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ReturnFromMoon.cs
681 lines (540 loc) · 28 KB
/
ReturnFromMoon.cs
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/*
* Copyright Lamont Granquist, Sebastien Gaggini and the MechJeb contributors
* SPDX-License-Identifier: LicenseRef-PD-hp OR Unlicense OR CC0-1.0 OR 0BSD OR MIT-0 OR MIT OR LGPL-2.1+
*/
using System;
using System.Diagnostics;
using MechJebLib.Functions;
using MechJebLib.Minimization;
using MechJebLib.Primitives;
using MechJebLib.TwoBody;
using static MechJebLib.Utils.Statics;
using static System.Math;
namespace MechJebLib.Maneuvers
{
public class ReturnFromMoon
{
private struct Args
{
public double MoonSOI;
public double PeR;
//public double Inc;
public V3 R0;
public V3 V0;
public V3 MoonR0;
public V3 MoonV0;
public Scale MoonToPlanetScale;
public Scale MoonScale;
public Scale PlanetScale;
}
private Args _args;
private void NLPFunction(double[] x, double[] fi, double[,] jac, object? o)
{
/*
* unpacking constants
*/
double moonSOI = _args.MoonSOI;
double peR = _args.PeR;
//double inc = _args.Inc;
V3 r0 = _args.R0;
V3 v0 = _args.V0;
V3 moonR0 = _args.MoonR0;
V3 moonV0 = _args.MoonV0;
Scale moonToPlanetScale = _args.MoonToPlanetScale;
/*
* unpacking optimizer variables
*/
var dv = new V3(x[0], x[1], x[2]);
double burnTime = x[3];
double moonDt1 = x[4];
double moonDt2 = x[5];
V3 rsoi = new V3(moonSOI, x[6], x[7]).sph2cart;
V3 vsoi = new V3(x[8], x[9], x[10]).sph2cart;
double moonDt = x[11];
double planetDt1 = x[12];
double planetDt2 = x[13];
var rf = new V3(x[14], x[15], x[16]);
var vf = new V3(x[17], x[18], x[19]);
// forward propagation in the moon SOI
(V3 rburn, V3 vburn) = Shepperd.Solve(1.0, burnTime, r0, v0);
V3 aburn = -rburn / (rburn.sqrMagnitude * rburn.magnitude);
(V3 r1Minus, V3 v1Minus, M3 v1MinusS00, M3 v1MinusS01, M3 v1MinusS10, M3 v1MinusS11) = Shepperd.Solve2(1.0, moonDt1, rburn, vburn + dv);
V3 a1Minus = -r1Minus / (r1Minus.sqrMagnitude * r1Minus.magnitude);
// reverse propagation in the moon SOI
(V3 r1Plus, V3 v1Plus, M3 v1PlusS00, M3 v1PlusS01, M3 v1PlusS10, M3 v1PlusS11) = Shepperd.Solve2(1.0, -moonDt2, rsoi, vsoi);
V3 a1Plus = -r1Plus / (r1Plus.sqrMagnitude * r1Plus.magnitude);
// propagation of the moon via the "ephemeris"
double t2 = moonDt / moonToPlanetScale.TimeScale;
(V3 moonR2, V3 moonV2) = Shepperd.Solve(1.0, t2, moonR0, moonV0);
V3 moonA2 = -moonR2 / (moonR2.sqrMagnitude * moonR2.magnitude);
V3 rsoiPlanet = rsoi / moonToPlanetScale.LengthScale + moonR2;
V3 vsoiPlanet = vsoi / moonToPlanetScale.VelocityScale + moonV2;
// forward propagation in the planet SOI
(V3 r2Minus, V3 v2Minus, M3 v2MinusS00, M3 v2MinusS01, M3 v2MinusS10, M3 v2MinusS11) =
Shepperd.Solve2(1.0, planetDt1, rsoiPlanet, vsoiPlanet);
V3 a2Minus = -r2Minus / (r2Minus.sqrMagnitude * r2Minus.magnitude);
// reverse propagation in the planet SOI
(V3 r2Plus, V3 v2Plus, M3 v2PlusS00, M3 v2PlusS01, M3 v2PlusS10, M3 v2PlusS11) = Shepperd.Solve2(1.0, -planetDt2, rf, vf);
V3 a2Plus = -r2Plus / (r2Plus.sqrMagnitude * r2Plus.magnitude);
Dual obj = new DualV3(dv, new V3(1, 0, 0)).sqrMagnitude;
fi[0] = obj.M;
jac[0, 0] = obj.D;
jac[0, 1] = new DualV3(dv, new V3(0, 1, 0)).sqrMagnitude.D;
jac[0, 2] = new DualV3(dv, new V3(0, 0, 1)).sqrMagnitude.D;
/*
* meet in the moon's SOI
*/
fi[1] = r1Minus.x - r1Plus.x;
fi[2] = r1Minus.y - r1Plus.y;
fi[3] = r1Minus.z - r1Plus.z;
fi[4] = v1Minus.x - v1Plus.x;
fi[5] = v1Minus.y - v1Plus.y;
fi[6] = v1Minus.z - v1Plus.z;
v1MinusS01.CopyTo(jac, 1, 0);
v1MinusS11.CopyTo(jac, 4, 0);
(v1MinusS00 * vburn + v1MinusS01 * aburn).CopyTo(jac, 1, 3);
(v1MinusS10 * vburn + v1MinusS11 * aburn).CopyTo(jac, 4, 3);
v1Minus.CopyTo(jac, 1, 4);
a1Minus.CopyTo(jac, 4, 4);
v1Plus.CopyTo(jac, 1, 5);
a1Plus.CopyTo(jac, 4, 5);
DualV3 rsoi6 = new DualV3(moonSOI, x[6], x[7], 0, 1, 0).sph2cart;
DualV3 rsoi7 = new DualV3(moonSOI, x[6], x[7], 0, 0, 1).sph2cart;
var d2 = new M3(rsoi6.D, rsoi7.D, V3.zero);
DualV3 vsoi8 = new DualV3(x[8], x[9], x[10], 1, 0, 0).sph2cart;
DualV3 vsoi9 = new DualV3(x[8], x[9], x[10], 0, 1, 0).sph2cart;
DualV3 vsoi10 = new DualV3(x[8], x[9], x[10], 0, 0, 1).sph2cart;
var d3 = new M3(vsoi8.D, vsoi9.D, vsoi10.D);
(-v1PlusS00 * d2).CopyTo(jac, 1, 6);
(-v1PlusS01 * d3).CopyTo(jac, 1, 8);
(-v1PlusS10 * d2).CopyTo(jac, 4, 6);
(-v1PlusS11 * d3).CopyTo(jac, 4, 8);
/*
* meet in the planet's SOI
*/
fi[7] = r2Minus.x - r2Plus.x;
fi[8] = r2Minus.y - r2Plus.y;
fi[9] = r2Minus.z - r2Plus.z;
fi[10] = v2Minus.x - v2Plus.x;
fi[11] = v2Minus.y - v2Plus.y;
fi[12] = v2Minus.z - v2Plus.z;
double l = moonToPlanetScale.LengthScale;
double v = moonToPlanetScale.VelocityScale;
double t = moonToPlanetScale.TimeScale;
DualV3 rsoiPlanet6 = new DualV3(moonSOI, x[6], x[7], 0, 1, 0).sph2cart / l + moonR2;
DualV3 rsoiPlanet7 = new DualV3(moonSOI, x[6], x[7], 0, 0, 1).sph2cart / l + moonR2;
var d0 = new M3(rsoiPlanet6.D, rsoiPlanet7.D, V3.zero);
DualV3 vsoiPlanet8 = new DualV3(x[8], x[9], x[10], 1, 0, 0).sph2cart / v + moonV2;
DualV3 vsoiPlanet9 = new DualV3(x[8], x[9], x[10], 0, 1, 0).sph2cart / v + moonV2;
DualV3 vsoiPlanet10 = new DualV3(x[8], x[9], x[10], 0, 0, 1).sph2cart / v + moonV2;
var d1 = new M3(vsoiPlanet8.D, vsoiPlanet9.D, vsoiPlanet10.D);
(v2MinusS00 * d0).CopyTo(jac, 7, 6);
(v2MinusS01 * d1).CopyTo(jac, 7, 8);
(v2MinusS10 * d0).CopyTo(jac, 10, 6);
(v2MinusS11 * d1).CopyTo(jac, 10, 8);
((v2MinusS00 * moonV2 + v2MinusS01 * moonA2) / t).CopyTo(jac, 7, 11);
((v2MinusS10 * moonV2 + v2MinusS11 * moonA2) / t).CopyTo(jac, 10, 11);
v2Minus.CopyTo(jac, 7, 12);
a2Minus.CopyTo(jac, 10, 12);
v2Plus.CopyTo(jac, 7, 13);
a2Plus.CopyTo(jac, 10, 13);
(-v2PlusS00).CopyTo(jac, 7, 14);
(-v2PlusS01).CopyTo(jac, 7, 17);
(-v2PlusS10).CopyTo(jac, 10, 14);
(-v2PlusS11).CopyTo(jac, 10, 17);
/*
* periapsis condition
*/
Dual p = DualV3.Dot(new DualV3(rf, new V3(1, 0, 0)), vf);
fi[13] = p.M;
jac[13, 14] = p.D;
jac[13, 15] = DualV3.Dot(new DualV3(rf, new V3(0, 1, 0)), vf).D;
jac[13, 16] = DualV3.Dot(new DualV3(rf, new V3(0, 0, 1)), vf).D;
jac[13, 17] = DualV3.Dot(rf, new DualV3(vf, new V3(1, 0, 0))).D;
jac[13, 18] = DualV3.Dot(rf, new DualV3(vf, new V3(0, 1, 0))).D;
jac[13, 19] = DualV3.Dot(rf, new DualV3(vf, new V3(0, 0, 1))).D;
/*
* periapsis constraint
*/
fi[14] = rf.sqrMagnitude - peR * peR;
jac[14, 14] = (new DualV3(rf, new V3(1, 0, 0)).sqrMagnitude - peR * peR).D;
jac[14, 15] = (new DualV3(rf, new V3(0, 1, 0)).sqrMagnitude - peR * peR).D;
jac[14, 16] = (new DualV3(rf, new V3(0, 0, 1)).sqrMagnitude - peR * peR).D;
/*
* time constraints
*/
fi[15] = moonDt1 + moonDt2 + burnTime - moonDt;
jac[15, 3] = 1.0;
jac[15, 4] = 1.0;
jac[15, 5] = 1.0;
jac[15, 11] = -1.0;
/*
* midpoint time constraints
*/
fi[16] = moonDt1 - moonDt2;
jac[16, 4] = 1.0;
jac[16, 5] = -1.0;
fi[17] = planetDt1 - planetDt2;
jac[17, 12] = 1.0;
jac[17, 13] = -1.0;
}
private (V3 dv, double dt, V3 rf, V3 vf, double tt2) Guess(double inc, bool type2, bool full = false)
{
double moonSOI = _args.MoonSOI;
double peR = _args.PeR;
V3 r0 = _args.R0;
V3 v0 = _args.V0;
V3 moonR0 = _args.MoonR0;
V3 moonV0 = _args.MoonV0;
Scale planetScale = _args.PlanetScale;
Scale moonScale = _args.MoonScale;
Scale moonToPlanetScale = _args.MoonToPlanetScale;
V3 moonRsoi = moonR0;
V3 moonVsoi = moonV0;
V3 dv = V3.maxvalue;
V3 vf = V3.zero, rf = V3.zero;
double dt = 0;
double tt2 = 0;
for (int i = 0; i < 2; i++)
{
// kick the moon's orbit to the new peR and inc to build the return ellipse
V3 dv1 = ChangeOrbitalElement.ChangeApsis(1.0, moonRsoi, moonVsoi, peR);
dv1 += Simple.DeltaVToChangeInclination(moonRsoi, moonVsoi + dv1, inc);
// get the return ellipse keplerian elements
(double sma, double ecc, double _, double lan, double argp, double _, double l) =
Astro.KeplerianFromStateVectors(1.0, moonRsoi, moonVsoi + dv1);
// find approximate tanom of the moon's SOI on the return ellipse
double moonSOI2 = moonSOI / moonToPlanetScale.LengthScale;
double rsoi = 2 * sma - moonSOI2;
double nuSOI = SafeAcos((sma * (1 - ecc * ecc) / rsoi - 1) / ecc);
// type2 return a transfer that starts with tanom < 180
if (!type2)
nuSOI = TAU - nuSOI;
// get the SOI ejection point on the return ellipse
(V3 rsoiPlanet, V3 vsoiPlanet) = Astro.StateVectorsFromKeplerian(1.0, 1.2 * l, ecc, inc, lan, argp, nuSOI);
tt2 = Astro.TimeToNextTrueAnomaly(1.0, rsoiPlanet, vsoiPlanet, 0);
if (full)
{
// get the final periapsis position on the return ellipse for actual initial guess
(rf, vf) = Astro.StateVectorsFromKeplerian(1.0, l, ecc, inc, lan, argp, 0);
(double sma3, double ecc3, double inc3, double lan3, double argp3, double tanom3, double l3) =
Astro.KeplerianFromStateVectors(1.0, rsoiPlanet, vsoiPlanet);
Print(
$"Guessed return ellipse:\nsma:{sma3 * planetScale.LengthScale} ecc:{ecc3} inc:{Rad2Deg(inc3)} lan:{Rad2Deg(lan3)} argp:{Rad2Deg(argp3)} tanom:{Rad2Deg(tanom3)}");
Print($"vinf fed to hyperbolic guesser: {(vsoiPlanet - moonVsoi) * moonToPlanetScale.VelocityScale * moonScale.VelocityScale}");
}
V3 vneg, vpos, rburn;
(vneg, vpos, rburn, dt) =
Astro.SingleImpulseHyperbolicBurn(1.0, r0, v0, (vsoiPlanet - moonVsoi) * moonToPlanetScale.VelocityScale);
dv = vpos - vneg;
double tt = Astro.TimeToNextRadius(1.0, rburn, vpos, moonSOI);
(moonRsoi, moonVsoi) = Shepperd.Solve(1.0, (dt + tt) / moonToPlanetScale.TimeScale, moonR0, moonV0);
}
return (dv, dt, rf, vf, tt2);
}
private (double inc, bool type2) GuessOptimizer()
{
double f, fx;
double imin = 0, imincost = double.MaxValue;
bool type2 = false;
(f, fx) = BrentMin.Solve((x, o) => Guess(x, false).Item1.magnitude, -PI, 0, rtol: 1e-2);
if (fx < imincost)
{
imin = f;
imincost = fx;
type2 = false;
}
(f, fx) = BrentMin.Solve((x, o) => Guess(x, false).Item1.magnitude, 0, PI, rtol: 1e-2);
if (fx < imincost)
{
imin = f;
imincost = fx;
type2 = false;
}
(f, fx) = BrentMin.Solve((x, o) => Guess(x, true).Item1.magnitude, -PI, 0, rtol: 1e-2);
if (fx < imincost)
{
imin = f;
imincost = fx;
type2 = true;
}
(f, fx) = BrentMin.Solve((x, o) => Guess(x, true).Item1.magnitude, 0, PI, rtol: 1e-2);
if (fx < imincost)
{
imin = f;
imincost = fx;
type2 = true;
}
Scale moonScale = _args.MoonScale;
Print($"{Rad2Deg(imin)} {imincost * moonScale.VelocityScale} {type2}");
return (imin, type2);
}
private double[] GenerateInitialGuess()
{
var sw = new Stopwatch();
sw.Start();
double[] x = new double[NVARIABLES];
double moonSOI = _args.MoonSOI;
double peR = _args.PeR;
V3 r0 = _args.R0;
V3 v0 = _args.V0;
V3 moonR0 = _args.MoonR0;
V3 moonV0 = _args.MoonV0;
Scale moonScale = _args.MoonScale;
Scale moonToPlanetScale = _args.MoonToPlanetScale;
double dt, tt2 = 0;
V3 dv, rf = V3.zero, vf = V3.zero;
if (Astro.EccFromStateVectors(1.0, r0, v0) < 1 && Astro.ApoapsisFromStateVectors(1.0, r0, v0) < moonSOI)
{
(double imin, bool type2) = GuessOptimizer();
(dv, dt, rf, vf, tt2) = Guess(imin, type2, true);
}
else
{
// if we're already on an escape trajectory, try an immediate burn and hope we're reasonably close
(dv, dt, rf, vf, tt2) = InitiallyHyperbolicGuess();
}
(V3 rburn, V3 vburn) = Shepperd.Solve(1.0, dt, r0, v0);
double tt1 = Astro.TimeToNextRadius(1.0, rburn, vburn + dv, moonSOI);
(V3 rsoi, V3 vsoi) = Shepperd.Solve(1.0, tt1, rburn, vburn + dv);
Print($"vsoi from analytic ejection guess: {vsoi * moonScale.VelocityScale}");
(V3 rsoiPlanet, V3 vsoiPlanet) = Shepperd.Solve(1.0, -tt2, rf, vf);
(V3 moonR1, V3 moonV1) = Shepperd.Solve(1.0, dt + tt1, moonR0, moonV0);
V3 vsoi2 = (vsoiPlanet - moonV1) * moonToPlanetScale.VelocityScale;
Print($"vsoi working backwards from rf, vf: {vsoi2 * moonScale.VelocityScale}");
V3 r2Sph = rsoi.cart2sph;
//V3 v2Sph = vsoi2.cart2sph;
// taking the average of the mismatch in vsoi and spreading the infeasibility over both SOIs seems to actually
// produce better convergence properties.
V3 v2Sph = ((vsoi2 + vsoi) / 2).cart2sph;
Print($"vsoi in initial guess: {v2Sph.sph2cart * moonScale.VelocityScale}");
x[0] = dv.x; // maneuver x (moonscale)
x[1] = dv.y; // maneuver y (moonscale)
x[2] = dv.z; // maneuver z (moonscale)
x[3] = dt; // maneuver dt (moonscale)
x[4] = tt1 * 0.5; // 1/2 coast time through moon SOI (moonscale)
x[5] = tt1 * 0.5; // 1/2 coast time through moon SOI (moonscale)
x[6] = r2Sph[1]; // theta of SOI position (angle)
x[7] = r2Sph[2]; // phi of SOI position (angle)
x[8] = v2Sph[0]; // magnitude of SOI velocity (moonscale)
x[9] = v2Sph[1]; // theta of SOI velocity (angle)
x[10] = v2Sph[2]; // phi of SOI velocity (angle)
x[11] = tt1 + dt; // total time in the moon SOI (moonscale)
x[12] = tt2 * 0.5; // 1/2 coast time through planet SOI (planetscale)
x[13] = tt2 * 0.5; // 1/2 coast time thorugh planet SOI (planetscale)
x[14] = rf.x; // final rx (planetscale)
x[15] = rf.y; // final ry (planetscale)
x[16] = rf.z; // final rz (planetscale)
x[17] = vf.x; // final vx (planetscale)
x[18] = vf.y; // final vy (planetscale)
x[19] = vf.z; // final vz (planetscale)
sw.Stop();
Print($"initial guess generation took {sw.ElapsedMilliseconds}ms");
return x;
}
private (V3 dv, double dt, V3 rf, V3 vf, double tt2) InitiallyHyperbolicGuess()
{
double moonSOI = _args.MoonSOI;
double peR = _args.PeR;
V3 r0 = _args.R0;
V3 v0 = _args.V0;
V3 moonR0 = _args.MoonR0;
V3 moonV0 = _args.MoonV0;
Scale moonToPlanetScale = _args.MoonToPlanetScale;
double tt1 = Astro.TimeToNextRadius(1.0, r0, v0, moonSOI);
(V3 r2, V3 v2) = Shepperd.Solve(1.0, tt1, r0, v0);
(V3 moonR2, V3 moonV2) = Shepperd.Solve(1.0, tt1 / moonToPlanetScale.TimeScale, moonR0, moonV0);
V3 r3 = r2 / moonToPlanetScale.LengthScale + moonR2;
V3 v3 = v2 / moonToPlanetScale.VelocityScale + moonV2;
(V3 rf, V3 vf) = Astro.StateVectorsAtTrueAnomaly(1.0, r3, v3, 0);
double tt2 = Astro.TimeToNextTrueAnomaly(1.0, r3, v3, 0);
rf = rf.normalized * peR;
vf = V3.Cross(V3.Cross(rf, vf), rf).normalized * vf.magnitude;
return (V3.zero, 0, rf, vf, tt2);
}
private const double DIFFSTEP = 1e-9;
private const double EPSX = 1e-5;
private const double STPMAX = 1e-4;
private const int MAXITS = 10000;
private const int NVARIABLES = 20;
private const int NEQUALITYCONSTRAINTS = 17;
private const int NINEQUALITYCONSTRAINTS = 0;
private (V3 V, double dt, V3 vinf) ManeuverScaled(double dtmin = double.NegativeInfinity, double dtmax = double.PositiveInfinity,
bool optguard = false)
{
double[] x = GenerateInitialGuess();
double[] bndl = new double[NVARIABLES];
double[] bndu = new double[NVARIABLES];
for (int i = 0; i < NVARIABLES; i++)
{
bndl[i] = double.NegativeInfinity;
bndu[i] = double.PositiveInfinity;
}
bndl[3] = dtmin;
bndu[3] = dtmax;
//alglib.minnlccreatef(NVARIABLES, x, DIFFSTEP, out alglib.minnlcstate state);
alglib.minnlccreate(NVARIABLES, x, out alglib.minnlcstate state);
alglib.minnlcsetbc(state, bndl, bndu);
alglib.minnlcsetstpmax(state, STPMAX);
//double rho = 1000.0;
//int outerits = 5;
//alglib.minnlcsetalgoaul(state, rho, outerits);
//alglib.minnlcsetalgoslp(state);
alglib.minnlcsetalgosqp(state);
alglib.minnlcsetcond(state, EPSX, MAXITS);
alglib.minnlcsetnlc(state, NEQUALITYCONSTRAINTS, NINEQUALITYCONSTRAINTS);
if (optguard)
{
alglib.minnlcoptguardsmoothness(state);
alglib.minnlcoptguardgradient(state, DIFFSTEP);
}
double[] fi = new double[NEQUALITYCONSTRAINTS + NINEQUALITYCONSTRAINTS + 1];
double[,] jac = new double[NEQUALITYCONSTRAINTS + NINEQUALITYCONSTRAINTS + 1, NVARIABLES];
NLPFunction(x, fi, jac, null);
var sw = new Stopwatch();
sw.Start();
alglib.minnlcoptimize(state, NLPFunction, null, null);
sw.Stop();
alglib.minnlcresults(state, out double[] x2, out alglib.minnlcreport rep);
Print($"optimization took {sw.ElapsedMilliseconds}ms: {rep.iterationscount} iter, {rep.nfev} fev");
NLPFunction(x2, fi, jac, null);
for (int i = 0; i < x2.Length; i++)
Print($"x[{i}]: {x2[i]} - {x[i]} = {x2[i] - x[i]} ({100 * (x2[i] - x[i]) / x2[i]}%)");
if (optguard)
{
alglib.minnlcoptguardresults(state, out alglib.optguardreport ogrep);
if (ogrep.badgradsuspected)
throw new Exception(
$"badgradsuspected: {ogrep.badgradfidx},{ogrep.badgradvidx}\nuser:\n{DoubleMatrixString(ogrep.badgraduser)}\nnumerical:\n{DoubleMatrixString(ogrep.badgradnum)}\nsparsity check:\n{DoubleMatrixSparsityCheck(ogrep.badgraduser, ogrep.badgradnum, 1e-2)}");
if (ogrep.nonc0suspected || ogrep.nonc1suspected)
throw new Exception("alglib optguard caught an error, i should report better on errors now");
}
if (rep.terminationtype < 0)
throw new Exception(
$"ReturnFromMoon.Maneuver(): SQP solver terminated abnormally: {rep.terminationtype}"
);
if (rep.nlcerr > 1e-4)
throw new Exception(
$"ReturnFromMoon.Maneuver() no feasible solution found, constraint violation: {rep.nlcerr}");
return (new V3(x2[0], x2[1], x2[2]), x2[3], new V3(x2[8], x2[9], x2[10]).sph2cart);
}
private (V3 V, double dt) Maneuver(double centralMu, double moonMu, V3 moonR0, V3 moonV0, double moonSOI,
V3 r0, V3 v0, double peR, double inc, double dtmin = double.NegativeInfinity, double dtmax = double.PositiveInfinity,
bool optguard = false)
{
Print(
$"ReturnFromMoon.Maneuver({centralMu}, {moonMu}, new V3({moonR0}), new V3({moonV0}), {moonSOI}, new V3({r0}), new V3({v0}), {peR}, {inc})");
var moonScale = Scale.Create(moonMu, Sqrt(r0.magnitude * moonSOI));
var planetScale = Scale.Create(centralMu, Sqrt(moonR0.magnitude * peR));
Scale moonToPlanetScale = moonScale.ConvertTo(planetScale);
_args = new Args
{
MoonSOI = moonSOI / moonScale.LengthScale,
PeR = peR / planetScale.LengthScale,
//Inc = inc,
R0 = r0 / moonScale.LengthScale,
V0 = v0 / moonScale.VelocityScale,
MoonR0 = moonR0 / planetScale.LengthScale,
MoonV0 = moonV0 / planetScale.VelocityScale,
MoonToPlanetScale = moonToPlanetScale,
MoonScale = moonScale,
PlanetScale = planetScale
};
LogStuff1(moonScale);
/*
for(double i = -PI; i <= PI; i += PI/36)
{
(V3 dv2, _, _, _, _) = Guess(i, false);
Print($"{Rad2Deg(i)} false {dv2.magnitude * moonScale.VelocityScale}");
}
for(double i = -PI; i <= PI; i += PI/36)
{
(V3 dv2, _, _, _, _) = Guess(i, true);
Print($"{Rad2Deg(i)} true {dv2.magnitude * moonScale.VelocityScale}");
}
*/
var sw = new Stopwatch();
sw.Start();
(V3 dv, double dt, V3 vinf) = ManeuverScaled(dtmin / moonScale.TimeScale, dtmax / moonScale.TimeScale, optguard);
sw.Stop();
Print($"total calculation took {sw.ElapsedMilliseconds}ms");
LogStuff2(dv, dt, vinf);
return (dv * moonScale.VelocityScale, dt * moonScale.TimeScale);
}
private void LogStuff1(Scale moonScale)
{
V3 r0 = _args.R0;
V3 v0 = _args.V0;
V3 moonR0 = _args.MoonR0;
V3 moonV0 = _args.MoonV0;
Scale planetScale = _args.PlanetScale;
(double sma, double ecc, double inc, double lan, double argp, double tanom, _) =
Astro.KeplerianFromStateVectors(1.0, moonR0, moonV0);
Print(
$"Secondary celestial orbit:\nsma:{sma * planetScale.LengthScale} ecc:{ecc} inc:{Rad2Deg(inc)} lan:{Rad2Deg(lan)} argp:{Rad2Deg(argp)} tanom:{Rad2Deg(tanom)}");
(sma, ecc, inc, lan, argp, tanom, _) =
Astro.KeplerianFromStateVectors(1.0, r0, v0);
Print(
$"Parking orbit around Secondary:\nsma:{sma * moonScale.LengthScale} ecc:{ecc} inc:{Rad2Deg(inc)} lan:{Rad2Deg(lan)} argp:{Rad2Deg(argp)} tanom:{Rad2Deg(tanom)}");
}
private void LogStuff2(V3 dv, double dt, V3 vinf)
{
double moonSOI = _args.MoonSOI;
V3 r0 = _args.R0;
V3 v0 = _args.V0;
V3 moonR0 = _args.MoonR0;
V3 moonV0 = _args.MoonV0;
Scale moonToPlanetScale = _args.MoonToPlanetScale;
Scale planetScale = _args.PlanetScale;
Scale moonScale = _args.MoonScale;
(V3 r1, V3 v1) = Shepperd.Solve(1.0, dt, r0, v0);
double tt1 = Astro.TimeToNextRadius(1.0, r1, v1 + dv, moonSOI);
(V3 r2, V3 v2) = Shepperd.Solve(1.0, tt1, r1, v1 + dv);
(V3 moonR2, V3 moonV2) = Shepperd.Solve(1.0, (dt + tt1) / moonToPlanetScale.TimeScale, moonR0, moonV0);
V3 r3 = r2 / moonToPlanetScale.LengthScale + moonR2;
V3 v3 = v2 / moonToPlanetScale.VelocityScale + moonV2;
(double sma, double ecc, double inc, double lan, double argp, double tanom, _) =
Astro.KeplerianFromStateVectors(1.0, r2, v2);
Print(
$"Ejection orbit around Secondary:\nsma:{sma * moonScale.LengthScale} ecc:{ecc} inc:{Rad2Deg(inc)} lan:{Rad2Deg(lan)} argp:{Rad2Deg(argp)} tanom:{Rad2Deg(tanom)}");
(sma, ecc, inc, lan, argp, tanom, _) =
Astro.KeplerianFromStateVectors(1.0, r3, v3);
Print(
$"Return orbit around Primary:\nsma:{sma * planetScale.LengthScale} ecc:{ecc} inc:{Rad2Deg(inc)} lan:{Rad2Deg(lan)} argp:{Rad2Deg(argp)} tanom:{Rad2Deg(tanom)}");
double peR = Astro.PeriapsisFromStateVectors(1.0, r3, v3);
Print(
$"deltaV: {dv * moonScale.VelocityScale}/{dv.magnitude * moonScale.VelocityScale} dt: {dt * moonScale.TimeScale} vinf: {vinf * moonScale.VelocityScale} PeR: {peR * planetScale.LengthScale} (solved)");
if (Astro.EccFromStateVectors(1.0, r0, v0) < 1 && Astro.ApoapsisFromStateVectors(1.0, r0, v0) < moonSOI)
{
(V3 vneg, V3 vpos, V3 _, double dt2) = Astro.SingleImpulseHyperbolicBurn(1.0, r0, v0, vinf);
V3 dv2 = vpos - vneg;
Print(
$"deltaV: {dv2 * moonScale.VelocityScale}/{dv2.magnitude * moonScale.VelocityScale} dt: {dt2 * moonScale.TimeScale} (analytic validation)");
}
}
public (V3 dv, double dt, double newPeR) NextManeuver(double centralMu, double moonMu, V3 moonR0, V3 moonV0,
double moonSOI, V3 r0, V3 v0, double peR, double inc, double dtmin = double.NegativeInfinity, double dtmax = double.PositiveInfinity,
bool optguard = false)
{
double dt;
V3 dv;
int i = 0;
(double _, double ecc) = Astro.SmaEccFromStateVectors(moonMu, r0, v0);
while (true)
{
(dv, dt) = Maneuver(centralMu, moonMu, moonR0, moonV0, moonSOI, r0, v0, peR, inc, dtmin, dtmax, optguard);
if (dt > 0 || ecc >= 1)
break;
if (i++ >= 5)
throw new Exception("Maximum iterations exceeded with no valid future solution");
(r0, v0) = Shepperd.Solve(moonMu, Astro.PeriodFromStateVectors(moonMu, r0, v0), r0, v0);
}
(V3 r1, V3 v1) = Shepperd.Solve(moonMu, dt, r0, v0);
double tt1 = Astro.TimeToNextRadius(moonMu, r1, v1 + dv, moonSOI);
(V3 r2, V3 v2) = Shepperd.Solve(moonMu, tt1, r1, v1 + dv);
(V3 moonR2, V3 moonV2) = Shepperd.Solve(centralMu, dt + tt1, moonR0, moonV0);
double newPeR = Astro.PeriapsisFromStateVectors(centralMu, moonR2 + r2, moonV2 + v2);
return (dv, dt, newPeR);
}
}
}