src/FDM/JSBSim/models/FGAuxiliary.cpp

   1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2
   3  Module:       FGAuxiliary.cpp
   4  Author:       Tony Peden, Jon Berndt
   5  Date started: 01/26/99
   6  Purpose:      Calculates additional parameters needed by the visual system, etc.
   7  Called by:    FGSimExec
   8
   9  ------------- Copyright (C) 1999  Jon S. Berndt (jon@jsbsim.org) -------------
  10
  11  This program is free software; you can redistribute it and/or modify it under
  12  the terms of the GNU Lesser General Public License as published by the Free Software
  13  Foundation; either version 2 of the License, or (at your option) any later
  14  version.
  15
  16  This program is distributed in the hope that it will be useful, but WITHOUT
  17  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  18  FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
  19  details.
  20
  21  You should have received a copy of the GNU Lesser General Public License along with
  22  this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  23  Place - Suite 330, Boston, MA  02111-1307, USA.
  24
  25  Further information about the GNU Lesser General Public License can also be found on
  26  the world wide web at http://www.gnu.org.
  27
  28 FUNCTIONAL DESCRIPTION
  29 --------------------------------------------------------------------------------
  30 This class calculates various auxiliary parameters.
  31
  32 REFERENCES
  33   Anderson, John D. "Introduction to Flight", 3rd Edition, McGraw-Hill, 1989
  34                     pgs. 112-126
  35 HISTORY
  36 --------------------------------------------------------------------------------
  37 01/26/99   JSB   Created
  38
  39 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  40 INCLUDES
  41 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  42
  43 #include "FGAuxiliary.h"
  44 #include "FGAerodynamics.h"
  45 #include "FGPropagate.h"
  46 #include "FGAtmosphere.h"
  47 #include "FGFDMExec.h"
  48 #include "FGAircraft.h"
  49 #include "FGInertial.h"
  50 #include "FGExternalReactions.h"
  51 #include "FGBuoyantForces.h"
  52 #include "FGGroundReactions.h"
  53 #include "FGPropulsion.h"
  54 #include "FGMassBalance.h"
  55 #include "input_output/FGPropertyManager.h"
  56 #include <iostream>
  57
  58 using namespace std;
  59
  60 namespace JSBSim {
  61
  62 static const char *IdSrc = "$Id: FGAuxiliary.cpp,v 1.39 2010/07/09 12:06:11 jberndt Exp $";
  63 static const char *IdHdr = ID_AUXILIARY;
  64
  65 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  66 CLASS IMPLEMENTATION
  67 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  68
  69
  70 FGAuxiliary::FGAuxiliary(FGFDMExec* fdmex) : FGModel(fdmex)
  71 {
  72   Name = "FGAuxiliary";
  73   vcas = veas = pt = tat = 0;
  74   psl = rhosl = 1;
  75   qbar = 0;
  76   qbarUW = 0.0;
  77   qbarUV = 0.0;
  78   Re = 0.0;
  79   Mach = 0.0;
  80   alpha = beta = 0.0;
  81   adot = bdot = 0.0;
  82   gamma = Vt = Vground = 0.0;
  83   psigt = 0.0;
  84   day_of_year = 1;
  85   seconds_in_day = 0.0;
  86   hoverbmac = hoverbcg = 0.0;
  87   tatc = RankineToCelsius(tat);
  88
  89   vPilotAccel.InitMatrix();
  90   vPilotAccelN.InitMatrix();
  91   vToEyePt.InitMatrix();
  92   vAeroPQR.InitMatrix();
  93   vEulerRates.InitMatrix();
  94
  95   bind();
  96
  97   Debug(0);
  98 }
  99
 100 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 101
 102 bool FGAuxiliary::InitModel(void)
 103 {
 104   if (!FGModel::InitModel()) return false;
 105
 106   vcas = veas = pt = tat = 0;
 107   psl = rhosl = 1;
 108   qbar = 0;
 109   qbarUW = 0.0;
 110   qbarUV = 0.0;
 111   Mach = 0.0;
 112   alpha = beta = 0.0;
 113   adot = bdot = 0.0;
 114   gamma = Vt = Vground = 0.0;
 115   psigt = 0.0;
 116   day_of_year = 1;
 117   seconds_in_day = 0.0;
 118   hoverbmac = hoverbcg = 0.0;
 119
 120   vPilotAccel.InitMatrix();
 121   vPilotAccelN.InitMatrix();
 122   vToEyePt.InitMatrix();
 123   vAeroPQR.InitMatrix();
 124   vEulerRates.InitMatrix();
 125
 126   return true;
 127 }
 128
 129 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 130
 131 FGAuxiliary::~FGAuxiliary()
 132 {
 133   Debug(1);
 134 }
 135
 136 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 137
 138 bool FGAuxiliary::Run()
 139 {
 140   double A,B,D;
 141
 142   if (FGModel::Run()) return true; // return true if error returned from base class
 143   if (FDMExec->Holding()) return false;
 144
 145   RunPreFunctions();
 146
 147   const FGColumnVector3& vPQR = Propagate->GetPQR();
 148   const FGColumnVector3& vUVW = Propagate->GetUVW();
 149   const FGColumnVector3& vUVWdot = Propagate->GetUVWdot();
 150   const FGColumnVector3& vVel = Propagate->GetVel();
 151
 152   p = Atmosphere->GetPressure();
 153   rhosl = Atmosphere->GetDensitySL();
 154   psl = Atmosphere->GetPressureSL();
 155   sat = Atmosphere->GetTemperature();
 156
 157 // Rotation
 158
 159   double cTht = Propagate->GetCosEuler(eTht);
 160   double sTht = Propagate->GetSinEuler(eTht);
 161   double cPhi = Propagate->GetCosEuler(ePhi);
 162   double sPhi = Propagate->GetSinEuler(ePhi);
 163
 164   vEulerRates(eTht) = vPQR(eQ)*cPhi - vPQR(eR)*sPhi;
 165   if (cTht != 0.0) {
 166     vEulerRates(ePsi) = (vPQR(eQ)*sPhi + vPQR(eR)*cPhi)/cTht;
 167     vEulerRates(ePhi) = vPQR(eP) + vEulerRates(ePsi)*sTht;
 168   }
 169
 170 // 12/16/2005, JSB: For ground handling purposes, at this time, let's ramp
 171 // in the effects of wind from 10 fps to 30 fps when there is weight on the
 172 // landing gear wheels.
 173
 174   if (GroundReactions->GetWOW() && vUVW(eU) < 10) {
 175     vAeroPQR = vPQR;
 176     vAeroUVW = vUVW;
 177   } else if (GroundReactions->GetWOW() && vUVW(eU) < 30) {
 178     double factor = (vUVW(eU) - 10.0)/20.0;
 179     vAeroPQR = vPQR - factor*Atmosphere->GetTurbPQR();
 180     vAeroUVW = vUVW - factor*Propagate->GetTl2b()*Atmosphere->GetTotalWindNED();
 181   } else {
 182     FGColumnVector3 wind = Propagate->GetTl2b()*Atmosphere->GetTotalWindNED();
 183     vAeroPQR = vPQR - Atmosphere->GetTurbPQR();
 184     vAeroUVW = vUVW - wind;
 185   }
 186
 187   Vt = vAeroUVW.Magnitude();
 188   if ( Vt > 0.05) {
 189     if (vAeroUVW(eW) != 0.0)
 190       alpha = vAeroUVW(eU)*vAeroUVW(eU) > 0.0 ? atan2(vAeroUVW(eW), vAeroUVW(eU)) : 0.0;
 191     if (vAeroUVW(eV) != 0.0)
 192       beta = vAeroUVW(eU)*vAeroUVW(eU)+vAeroUVW(eW)*vAeroUVW(eW) > 0.0 ? atan2(vAeroUVW(eV),
 193              sqrt(vAeroUVW(eU)*vAeroUVW(eU) + vAeroUVW(eW)*vAeroUVW(eW))) : 0.0;
 194
 195     double mUW = (vAeroUVW(eU)*vAeroUVW(eU) + vAeroUVW(eW)*vAeroUVW(eW));
 196     double signU=1;
 197     if (vAeroUVW(eU) != 0.0)
 198       signU = vAeroUVW(eU)/fabs(vAeroUVW(eU));
 199
 200     if ( (mUW == 0.0) || (Vt == 0.0) ) {
 201       adot = 0.0;
 202       bdot = 0.0;
 203     } else {
 204       adot = (vAeroUVW(eU)*vUVWdot(eW) - vAeroUVW(eW)*vUVWdot(eU))/mUW;
 205       bdot = (signU*mUW*vUVWdot(eV) - vAeroUVW(eV)*(vAeroUVW(eU)*vUVWdot(eU)
 206               + vAeroUVW(eW)*vUVWdot(eW)))/(Vt*Vt*sqrt(mUW));
 207     }
 208   } else {
 209     alpha = beta = adot = bdot = 0;
 210   }
 211
 212   Re = Vt * Aircraft->Getcbar() / Atmosphere->GetKinematicViscosity();
 213
 214   qbar = 0.5*Atmosphere->GetDensity()*Vt*Vt;
 215   qbarUW = 0.5*Atmosphere->GetDensity()*(vAeroUVW(eU)*vAeroUVW(eU) + vAeroUVW(eW)*vAeroUVW(eW));
 216   qbarUV = 0.5*Atmosphere->GetDensity()*(vAeroUVW(eU)*vAeroUVW(eU) + vAeroUVW(eV)*vAeroUVW(eV));
 217   Mach = Vt / Atmosphere->GetSoundSpeed();
 218   MachU = vMachUVW(eU) = vAeroUVW(eU) / Atmosphere->GetSoundSpeed();
 219   vMachUVW(eV) = vAeroUVW(eV) / Atmosphere->GetSoundSpeed();
 220   vMachUVW(eW) = vAeroUVW(eW) / Atmosphere->GetSoundSpeed();
 221
 222 // Position
 223
 224   Vground = sqrt( vVel(eNorth)*vVel(eNorth) + vVel(eEast)*vVel(eEast) );
 225
 226   psigt = atan2(vVel(eEast), vVel(eNorth));
 227   if (psigt < 0.0) psigt += 2*M_PI;
 228   gamma = atan2(-vVel(eDown), Vground);
 229
 230   tat = sat*(1 + 0.2*Mach*Mach); // Total Temperature, isentropic flow
 231   tatc = RankineToCelsius(tat);
 232
 233   if (MachU < 1) {   // Calculate total pressure assuming isentropic flow
 234     pt = p*pow((1 + 0.2*MachU*MachU),3.5);
 235   } else {
 236     // Use Rayleigh pitot tube formula for normal shock in front of pitot tube
 237     B = 5.76*MachU*MachU/(5.6*MachU*MachU - 0.8);
 238     D = (2.8*MachU*MachU-0.4)*0.4167;
 239     pt = p*pow(B,3.5)*D;
 240   }
 241
 242   A = pow(((pt-p)/psl+1),0.28571);
 243   if (MachU > 0.0) {
 244     vcas = sqrt(7*psl/rhosl*(A-1));
 245     veas = sqrt(2*qbar/rhosl);
 246   } else {
 247     vcas = veas = 0.0;
 248   }
 249
 250   vPilotAccel.InitMatrix();
 251   if ( Vt > 1.0 ) {
 252      // Use the "+=" operator to avoid the creation of temporary objects.
 253      vAircraftAccel = Aerodynamics->GetForces();
 254      vAircraftAccel += Propulsion->GetForces();
 255      vAircraftAccel += GroundReactions->GetForces();
 256      vAircraftAccel += ExternalReactions->GetForces();
 257      vAircraftAccel += BuoyantForces->GetForces();
 258
 259      vAircraftAccel /= MassBalance->GetMass();
 260      // Nz is Acceleration in "g's", along normal axis (-Z body axis)
 261      Nz = -vAircraftAccel(eZ)/Inertial->gravity();
 262      vToEyePt = MassBalance->StructuralToBody(Aircraft->GetXYZep());
 263      vPilotAccel = vAircraftAccel + Propagate->GetPQRdot() * vToEyePt;
 264      vPilotAccel += vPQR * (vPQR * vToEyePt);
 265   } else {
 266      // The line below handles low velocity (and on-ground) cases, basically
 267      // representing the opposite of the force that the landing gear would
 268      // exert on the ground (which is just the total weight). This eliminates
 269      // any jitter that could be introduced by the landing gear. Theoretically,
 270      // this branch could be eliminated, with a penalty of having a short
 271      // transient at startup (lasting only a fraction of a second).
 272      vPilotAccel = Propagate->GetTl2b() * FGColumnVector3( 0.0, 0.0, -Inertial->gravity() );
 273      Nz = -vPilotAccel(eZ)/Inertial->gravity();
 274   }
 275
 276   vPilotAccelN = vPilotAccel/Inertial->gravity();
 277
 278   // VRP computation
 279   const FGLocation& vLocation = Propagate->GetLocation();
 280   FGColumnVector3& vrpStructural = Aircraft->GetXYZvrp();
 281   FGColumnVector3 vrpBody = MassBalance->StructuralToBody( vrpStructural );
 282   FGColumnVector3 vrpLocal = Propagate->GetTb2l() * vrpBody;
 283   vLocationVRP = vLocation.LocalToLocation( vrpLocal );
 284
 285   // Recompute some derived values now that we know the dependent parameters values ...
 286   hoverbcg = Propagate->GetDistanceAGL() / Aircraft->GetWingSpan();
 287
 288   FGColumnVector3 vMac = Propagate->GetTb2l()*MassBalance->StructuralToBody(Aircraft->GetXYZrp());
 289   hoverbmac = (Propagate->GetDistanceAGL() + vMac(3)) / Aircraft->GetWingSpan();
 290
 291   // when all model are executed,
 292   // please calculate the distance from the initial point
 293
 294   CalculateRelativePosition();
 295
 296   RunPostFunctions();
 297
 298   return false;
 299 }
 300
 301 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 302 //
 303 // A positive headwind is blowing with you, a negative headwind is blowing against you.
 304 // psi is the direction the wind is blowing *towards*.
 305
 306 double FGAuxiliary::GetHeadWind(void) const
 307 {
 308   double psiw,vw;
 309
 310   psiw = Atmosphere->GetWindPsi();
 311   vw = Atmosphere->GetTotalWindNED().Magnitude();
 312
 313   return vw*cos(psiw - Propagate->GetEuler(ePsi));
 314 }
 315
 316 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 317 //
 318 // A positive crosswind is blowing towards the right (from teh perspective of the
 319 // pilot). A negative crosswind is blowing towards the -Y direction (left).
 320 // psi is the direction the wind is blowing *towards*.
 321
 322 double FGAuxiliary::GetCrossWind(void) const
 323 {
 324   double psiw,vw;
 325
 326   psiw = Atmosphere->GetWindPsi();
 327   vw = Atmosphere->GetTotalWindNED().Magnitude();
 328
 329   return  vw*sin(psiw - Propagate->GetEuler(ePsi));
 330 }
 331
 332 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 333
 334 void FGAuxiliary::bind(void)
 335 {
 336   typedef double (FGAuxiliary::*PMF)(int) const;
 337   typedef double (FGAuxiliary::*PF)(void) const;
 338   PropertyManager->Tie("propulsion/tat-r", this, &FGAuxiliary::GetTotalTemperature);
 339   PropertyManager->Tie("propulsion/tat-c", this, &FGAuxiliary::GetTAT_C);
 340   PropertyManager->Tie("propulsion/pt-lbs_sqft", this, &FGAuxiliary::GetTotalPressure);
 341   PropertyManager->Tie("velocities/vc-fps", this, &FGAuxiliary::GetVcalibratedFPS);
 342   PropertyManager->Tie("velocities/vc-kts", this, &FGAuxiliary::GetVcalibratedKTS);
 343   PropertyManager->Tie("velocities/ve-fps", this, &FGAuxiliary::GetVequivalentFPS);
 344   PropertyManager->Tie("velocities/ve-kts", this, &FGAuxiliary::GetVequivalentKTS);
 345   PropertyManager->Tie("velocities/machU", this, &FGAuxiliary::GetMachU);
 346   PropertyManager->Tie("velocities/p-aero-rad_sec", this, eX, (PMF)&FGAuxiliary::GetAeroPQR);
 347   PropertyManager->Tie("velocities/q-aero-rad_sec", this, eY, (PMF)&FGAuxiliary::GetAeroPQR);
 348   PropertyManager->Tie("velocities/r-aero-rad_sec", this, eZ, (PMF)&FGAuxiliary::GetAeroPQR);
 349   PropertyManager->Tie("velocities/phidot-rad_sec", this, ePhi, (PMF)&FGAuxiliary::GetEulerRates);
 350   PropertyManager->Tie("velocities/thetadot-rad_sec", this, eTht, (PMF)&FGAuxiliary::GetEulerRates);
 351   PropertyManager->Tie("velocities/psidot-rad_sec", this, ePsi, (PMF)&FGAuxiliary::GetEulerRates);
 352   PropertyManager->Tie("velocities/u-aero-fps", this, eU, (PMF)&FGAuxiliary::GetAeroUVW);
 353   PropertyManager->Tie("velocities/v-aero-fps", this, eV, (PMF)&FGAuxiliary::GetAeroUVW);
 354   PropertyManager->Tie("velocities/w-aero-fps", this, eW, (PMF)&FGAuxiliary::GetAeroUVW);
 355   PropertyManager->Tie("velocities/vt-fps", this, &FGAuxiliary::GetVt, &FGAuxiliary::SetVt, true);
 356   PropertyManager->Tie("velocities/mach", this, &FGAuxiliary::GetMach, &FGAuxiliary::SetMach, true);
 357   PropertyManager->Tie("velocities/vg-fps", this, &FGAuxiliary::GetVground);
 358   PropertyManager->Tie("accelerations/a-pilot-x-ft_sec2", this, eX, (PMF)&FGAuxiliary::GetPilotAccel);
 359   PropertyManager->Tie("accelerations/a-pilot-y-ft_sec2", this, eY, (PMF)&FGAuxiliary::GetPilotAccel);
 360   PropertyManager->Tie("accelerations/a-pilot-z-ft_sec2", this, eZ, (PMF)&FGAuxiliary::GetPilotAccel);
 361   PropertyManager->Tie("accelerations/n-pilot-x-norm", this, eX, (PMF)&FGAuxiliary::GetNpilot);
 362   PropertyManager->Tie("accelerations/n-pilot-y-norm", this, eY, (PMF)&FGAuxiliary::GetNpilot);
 363   PropertyManager->Tie("accelerations/n-pilot-z-norm", this, eZ, (PMF)&FGAuxiliary::GetNpilot);
 364   PropertyManager->Tie("accelerations/Nz", this, &FGAuxiliary::GetNz);
 365   /* PropertyManager->Tie("atmosphere/headwind-fps", this, &FGAuxiliary::GetHeadWind, true);
 366   PropertyManager->Tie("atmosphere/crosswind-fps", this, &FGAuxiliary::GetCrossWind, true); */
 367   PropertyManager->Tie("aero/alpha-rad", this, (PF)&FGAuxiliary::Getalpha, &FGAuxiliary::Setalpha, true);
 368   PropertyManager->Tie("aero/beta-rad", this, (PF)&FGAuxiliary::Getbeta, &FGAuxiliary::Setbeta, true);
 369   PropertyManager->Tie("aero/mag-beta-rad", this, (PF)&FGAuxiliary::GetMagBeta);
 370   PropertyManager->Tie("aero/alpha-deg", this, inDegrees, (PMF)&FGAuxiliary::Getalpha);
 371   PropertyManager->Tie("aero/beta-deg", this, inDegrees, (PMF)&FGAuxiliary::Getbeta);
 372   PropertyManager->Tie("aero/mag-beta-deg", this, inDegrees, (PMF)&FGAuxiliary::GetMagBeta);
 373   PropertyManager->Tie("aero/Re", this, &FGAuxiliary::GetReynoldsNumber);
 374   PropertyManager->Tie("aero/qbar-psf", this, &FGAuxiliary::Getqbar, &FGAuxiliary::Setqbar, true);
 375   PropertyManager->Tie("aero/qbarUW-psf", this, &FGAuxiliary::GetqbarUW, &FGAuxiliary::SetqbarUW, true);
 376   PropertyManager->Tie("aero/qbarUV-psf", this, &FGAuxiliary::GetqbarUV, &FGAuxiliary::SetqbarUV, true);
 377   PropertyManager->Tie("aero/alphadot-rad_sec", this, (PF)&FGAuxiliary::Getadot, &FGAuxiliary::Setadot, true);
 378   PropertyManager->Tie("aero/betadot-rad_sec", this, (PF)&FGAuxiliary::Getbdot, &FGAuxiliary::Setbdot, true);
 379   PropertyManager->Tie("aero/alphadot-deg_sec", this, inDegrees, (PMF)&FGAuxiliary::Getadot);
 380   PropertyManager->Tie("aero/betadot-deg_sec", this, inDegrees, (PMF)&FGAuxiliary::Getbdot);
 381   PropertyManager->Tie("aero/h_b-cg-ft", this, &FGAuxiliary::GetHOverBCG);
 382   PropertyManager->Tie("aero/h_b-mac-ft", this, &FGAuxiliary::GetHOverBMAC);
 383   PropertyManager->Tie("flight-path/gamma-rad", this, &FGAuxiliary::GetGamma, &FGAuxiliary::SetGamma);
 384   PropertyManager->Tie("flight-path/psi-gt-rad", this, &FGAuxiliary::GetGroundTrack);
 385
 386   PropertyManager->Tie("position/distance-from-start-lon-mt", this, &FGAuxiliary::GetLongitudeRelativePosition);
 387   PropertyManager->Tie("position/distance-from-start-lat-mt", this, &FGAuxiliary::GetLatitudeRelativePosition);
 388   PropertyManager->Tie("position/distance-from-start-mag-mt", this, &FGAuxiliary::GetDistanceRelativePosition);
 389   PropertyManager->Tie("position/vrp-gc-latitude_deg", &vLocationVRP, &FGLocation::GetLatitudeDeg);
 390   PropertyManager->Tie("position/vrp-longitude_deg", &vLocationVRP, &FGLocation::GetLongitudeDeg);
 391   PropertyManager->Tie("position/vrp-radius-ft", &vLocationVRP, &FGLocation::GetRadius);
 392 }
 393
 394 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 395
 396 void FGAuxiliary::CalculateRelativePosition(void)
 397 {
 398   const double earth_radius_mt = Inertial->GetRefRadius()*fttom;
 399   lat_relative_position=(FDMExec->GetPropagate()->GetLatitude()  - FDMExec->GetIC()->GetLatitudeDegIC() *degtorad)*earth_radius_mt;
 400   lon_relative_position=(FDMExec->GetPropagate()->GetLongitude() - FDMExec->GetIC()->GetLongitudeDegIC()*degtorad)*earth_radius_mt;
 401   relative_position = sqrt(lat_relative_position*lat_relative_position + lon_relative_position*lon_relative_position);
 402 };
 403
 404 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 405
 406 double FGAuxiliary::BadUnits(void) const
 407 {
 408   cerr << "Bad units" << endl; return 0.0;
 409 }
 410
 411 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 412 //    The bitmasked value choices are as follows:
 413 //    unset: In this case (the default) JSBSim would only print
 414 //       out the normally expected messages, essentially echoing
 415 //       the config files as they are read. If the environment
 416 //       variable is not set, debug_lvl is set to 1 internally
 417 //    0: This requests JSBSim not to output any messages
 418 //       whatsoever.
 419 //    1: This value explicity requests the normal JSBSim
 420 //       startup messages
 421 //    2: This value asks for a message to be printed out when
 422 //       a class is instantiated
 423 //    4: When this value is set, a message is displayed when a
 424 //       FGModel object executes its Run() method
 425 //    8: When this value is set, various runtime state variables
 426 //       are printed out periodically
 427 //    16: When set various parameters are sanity checked and
 428 //       a message is printed out when they go out of bounds
 429
 430 void FGAuxiliary::Debug(int from)
 431 {
 432   if (debug_lvl <= 0) return;
 433
 434   if (debug_lvl & 1) { // Standard console startup message output
 435     if (from == 0) { // Constructor
 436
 437     }
 438   }
 439   if (debug_lvl & 2 ) { // Instantiation/Destruction notification
 440     if (from == 0) cout << "Instantiated: FGAuxiliary" << endl;
 441     if (from == 1) cout << "Destroyed:    FGAuxiliary" << endl;
 442   }
 443   if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
 444   }
 445   if (debug_lvl & 8 ) { // Runtime state variables
 446   }
 447   if (debug_lvl & 16) { // Sanity checking
 448     if (Mach > 100 || Mach < 0.00)
 449       cout << "FGPropagate::Mach is out of bounds: " << Mach << endl;
 450     if (qbar > 1e6 || qbar < 0.00)
 451       cout << "FGPropagate::qbar is out of bounds: " << qbar << endl;
 452   }
 453   if (debug_lvl & 64) {
 454     if (from == 0) { // Constructor
 455       cout << IdSrc << endl;
 456       cout << IdHdr << endl;
 457     }
 458   }
 459 }
 460
 461 } // namespace JSBSim