Exemple #1
0
        /// <summary>
        /// Standard constructor.
        /// </summary>
        /// <param name="tle">Two-line element orbital parameters.</param>
        public Orbit(Tle tle)
        {
            Tle   = tle;
            Epoch = Tle.EpochJulian;

            m_Inclination   = GetRad(Tle.Field.Inclination);
            m_Eccentricity  = Tle.GetField(Tle.Field.Eccentricity);
            m_RAAN          = GetRad(Tle.Field.Raan);
            m_ArgPerigee    = GetRad(Tle.Field.ArgPerigee);
            m_BStar         = Tle.GetField(Tle.Field.BStarDrag);
            m_Drag          = Tle.GetField(Tle.Field.MeanMotionDt);
            m_MeanAnomaly   = GetRad(Tle.Field.MeanAnomaly);
            m_TleMeanMotion = Tle.GetField(Tle.Field.MeanMotion);

            // Recover the original mean motion and semimajor axis from the
            // input elements.
            double mm    = TleMeanMotion;
            double rpmin = mm * Globals.TwoPi / Globals.MinPerDay; // rads per minute

            double a1   = Math.Pow(Globals.Xke / rpmin, 2.0 / 3.0);
            double e    = Eccentricity;
            double i    = Inclination;
            double temp = (1.5 * Globals.Ck2 * (3.0 * Globals.Sqr(Math.Cos(i)) - 1.0) /
                           Math.Pow(1.0 - e * e, 1.5));
            double delta1 = temp / (a1 * a1);
            double a0     = a1 *
                            (1.0 - delta1 *
                             ((1.0 / 3.0) + delta1 *
                              (1.0 + 134.0 / 81.0 * delta1)));

            double delta0 = temp / (a0 * a0);

            m_rmMeanMotionRec    = rpmin / (1.0 + delta0);
            m_aeAxisSemiMajorRec = a0 / (1.0 - delta0);
            m_aeAxisSemiMinorRec = m_aeAxisSemiMajorRec * Math.Sqrt(1.0 - (e * e));
            m_kmPerigeeRec       = Globals.Xkmper * (m_aeAxisSemiMajorRec * (1.0 - e) - Globals.Ae);
            m_kmApogeeRec        = Globals.Xkmper * (m_aeAxisSemiMajorRec * (1.0 + e) - Globals.Ae);

            if (Period.TotalMinutes >= 225.0)
            {
                // SDP4 - period >= 225 minutes.
                NoradModel = new NoradSDP4(this);
            }
            else
            {
                // SGP4 - period < 225 minutes
                NoradModel = new NoradSGP4(this);
            }
        }
Exemple #2
0
      /// <summary>
      /// Standard constructor.
      /// </summary>
      /// <param name="tle">Two-line element orbital parameters.</param>
      public Orbit(Tle tle)
      {
         Tle     = tle;
         Epoch = Tle.EpochJulian;

         m_Inclination   = GetRad(Tle.Field.Inclination);
         m_Eccentricity  = Tle.GetField(Tle.Field.Eccentricity);
         m_RAAN          = GetRad(Tle.Field.Raan);              
         m_ArgPerigee    = GetRad(Tle.Field.ArgPerigee);        
         m_BStar         = Tle.GetField(Tle.Field.BStarDrag);   
         m_Drag          = Tle.GetField(Tle.Field.MeanMotionDt);
         m_MeanAnomaly   = GetRad(Tle.Field.MeanAnomaly);
         m_TleMeanMotion = Tle.GetField(Tle.Field.MeanMotion);  

         // Recover the original mean motion and semimajor axis from the
         // input elements.
         double mm     = TleMeanMotion;
         double rpmin  = mm * Globals.TwoPi / Globals.MinPerDay;   // rads per minute

         double a1     = Math.Pow(Globals.Xke / rpmin, 2.0 / 3.0);
         double e      = Eccentricity;
         double i      = Inclination;
         double temp   = (1.5 * Globals.Ck2 * (3.0 * Globals.Sqr(Math.Cos(i)) - 1.0) / 
                         Math.Pow(1.0 - e * e, 1.5));   
         double delta1 = temp / (a1 * a1);
         double a0     = a1 * 
                        (1.0 - delta1 * 
                        ((1.0 / 3.0) + delta1 * 
                        (1.0 + 134.0 / 81.0 * delta1)));

         double delta0 = temp / (a0 * a0);

         m_rmMeanMotionRec    = rpmin / (1.0 + delta0);
         m_aeAxisSemiMajorRec = a0 / (1.0 - delta0);
         m_aeAxisSemiMinorRec = m_aeAxisSemiMajorRec * Math.Sqrt(1.0 - (e * e));
         m_kmPerigeeRec       = Globals.Xkmper * (m_aeAxisSemiMajorRec * (1.0 - e) - Globals.Ae);
         m_kmApogeeRec        = Globals.Xkmper * (m_aeAxisSemiMajorRec * (1.0 + e) - Globals.Ae);

         if ((Period.Ticks * 1.66666666666667E-09) >= 225.0)
         {
            // SDP4 - period >= 225 minutes.
            NoradModel = new NoradSDP4(this);
         }
         else
         {
            // SGP4 - period < 225 minutes
            NoradModel = new NoradSGP4(this);
         }
      }