gmat2020_hohmann.script

ex_hohmann.txt

%----------------------------------------
%---------- Spacecraft
%----------------------------------------
% Create spacecraft and define its orbit
Create Spacecraft ss_0;
GMAT ss_0.DateFormat = TAIModJulian;
GMAT ss_0.Epoch = '21545';
GMAT ss_0.CoordinateSystem = EarthICRF;
GMAT ss_0.DisplayStateType = Cartesian;
GMAT ss_0.X = 7200;
GMAT ss_0.Y = -1000;
GMAT ss_0.Z = 0;
GMAT ss_0.VX = 0;
GMAT ss_0.VY = 8;
GMAT ss_0.VZ =0;
GMAT ss_0.DryMass = 850;
GMAT ss_0.Cd = 2.2;
GMAT ss_0.Cr = 1.8;
GMAT ss_0.DragArea = 15;
GMAT ss_0.SRPArea = 1;
GMAT ss_0.SPADDragScaleFactor = 1;
GMAT ss_0.SPADSRPScaleFactor = 1;
GMAT ss_0.NAIFId = -10012001;
GMAT ss_0.NAIFIdReferenceFrame = -9012001;
GMAT ss_0.OrbitColor = Red;
GMAT ss_0.TargetColor = Teal;
GMAT ss_0.OrbitErrorCovariance = [ 1e+70 0 0 0 0 0 ; 0 1e+70 0 0 0 0 ; 0 0 1e+70 0 0 0 ; 0 0 0 1e+70 0 0 ; 0 0 0 0 1e+70 0 ; 0 0 0 0 0 1e+70 ];
GMAT ss_0.CdSigma = 1e+70;
GMAT ss_0.CrSigma = 1e+70;
GMAT ss_0.Id = 'SatId';
GMAT ss_0.Attitude = CoordinateSystemFixed;
GMAT ss_0.SPADSRPInterpolationMethod = Bilinear;
GMAT ss_0.SPADSRPScaleFactorSigma = 1e+70;
GMAT ss_0.SPADDragInterpolationMethod = Bilinear;
GMAT ss_0.SPADDragScaleFactorSigma = 1e+70;
GMAT ss_0.ModelFile = 'aura.3ds';
GMAT ss_0.ModelOffsetX = 0;
GMAT ss_0.ModelOffsetY = 0;
GMAT ss_0.ModelOffsetZ = 0;
GMAT ss_0.ModelRotationX = 0;
GMAT ss_0.ModelRotationY = 0;
GMAT ss_0.ModelRotationZ = 0;
GMAT ss_0.ModelScale = 1;
GMAT ss_0.AttitudeDisplayStateType = 'Quaternion';
GMAT ss_0.AttitudeRateDisplayStateType = 'AngularVelocity';
GMAT ss_0.AttitudeCoordinateSystem = EarthMJ2000Eq;
GMAT ss_0.EulerAngleSequence = '321';


%----------------------------------------
%---------- ForceModel
%----------------------------------------

%  Define Force Model with point mass only
Create ForceModel PointMass;
GMAT PointMass.CentralBody = Earth;
GMAT PointMass.PrimaryBodies = {Earth};
GMAT PointMass.Drag = None;
GMAT PointMass.SRP = Off;
GMAT PointMass.RelativisticCorrection = Off;
GMAT PointMass.ErrorControl = RSSStep;
GMAT PointMass.GravityField.Earth.Degree = 0;
GMAT PointMass.GravityField.Earth.Order = 0;
GMAT PointMass.GravityField.Earth.StmLimit = 100;
GMAT PointMass.GravityField.Earth.PotentialFile = '../data/gravity/earth/JGM2.cof';
GMAT PointMass.GravityField.Earth.TideModel = 'None';

%----------------------------------------
%---------- Propagators
%----------------------------------------

% Create propgator with point mass only
Create Propagator EarthPointMass;
GMAT EarthPointMass.FM = PointMass;
GMAT EarthPointMass.Type = PrinceDormand78;
GMAT EarthPointMass.InitialStepSize = 0.5;
GMAT EarthPointMass.Accuracy = 1e-12;
GMAT EarthPointMass.MinStep = 0;
GMAT EarthPointMass.MaxStep = 86400;
GMAT EarthPointMass.MaxStepAttempts = 500;
GMAT EarthPointMass.StopIfAccuracyIsViolated = false;

%----------------------------------------
%---------- Burns
%----------------------------------------

Create ImpulsiveBurn TOI;
GMAT TOI.CoordinateSystem = Local;
GMAT TOI.Origin = Earth;
GMAT TOI.Axes = VNB;
GMAT TOI.Element1 = 0;
GMAT TOI.Element2 = 0;
GMAT TOI.Element3 = 0;
GMAT TOI.DecrementMass = false;
GMAT TOI.Isp = 300;
GMAT TOI.GravitationalAccel = 9.81;

Create ImpulsiveBurn GOI;
GMAT GOI.CoordinateSystem = Local;
GMAT GOI.Origin = Earth;
GMAT GOI.Axes = VNB;
GMAT GOI.Element1 = 0;
GMAT GOI.Element2 = 0;
GMAT GOI.Element3 = 0;
GMAT GOI.DecrementMass = false;
GMAT GOI.Isp = 300;
GMAT GOI.GravitationalAccel = 9.81;

%----------------------------------------
%---------- Solvers
%----------------------------------------

Create DifferentialCorrector DC;
GMAT DC.ShowProgress = true;
GMAT DC.ReportStyle = Normal;
GMAT DC.ReportFile = 'DifferentialCorrectorDC.data';
GMAT DC.MaximumIterations = 25;
GMAT DC.DerivativeMethod = ForwardDifference;
GMAT DC.Algorithm = NewtonRaphson;

%----------------------------------------
%---------- Plots/Reports
%----------------------------------------

Create OrbitView GLPlot;
GMAT GLPlot.SolverIterations = Current;
GMAT GLPlot.UpperLeft = [ 0.2175843694493783 0.05272727272727273 ];
GMAT GLPlot.Size = [ 0.9911190053285968 0.9436363636363636 ];
GMAT GLPlot.RelativeZOrder = 143;
GMAT GLPlot.Maximized = true;
GMAT GLPlot.Add = {ss_0, Earth};
GMAT GLPlot.CoordinateSystem = EarthICRF;
GMAT GLPlot.DrawObject = [ true true ];
GMAT GLPlot.DataCollectFrequency = 1;
GMAT GLPlot.UpdatePlotFrequency = 50;
GMAT GLPlot.NumPointsToRedraw = 0;
GMAT GLPlot.ShowPlot = true;
GMAT GLPlot.MaxPlotPoints = 20000;
GMAT GLPlot.ShowLabels = true;
GMAT GLPlot.ViewPointReference = Earth;
GMAT GLPlot.ViewPointVector = [ -10000 -15000 3000 ];
GMAT GLPlot.ViewDirection = Earth;
GMAT GLPlot.ViewScaleFactor = 1.4;
GMAT GLPlot.ViewUpCoordinateSystem = EarthICRF;
GMAT GLPlot.ViewUpAxis = Z;
GMAT GLPlot.EclipticPlane = Off;
GMAT GLPlot.XYPlane = On;
GMAT GLPlot.WireFrame = Off;
GMAT GLPlot.Axes = On;
GMAT GLPlot.Grid = Off;
GMAT GLPlot.SunLine = Off;
GMAT GLPlot.UseInitialView = On;
GMAT GLPlot.StarCount = 7000;
GMAT GLPlot.EnableStars = On;
GMAT GLPlot.EnableConstellations = On;

Create ReportFile report;
GMAT report.SolverIterations = Current;
GMAT report.UpperLeft = [ 0.2175843694493783 0.05272727272727273 ];
GMAT report.Size = [ 0.9911190053285968 0.9436363636363636 ];
GMAT report.RelativeZOrder = 146;
GMAT report.Maximized = true;
GMAT report.Filename = 'ReportData.txt';
GMAT report.Precision = 16;
GMAT report.Add = {ss_0.UTCGregorian, ss_0.X, ss_0.Y, ss_0.Z, ss_0.VX, ss_0.VY, ss_0.VZ};
GMAT report.WriteHeaders = true;
GMAT report.LeftJustify = On;
GMAT report.ZeroFill = Off;
GMAT report.FixedWidth = true;
GMAT report.Delimiter = ' ';
GMAT report.ColumnWidth = 23;
GMAT report.WriteReport = true;


%----------------------------------------
%---------- Mission Sequence
%----------------------------------------
BeginMissionSequence;

Propagate 'Prop to Perigee' EarthPointMass(ss_0) {ss_0.Periapsis};

% Burn in the velocity direction to reach an alternate Apoapsis point
Target 'Raise and Circularize' DC {SolveMode = Solve, ExitMode = DiscardAndContinue, ShowProgressWindow = false};
   Vary 'Vary TOI.V' DC(TOI.Element1 = 0.5, {Perturbation = 0.0001, Lower = 0, Upper = 3.14159, MaxStep = 0.2, AdditiveScaleFactor = 0.0, MultiplicativeScaleFactor = 1.0});
   Maneuver 'Apply TOI' TOI(ss_0);
   Propagate 'Prop to Apogee' EarthPointMass(ss_0) {ss_0.Apoapsis};
   Achieve 'Achieve RMAG' DC(ss_0.Earth.RMAG = 35781.34857, {Tolerance = 0.01});
   Vary 'Vary GOI.V' DC(GOI.Element1 = 0.5, {Perturbation = 0.0001, Lower = 0, Upper = 3.14159, MaxStep = 0.2, AdditiveScaleFactor = 0.0, MultiplicativeScaleFactor = 1.0});
   Maneuver 'Apply GOI' GOI(ss_0);
   Achieve 'Achieve ECC' DC(ss_0.ECC = 0, {Tolerance = 0.01});
EndTarget;  % For targeter DC

Propagate 'Prop 1 hour' EarthPointMass(ss_0) {ss_0.ElapsedSecs = 3600};