def compare_perturbers_orekit():
f, ax = plt.subplots(2, 1)
sv, _, _ = over.read_poe(
'data/S1A_OPER_AUX_POEORB_OPOD_20150527T122640_V20150505T225944_20150507T005944.EOF'
)
trySentinel1_compare(
ax,
sv,
'no solarsystem perturbers',
C_D=2.3,
C_R=1.0,
radiation_pressure=True,
solarsystem_perturbers=[],
)
trySentinel1_compare(
ax,
sv,
'Moon + sun perturbers',
C_D=2.3,
C_R=1.0,
radiation_pressure=True,
solarsystem_perturbers=['Moon', 'Sun'],
)
ax[0].set_title(
'Errors from propagation: Third body perturbations comparison')
ax[0].set_ylabel('Position error [m]')
ax[1].set_ylabel('Velocity error [m/s]')
ax[1].set_xlabel('Time [h]')
ax[0].legend()
plt.show()
def compare_grav_orekit():
f, ax = plt.subplots(2, 1)
sv, _, _ = over.read_poe(
'data/S1A_OPER_AUX_POEORB_OPOD_20150527T122640_V20150505T225944_20150507T005944.EOF'
)
trySentinel1_compare(
ax,
sv,
'Newtonian grav',
C_D=2.3,
C_R=1.0,
radiation_pressure=True,
earth_gravity='Newtonian',
)
trySentinel1_compare(
ax,
sv,
'HolmesFeatherstone grav',
C_D=2.3,
C_R=1.0,
radiation_pressure=True,
earth_gravity='HolmesFeatherstone',
)
ax[0].set_title('Errors from propagation: gravity model')
ax[0].set_ylabel('Position error [m]')
ax[1].set_ylabel('Velocity error [m/s]')
ax[1].set_xlabel('Time [h]')
ax[0].legend()
plt.show()
def compare_C_D_orekit():
sv, _, _ = over.read_poe(
'data/S1A_OPER_AUX_POEORB_OPOD_20150527T122640_V20150505T225944_20150507T005944.EOF'
)
N = len(sv)
t = 10 * np.arange(N)
f, ax = plt.subplots(2, 1)
trySentinel1_compare(
ax,
sv,
'C_D = 1.6',
C_D=1.6,
C_R=1.0,
radiation_pressure=True,
)
pv = trySentinel1_compare(
ax,
sv,
'C_D = 2.3',
C_D=2.3,
C_R=1.0,
radiation_pressure=True,
)
trySentinel1_compare(
ax,
sv,
'C_D = 3.0',
C_D=3.0,
C_R=1.0,
radiation_pressure=True,
)
ax[0].set_title('Errors from propagation: drag coefficient comparison')
ax[0].set_ylabel('Position error [m]')
ax[1].set_ylabel('Velocity error [m/s]')
ax[1].set_xlabel('Time [h]')
'''
ax2 = ax[0].twinx()
ax2.plot(t/3600., np.linalg.norm(pv[:3].T, axis=1), 'b.', alpha=0.25)
ax2.set_ylabel('Orbital radius', color='b')
ax2.tick_params('y', colors='b')
'''
f.tight_layout()
ax[0].legend()
plt.show()
def compare_effects_orekit():
f, ax = plt.subplots(2, 1)
sv, _, _ = over.read_poe(
'data/S1A_OPER_AUX_POEORB_OPOD_20150527T122640_V20150505T225944_20150507T005944.EOF'
)
trySentinel1_compare(
ax,
sv,
'No tidal, No PR',
C_D=2.3,
C_R=1.0,
frame_tidal_effects=False,
radiation_pressure=False,
)
trySentinel1_compare(
ax,
sv,
'No tidal, PR',
C_D=2.3,
C_R=1.0,
frame_tidal_effects=False,
radiation_pressure=True,
)
trySentinel1_compare(
ax,
sv,
'Tidal, PR',
C_D=2.3,
C_R=1.0,
frame_tidal_effects=True,
radiation_pressure=True,
)
ax[0].set_title('Errors from propagation: tidal and radiation effect')
ax[0].set_ylabel('Position error [m]')
ax[1].set_ylabel('Velocity error [m/s]')
ax[1].set_xlabel('Time [h]')
ax[0].legend()
plt.show()
def trySentinel1(**kw):
p = PropagatorOrekit(
in_frame='ITRF',
out_frame='ITRF',
frame_tidal_effects=True,
#earth_gravity='Newtonian',
#radiation_pressure=False,
#solarsystem_perturbers=[],
#drag_force=False,
)
sv, _, _ = over.read_poe(
'data/S1A_OPER_AUX_POEORB_OPOD_20150527T122640_V20150505T225944_20150507T005944.EOF'
)
x, y, z = sv[0].pos
vx, vy, vz = sv[0].vel
mjd0 = (sv[0]['utc'] - np.datetime64('1858-11-17')) / np.timedelta64(
1, 'D')
N = len(sv)
t = 10 * np.arange(N)
kwargs = dict(m=2300., C_R=0., C_D=.0, A=4 * 2.3)
kwargs.update(**kw)
pv = p.get_orbit_cart(t, x, y, z, vx, vy, vz, mjd0, **kwargs)
perr = np.linalg.norm(pv[:3].T - sv.pos, axis=1)
verr = np.linalg.norm(pv[3:].T - sv.vel, axis=1)
f, ax = plt.subplots(2, 1)
ax[0].plot(t / 3600., perr)
ax[0].set_title('Errors from propagation')
ax[0].set_ylabel('Position error [m]')
ax[1].plot(t / 3600., verr)
ax[1].set_ylabel('Velocity error [m/s]')
ax[1].set_xlabel('Time [h]')
o_nept = dict()
p_orekit = PropagatorOrekit
o_orekit = dict(
in_frame='TEME',
out_frame='ITRF',
)
props = [
(p_sgp4, o_sgp4),
(p_nept, o_nept),
# (p_orekit,o_orekit),
]
# wtf is this?
sv, _, _ = over.read_poe(
'data/S1A_OPER_AUX_POEORB_OPOD_20150527T122640_V20150505T225944_20150507T005944.EOF'
)
sv = sv[:8641]
x, y, z = sv[0].pos / 1e3
vx, vy, vz = sv[0].vel / 1e3
mjd0 = (sv[0]['utc'] - np.datetime64('1858-11-17')) / np.timedelta64(1, 'D')
_alph = 0.75
N = len(sv)
t = 10 * np.arange(N)
fig, axs = plt.subplots(2, 1)
def trySentinel1_array(**kw):
p = PropagatorOrekit(
in_frame='ITRF',
out_frame='ITRF',
frame_tidal_effects=True,
#earth_gravity='Newtonian',
#radiation_pressure=False,
#solarsystem_perturbers=[],
#drag_force=False,
)
sv, _, _ = over.read_poe(
'data/S1A_OPER_AUX_POEORB_OPOD_20150527T122640_V20150505T225944_20150507T005944.EOF'
)
x, y, z = sv[0].pos
vx, vy, vz = sv[0].vel
mjd0 = (sv[0]['utc'] - np.datetime64('1858-11-17')) / np.timedelta64(
1, 'D')
N = len(sv)
t = 10 * np.arange(N)
num = []
for _, item in kw.items():
num.append(len(item))
num = np.sum(num) / float(len(num))
if np.abs(num - np.round(num)) < 1e-9:
num = int(num)
else:
raise Exception('All vectors not equal length')
perr = np.empty((N, num), dtype=np.float64)
verr = np.empty((N, num), dtype=np.float64)
kwargs = dict(m=2300., C_R=0., C_D=.0, A=4 * 2.3)
comm = MPI.COMM_WORLD
rank = comm.rank
pool = comm.size
my_range = list(range(rank, num, pool))
for place, ind in enumerate(my_range):
print('PID{}: {}/{} orbits done'.format(rank, place, len(my_range)))
for key, item in kw.items():
kwargs.update({key: item[ind]})
pv = p.get_orbit_cart(t, x, y, z, vx, vy, vz, mjd0, **kwargs)
perr[:, ind] = np.linalg.norm(pv[:3].T - sv.pos, axis=1)
verr[:, ind] = np.linalg.norm(pv[3:].T - sv.vel, axis=1)
if pool > 1:
if rank == 0:
print(
'---> Thread {}: Receiving all results <barrier>'.format(rank))
for T in range(1, pool):
for ind in range(T, num, pool):
perr[:, ind] = comm.recv(source=T, tag=ind)
verr[:, ind] = comm.recv(source=T, tag=ind * 10)
else:
print(
'---> Thread {}: Distributing all filter results to thread 0 <barrier>'
.format(rank))
for ind in my_range:
comm.send(perr[:, ind], dest=0, tag=ind)
comm.send(verr[:, ind], dest=0, tag=ind * 10)
print('---> Distributing done </barrier>')
if rank == 0:
f, ax = plt.subplots(2, 1)
for ind in range(num):
ax[0].plot(t / 3600., perr[:, ind], '-b', alpha=0.01)
ax[1].plot(t / 3600., verr[:, ind], '-b', alpha=0.01)
ax[0].set_title('Errors from propagation')
ax[0].set_ylabel('Position error [m]')
ax[1].set_ylabel('Velocity error [m/s]')
ax[1].set_xlabel('Time [h]')
plt.show()