ContinuousManeuverByEvents
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Révision de 28 juin 2018 à 08:32 par Admin (discussion | contributions)
public class ContinuousManeuverByEvents { public static void main(String[] args) throws PatriusException { // Patrius Dataset initialization (needed for example to get the UTC time) PatriusDataset.addResourcesFromPatriusDataset() ; // Recovery of the UTC time scale using a "factory" (not to duplicate such unique object) final TimeScale TUC = TimeScalesFactory.getUTC(); // Creating a mass model with a main part and with a tank final AssemblyBuilder builder = new AssemblyBuilder(); // Main part (dry mass) final double dryMass = 1000.; builder.addMainPart("MAIN"); builder.addProperty(new MassProperty(dryMass), "MAIN"); // Tank part (ergols mass) final double ergolsMass = 100.; final TankProperty tank = new TankProperty(ergolsMass); builder.addPart("TANK", "MAIN", Transform.IDENTITY); builder.addProperty(tank, "TANK"); // Engine part final double isp = 300.; final double thrust = 400.; final PropulsiveProperty prop = new PropulsiveProperty(thrust, isp); builder.addPart("PROP", "MAIN", Transform.IDENTITY); builder.addProperty(prop, "PROP"); final Assembly assembly = builder.returnAssembly(); final MassProvider mm = new MassModel(assembly); //SPECIFIC // Duration of the maneuver to get a 20 m/s boost final AbsoluteDate startDate = new AbsoluteDate("2010-01-01T12:00:00.000", TUC); final double G0 = 9.80665; final double duration = G0*isp*mm.getTotalMass()*(1. - FastMath.exp(-20/(G0*isp)))/thrust; // Start and end thrust events final EventDetector eventStart = new DateDetector(startDate); final EventDetector eventEnd = new DateDetector(startDate.shiftedBy(duration)); // Direction of the thrust in the X vehicle axis final Vector3D direction = new Vector3D(1., 0., 0.); // Creation of the continuous thrust maneuver final ContinuousThrustManeuver man = new ContinuousThrustManeuver(eventStart, eventEnd, prop, direction, mm, tank, LOFType.TNW); //SPECIFIC System.out.println("End of the thrust: "+man.getEndDate()); System.out.println("Duration of the thrust: "+duration+" s"); System.out.println("Duration of the thrust: "+man.getEndDate().durationFrom(startDate)+" s"); // The getFrame() method is returning "null" as a LOF frame is not define as a frame. // Nevertheless, an attitude law will not be mandatory when propagating the orbit. System.out.println("Maneuver frame: "+man.getFrame()); } }