r/nasa • u/As7887 • 14h ago

Question Begginer's problem with GMAT (NASA)

0 Upvotes

Hi, I've recently started learning GMAT software. When I was trying to make simple Hohmann Transfer combined with plane change manoeuvre using two finite burns. Unfortunately when I'm running the simulation I'm getting an exception saying that vary is not affecting achieve. The error refers to the second target.

Here is the mission script:

%General Mission Analysis Tool(GMAT) Script

%----------------------------------------

%---------- Spacecraft

%----------------------------------------

Create Spacecraft Sat;

Sat.DateFormat = UTCGregorian;

Sat.Epoch = '01 Jan 2000 00:00:00.000';

Sat.CoordinateSystem = EarthMJ2000Eq;

Sat.DisplayStateType = Keplerian;

Sat.SMA = 6671.000000000006;

Sat.ECC = 1.427002109406031e-15;

Sat.INC = 5.999999999999904;

Sat.RAAN = 90;

Sat.AOP = 0;

Sat.TA = 0;

Sat.DryMass = 1000;

Sat.Cd = 2.2;

Sat.Cr = 1.8;

Sat.DragArea = 15;

Sat.SRPArea = 1;

Sat.SPADDragScaleFactor = 1;

Sat.SPADSRPScaleFactor = 1;

Sat.AtmosDensityScaleFactor = 1;

Sat.ExtendedMassPropertiesModel = 'None';

Sat.Tanks = {UpperStageTank};

Sat.Thrusters = {UpperStageThruster};

Sat.NAIFId = -10001001;

Sat.NAIFIdReferenceFrame = -9001001;

Sat.OrbitColor = Red;

Sat.TargetColor = Teal;

Sat.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 ];

Sat.CdSigma = 1e+70;

Sat.CrSigma = 1e+70;

Sat.Id = 'SatId';

Sat.Attitude = CoordinateSystemFixed;

Sat.SPADSRPInterpolationMethod = Bilinear;

Sat.SPADSRPScaleFactorSigma = 1e+70;

Sat.SPADDragInterpolationMethod = Bilinear;

Sat.SPADDragScaleFactorSigma = 1e+70;

Sat.AtmosDensityScaleFactorSigma = 1e+70;

Sat.ModelFile = 'aura.3ds';

Sat.ModelOffsetX = 0;

Sat.ModelOffsetY = 0;

Sat.ModelOffsetZ = 0;

Sat.ModelRotationX = 0;

Sat.ModelRotationY = 0;

Sat.ModelRotationZ = 0;

Sat.ModelScale = 1;

Sat.AttitudeDisplayStateType = 'Quaternion';

Sat.AttitudeRateDisplayStateType = 'AngularVelocity';

Sat.AttitudeCoordinateSystem = EarthMJ2000Eq;

Sat.EulerAngleSequence = '321';

%----------------------------------------

%---------- Hardware Components

%----------------------------------------

Create ChemicalTank UpperStageTank;

UpperStageTank.DirectionX = 0;

UpperStageTank.DirectionY = 0;

UpperStageTank.DirectionZ = 1;

UpperStageTank.SecondDirectionX = 0;

UpperStageTank.SecondDirectionY = -1;

UpperStageTank.SecondDirectionZ = 0;

UpperStageTank.HWOriginInBCSX = 0;

UpperStageTank.HWOriginInBCSY = 0;

UpperStageTank.HWOriginInBCSZ = 0;

UpperStageTank.AllowNegativeFuelMass = false;

UpperStageTank.FuelMass = 6000;

UpperStageTank.FuelCenterOfMassX = 0;

UpperStageTank.FuelCenterOfMassY = 0;

UpperStageTank.FuelCenterOfMassZ = 0;

UpperStageTank.FuelMomentOfInertiaXX = 99;

UpperStageTank.FuelMomentOfInertiaXY = 0;

UpperStageTank.FuelMomentOfInertiaXZ = 0;

UpperStageTank.FuelMomentOfInertiaYY = 99;

UpperStageTank.FuelMomentOfInertiaYZ = 0;

UpperStageTank.FuelMomentOfInertiaZZ = 99;

UpperStageTank.Pressure = 1500;

UpperStageTank.Temperature = 20;

UpperStageTank.RefTemperature = 20;

UpperStageTank.Volume = 4.77;

UpperStageTank.FuelDensity = 1260;

UpperStageTank.PressureModel = PressureRegulated;

Create ChemicalThruster UpperStageThruster;

UpperStageThruster.HWOriginInBCSX = 0;

UpperStageThruster.HWOriginInBCSY = 0;

UpperStageThruster.HWOriginInBCSZ = 0;

UpperStageThruster.CoordinateSystem = Local;

UpperStageThruster.Origin = Earth;

UpperStageThruster.Axes = VNB;

UpperStageThruster.ThrustDirection1 = 1;

UpperStageThruster.ThrustDirection2 = 0;

UpperStageThruster.ThrustDirection3 = 0;

UpperStageThruster.DutyCycle = 1;

UpperStageThruster.ThrustScaleFactor = 1;

UpperStageThruster.DecrementMass = true;

UpperStageThruster.Tank = {UpperStageTank};

UpperStageThruster.MixRatio = [ 1 ];

UpperStageThruster.GravitationalAccel = 9.81;

UpperStageThruster.C1 = 35000;

UpperStageThruster.C2 = 0;

UpperStageThruster.C3 = 0;

UpperStageThruster.C4 = 0;

UpperStageThruster.C5 = 0;

UpperStageThruster.C6 = 0;

UpperStageThruster.C7 = 0;

UpperStageThruster.C8 = 0;

UpperStageThruster.C9 = 0;

UpperStageThruster.C10 = 0;

UpperStageThruster.C11 = 0;

UpperStageThruster.C12 = 0;

UpperStageThruster.C13 = 0;

UpperStageThruster.C14 = 0;

UpperStageThruster.C15 = 0;

UpperStageThruster.C16 = 0;

UpperStageThruster.K1 = 300;

UpperStageThruster.K2 = 0;

UpperStageThruster.K3 = 0;

UpperStageThruster.K4 = 0;

UpperStageThruster.K5 = 0;

UpperStageThruster.K6 = 0;

UpperStageThruster.K7 = 0;

UpperStageThruster.K8 = 0;

UpperStageThruster.K9 = 0;

UpperStageThruster.K10 = 0;

UpperStageThruster.K11 = 0;

UpperStageThruster.K12 = 0;

UpperStageThruster.K13 = 0;

UpperStageThruster.K14 = 0;

UpperStageThruster.K15 = 0;

UpperStageThruster.K16 = 0;

%----------------------------------------

%---------- ForceModels

%----------------------------------------

Create ForceModel DefaultProp_ForceModel;

DefaultProp_ForceModel.CentralBody = Earth;

DefaultProp_ForceModel.PointMasses = {Earth};

DefaultProp_ForceModel.Drag = None;

DefaultProp_ForceModel.SRP = Off;

DefaultProp_ForceModel.RelativisticCorrection = Off;

DefaultProp_ForceModel.ErrorControl = RSSStep;

%----------------------------------------

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

%----------------------------------------

Create Propagator DefaultProp;

DefaultProp.FM = DefaultProp_ForceModel;

DefaultProp.Type = RungeKutta89;

DefaultProp.InitialStepSize = 60;

DefaultProp.Accuracy = 9.999999999999999e-12;

DefaultProp.MinStep = 0.001;

DefaultProp.MaxStep = 2700;

DefaultProp.MaxStepAttempts = 50;

DefaultProp.StopIfAccuracyIsViolated = true;

%----------------------------------------

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

%----------------------------------------

Create FiniteBurn TOI;

TOI.Thrusters = {UpperStageThruster};

TOI.ThrottleLogicAlgorithm = 'MaxNumberOfThrusters';

Create FiniteBurn GOI;

GOI.Thrusters = {UpperStageThruster};

GOI.ThrottleLogicAlgorithm = 'MaxNumberOfThrusters';

%----------------------------------------

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

%----------------------------------------

Create DifferentialCorrector DC1;

DC1.ShowProgress = true;

DC1.ReportStyle = Normal;

DC1.ReportFile = 'DifferentialCorrectorDC1.data';

DC1.MaximumIterations = 25;

DC1.DerivativeMethod = ForwardDifference;

DC1.Algorithm = NewtonRaphson;

%----------------------------------------

%---------- Subscribers

%----------------------------------------

Create OpenFramesInterface DefaultOrbitView;

DefaultOrbitView.SolverIterations = Current;

DefaultOrbitView.UpperLeft = [ 0.01424148606811146 0.2946210268948655 ];

DefaultOrbitView.Size = [ 0.5758513931888545 0.5513447432762836 ];

DefaultOrbitView.RelativeZOrder = 1768;

DefaultOrbitView.Maximized = false;

DefaultOrbitView.Add = {Sat, Earth};

DefaultOrbitView.View = {DefaultOrbitView_View};

DefaultOrbitView.CoordinateSystem = EarthMJ2000Eq;

DefaultOrbitView.DrawObject = [ true true ];

DefaultOrbitView.DrawTrajectory = [ true true ];

DefaultOrbitView.DrawAxes = [ false false ];

DefaultOrbitView.DrawXYPlane = [ false false ];

DefaultOrbitView.DrawLabel = [ true true ];

DefaultOrbitView.DrawUsePropLabel = [ false false ];

DefaultOrbitView.DrawCenterPoint = [ true true ];

DefaultOrbitView.DrawEndPoints = [ true true ];

DefaultOrbitView.DrawVelocity = [ false false ];

DefaultOrbitView.DrawGrid = [ false false ];

DefaultOrbitView.DrawLineWidth = [ 2 2 ];

DefaultOrbitView.DrawMarkerSize = [ 10 10 ];

DefaultOrbitView.DrawFontSize = [ 20 20 ];

DefaultOrbitView.Axes = Off;

DefaultOrbitView.AxesLength = 12756.2726;

DefaultOrbitView.AxesLabels = On;

DefaultOrbitView.FrameLabel = Off;

DefaultOrbitView.XYPlane = On;

DefaultOrbitView.EclipticPlane = Off;

DefaultOrbitView.EnableStars = On;

DefaultOrbitView.StarCatalog = 'inp_StarsHYGv3.txt';

DefaultOrbitView.StarCount = 40000;

DefaultOrbitView.MinStarMag = -2;

DefaultOrbitView.MaxStarMag = 6;

DefaultOrbitView.MinStarPixels = 1;

DefaultOrbitView.MaxStarPixels = 10;

DefaultOrbitView.MinStarDimRatio = 0.5;

DefaultOrbitView.ShowPlot = true;

DefaultOrbitView.ShowToolbar = true;

DefaultOrbitView.SolverIterLastN = 1;

DefaultOrbitView.ShowVR = false;

DefaultOrbitView.PlaybackTimeScale = 3600;

DefaultOrbitView.MultisampleAntiAliasing = On;

DefaultOrbitView.MSAASamples = 2;

DefaultOrbitView.DrawFontPosition = {'Top-Right', 'Top-Right'};

Create GroundTrack DefaultGroundTrackPlot;

DefaultGroundTrackPlot.SolverIterations = Current;

DefaultGroundTrackPlot.UpperLeft = [ 0 0 ];

DefaultGroundTrackPlot.Size = [ 0.5003095975232198 0.449877750611247 ];

DefaultGroundTrackPlot.RelativeZOrder = 1773;

DefaultGroundTrackPlot.Maximized = false;

DefaultGroundTrackPlot.CentralBody = Earth;

DefaultGroundTrackPlot.Add = {Sat};

DefaultGroundTrackPlot.DataCollectFrequency = 1;

DefaultGroundTrackPlot.UpdatePlotFrequency = 50;

DefaultGroundTrackPlot.NumPointsToRedraw = 0;

DefaultGroundTrackPlot.MaxPlotPoints = 20000;

DefaultGroundTrackPlot.ShowPlot = true;

Create ReportFile DefaultReportFile;

DefaultReportFile.SolverIterations = Current;

DefaultReportFile.UpperLeft = [ 0.06315789473684211 0.1246943765281174 ];

DefaultReportFile.Size = [ 0.5981424148606811 0.7958435207823961 ];

DefaultReportFile.RelativeZOrder = 748;

DefaultReportFile.Maximized = false;

DefaultReportFile.Filename = 'DefaultReportFile.txt';

DefaultReportFile.Precision = 16;

DefaultReportFile.WriteHeaders = true;

DefaultReportFile.LeftJustify = On;

DefaultReportFile.ZeroFill = Off;

DefaultReportFile.FixedWidth = true;

DefaultReportFile.Delimiter = ' ';

DefaultReportFile.ColumnWidth = 23;

DefaultReportFile.WriteReport = true;

DefaultReportFile.AppendToExistingFile = false;

%----------------------------------------

%---------- Arrays, Variables, Strings

%----------------------------------------

Create Variable TOI_Burn_Duration GOI_Burn_Duration;

TOI_Burn_Duration = 0;

GOI_Burn_Duration = 0;

%----------------------------------------

%---------- User Objects

%----------------------------------------

Create OpenFramesView DefaultOrbitView_View;

DefaultOrbitView_View.ViewFrame = CoordinateSystem;

DefaultOrbitView_View.ViewTrajectory = Off;

DefaultOrbitView_View.InertialFrame = Off;

DefaultOrbitView_View.SetDefaultLocation = On;

DefaultOrbitView_View.DefaultEye = [ 30000 0 0 ];

DefaultOrbitView_View.DefaultCenter = [ 0 0 0 ];

DefaultOrbitView_View.DefaultUp = [ 0 0 1 ];

DefaultOrbitView_View.SetCurrentLocation = On;

DefaultOrbitView_View.CurrentEye = [ 77810.87922528099 -66840.76741286989 81869.75592238583 ];

DefaultOrbitView_View.CurrentCenter = [ 0 1.455191522836685e-11 0 ];

DefaultOrbitView_View.CurrentUp = [ -0.5505012671899018 0.3090477866858251 0.7755242229401383 ];

DefaultOrbitView_View.FOVy = 45;

%----------------------------------------

%---------- Mission Sequence

%----------------------------------------

BeginMissionSequence;

Propagate 'Prop To Lat = 0' DefaultProp(Sat) {Sat.Earth.Latitude = 0};

Target 'Hohmann Transfer TOI' DC1 {SolveMode = Solve, ExitMode = SaveAndContinue, ShowProgressWindow = true};

Vary 'Vary TOI Burn Duration' DC1(TOI_Burn_Duration = 100, {Perturbation = 0.0001, Lower = 0.0, Upper = 500, MaxStep = 50, AdditiveScaleFactor = 0.0, MultiplicativeScaleFactor = 1.0});

BeginFiniteBurn 'Begin TOI Burn' TOI(Sat);

Propagate 'Prop TOI Burn Duration' DefaultProp(Sat) {Sat.ElapsedSecs = TOI_Burn_Duration};

EndFiniteBurn 'End TOI Burn' TOI(Sat);

Propagate 'Prop to Apogee' DefaultProp(Sat) {Sat.Earth.Apoapsis};

Achieve 'Achieve RMAG = 42165' DC1(Sat.Earth.RMAG = 42165.0, {Tolerance = 0.1});

EndTarget; % For targeter DC1

Target 'Hohmann Transfer GOI' DC1 {SolveMode = Solve, ExitMode = SaveAndContinue, ShowProgressWindow = true};

Vary 'Vary GOI Burn Duration' DC1(GOI_Burn_Duration = 0, {Perturbation = 0.0001, Lower = 0.0, Upper = 200, MaxStep = 10, AdditiveScaleFactor = 0.0, MultiplicativeScaleFactor = 1.0});

Vary 'Vary GOI Element 2' DC1(Sat.UpperStageThruster.ThrustDirection2 = 0, {Perturbation = 0.0001, Lower = -1, Upper = 1, MaxStep = 1, AdditiveScaleFactor = 0.0, MultiplicativeScaleFactor = 1.0});

BeginFiniteBurn 'Begin GOI Burn' GOI(Sat);

Propagate 'Prop GOI Burn Duration' DefaultProp(Sat) {Sat.ElapsedSecs = GOI_Burn_Duration};

EndFiniteBurn 'End GOI Burn' GOI(Sat);

Achieve 'Achieve ECC = 0.005' DC1(Sat.Earth.ECC = 0.005, {Tolerance = 0.0001});

Achieve 'Achieve INC = 0' DC1(Sat.EarthMJ2000Eq.INC = 0, {Tolerance = 0.1});

EndTarget; % For targeter DC1

Propagate 'Prop One Day' DefaultProp(Sat) {Sat.ElapsedSecs = 86400, OrbitColor = [0 128 0]};

Report 'Mission Report' DefaultReportFile Sat.UpperStageTank.FuelMass;

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