def caps_all_anodes(tempdatetime):
et = spice.datetime2et(tempdatetime)
sclkdp = spice.sce2c(
-82, et) # converts an et to a continuous encoded sc clock (ticks)
caps_els_anode_vecs = []
for anodenumber, x in enumerate(np.arange(70, -90, -20)):
# print(anodenumber, x)
rotationmatrix_anode = spice.spiceypy.axisar(np.array(
[1, 0, 0]), x * spice.rpd()) # Get angles for different anodes
# print("rotationmatrix_anode", rotationmatrix_anode)
postanode_rotation = spice.vhat(
spice.mxv(rotationmatrix_anode, -spice.spiceypy.getfov(
-82821, 20)[2])) # Apply rotation for anodes
# print("postanode_rotation", postanode_rotation)
# print("caps_els_boresight", caps_els_boresight)
cassini_caps_mat = spice.ckgp(
-82821, sclkdp, 0, 'CASSINI_CAPS_BASE')[0] # Get actuation angle
# print("cassini_caps_mat", cassini_caps_mat)
cassini_caps_act_vec = spice.mxv(
cassini_caps_mat, postanode_rotation) # Rotate with actuator
# print("Actuating frame", cassini_caps_act_vec)
CAPS_act_2_titan_cmat = spice.ckgp(
-82000, sclkdp, 0,
'IAU_TITAN')[0] # Find matrix to transform to IAU_TITAN frame
CAPS_act_2_titan_cmat_transpose = spice.xpose(
CAPS_act_2_titan_cmat) # Tranpose matrix
rotated_vec = spice.mxv(CAPS_act_2_titan_cmat_transpose,
cassini_caps_act_vec) # Apply Matrix
# print("rotated_vec ", rotated_vec)
caps_els_anode_vecs.append(rotated_vec)
return caps_els_anode_vecs
def convert_to_inst(self, coords):
"""
Convert the given coordinates to the instrument frame
Parameters
----------
coords : `astropy.coordinate.SkyCoord`
The coordinates to transform to the instrument frame
frame : `str`, optional
The instrument coordinate frame (ILS or OPT)
Returns
-------
tuple
x and y coordinates
"""
icrs_coords = coords.transform_to('icrs')
cart_coords = icrs_coords.represent_as('cartesian')
et = spiceypy.datetime2et(coords.obstime.to_datetime())
sc = spiceypy.sce2c(SOLAR_ORBITER_ID, et)
cmat, sc = spiceypy.ckgp(SOLAR_ORBITER_STIX_ILS_FRAME_ID, sc, 0, 'J2000')
vec = cmat @ cart_coords.xyz.value
# Rotate about z so +x towards the Sun
# vec = np.array([[-1, 0, 0], [0, -1, 0], [0, 0, 1]]) @ vec
distance, latitude, longitude = spiceypy.reclat(vec.reshape(3))
y = (latitude + np.pi) * u.rad
x = (np.pi/2 - longitude) * u.rad
return x, y
def find_cmatrix(ets_in):
"""find list of c-matrices given ephemeris times and time errors"""
obs="-143"
ref="J2000"
inst = int(obs) * 1000
matrices = []
sctol = sp.sctiks(int(obs), SPICE_TOLERANCE)
for et in ets_in:
scticks = sp.sce2c(int(obs), et)
[matrix, sc_time] = sp.ckgp(inst, scticks, sctol, ref)
matrices.append(matrix)
return matrices
def getCameraMatrix(frame, spacecraft, instrument, ephemerisTime):
"""
Get camera pointing matrix C.
This is the world-to-camera matrix, from the base frame to the
given instrument's fixed frame at the given ephemeris time.
"""
sclkdp = spice.sce2c(spacecraft, ephemerisTime) # spacecraft clock double
# sclkch = spice.sce2s(spacecraft, ephemerisTime) # spacecraft clock string
# print 'sclkdp',sclkdp
# see https://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/ckgp_c.html
tolerance = spice.sctiks(spacecraft, "0:00:800") # time tolerance
C, clkout, found = spice.ckgp(instrument, sclkdp, tolerance, frame)
if not found:
print 'camera pointing matrix not found for time', sclkdp
# continue
C = None
return C
def cassini_ramdirection_SCframe(tempdatetime, target='CASSINI', frame='J2000', observ='titan', corrtn='NONE',
output=False):
et = spice.datetime2et(tempdatetime)
state, ltime = spice.spkezr(target, et, frame, corrtn, observ)
ramdir = spice.vhat(state[3:6])
# Gets Attitude
sclkdp = spice.sce2c(-82, et) # converts an et to a continuous encoded sc clock (ticks)
ckgp_output = spice.ckgp(-82000, sclkdp, 0, frame)
cmat = ckgp_output[0]
ram_unit = spice.mxv(cmat, ramdir)
if output:
print('ET = {:20.6f}'.format(et))
print('VX = {:20.6f}'.format(ram_unit[0]))
print('VY = {:20.6f}'.format(ram_unit[1]))
print('VZ = {:20.6f}'.format(ram_unit[2]))
return ram_unit
def caps_crosstrack(tempdatetime, windspeed):
et = spice.datetime2et(tempdatetime)
state, ltime = spice.spkezr("CASSINI", et, "IAU_TITAN", "NONE", "titan")
ramdir = spice.vhat(state[3:6])
# print("ramdir",ramdir)
# Gets Attitude
sclkdp = spice.sce2c(
-82, et) # converts an et to a continuous encoded sc clock (ticks)
ckgp_output = spice.ckgp(-82000, sclkdp, 0, "IAU_TITAN")
cmat = ckgp_output[0]
spacecraft_axis = np.array([0, 0, 1])
rotated_spacecraft_axis = spice.mxv(cmat, spacecraft_axis)
# print("cmat", cmat)
# print("rotated spacecraft axis",rotated_spacecraft_axis)
ram_unit = spice.mxv(cmat, -ramdir) # Ram Unit in SC coords
# print("ram_unit",ram_unit)
if windspeed < 0:
rotationmatrix = spice.axisar(np.array([0, 0, -1]), 90 * spice.rpd())
if windspeed > 0:
rotationmatrix = spice.axisar(np.array([0, 0, -1]), -90 * spice.rpd())
# print(rotationmatrix)
crossvec = spice.mxv(
rotationmatrix,
ram_unit) # Rotate ram unit to find crosstrack velocity vector
# print("temp crossvec",crossvec)
# print("vsep SC Frame",spice.vsep(ram_unit,crossvec)*spice.dpr())
cmat_t = spice.xpose(cmat)
crossvec_titan = spice.mxv(cmat_t,
crossvec) # Transform back to IAU Titan Frame
# print("crossvec", crossvec)
# print("crossvec_titan", crossvec_titan, spice.unorm(crossvec_titan))
# print("vsep titan frame", spice.vsep(ramdir, crossvec_titan) * spice.dpr())
return crossvec_titan
def get_orientation(self, date, frame):
"""
Get the orientation or roll, pith and yaw of STIX (ILS or OPT).
Parameters
----------
date : `datetime.datetime`
Date at which to obtain orientation information
frame : `str`
Name of the coordinate frame
Returns
-------
tuple
Roll, pitch and yaw of the spacecraft
"""
et = spiceypy.datetime2et(date)
sc = spiceypy.sce2c(SOLAR_ORBITER_ID, et)
cmat, sc = spiceypy.ckgp(SOLAR_ORBITER_SRF_FRAME_ID, sc, 0, frame)
vec = cmat @ np.eye(3)
roll, pitch, yaw = spiceypy.m2eul(vec, 1, 2, 3)
roll, pitch, yaw = np.rad2deg([roll, pitch, yaw])*u.deg
return roll, pitch, yaw
def getTargetPosition(target, craft, camera, time):
"""
get position of target in world coordinates relative to the observing craft.
"""
# get target code
targetId = spice.bodn2c(target) # eg 'Jupiter'->599
# get spacecraft instrument
spacecraft = -31 if craft=='Voyager1' else -32
spacecraftBus = spacecraft * 1000
spacecraftScanPlatform = spacecraftBus - 100
spacecraftNarrowCamera = spacecraftScanPlatform - 1
spacecraftWideCamera = spacecraftScanPlatform - 2
# instrument = spacecraftBus # use for NAIF continuous kernels
instrument = spacecraftScanPlatform # use for PDS discrete kernels
# get ephemeris time
# note: target and spacecraft locations are stored relative to J2000
# time is utc time as string
ephemerisTime = spice.str2et(time) # seconds since J2000 (will be negative)
# sclkch = spice.sce2s(spacecraft, ephemerisTime) # spacecraft clock ticks, string
# sclkdp = spice.sce2c(spacecraft, ephemerisTime) # spacecraft clock ticks, double
clockTicks = spice.sce2c(spacecraft, ephemerisTime) # spacecraft clock ticks, double
# print 'clockTicks',clockTicks
# get position of target relative to spacecraft
# this is the direction from craft to target in ECLIPB1950 frame
observer = 'Voyager ' + craft[-1] # eg 'Voyager 1'
frame = 'ECLIPB1950' # coordinate frame
abberationCorrection = 'NONE'
position, lightTime = spice.spkpos(target, ephemerisTime, frame,
abberationCorrection, observer)
# print 'target position relative to observer', position
return position
def caps_crosstrack_spice(tempdatetime, windspeed):
et = spice.datetime2et(tempdatetime)
sclkdp = spice.sce2c(
-82, et) # converts an et to a continuous encoded sc clock (ticks)
state, ltime = spice.spkezr("CASSINI", et, "IAU_TITAN", "NONE", "titan")
ramdir = spice.vhat(state[3:6])
# print("ramdir",ramdir)
# Gets Attitude
sclkdp = spice.sce2c(
-82, et) # converts an et to a continuous encoded sc clock (ticks)
ckgp_output = spice.ckgp(-82000, sclkdp, 0, "IAU_TITAN")
cmat = ckgp_output[0]
print("cmat", cmat)
ram_unit = spice.mxv(cmat, ramdir) # Ram Unit in SC coords
# print("ram_unit", ram_unit)
anglediff = spice.vsepg(
ram_unit[:2], np.array([0, 1, 0]),
2) # Find azimuthal angle between normal boresight and ram direction
# print("anglediff", anglediff * spice.dpr())
cassini_ram_mat = spice.rotate(-anglediff, 3)
# print("cassini_ram_mat", cassini_ram_mat)
# Rotates rotational axis with actuation
# cassini_caps_mat = spice.ckgp(-82821, sclkdp, 0, 'CASSINI_CAPS_BASE')[0] # Rotation matrix of actuation
# print("cassini_caps_mat", cassini_caps_mat)
anode_rotational_axis = spice.mxv(cassini_ram_mat,
np.array([1, 0,
0])) # Rotate with actuator
print("Rotational Axis", anode_rotational_axis)
rotationmatrix_1 = spice.spiceypy.axisar(anode_rotational_axis,
-70 * spice.rpd())
rotationmatrix_2 = spice.spiceypy.axisar(anode_rotational_axis,
70 * spice.rpd())
ram_unit_rotated1 = spice.mxv(rotationmatrix_1, ram_unit)
ram_unit_rotated2 = spice.mxv(rotationmatrix_2, ram_unit)
scframe_spiceplane = spice.psv2pl([0, 0, 0], ram_unit_rotated1,
ram_unit_rotated2)
print("ram_unit", ram_unit, ram_unit_rotated1, ram_unit_rotated2)
print("SC frame spice normal",
spice.psv2pl([0, 0, 0], ram_unit_rotated1, ram_unit_rotated2))
cmat_t = spice.xpose(cmat)
ram_unit_rotated1_titan = spice.mxv(
cmat_t, ram_unit_rotated1) # Transform back to IAU Titan Frame
ram_unit_rotated2_titan = spice.mxv(
cmat_t, ram_unit_rotated2) # Transform back to IAU Titan Frame
spiceplanenormal = spice.mxv(cmat_t, spice.pl2nvp(scframe_spiceplane)[0])
# Old method finding normal in titan frame
# spiceplane = spice.psv2pl(state[:3], ram_unit_rotated1_titan, ram_unit_rotated2_titan)
# spiceplanenormal = spice.pl2nvp(spiceplane)[0]
print("SPICE NORMAL", spiceplanenormal)
# print("Spice normal, sc frame", scframe_spicenormal_titan)
if windspeed > 0:
spiceplanenormal = -1 * spiceplanenormal
print("spice plane fipped", windspeed, spiceplanenormal)
print("vsep titan frame",
spice.vsep(ramdir, spiceplanenormal) * spice.dpr())
return spiceplanenormal, ram_unit_rotated1_titan, ram_unit_rotated2_titan
def get_orientation(dt, frame1='SOLO_SRF', frame2='SOLO_EQUAT_NORM'):
"""
Get the orientation or roll, pith and yaw of STIX (ILS or OPT).
Taken from https://github.com/i4Ds/STIXCore/blob/9a765a33f2e924ead669b9b99afc1e41a4d2d8e8/stixcore
/ephemeris/tests/test_position.py#L28-L40
Parameters
----------
date : `datetime.datetime`
Date at which to obtain orientation information
frame : `str`
Name of the coordinate frame
Returns
-------
tuple
Roll, pitch and yaw of the spacecraft
SOLO mission specific generic frames:
SOLO_SUN_RTN Sun Solar Orbiter Radial-Tangential-Normal
SOLO_SOLAR_MHP S/C-centred mirror helioprojective
SOLO_IAU_SUN_2009 Sun Body-Fixed based on IAU 2009 report
SOLO_IAU_SUN_2003 Sun Body-Fixed based on IAU 2003 report
SOLO_GAE Geocentric Aries Ecliptic at J2000 (GAE)
SOLO_GSE Geocentric Solar Ecliptic at J2000 (GSE)
SOLO_HEE Heliocentric Earth Ecliptic at J2000 (HEE)
SOLO_VSO Venus-centric Solar Orbital (VSO)
Heliospheric Coordinate Frames developed for the NASA STEREO mission:
SOLO_ECLIPDATE Mean Ecliptic of Date Frame
SOLO_HCI Heliocentric Inertial Frame
SOLO_HEE_NASA Heliocentric Earth Ecliptic Frame
SOLO_HEEQ Heliocentric Earth Equatorial Frame
SOLO_GEORTN Geocentric Radial Tangential Normal Frame
Heliocentric Generic Frames(*):
SUN_ARIES_ECL Heliocentric Aries Ecliptic (HAE)
SUN_EARTH_CEQU Heliocentric Earth Equatorial (HEEQ)
SUN_EARTH_ECL Heliocentric Earth Ecliptic (HEE)
SUN_INERTIAL Heliocentric Inertial (HCI)
Geocentric Generic Frames:
EARTH_SUN_ECL (*) Geocentric Solar Ecliptic (GSE)
EARTH_MECL_MEQX (*) Earth Mean Ecliptic and Equinox of date
frame (Auxiliary frame for EARTH_SUN_ECL)
EARTH_MECL_MEQX_J2000 Earth Mean Ecliptic and Equinox at J2000
frame (Auxiliary frame for SOLO_GSE and
SOLO_HEE)
"""
et = sp.datetime2et(dt)
sc = sp.sce2c(SOLAR_ORBITER_ID, et) #convert to clock ticks
#tol=sp.sctiks(int(sc), "1:000")
tol= 1.0
#cmat, sc= sp.ckgp(SOLAR_ORBITER_SRF_FRAME_ID, sc, tol, 'SOLO_ECLIP_NORM')
#cmat, sc= sp.ckgp(SOLAR_ORBITER_SRF_FRAME_ID, sc, tol, 'SOLO_EQUAT_NORM')
frame_id=SOLAR_ORBITER_SRF_FRAME_ID if frame1=='SOLO_SRF' else SOLAR_ORBITER_STIX_OPT_FRAME_D
cmat, sc= sp.ckgp(frame_id, sc, tol, frame2)
#get c-matrix orientiation information
roll, pitch, yaw = sp.m2eul(cmat, 1, 2, 3)
#matrix to Euler angles
# Following lines taken from from get_sunspice_roll.pro
#https://www.heliodocs.com/xdoc/xdoc_list.php?dir=$SSW/packages/sunspice/idl
#if abs(roll) > 2 *math.pi:
# roll=roll-math.copysign(2*math.pi,roll)
#if abs(pitch) > 0.5* math.pi:
# #taken from idl code get_sunspice_roll.pro
# pitch = math.copysign(2*math.pi, pitch) - pitch
# yaw = yaw - math.copysign(2*math.pi, yaw)
# roll = roll - math.copysign(2*math.pi, roll)
roll, pitch, yaw = np.rad2deg([roll, pitch, yaw])#convert to arcmin
#take from Frederic idl code
#if yaw <0:
# yaw+=360
#yaw = yaw-180
pitch = -pitch
roll = -roll
return (roll, pitch, yaw)
def getCameraMatrix(craft, camera, time):
"""
get the camera matrix for the given craft and camera at a utc time.
assumes libimg.loadKernels has been called.
returns C, the 3x3 rotation matrix as a numpy array.
"""
# get target code
# targetId = spice.bodn2c(target) # eg 'Jupiter'->599
# get spacecraft instrument
spacecraft = -31 if craft=='Voyager1' else -32
spacecraftBus = spacecraft * 1000
spacecraftScanPlatform = spacecraftBus - 100
spacecraftNarrowCamera = spacecraftScanPlatform - 1
spacecraftWideCamera = spacecraftScanPlatform - 2
# instrument = spacecraftBus # use for NAIF continuous kernels
instrument = spacecraftScanPlatform # use for PDS discrete kernels
# get field of view and focal length
# f is the focal length relative to the screen halfwidth of 1.0
# i.e. screen coordinates are -1.0 to 1.0
#. use ik
# print 'camera',camera
fov = config.cameraFOVs[camera] # degrees - 0.424 or 3.169
screenHalfwidth = 1.0
f = screenHalfwidth / math.tan(fov/2 * math.pi/180)
# print 'f=focal length',f
# get ephemeris time
# note: target and spacecraft locations are stored relative to J2000
# time is utc time as string
ephemerisTime = spice.str2et(time) # seconds since J2000 (will be negative)
# sclkch = spice.sce2s(spacecraft, ephemerisTime) # spacecraft clock ticks, string
# sclkdp = spice.sce2c(spacecraft, ephemerisTime) # spacecraft clock ticks, double
clockTicks = spice.sce2c(spacecraft, ephemerisTime) # spacecraft clock ticks, double
# print 'clockTicks',clockTicks
# # get position of target relative to spacecraft
# # this is the direction from craft to target in ECLIPB1950 frame
# observer = 'Voyager ' + craft[-1] # eg 'Voyager 1'
# frame = 'ECLIPB1950' # coordinate frame
# abberationCorrection = 'NONE'
# position, lightTime = spice.spkpos(target, ephemerisTime, frame,
# abberationCorrection, observer)
# print 'target position relative to observer', position
# get camera pointing matrix C
# C is the world-to-camera transformation matrix.
# ie C is a rotation matrix from the base frame 'frame' to
# the instrument-fixed frame at the time clockTicks +/- tolerance.
# https://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/ckgp_c.html
tolerance = spice.sctiks(spacecraft, "0:00:800") # time tolerance
frame = 'ECLIPB1950' # coordinate frame
# ckgp is 'camera kernel get pointing'
# note: the pointing information is stored in the time frame J2000,
# but the coordinates are in the ECLIPB1950 coordinate frame.
C, clkout, found = spice.ckgp(instrument, clockTicks, tolerance, frame)
# print 'C=camera pointing matrix - transform world to camera coords'
# print C
return C