def fitness(self, x):
obj1 = 0
transfer = hodographicShaping(
self.scStateDep,
self.scStateArr,
departureDate=self.depDate,
tof=self.tof,
N=self.N,
departureBody=self.depBody,
arrivalBody=self.target,
rShape='CPowPow2_scaled',
thetaShape='CPowPow2_scaled',
zShape='CosR5P3CosR5P3SinR5_scaled',
rShapeFree='PSin05PCos05_scaled',
thetaShapeFree='PSin05PCos05_scaled',
zShapeFree='P4CosR5P4SinR5_scaled',
rFreeC=[x[0], x[1]],
thetaFreeC=[x[2], x[3]],
zFreeC=[x[4], x[5]],
)
transfer.shapingRadial()
transfer.shapingVertical()
transfer.shapingTransverse()
transfer.assembleThrust()
transfer.evaluate(evalThrust=False)
obj1 = transfer.deltaV
return [
obj1,
]
def boundaryConditionComparison():
# trajectory settings
depMjd = 3421
tof = 349
N = 1
arrMjd = depMjd + tof
depBody = '3'
arrBody = '4'
ephems = 'spice'
# departure and arrival states: rendezvous
scStateDep, __, __ = ephemeris(depBody, depMjd, mode=ephems)
scStateArr, __, __ = ephemeris(arrBody, arrMjd, mode=ephems)
transfer = hodographicShaping(scStateDep, scStateArr)
transfer.shapingRadial()
transfer.shapingVertical()
transfer.shapingTransverse()
transfer.assembleThrust()
transfer.checkBoundaryConditions()
if transfer.velCompare == True and transfer.posCompare == True:
print('OK\tBoundary conditions comparison (built-in)')
else:
print('ERROR\tBoundary conditions comparison (built-in)')
def fullTest2(rtol = 1e-3, atol = 1e-2):
# trajectory settings
depMjd = 10025
tof = 1050
N = 2
arrMjd = depMjd + tof
depBody = 'earth'
arrBody = 'mars'
# departure and arrival states: rendezvous
scStateDep, __, __ = ephemeris(depBody, depMjd)
scStateArr, __, __ = ephemeris(arrBody, arrMjd)
transfer = hodographicShaping(scStateDep, scStateArr,
departureDate=depMjd, tof=tof, N=N,
departureBody = depBody,
arrivalBody = arrBody,
rShape = 'CPowPow2_scaled',
thetaShape = 'CPowPow2_scaled',
zShape = 'CosR5P3CosR5P3SinR5_scaled',
rShapeFree = 'PSin05PCos05_scaled',
thetaShapeFree = 'PSin05PCos05_scaled',
zShapeFree = 'P4CosR5P4SinR5_scaled',
rFreeC = [0, 0],
thetaFreeC = [0, 0],
zFreeC = [0, 0],
)
transfer.shapingRadial()
transfer.shapingVertical()
transfer.shapingTransverse()
transfer.assembleThrust()
transfer.checkBoundaryConditions()
transfer.evaluate(evalThrust='Grid', printTime=False, nEvalPoints = 1000)
testPoints = [transfer.psiTransfer, transfer.deltaV, transfer.maxThrust]
# print(testPoints)
knownPoints = [2.573118029750549, 6338.852298544599, 0.00015143346642256032]
test = np.allclose(testPoints, knownPoints, rtol, atol)
if test == True:
print('OK\tFull test 2 (earth-mars, departureDate=10025,',
'tof=1050, N=2)')
else:
print('ERROR\tFull test 2 (earth-mars, departureDate=10025,',
'tof=1050, N=2)')
print('\tComputed: ', testPoints)
print('\tExpected: ', knownPoints)
def fullTest3(rtol = 1e-3, atol = 1e-2):
# trajectory settings
depMjd = 12000
tof = 300
N = 1
arrMjd = depMjd + tof
depBody = 'earth'
arrBody = 'venus'
# departure and arrival states: rendezvous
scStateDep, __, __ = ephemeris(depBody, depMjd)
scStateArr, __, __ = ephemeris(arrBody, arrMjd)
transfer = hodographicShaping(scStateDep, scStateArr,
departureDate=depMjd, tof=tof, N=N,
departureBody = depBody,
arrivalBody = arrBody,
rShape = 'CPowPow2_scaled',
thetaShape = 'CPowPow2_scaled',
zShape = 'CPowPow2_scaled',
rShapeFree = 'PSin05PCos05_scaled',
thetaShapeFree = 'PSin05PCos05_scaled',
zShapeFree = 'P4CosR5P4SinR5_scaled',
rFreeC = [2, 20000],
thetaFreeC = [173, 3460],
zFreeC = [1990, 3333],
)
transfer.shapingRadial()
transfer.shapingVertical()
transfer.shapingTransverse()
transfer.assembleThrust()
transfer.checkBoundaryConditions()
transfer.evaluate(evalThrust='Grid', printTime=False, nEvalPoints = 1000)
testPoints = [transfer.psiTransfer, transfer.deltaV, transfer.maxThrust]
# print(testPoints)
knownPoints = [0.71804214972971, 22535.748458173402, 0.0012091070214979359]
test = np.allclose(testPoints, knownPoints, rtol, atol)
if test == True:
print('OK\tFull test 3 (earth-venus, departureDate=12000,',
'tof=300, N=1)')
else:
print('ERROR\tFull test 3 (earth-venus, departureDate=12000,',
'tof=300, N=1)')
print('\tComputed: ', testPoints)
print('\tExpected: ', knownPoints)
def fitness(self, x):
obj = 0
transfer = hodographicShaping('earth',
'mars',
departureDate=x[0],
tof=x[1],
N=x[2])
transfer.shapingRadial()
transfer.shapingVertical()
transfer.shapingTransverse()
transfer.assembleThrust()
transfer.evaluate(evalThrust=False)
obj = transfer.deltaV
return [
obj,
]
def fitness(self, x):
obj1, obj2 = 0, 0
transfer = hodographicShaping('earth',
'mars',
departureDate=x[0],
tof=x[1],
N=x[2])
transfer.shapingRadial()
transfer.shapingVertical()
transfer.shapingTransverse()
transfer.assembleThrust()
# transfer.checkBoundaryConditions()
transfer.evaluate(evalThrust=True)
obj1 = transfer.deltaV
obj2 = transfer.maxThrust
return [obj1, obj2]
def boundaryConditionTestPos(rtol = 1e-3, atol = 1e-2):
# trajectory settings
depMjd = 10025
tof = 1050
N = 2
arrMjd = depMjd + tof
depBody = 'earth'
arrBody = 'mars'
ephems = 'jpl'
# departure and arrival states: rendezvous
scStateDep, __, __ = ephemeris(depBody, depMjd, mode=ephems)
scStateArr, __, __ = ephemeris(arrBody, arrMjd, mode=ephems)
transfer = hodographicShaping(scStateDep, scStateArr,
departureDate=depMjd, tof=tof, N=N,
departureBody = depBody,
arrivalBody = arrBody,
rShape = 'CPowPow2_scaled',
thetaShape = 'CPowPow2_scaled',
zShape = 'CosR5P3CosR5P3SinR5_scaled',
rShapeFree = 'PSin05PCos05_scaled',
thetaShapeFree = 'PSin05PCos05_scaled',
zShapeFree = 'P4CosR5P4SinR5_scaled',
rFreeC = [0, 0],
thetaFreeC = [0, 0],
zFreeC = [0, 0],
)
transfer.shapingRadial()
transfer.shapingVertical()
transfer.shapingTransverse()
testPoints = [transfer.r(transfer.tofSec),
transfer.t(transfer.tofSec),
# 0,
transfer.z(transfer.tofSec)]
# print(testPoints)
knownPoints = [219832470724.13513, 13.418874318624699, -77456667.88140798]
test = np.allclose(testPoints, knownPoints, rtol, atol)
if test == True:
print('OK\tBoundary conditions position test')
else:
print('ERROR\tBoundary conditions position test')
print('\tComputed: ', testPoints)
print('\tExpected: ', knownPoints)
def fullTest4(rtol = 1e-3, atol = 1e-2):
# trajectory settings
depMjd = 9453
tof = 844
N = 1
arrMjd = depMjd + tof
depBody = '3'
arrBody = '4'
ephems = 'spice'
# departure and arrival states: rendezvous
scStateDep, __, __ = ephemeris(depBody, depMjd, mode=ephems)
scStateArr, __, __ = ephemeris(arrBody, arrMjd, mode=ephems)
transfer = hodographicShaping(scStateDep, scStateArr,
departureDate=depMjd, tof=tof, N=N,
departureBody = depBody,
arrivalBody = arrBody,
rShape = 'CPowPow2_scaled',
thetaShape = 'CPowPow2_scaled',
zShape = 'CosR5P3CosR5P3SinR5_scaled',
rShapeFree = 'PSin05PCos05_scaled',
thetaShapeFree = 'PSin05PCos05_scaled',
zShapeFree = 'P4CosR5P4SinR5_scaled',
rFreeC = [137, 178],
thetaFreeC = [100, 1364],
zFreeC = [32, 283],
)
transfer.shapingRadial()
transfer.shapingVertical()
transfer.shapingTransverse()
transfer.assembleThrust()
transfer.checkBoundaryConditions()
transfer.evaluate(evalThrust='Grid', printTime=False, nEvalPoints = 1000)
testPoints = [transfer.psiTransfer, transfer.deltaV, transfer.maxThrust]
knownPoints = [5.213985160376169, 45508.713465061395, 0.0010283457257095393]
test = np.allclose(testPoints, knownPoints, rtol, atol)
if test == True:
print('OK\tFull test 4 (3-4, departureDate=9453, tof=844, N=1)')
else:
print('ERROR\tFull test 4 (3-4, departureDate=9453, tof=844, N=1)')
print('\tComputed: ', testPoints)
print('\tExpected: ', knownPoints)
def boundaryConditionTestVel(rtol = 1e-3, atol = 1e-2):
# trajectory settings
depMjd = 10025
tof = 1050
N = 2
arrMjd = depMjd + tof
depBody = 'earth'
arrBody = 'mars'
ephems = 'jpl'
# departure and arrival states: rendezvous
scStateDep, __, __ = ephemeris(depBody, depMjd, mode=ephems)
scStateArr, __, __ = ephemeris(arrBody, arrMjd, mode=ephems)
transfer = hodographicShaping(scStateDep, scStateArr,
departureDate=depMjd, tof=tof, N=N,
departureBody = depBody,
arrivalBody = arrBody,
rShape = 'CPowPow2_scaled',
thetaShape = 'CPowPow2_scaled',
zShape = 'CosR5P3CosR5P3SinR5_scaled',
rShapeFree = 'PSin05PCos05_scaled',
thetaShapeFree = 'PSin05PCos05_scaled',
zShapeFree = 'P4CosR5P4SinR5_scaled',
rFreeC = [0, 0],
thetaFreeC = [0, 0],
zFreeC = [0, 0],
)
transfer.shapingRadial()
transfer.shapingVertical()
transfer.shapingTransverse()
testPoints = [transfer.rDot(transfer.tofSec),
transfer.tDot(transfer.tofSec),
transfer.zDot(transfer.tofSec)]
# print(testPoints)
knownPoints = [2161.3061456572896, 24897.147647368587, 802.1571912246434]
test = np.allclose(testPoints, knownPoints, rtol, atol)
if test == True:
print('OK\tBoundary conditions velocity test')
else:
print('ERROR\tBoundary conditions velocity test')
print('\tComputed: ', testPoints)
print('\tExpected: ', knownPoints)
def fullTest1(rtol = 1e-3, atol = 1e-2):
depMjd = 8002
tof = 1500
N = 3
arrMjd = depMjd + tof
depBody = 'earth'
arrBody = 'mars'
scStateDep, __, __ = ephemeris(depBody, depMjd)
scStateArr, __, __ = ephemeris(arrBody, arrMjd)
transfer = hodographicShaping(scStateDep, scStateArr,
departureBody='earth', arrivalBody='mars',
departureDate=8002, tof=1500, N=3,
rShape = 'CPowPow2_scaled',
thetaShape = 'CPowPow2_scaled',
zShape = 'CosR5P3CosR5P3SinR5_scaled',
rShapeFree = 'PSin05PCos05_scaled',
thetaShapeFree = 'PSin05PCos05_scaled',
zShapeFree = 'P4CosR5P4SinR5_scaled',
rFreeC = [137, 178],
thetaFreeC = [100, 1364],
zFreeC = [32, 283],
)
transfer.shapingRadial()
transfer.shapingVertical()
transfer.shapingTransverse()
transfer.assembleThrust()
transfer.checkBoundaryConditions()
transfer.evaluate(evalThrust='Grid', printTime=False, nEvalPoints = 1000)
testPoints = [transfer.psiTransfer, transfer.deltaV, transfer.maxThrust]
# print(testPoints)
knownPoints = [3.858953628300317, 273559.833321966, 0.003146874363948356]
test = np.allclose(testPoints, knownPoints, rtol, atol)
if test == True:
print('OK\tFull test 1 (earth-mars, departureDate=8002, tof=1500, N=3)')
else:
print('ERROR\tFull test 1 (earth-mars, departureDate=8002,',
'tof=1500, N=3)')
print('\tComputed: ', testPoints)
print('\tExpected: ', knownPoints)
def main(folder = 'graveyard'):
"""
Evaluate patched low thrust trajectories
For explicit conditions resembling the Dawn mission:
Launch from Earth -> impulsive shot -> low-thrust to Mars -> swingby
-> low-thrust to Vesta -> rendezvous
All state vectors at this level are in cylindrical coordinates:
[radius, phi, z, v_r, vTheta, v_z]]
the only exception is the flyby computation, see below
"""
############################################################################
# Initialization
# output folder: Contents are overwritten each run!
outputFolder = os.path.join('output', folder)
checkFolder(outputFolder)
# reduce precision of printed numpy values
np.set_printoptions(precision=3)
# load spice kernels
ephems = 'spice'
loadSpiceKernels()
############################################################################
# Free parameters
# set up the problem: fixed parameters
ephems = 'spice'
# bodies
depBody = '3' # earth
arrBody = '4' # mars
arrBody2 = '2000004' # Vesta
arrBody4 = '2000001' # Ceres
# number of revolutions
N = 0
N2 = 1
N4 = 0
# orbit insertion (tangential inpulsive shot)
injectionDeltaV = [0, 2.42e3, 0]
# flyby parameters
swingbyPlanet = pk.planet.jpl_lp('mars')
arrVelMars = [-2.21e3, 2.17e4, -6.37e1]
flybyPlane = 2.71
flybyAltitude = 471e3
# dates
depMjd = 2782.2
tof = 407.6 # Earth - Mars
tof2 = 1099.1 # Mars- Vesta
tof3 = 559.2 # stay at Vesta
tof4 = 912.7 # transfer Vesta - Ceres
############################################################################
# Derived parameters
# Earth - Mars
arrMjd = depMjd + tof
planetStateDep, __, __ = ephemeris(depBody, depMjd, mode=ephems)
planetStateArr, plArCart, __ = ephemeris(arrBody, arrMjd, mode=ephems)
print('Mars arrival date', arrMjd)
print('Mars state cyl', planetStateArr)
print('Mars state cart', plArCart)
injectionDeltaVabs = np.linalg.norm(injectionDeltaV)
scStateDep = applyDeltaV(planetStateDep, injectionDeltaV)
scStateArr = np.array((planetStateArr[0:3], arrVelMars)).reshape(6,)
# swingby
scStateArrCart = stateCyl2cart(scStateArr) # convert state to Cartesian
# Mars - Vesta
depMjd2 = arrMjd
arrMjd2 = depMjd2 + tof2
depBody2 = arrBody
scStateArr2, __, __ = ephemeris(arrBody2, arrMjd2, mode=ephems)
# stay at Vesta
depMjd3 = arrMjd2
arrMjd3 = depMjd3 + tof3
body = arrBody2
# Vesta - Ceres
depMjd4 = arrMjd3
arrMjd4 = depMjd4 + tof4
depBody4 = body
scStateDep4, __, __ = ephemeris(depBody4, depMjd4, mode=ephems)
scStateArr4, __, __ = ephemeris(arrBody4, arrMjd4, mode=ephems)
############################################################################
# Computations
# low-thrust transfer to Mars
prob = pg.problem(myProblemShapingSingle(scStateDep, scStateArr,
depDate=depMjd, tof=tof, N=N,
depBody=depBody, target=arrBody))
pop, algo, initialGuess = optimizationSetup(prob)
print('Run Nelder-Mead to find good shape coefficients.')
start = time.process_time()
pop = algo.evolve(pop)
optiTime = time.process_time() - start
DeltaV1, c1 = getShapingResults(pop, algo, optiTime, initialGuess)
# flyby
scStateNewCart, swingbyDeltaV = flyby(scStateArrCart, 'mars',
flybyAltitude, flybyPlane, mode='jpl', mjd=arrMjd,
folder=outputFolder, makePlot=True, save=True, show=True)
scStateDep2 = stateCart2cyl(scStateNewCart) # convert back to Cylindrical
# low-thrust to Vesta
prob = pg.problem(myProblemShapingSingle(scStateDep2, scStateArr2,
depDate=depMjd2, tof=tof2, N=N2,
depBody=depBody2, target=arrBody2))
pop, algo, initialGuess = optimizationSetup(prob)
start = time.process_time()
print('Run Nelder-Mead to find good shape coefficients.')
pop = algo.evolve(pop)
optiTime = time.process_time() - start
DeltaV2, c2 = getShapingResults(pop, algo, optiTime, initialGuess)
# stay at Vesta
transfer3 = orbitFollowing(startDate=depMjd3, tof=tof3, body=body,
ephemSource=ephems)
# low-thrust to Ceres
prob = pg.problem(myProblemShapingSingle(scStateDep4, scStateArr4,
depDate=depMjd4, tof=tof4, N=N4,
depBody=depBody4, target=arrBody4))
pop, algo, initialGuess = optimizationSetup(prob)
start = time.process_time()
print('Run Nelder-Mead to find good shape coefficients.')
pop = algo.evolve(pop)
optiTime = time.process_time() - start
DeltaV4, c4 = getShapingResults(pop, algo, optiTime, initialGuess)
# compute the total DeltaV
totalDeltaV = np.squeeze(DeltaV1 + DeltaV2 + DeltaV4)
############################################################################
# Result outputs
# compute the individual transfers again for detailed results and plotting
details = False
print('Detailed results for each leg')
transfer = hodographicShaping(scStateDep, scStateArr,
departureDate=depMjd, tof=tof, N=N,
departureBody = depBody,
arrivalBody = arrBody,
rShape = 'CPowPow2_scaled',
thetaShape = 'CPowPow2_scaled',
zShape = 'CosR5P3CosR5P3SinR5_scaled',
rShapeFree = 'PSin05PCos05_scaled',
thetaShapeFree = 'PSin05PCos05_scaled',
zShapeFree = 'P4CosR5P4SinR5_scaled',
rFreeC = [c1[0], c1[1]],
thetaFreeC = [c1[2], c1[3]],
zFreeC = [c1[4], c1[5]],
)
transfer.shapingRadial()
transfer.shapingVertical()
transfer.shapingTransverse()
transfer.assembleThrust()
transfer.checkBoundaryConditions()
transfer.evaluate(evalThrust='Grid', printTime=False, nEvalPoints = 1000)
if details:
transfer.status(printBC=False)
transfer2 = hodographicShaping(scStateDep2, scStateArr2,
departureDate=depMjd2, tof=tof2, N=N2,
departureBody = depBody2,
arrivalBody = arrBody2,
rShape = 'CPowPow2_scaled',
thetaShape = 'CPowPow2_scaled',
zShape = 'CosR5P3CosR5P3SinR5_scaled',
rShapeFree = 'PSin05PCos05_scaled',
thetaShapeFree = 'PSin05PCos05_scaled',
zShapeFree = 'P4CosR5P4SinR5_scaled',
rFreeC = [c2[0], c2[1]],
thetaFreeC = [c2[2], c2[3]],
zFreeC = [c2[4], c2[5]],
)
transfer2.shapingRadial()
transfer2.shapingVertical()
transfer2.shapingTransverse()
transfer2.assembleThrust()
transfer2.checkBoundaryConditions()
transfer2.evaluate(evalThrust='Grid', printTime=False, nEvalPoints = 1000)
if details:
transfer2.status(printBC=True)
transfer4 = hodographicShaping(scStateDep4, scStateArr4,
departureDate=depMjd4, tof=tof4, N=N4,
departureBody = depBody4,
arrivalBody = arrBody4,
rShape = 'CPowPow2_scaled',
thetaShape = 'CPowPow2_scaled',
zShape = 'CosR5P3CosR5P3SinR5_scaled',
rShapeFree = 'PSin05PCos05_scaled',
thetaShapeFree = 'PSin05PCos05_scaled',
zShapeFree = 'P4CosR5P4SinR5_scaled',
rFreeC = [c4[0], c4[1]],
thetaFreeC = [c4[2], c4[3]],
zFreeC = [c4[4], c4[5]],
)
transfer4.shapingRadial()
transfer4.shapingVertical()
transfer4.shapingTransverse()
transfer4.assembleThrust()
transfer4.checkBoundaryConditions()
transfer4.evaluate(evalThrust='Grid', printTime=False, nEvalPoints = 1000)
if details:
transfer4.status(printBC=True)
# print overal results
print('###################################################################')
print(f'Results of patched trajectory computation')
print(f'Orbit injection impulse:\t{(injectionDeltaVabs)/1e3:>9.2f} km/s')
print(f'DeltaV Earth -> Mars:\t\t{np.squeeze(DeltaV1)/1e3:>9.2f} km/s')
print(f'Swingby DeltaV:\t\t\t{swingbyDeltaV/1e3:>9.2f} km/s')
print(f'DeltaV Mars -> Vesta:\t\t{np.squeeze(DeltaV2)/1e3:>9.2f} km/s')
print(f'DeltaV Vesta -> Ceres:\t\t{np.squeeze(DeltaV4)/1e3:>9.2f} km/s')
print(f'Total low-thrust DeltaV:\t{totalDeltaV/1e3:>9.2f} km/s')
print('###################################################################')
# generate combined plots
awesomePlotWonderland = patchedPlots(
[transfer, transfer2, transfer3, transfer4],
samples=1000,
folder=outputFolder,
save=True,
show=True,
addBody=[])
# awesomePlotWonderland.planetSystem(plotSOI=True, scaling=False)
awesomePlotWonderland.trajectory2D()
awesomePlotWonderland.trajectory3D(scaling=False)