algorithm('Shooting')

guess_maker = beluga.guess_generator('auto',
                                     start=[0, 0, 0],
                                     costate_guess=-0.1,
                                     control_guess=[-3.14159 / 2],
                                     use_control_guess=True,
                                     time_integrate=0.1)

beluga.add_logger(display_level=logging.INFO)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
    .num_cases(21) \
    .const('x_f', 10) \
    .const('y_f', -10)

sol_set = beluga.solve(ocp=ocp,
                       method='indirect',
                       bvp_algorithm=bvp_solver,
                       steps=continuation_steps,
                       guess_generator=guess_maker,
                       autoscale=True,
                       initial_helper=True,
                       save_sols='brachisto.beluga')
Пример #3
0
                .terminal('xbar2', -0.6)\
                .terminal('ybar2', .25) \
                .terminal('zbar2', 0.) \
                .terminal('psi2', -15*pi/180) \

continuation_steps.add_step('bisection') \
                .num_cases(21) \
                .terminal('xbar',0.0)\
                .terminal('xbar2',0.0)\
                .terminal('ybar',0.0)\
                .terminal('ybar2',0.0)\
#

# continuation_steps.add_step('bisection') \
#                 .num_cases(11) \
#                 .terminal('psi',15*pi/180)\
#                 .terminal('psi2',-15*pi/180)

# guess_maker = beluga.guess_generator('file',filename='data-zs-unc-qcpi.dill',iteration=-1,step=-1)
#
# continuation_steps.add_step('bisection') \
#                 .num_cases(101) \
#                 .constant('zc',-0.125)

beluga.solve(ocp,
             method='icrm',
             bvp_algorithm=bvp_solver,
             steps=continuation_steps,
             guess_generator=guess_maker,
             output_file='data.dill')
Пример #4
0
def test_planarhypersonic():
    from math import pi
    import beluga

    ocp = beluga.OCP('planarHypersonic')

    # Define independent variables
    ocp.independent('t', 's')

    # Define equations of motion
    ocp.state('h', 'v*sin(gam)', 'm') \
        .state('theta', 'v*cos(gam)/r', 'rad') \
        .state('v', '-D/mass - mu*sin(gam)/r**2', 'm/s') \
        .state('gam', 'L/(mass*v) + (v/r - mu/(v*r^2))*cos(gam)', 'rad')

    # Define quantities used in the problem
    ocp.quantity('rho', 'rho0*exp(-h/H)')
    ocp.quantity('Cl', '(1.5658*alfa + -0.0000)')
    ocp.quantity('Cd', '(1.6537*alfa^2 + 0.0612)')
    ocp.quantity('D', '0.5*rho*v^2*Cd*Aref')
    ocp.quantity('L', '0.5*rho*v^2*Cl*Aref')
    ocp.quantity('r', 're+h')

    # Define controls
    ocp.control('alfa', 'rad')

    # Define constants
    ocp.constant('mu', 3.986e5 * 1e9,
                 'm^3/s^2')  # Gravitational parameter, m^3/s^2
    ocp.constant('rho0', 0.0001 * 1.2,
                 'kg/m^3')  # Sea-level atmospheric density, kg/m^3
    ocp.constant('H', 7500, 'm')  # Scale height for atmosphere of Earth, m

    ocp.constant('mass', 750 / 2.2046226, 'kg')  # Mass of vehicle, kg
    ocp.constant('re', 6378000, 'm')  # Radius of planet, m
    ocp.constant('Aref',
                 pi * (24 * .0254 / 2)**2,
                 'm^2')  # Reference area of vehicle, m^2
    ocp.constant('h_0', 80000, 'm')
    ocp.constant('v_0', 4000, 'm/s')
    ocp.constant('h_f', 80000, 'm')
    ocp.constant('theta_f', 0, 'rad')

    # Define costs
    ocp.terminal_cost('-v^2', 'm^2/s^2')

    # Define constraints
    ocp.constraints() \
        .initial('h-h_0', 'm') \
        .initial('theta', 'rad') \
        .initial('v-v_0', 'm/s') \
        .terminal('h-h_f', 'm') \
        .terminal('theta-theta_f', 'rad')

    ocp.scale(m='h', s='h/v', kg='mass', rad=1)

    bvp_solver = beluga.bvp_algorithm('Shooting',
                                      algorithm='SLSQP',
                                      tolerance=1e-6)

    guess_maker = beluga.guess_generator(
        'auto',
        start=[80000, 0, 4000, -90 * pi / 180],
        direction='forward',
        costate_guess=-0.1)

    continuation_steps = beluga.init_continuation()

    continuation_steps.add_step('bisection') \
        .num_cases(11) \
        .const('h_f', 0) \
        .const('theta_f', 0.01 * pi / 180)

    continuation_steps.add_step('bisection') \
        .num_cases(11) \
        .const('theta_f', 5.0 * pi / 180)

    continuation_steps.add_step('bisection') \
                .num_cases(11) \
                .const('rho0', 1.2)

    sol = beluga.solve(ocp,
                       method='traditional',
                       bvp_algorithm=bvp_solver,
                       steps=continuation_steps,
                       guess_generator=guess_maker)

    y0 = sol.y[0]
    yf = sol.y[-1]

    y0e = [
        8.00000000e+04, 0.00000000e+00, 4.00000000e+03, 1.95069984e-02,
        -1.68249327e+01, 1.21634197e+06, -2.83598229e+03, -6.15819100e-17
    ]
    yfe = [
        5.23214346e-04, 8.72664626e-02, 2.69147623e+03, -9.38246813e-01,
        5.46455659e+02, 1.21634197e+06, -5.38295257e+03, 1.67911185e-01
    ]
    tfe = 144.5678

    assert sol.t.shape[0] == sol.y.shape[0]
    assert sol.t.shape[0] == sol.u.shape[0]
    assert sol.y.shape[1] == 8
    assert sol.u.shape[1] == 1
    assert abs((y0[0] - y0e[0]) / y0e[0]) < tol
    assert abs((y0[1] - y0e[1])) < tol
    assert abs((y0[2] - y0e[2]) / y0e[2]) < tol
    assert abs((y0[3] - y0e[3]) / y0e[3]) < tol
    assert abs((y0[4] - y0e[4]) / y0e[4]) < tol
    assert abs((y0[5] - y0e[5]) / y0e[5]) < tol
    assert abs((y0[6] - y0e[6]) / y0e[6]) < tol
    assert abs((y0[7] - y0e[7])) < tol
    assert abs((sol.t[-1] - tfe) / tfe) < tol
    assert abs((yf[0] - yfe[0])) < tol
    assert abs((yf[1] - yfe[1]) / yfe[1]) < tol
    assert abs((yf[2] - yfe[2]) / yfe[2]) < tol
    assert abs((yf[3] - yfe[3]) / yfe[3]) < tol
    assert abs((yf[4] - yfe[4]) / yfe[4]) < tol
    assert abs((yf[5] - yfe[5]) / yfe[5]) < tol
    assert abs((yf[6] - yfe[6]) / yfe[6]) < tol
    assert abs((yf[7] - yfe[7]) / yfe[7]) < tol
Пример #5
0
continuation_steps.add_step('bisection') \
                .num_cases(20) \
                .const('y_0', 1000)

continuation_steps.add_step('bisection') \
                .num_cases(10) \
                .const('um', 2.5)

continuation_steps.add_step('bisection') \
                .num_cases(25, 'log') \
                .const('eps', 5e-2)

# continuation_steps.add_step('bisection') \
#                 .num_cases(15, 'log') \
#                 .k('eps', 1e1)

beluga.add_logger(file_level=logging.INFO, display_level=logging.INFO)

sol_set = beluga.solve(ocp=ocp,
                       method='traditional',
                       optim_options={
                           'control_method': 'differential',
                           'analytical_jacobian': False
                       },
                       bvp_algorithm=bvp_solver,
                       steps=continuation_steps,
                       guess_generator=guess_maker,
                       autoscale=False,
                       initial_helper=True)
continuation_steps.add_step('bisection') \
                .num_cases(11) \
                .const('gam_0', -80*pi/180) \
                .const('theta_f', 0.5*pi/180)

continuation_steps.add_step('bisection') \
                .num_cases(31) \
                .const('gam_0', -0*pi/180) \
                .const('theta_f', 3*pi/180)

beluga.add_logger(file_level=logging.DEBUG, display_level=logging.INFO)

cont_planar = beluga.solve(ocp=ocp,
                           method='indirect',
                           optim_options={'control_method': 'differential'},
                           bvp_algorithm=bvp_solver,
                           steps=continuation_steps,
                           guess_generator=guess_maker,
                           initial_helper=True)

sol = cont_planar[-1][-1]

'''
Begin the 3 dof portion of the solution process.
'''
ocp_2 = beluga.Problem('hypersonic3DOF')

# Define independent variables
ocp_2.independent('t', 's')

rho = 'rho0*exp(-h/H)'
Пример #7
0
ocp.scale(m='y', s='y/v_x', kg='mass', newton='mass*v_x^2/y', rad=1)

bvp_solver = beluga.bvp_algorithm('spbvp')

guess_maker = beluga.guess_generator(
    'auto',
    start=[0, 0, 0, 0.01, 60880],  # Starting values for states in order
    costate_guess=-0.1,
    control_guess=[0],
    use_control_guess=False)

beluga.add_logger(logging_level=logging.DEBUG, display_level=logging.INFO)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
                .num_cases(10) \
                .const('eps', 1) \
                .const('mass_0', 1.1702e5)

continuation_steps.add_step('bisection') \
                .num_cases(10) \
                .const('rho_ref', 1.225)

sol_set = beluga.solve(ocp=ocp,
                       method='indirect',
                       bvp_algorithm=bvp_solver,
                       steps=continuation_steps,
                       guess_generator=guess_maker,
                       autoscale=True)
Пример #8
0
                                     start=[0, 0],
                                     costate_guess=-0.1,
                                     time_integrate=1.1,
                                     control_guess=[0],
                                     use_control_guess=True)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
                .num_cases(6) \
                .const('x_f', 1) \
                .const('y_f', 0) \
                .const('s_f', 1.1)

continuation_steps.add_step('bisection') \
                .num_cases(6) \
                .const('x_f', 1) \
                .const('y_f', 0) \
                .const('s_f', 3)

beluga.add_logger(display_level=logging.INFO)

sol_set = beluga.solve(ocp=ocp,
                       method='traditional',
                       bvp_algorithm=bvp_solver,
                       steps=continuation_steps,
                       guess_generator=guess_maker,
                       autoscale=True,
                       initial_helper=True,
                       save_sols='chain.beluga')
Пример #9
0
    .const('gam_0', -1*np.pi/180)

continuation_steps.add_step('bisection') \
    .num_cases(80) \
    .const('h_0', h_0) \
    .const('v_0', v_0 - 1000)

continuation_steps.add_step('bisection') \
    .num_cases(20) \
    .const('psi_0', 90*pi/180)

continuation_steps.add_step('bisection') \
    .num_cases(30) \
    .const('fpa', 1) \
    .const('v_0', v_0) \
    .const('eps', 1e-5)

beluga.add_logger(file_level=logging.DEBUG, display_level=logging.INFO)

sol_set = beluga.solve(ocp=ocp,
                       method='indirect',
                       bvp_algorithm=bvp_solver,
                       steps=continuation_steps,
                       guess_generator=guess_maker,
                       optim_options={
                           'control_method': 'differential',
                           'analytical_jacobian': False
                       },
                       initial_helper=True,
                       save_sols='space_shuttle.beluga')
Пример #10
0
bvp_solver_indirect = beluga.bvp_algorithm('spbvp')

guess_maker_indirect = beluga.guess_generator('auto',
                                              start=[0, 0, 0],
                                              direction='forward',
                                              costate_guess=-0.1,
                                              control_guess=[0.0],
                                              use_control_guess=True,
                                              time_integrate=3.1415 / 2)

beluga.add_logger(file_level=logging.DEBUG, display_level=logging.INFO)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
                .num_cases(60, 'log') \
                .const('epsilon1', 1e-9)

sol_set = beluga.solve(ocp=ocp,
                       method='indirect',
                       optim_options={
                           'analytical_jacobian': True,
                           'control_method': 'differential'
                       },
                       bvp_algorithm=bvp_solver_indirect,
                       steps=continuation_steps,
                       guess_generator=guess_maker_indirect,
                       autoscale=False,
                       initial_helper=False)
Пример #11
0
                                              direction='forward',
                                              costate_guess=-0.1,
                                              control_guess=[0],
                                              use_control_guess=True,
                                              time_integrate=0.1)

beluga.add_logger(logging_level=logging.DEBUG, display_level=logging.INFO)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
    .num_cases(5) \
    .const('i_0', i_0)

continuation_steps.add_step('bisection') \
    .num_cases(20, 'log') \
    .const('lu', lu) \
    .const('lq', lq)

continuation_steps.add_step('bisection') \
    .num_cases(20, 'log') \
    .const('eps1', 1e-2)

sol_set_indirect = beluga.solve(ocp=ocp,
                                method='indirect',
                                optim_options={'control_method': 'icrm'},
                                bvp_algorithm=bvp_solver_indirect,
                                steps=continuation_steps,
                                guess_generator=guess_maker_indirect,
                                autoscale=False)
Пример #12
0
    control_guess=[0],
    use_control_guess=True)

beluga.add_logger(logging_level=logging.DEBUG, display_level=logging.INFO)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
    .num_cases(10) \
    .const('h_f', 0) \
    .const('v_f', 0)

continuation_steps.add_step('bisection') \
    .num_cases(10) \
    .const('u_lower', 0) \
    .const('u_upper', 4)

continuation_steps.add_step('bisection') \
    .num_cases(30, 'log') \
    .const('epsilon1', 1e-5)

sol_set = beluga.solve(ocp=ocp,
                       method='indirect',
                       optim_options={
                           'analytical_jacobian': True,
                           'control_method': 'icrm'
                       },
                       bvp_algorithm=bvp_solver,
                       steps=continuation_steps,
                       guess_generator=guess_maker)
Пример #13
0
continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
    .num_cases(21) \
    .const('h_f', 0) \
    .const('theta_f', 50e3/re)

continuation_steps.add_step('bisection') \
    .num_cases(81) \
    .const('theta_f', 300e3/re)

continuation_steps.add_step('bisection') \
    .num_cases(41) \
    .const('gam_0', gam_0)

continuation_steps.add_step('bisection') \
    .num_cases(151) \
    .const('theta_f', theta_f)

sol_set = beluga.solve(
    ocp=ocp,
    method='indirect',
    bvp_algorithm=bvp_solver,
    steps=continuation_steps,
    guess_generator=guess_maker,
    optim_options={'control_method': 'differential'},
    initial_helper=True,
    save_sols='hyper_example.beluga',
    autoscale=True
)
Пример #14
0
bvp_solver = beluga.BVPSolver('spbvp')

guess_maker = beluga.GuessGenerator(
    'auto',
    start=[0, 0, 0, 0.01, 60880],  # Starting values for states in order
    costate_guess=-0.1,
    control_guess=[0],
    use_control_guess=False)

beluga.add_logger(file_level=logging.DEBUG, display_level=logging.INFO)

continuation_steps = beluga.ContinuationList()

continuation_steps.add_step('bisection') \
                .num_cases(10) \
                .const('eps', 1) \
                .const('mass_0', 1.1702e5)

continuation_steps.add_step('bisection') \
                .num_cases(10) \
                .const('rho_ref', 1.225)

sol_set = beluga.solve(ocp=ocp,
                       method='indirect',
                       bvp_algorithm=bvp_solver,
                       optim_options={'control_method': 'algebraic'},
                       steps=continuation_steps,
                       guess_generator=guess_maker,
                       autoscale=True)
bvp_solver_indirect = beluga.bvp_algorithm('spbvp')

guess_maker_indirect = beluga.guess_generator(
    'auto',
    start=[3, 5],
    direction='forward',
    costate_guess=-0.1,
    control_guess=[0],
    use_control_guess=True,
    time_integrate=0.1
)

beluga.add_logger(logging_level=logging.DEBUG, display_level=logging.INFO)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
    .num_cases(40, 'log') \
    .const('epsilon1', 2e-4)

sol_set_indirect = beluga.solve(
    ocp=ocp_indirect,
    method='indirect',
    optim_options={'analytical_jacobian': True, 'control_method': 'icrm'},
    bvp_algorithm=bvp_solver_indirect,
    steps=continuation_steps,
    guess_generator=guess_maker_indirect,
    autoscale=False,
    save='indirect_data.blg')
Пример #16
0
    .terminal('y-y_f', 'm')

ocp.scale(m='y', s='y/v', kg=1, rad=1, nd=1)

bvp_solver = beluga.bvp_algorithm('Shooting')

guess_maker = beluga.guess_generator(
    'auto',
    start=[0, 0, 0],  # Starting values for states in order
    costate_guess=-0.1,
    control_guess=[-pi / 2],
    use_control_guess=True)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
                .num_cases(21) \
                .const('x_f', 10) \
                .const('y_f', -10)

beluga.add_logger(logging_level=logging.DEBUG, display_level=logging.INFO)

sol_set = beluga.solve(ocp=ocp,
                       method='diffyg',
                       optim_options={'reduction': True},
                       bvp_algorithm=bvp_solver,
                       steps=continuation_steps,
                       guess_generator=guess_maker,
                       autoscale=False,
                       initial_helper=True)
Пример #17
0
def test_planarhypersonic():
    from math import pi
    import beluga

    ocp = beluga.OCP('planarHypersonic')

    # Define independent variables
    ocp.independent('t', 's')

    # Define equations of motion
    ocp.state('h', 'v*sin(gam)', 'm') \
        .state('theta', 'v*cos(gam)/r', 'rad') \
        .state('v', '-D/mass - mu*sin(gam)/r**2', 'm/s') \
        .state('gam', 'L/(mass*v) + (v/r - mu/(v*r^2))*cos(gam)', 'rad')

    # Define quantities used in the problem
    ocp.quantity('rho', 'rho0*exp(-h/H)')
    ocp.quantity('Cl', '(1.5658*alfa + -0.0000)')
    ocp.quantity('Cd', '(1.6537*alfa^2 + 0.0612)')
    ocp.quantity('D', '0.5*rho*v^2*Cd*Aref')
    ocp.quantity('L', '0.5*rho*v^2*Cl*Aref')
    ocp.quantity('r', 're+h')

    # Define controls
    ocp.control('alfa', 'rad')

    # Define constants
    ocp.constant('mu', 3.986e5 * 1e9, 'm^3/s^2')  # Gravitational parameter, m^3/s^2
    ocp.constant('rho0', 0.0001 * 1.2, 'kg/m^3')  # Sea-level atmospheric density, kg/m^3
    ocp.constant('H', 7500, 'm')  # Scale height for atmosphere of Earth, m

    ocp.constant('mass', 750 / 2.2046226, 'kg')  # Mass of vehicle, kg
    ocp.constant('re', 6378000, 'm')  # Radius of planet, m
    ocp.constant('Aref', pi * (24 * .0254 / 2) ** 2, 'm^2')  # Reference area of vehicle, m^2

    # Define costs
    ocp.terminal_cost('-v^2', 'm^2/s^2')

    # Define constraints
    ocp.constraints() \
        .initial('h-h_0', 'm') \
        .initial('theta-theta_0', 'rad') \
        .initial('v-v_0', 'm/s') \
        .terminal('h-h_f', 'm') \
        .terminal('theta-theta_f', 'rad')

    ocp.scale(m='h', s='h/v', kg='mass', rad=1)

    bvp_solver = beluga.bvp_algorithm('Shooting')

    guess_maker = beluga.guess_generator('auto', start=[80000, 0, 4000, -90 * pi / 180], direction='forward', costate_guess=-0.1)

    continuation_steps = beluga.init_continuation()

    continuation_steps.add_step('bisection') \
        .num_cases(11) \
        .terminal('h', 0) \
        .terminal('theta', 0.01 * pi / 180)

    continuation_steps.add_step('bisection') \
        .num_cases(11) \
        .terminal('theta', 5.0 * pi / 180)

    continuation_steps.add_step('bisection') \
                .num_cases(11) \
                .const('rho0', 1.2)

    sol = beluga.solve(ocp, method='traditional', bvp_algorithm=bvp_solver, steps=continuation_steps, guess_generator=guess_maker)

    y0 = sol.y[0]
    yf = sol.y[-1]

    y0e = [80000, 0, 4000, 0.0195, -16.8243, 1212433.8085, -2836.0620, 0]
    yfe = [0, 0.0873, 2691.4733, -0.9383, 546.4540, 1212433.8085, -5382.9467, 0.1840]
    tfe = 144.5677

    assert sol.t.shape[0] == sol.y.shape[0]
    assert sol.t.shape[0] == sol.u.shape[0]
    assert sol.y.shape[1] == 8
    assert sol.u.shape[1] == 1
    assert abs((y0[0] - y0e[0]) / y0e[0]) < tol
    assert abs((y0[1] - y0e[1])) < tol
    assert abs((y0[2] - y0e[2]) / y0e[2]) < tol
    assert abs((y0[3] - y0e[3]) / y0e[3]) < tol
    assert abs((y0[4] - y0e[4]) / y0e[4]) < tol
    assert abs((y0[5] - y0e[5]) / y0e[5]) < tol
    assert abs((y0[6] - y0e[6]) / y0e[6]) < tol
    assert abs((y0[7] - y0e[7])) < tol
    assert abs((sol.t[-1] - tfe) / tfe) < tol
    assert abs((yf[0] - yfe[0])) < tol
    assert abs((yf[1] - yfe[1]) / yfe[1]) < tol
    assert abs((yf[2] - yfe[2]) / yfe[2]) < tol
    assert abs((yf[3] - yfe[3]) / yfe[3]) < tol
    assert abs((yf[4] - yfe[4]) / yfe[4]) < tol
    assert abs((yf[5] - yfe[5]) / yfe[5]) < tol
    assert abs((yf[6] - yfe[6]) / yfe[6]) < tol
    assert abs((yf[7] - yfe[7]) / yfe[7]) < tol
                                     costate_guess=-0.1)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
                .num_cases(3) \
                .const('v_r_f', 0)

continuation_steps.add_step('bisection') \
                .num_cases(40) \
                .const('t_f', 80)

beluga.add_logger(file_level=logging.DEBUG, display_level=logging.INFO)

sol_set_collocation = beluga.solve(
    ocp=ocp,
    method='indirect',
    bvp_algorithm=bvp_solver_collocation,
    steps=continuation_steps,
    guess_generator=guess_maker,
    save_sols='lowthrust_collocation_data.beluga',
    optim_options={'control_method': 'algebraic'})

sol_set_shooting = beluga.solve(ocp=ocp,
                                method='indirect',
                                bvp_algorithm=bvp_solver_shooting,
                                steps=continuation_steps,
                                guess_generator=guess_maker,
                                save_sols='lowthrust_shooting_data.beluga',
                                optim_options={'control_method': 'algebraic'})
Пример #19
0
def test_brachistochrone_shooting():
    from math import pi
    import beluga

    from beluga.ivpsol import Trajectory
    from beluga.bvpsol import Solution

    ocp = beluga.OCP('brachisto')

    # Define independent variables
    ocp.independent('t', 's')

    # Define equations of motion
    ocp.state('x', 'v*cos(theta)', 'm') \
        .state('y', 'v*sin(theta)', 'm') \
        .state('v', 'g*sin(theta)', 'm/s')

    # Define controls
    ocp.control('theta', 'rad')

    # Define constants
    ocp.constant('g', -9.81, 'm/s^2')

    # Define costs
    ocp.path_cost('1', '1')

    # Define constraints
    ocp.constraints() \
        .initial('x-x_0', 'm') \
        .initial('y-y_0', 'm') \
        .initial('v-v_0', 'm/s') \
        .terminal('x-x_f', 'm') \
        .terminal('y-y_f', 'm')

    ocp.scale(m='y', s='y/v', kg=1, rad=1)

    shooting_solver = beluga.bvp_algorithm('Shooting')

    guess_maker = beluga.guess_generator('auto', start=[0, 0, 0], direction='forward', costate_guess=-0.1, control_guess = [-pi/2], use_control_guess=True)

    continuation_steps = beluga.init_continuation()

    continuation_steps.add_step('bisection') \
        .num_cases(21) \
        .terminal('x', 10) \
        .terminal('y', -10)

    sol = beluga.solve(ocp, method='icrm', bvp_algorithm=shooting_solver, steps=continuation_steps,
                       guess_generator=guess_maker)

    assert isinstance(sol, Trajectory)
    assert isinstance(sol, Solution)
    assert sol.t.shape[0] == sol.y.shape[0]
    assert sol.t.shape[0] == sol.u.shape[0]
    assert sol.y.shape[1] == 7
    assert sol.u.shape[1] == 1

    y0 = sol.y[0]
    yf = sol.y[-1]
    assert abs(y0[0] - 0) < tol
    assert abs(y0[1] - 0) < tol
    assert abs(y0[2] - 0) < tol
    assert abs(y0[3] + 0.0667) < tol
    assert abs(y0[4] - 0.0255) < tol
    assert abs(y0[5] + 0.1019) < tol
    assert abs(sol.t[-1] - 1.8433) < tol
    assert abs(yf[0] - 10) < tol
    assert abs(yf[1] + 10) < tol
    assert abs(yf[2] - 14.0071) < tol
    assert abs(yf[3] + 0.0667) < tol
    assert abs(yf[4] - 0.0255) < tol
    assert abs(yf[5] - 0) < tol
    assert abs(y0[3] - yf[3]) < tol
    assert abs(y0[4] - yf[4]) < tol

    sol = beluga.solve(ocp, method='traditional', bvp_algorithm=shooting_solver, steps=continuation_steps, guess_generator=guess_maker)

    y0 = sol.y[0]
    yf = sol.y[-1]
    assert sol.t.shape[0] == sol.y.shape[0]
    assert sol.t.shape[0] == sol.u.shape[0]
    assert sol.y.shape[1] == 6
    assert sol.u.shape[1] == 1
    assert abs(y0[0] - 0) < tol
    assert abs(y0[1] - 0) < tol
    assert abs(y0[2] - 0) < tol
    assert abs(y0[3] + 0.0667) < tol
    assert abs(y0[4] - 0.0255) < tol
    assert abs(y0[5] + 0.1019) < tol
    assert abs(sol.t[-1] - 1.8433) < tol
    assert abs(yf[0] - 10) < tol
    assert abs(yf[1] + 10) < tol
    assert abs(yf[2] - 14.0071) < tol
    assert abs(yf[3] + 0.0667) < tol
    assert abs(yf[4] - 0.0255) < tol
    assert abs(yf[5] - 0) < tol
    assert abs(y0[3] - yf[3]) < tol
    assert abs(y0[4] - yf[4]) < tol
Пример #20
0
    control_guess=[0],
    use_control_guess=True,
    direction='forward'
)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
                .num_cases(10) \
                .const('x_f', 10)

continuation_steps.add_step('bisection') \
                .num_cases(10) \
                .const('y_f', 10)

continuation_steps.add_step('bisection') \
                .num_cases(10) \
                .const('epsilon', 1)

beluga.add_logger(logging_level=logging.DEBUG, display_level=logging.INFO)

sol_set = beluga.solve(
    ocp=ocp,
    method='indirect',
    optim_options={'control_method': 'icrm'},
    bvp_algorithm=bvp_solver,
    steps=continuation_steps,
    guess_generator=guess_maker,
    initial_helper=True
)
Пример #21
0
beluga.add_logger(file_level=logging.DEBUG, display_level=logging.INFO)

continuation_steps = beluga.ContinuationList()

continuation_steps.add_step('bisection') \
    .num_cases(3) \
    .const('x_0', 0) \
    .const('v_0', 1) \
    .const('x_f', 0) \
    .const('v_f', -1)

continuation_steps.add_step('bisection') \
                .num_cases(10, 'log') \
                .const('x_max', 0.1)

continuation_steps.add_step('bisection') \
                .num_cases(10, 'log') \
                .const('epsilon1', 1e-6)

sol_set_indirect = beluga.solve(ocp=ocp,
                                method='indirect',
                                optim_options={
                                    'analytical_jacobian': False,
                                    'control_method': 'differential'
                                },
                                bvp_algorithm=bvp_solver_indirect,
                                steps=continuation_steps,
                                guess_generator=guess_maker_indirect,
                                autoscale=False,
                                save_sols='indirect_data.json')
Пример #22
0
                    max_error=200
)

guess_maker = beluga.guess_generator('auto',
                start=[0,.01],          # Starting values for states in order
                direction='forward',
                costate_guess = -0.1,
                time_integrate = 1      ## REQUIRED BECAUSE OF FIXED FINAL TIME
)

continuation_steps = beluga.init_continuation()
continuation_steps.add_step('bisection', max_divisions=30).num_cases(5)   \
                    .terminal('x',0) \
                    .initial('v',1) \
                    .terminal('v', -1)

continuation_steps.add_step('activate_constraint', name='xlim')

continuation_steps.add_step('bisection') \
                .num_cases(11) \
                .constraint('xlim', 0.0, index=1)

beluga.setup_beluga(logging_level=logging.DEBUG)

beluga.solve(ocp,
             method='traditional',
             bvp_algorithm=bvp_solver,
             steps=continuation_steps,
             guess_generator=guess_maker
)
Пример #23
0
bvp_solver_shooting = beluga.bvp_algorithm('Shooting', algorithm='Armijo')
bvp_solver_collocation = beluga.bvp_algorithm('spbvp')

guess_maker = beluga.guess_generator('auto',
                                     start=[1, 0, 0, 1, 1],
                                     direction='forward',
                                     costate_guess=-0.1)

continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
                .num_cases(11) \
                .const('v_r_f', 0) \
                .const('t_f', 4)

beluga.add_logger(logging_level=logging.DEBUG, display_level=logging.DEBUG)

sol_set_collocation = beluga.solve(ocp=ocp,
                                   method='indirect',
                                   bvp_algorithm=bvp_solver_collocation,
                                   steps=continuation_steps,
                                   guess_generator=guess_maker,
                                   save='highthrust_collocation_data.blg')

sol_set_shooting = beluga.solve(ocp=ocp,
                                method='indirect',
                                bvp_algorithm=bvp_solver_shooting,
                                steps=continuation_steps,
                                guess_generator=guess_maker,
                                save='highthrust_shooting_data.blg')
Пример #24
0
continuation_steps = beluga.init_continuation()

continuation_steps.add_step('bisection') \
                .num_cases(10, 'log') \
                .const('eps1', 2e-1)

beluga.add_logger(file_level=logging.DEBUG, display_level=logging.INFO)

bvp_solver = beluga.bvp_algorithm('spbvp')

beluga.solve(ocp=ocp,
             method='indirect',
             optim_options={
                 'control_method': 'differential',
                 'analytical_jacobian': True
             },
             bvp_algorithm=bvp_solver,
             steps=continuation_steps,
             guess_generator=guess_maker,
             autoscale=False,
             save_sols='indirect_data.beluga')

# bvp_solver = beluga.bvp_algorithm('Collocation', num_nodes=60)

# beluga.solve(ocp=ocp,
#              method='direct',
#              bvp_algo=bvp_solver,
#              steps=None,
#              guess_gen=guess_maker,
#              autoscale=False,
#              save_sols='direct_data.blg')
Пример #25
0
def test_zermelo_custom_functions():
    import beluga

    ocp = beluga.OCP('zermelos_problem')

    def drift_x(x, y):
        return 0

    def drift_y(x, y):
        return ((x - 5)**4 - 625) / 625

    ocp.custom_function('drift_x', drift_x)
    ocp.custom_function('drift_y', drift_y)

    # Define independent variables
    ocp.independent('t', 's')

    # Define equations of motion
    ocp.state('x', 'V*cos(theta) + epsilon*drift_x(x,y)', 'm') \
        .state('y', 'V*sin(theta) + epsilon*drift_y(x,y)', 'm')

    # Define controls
    ocp.control('theta', 'rad')

    # Define constants
    ocp.constant('V', 10, 'm/s')
    ocp.constant('epsilon', 0.001, '1')
    ocp.constant('x_f', 0, 'm')
    ocp.constant('y_f', 0, 'm')

    # Define costs
    ocp.path_cost('1', '1')

    # Define constraints
    ocp.constraints() \
        .initial('x', 'm') \
        .initial('y', 'm') \
        .terminal('x-x_f', 'm') \
        .terminal('y-y_f', 'm')

    ocp.scale(m='x', s='x/V', rad=1)

    bvp_solver = beluga.bvp_algorithm('Shooting',
                                      derivative_method='fd',
                                      tolerance=1e-4,
                                      max_error=100,
                                      max_iterations=100)

    guess_maker = beluga.guess_generator('auto',
                                         start=[0, 0],
                                         control_guess=[0],
                                         use_control_guess=True,
                                         direction='forward')

    continuation_steps = beluga.init_continuation()

    continuation_steps.add_step('bisection') \
        .num_cases(10) \
        .const('x_f', 10)

    continuation_steps.add_step('bisection') \
        .num_cases(10) \
        .const('y_f', 10)

    continuation_steps.add_step('bisection') \
        .num_cases(10) \
        .const('epsilon', 1)

    sol = beluga.solve(ocp,
                       method='icrm',
                       bvp_algorithm=bvp_solver,
                       steps=continuation_steps,
                       guess_generator=guess_maker)

    from beluga.ivpsol import Trajectory
    assert isinstance(sol, Trajectory)