src/FDM/JSBSim/models/FGMassBalance.cpp

   1 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2
   3  Module:       FGMassBalance.cpp
   4  Author:       Jon S. Berndt
   5  Date started: 09/12/2000
   6  Purpose:      This module models weight and balance
   7
   8  ------------- Copyright (C) 2000  Jon S. Berndt (jon@jsbsim.org) --------------
   9
  10  This program is free software; you can redistribute it and/or modify it under
  11  the terms of the GNU Lesser General Public License as published by the Free Software
  12  Foundation; either version 2 of the License, or (at your option) any later
  13  version.
  14
  15  This program is distributed in the hope that it will be useful, but WITHOUT
  16  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  17  FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
  18  details.
  19
  20  You should have received a copy of the GNU Lesser General Public License along with
  21  this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  22  Place - Suite 330, Boston, MA  02111-1307, USA.
  23
  24  Further information about the GNU Lesser General Public License can also be found on
  25  the world wide web at http://www.gnu.org.
  26
  27 FUNCTIONAL DESCRIPTION
  28 --------------------------------------------------------------------------------
  29
  30 This class models the change in weight and balance of the aircraft due to fuel
  31 burnoff, etc.
  32
  33 HISTORY
  34 --------------------------------------------------------------------------------
  35 09/12/2000  JSB  Created
  36
  37 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  38 INCLUDES
  39 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  40
  41 #include "FGMassBalance.h"
  42 #include "FGPropulsion.h"
  43 #include "propulsion/FGTank.h"
  44 #include "FGBuoyantForces.h"
  45 #include "input_output/FGPropertyManager.h"
  46 #include <iostream>
  47 #include <iomanip>
  48 #include <cstdlib>
  49
  50 using namespace std;
  51
  52 namespace JSBSim {
  53
  54 static const char *IdSrc = "$Id: FGMassBalance.cpp,v 1.31 2010/02/19 00:30:00 jberndt Exp $";
  55 static const char *IdHdr = ID_MASSBALANCE;
  56
  57 /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  58 CLASS IMPLEMENTATION
  59 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
  60
  61
  62 FGMassBalance::FGMassBalance(FGFDMExec* fdmex) : FGModel(fdmex)
  63 {
  64   Name = "FGMassBalance";
  65   Weight = EmptyWeight = Mass = 0.0;
  66
  67   vbaseXYZcg.InitMatrix(0.0);
  68   vXYZcg.InitMatrix(0.0);
  69   vLastXYZcg.InitMatrix(0.0);
  70   vDeltaXYZcg.InitMatrix(0.0);
  71   baseJ.InitMatrix();
  72   mJ.InitMatrix();
  73   mJinv.InitMatrix();
  74   pmJ.InitMatrix();
  75
  76   bind();
  77
  78   Debug(0);
  79 }
  80
  81 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  82
  83 FGMassBalance::~FGMassBalance()
  84 {
  85   for (unsigned int i=0; i<PointMasses.size(); i++) delete PointMasses[i];
  86   PointMasses.clear();
  87
  88   Debug(1);
  89 }
  90
  91 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  92
  93 bool FGMassBalance::InitModel(void)
  94 {
  95   if (!FGModel::InitModel()) return false;
  96
  97   vLastXYZcg.InitMatrix(0.0);
  98   vDeltaXYZcg.InitMatrix(0.0);
  99
 100   return true;
 101 }
 102
 103 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 104
 105 bool FGMassBalance::Load(Element* el)
 106 {
 107   Element *element;
 108   string element_name = "";
 109   double bixx, biyy, bizz, bixy, bixz, biyz;
 110
 111   FGModel::Load(el); // Perform base class Load.
 112
 113   bixx = biyy = bizz = bixy = bixz = biyz = 0.0;
 114   if (el->FindElement("ixx"))
 115     bixx = el->FindElementValueAsNumberConvertTo("ixx", "SLUG*FT2");
 116   if (el->FindElement("iyy"))
 117     biyy = el->FindElementValueAsNumberConvertTo("iyy", "SLUG*FT2");
 118   if (el->FindElement("izz"))
 119     bizz = el->FindElementValueAsNumberConvertTo("izz", "SLUG*FT2");
 120   if (el->FindElement("ixy"))
 121     bixy = el->FindElementValueAsNumberConvertTo("ixy", "SLUG*FT2");
 122   if (el->FindElement("ixz"))
 123     bixz = el->FindElementValueAsNumberConvertTo("ixz", "SLUG*FT2");
 124   if (el->FindElement("iyz"))
 125     biyz = el->FindElementValueAsNumberConvertTo("iyz", "SLUG*FT2");
 126   SetAircraftBaseInertias(FGMatrix33(  bixx,  -bixy,  bixz,
 127                                       -bixy,  biyy,  -biyz,
 128                                        bixz,  -biyz,  bizz ));
 129   if (el->FindElement("emptywt")) {
 130     EmptyWeight = el->FindElementValueAsNumberConvertTo("emptywt", "LBS");
 131   }
 132
 133   element = el->FindElement("location");
 134   while (element) {
 135     element_name = element->GetAttributeValue("name");
 136     if (element_name == "CG") vbaseXYZcg = element->FindElementTripletConvertTo("IN");
 137     element = el->FindNextElement("location");
 138   }
 139
 140 // Find all POINTMASS elements that descend from this METRICS branch of the
 141 // config file.
 142
 143   element = el->FindElement("pointmass");
 144   while (element) {
 145     AddPointMass(element);
 146     element = el->FindNextElement("pointmass");
 147   }
 148
 149   double ChildFDMWeight = 0.0;
 150   for (int fdm=0; fdm<FDMExec->GetFDMCount(); fdm++) {
 151     if (FDMExec->GetChildFDM(fdm)->mated) ChildFDMWeight += FDMExec->GetChildFDM(fdm)->exec->GetMassBalance()->GetWeight();
 152   }
 153
 154   Weight = EmptyWeight + Propulsion->GetTanksWeight() + GetTotalPointMassWeight()
 155     + BuoyantForces->GetGasMass()*slugtolb + ChildFDMWeight;
 156
 157   Mass = lbtoslug*Weight;
 158
 159   FGModel::PostLoad(el);
 160
 161   Debug(2);
 162   return true;
 163 }
 164
 165 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 166
 167 bool FGMassBalance::Run(void)
 168 {
 169   double denom, k1, k2, k3, k4, k5, k6;
 170   double Ixx, Iyy, Izz, Ixy, Ixz, Iyz;
 171
 172   if (FGModel::Run()) return true;
 173   if (FDMExec->Holding()) return false;
 174
 175   RunPreFunctions();
 176
 177   double ChildFDMWeight = 0.0;
 178   for (int fdm=0; fdm<FDMExec->GetFDMCount(); fdm++) {
 179     if (FDMExec->GetChildFDM(fdm)->mated) ChildFDMWeight += FDMExec->GetChildFDM(fdm)->exec->GetMassBalance()->GetWeight();
 180   }
 181
 182   Weight = EmptyWeight + Propulsion->GetTanksWeight() + GetTotalPointMassWeight()
 183     + BuoyantForces->GetGasMass()*slugtolb + ChildFDMWeight;
 184
 185   Mass = lbtoslug*Weight;
 186
 187 // Calculate new CG
 188
 189   vXYZcg = (Propulsion->GetTanksMoment() + EmptyWeight*vbaseXYZcg
 190             + GetPointMassMoment()
 191             + BuoyantForces->GetGasMassMoment()) / Weight;
 192
 193   // Track frame-by-frame delta CG, and move the EOM-tracked location
 194   // by this amount.
 195   if (vLastXYZcg.Magnitude() == 0.0) vLastXYZcg = vXYZcg;
 196   vDeltaXYZcg = vXYZcg - vLastXYZcg;
 197   vDeltaXYZcgBody = StructuralToBody(vLastXYZcg) - StructuralToBody(vXYZcg);
 198   vLastXYZcg = vXYZcg;
 199   Propagate->NudgeBodyLocation(vDeltaXYZcgBody);
 200
 201 // Calculate new total moments of inertia
 202
 203   // At first it is the base configuration inertia matrix ...
 204   mJ = baseJ;
 205   // ... with the additional term originating from the parallel axis theorem.
 206   mJ += GetPointmassInertia( lbtoslug * EmptyWeight, vbaseXYZcg );
 207   // Then add the contributions from the additional pointmasses.
 208   mJ += CalculatePMInertias();
 209   mJ += Propulsion->CalculateTankInertias();
 210   mJ += BuoyantForces->GetGasMassInertia();
 211
 212   Ixx = mJ(1,1);
 213   Iyy = mJ(2,2);
 214   Izz = mJ(3,3);
 215   Ixy = -mJ(1,2);
 216   Ixz = -mJ(1,3);
 217   Iyz = -mJ(2,3);
 218
 219 // Calculate inertia matrix inverse (ref. Stevens and Lewis, "Flight Control & Simulation")
 220
 221   k1 = (Iyy*Izz - Iyz*Iyz);
 222   k2 = (Iyz*Ixz + Ixy*Izz);
 223   k3 = (Ixy*Iyz + Iyy*Ixz);
 224
 225   denom = 1.0/(Ixx*k1 - Ixy*k2 - Ixz*k3 );
 226   k1 = k1*denom;
 227   k2 = k2*denom;
 228   k3 = k3*denom;
 229   k4 = (Izz*Ixx - Ixz*Ixz)*denom;
 230   k5 = (Ixy*Ixz + Iyz*Ixx)*denom;
 231   k6 = (Ixx*Iyy - Ixy*Ixy)*denom;
 232
 233   mJinv.InitMatrix( k1, k2, k3,
 234                     k2, k4, k5,
 235                     k3, k5, k6 );
 236
 237   RunPostFunctions();
 238
 239   Debug(0);
 240
 241   return false;
 242 }
 243
 244 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 245
 246 void FGMassBalance::AddPointMass(Element* el)
 247 {
 248   double radius=0, length=0;
 249   Element* loc_element = el->FindElement("location");
 250   string pointmass_name = el->GetAttributeValue("name");
 251   if (!loc_element) {
 252     cerr << "Pointmass " << pointmass_name << " has no location." << endl;
 253     exit(-1);
 254   }
 255
 256   double w = el->FindElementValueAsNumberConvertTo("weight", "LBS");
 257   FGColumnVector3 vXYZ = loc_element->FindElementTripletConvertTo("IN");
 258
 259   PointMass *pm = new PointMass(w, vXYZ);
 260   pm->SetName(pointmass_name);
 261
 262   Element* form_element = el->FindElement("form");
 263   if (form_element) {
 264     string shape = form_element->GetAttributeValue("shape");
 265     Element* radius_element = form_element->FindElement("radius");
 266     Element* length_element = form_element->FindElement("length");
 267     if (radius_element) radius = form_element->FindElementValueAsNumberConvertTo("radius", "FT");
 268     if (length_element) length = form_element->FindElementValueAsNumberConvertTo("length", "FT");
 269     if (shape == "tube") {
 270       pm->SetPointMassShapeType(PointMass::esTube);
 271       pm->SetRadius(radius);
 272       pm->SetLength(length);
 273       pm->CalculateShapeInertia();
 274     } else if (shape == "cylinder") {
 275       pm->SetPointMassShapeType(PointMass::esCylinder);
 276       pm->SetRadius(radius);
 277       pm->SetLength(length);
 278       pm->CalculateShapeInertia();
 279     } else if (shape == "sphere") {
 280       pm->SetPointMassShapeType(PointMass::esSphere);
 281       pm->SetRadius(radius);
 282       pm->CalculateShapeInertia();
 283     } else {
 284     }
 285   }
 286
 287   pm->bind(PropertyManager, PointMasses.size());
 288   PointMasses.push_back(pm);
 289 }
 290
 291 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 292
 293 double FGMassBalance::GetTotalPointMassWeight(void)
 294 {
 295   double PM_total_weight = 0.0;
 296
 297   for (unsigned int i=0; i<PointMasses.size(); i++) {
 298     PM_total_weight += PointMasses[i]->Weight;
 299   }
 300   return PM_total_weight;
 301 }
 302
 303 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 304
 305 FGColumnVector3& FGMassBalance::GetPointMassMoment(void)
 306 {
 307   PointMassCG.InitMatrix();
 308
 309   for (unsigned int i=0; i<PointMasses.size(); i++) {
 310     PointMassCG += PointMasses[i]->Weight*PointMasses[i]->Location;
 311   }
 312   return PointMassCG;
 313 }
 314
 315 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 316
 317 FGMatrix33& FGMassBalance::CalculatePMInertias(void)
 318 {
 319   unsigned int size;
 320
 321   size = PointMasses.size();
 322   if (size == 0) return pmJ;
 323
 324   pmJ = FGMatrix33();
 325
 326   for (unsigned int i=0; i<size; i++) {
 327     pmJ += GetPointmassInertia( lbtoslug * PointMasses[i]->Weight, PointMasses[i]->Location );
 328     pmJ += PointMasses[i]->GetPointMassInertia();
 329   }
 330
 331   return pmJ;
 332 }
 333
 334 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 335
 336 FGColumnVector3 FGMassBalance::StructuralToBody(const FGColumnVector3& r) const
 337 {
 338   // Under the assumption that in the structural frame the:
 339   //
 340   // - X-axis is directed afterwards,
 341   // - Y-axis is directed towards the right,
 342   // - Z-axis is directed upwards,
 343   //
 344   // (as documented in http://jsbsim.sourceforge.net/JSBSimCoordinates.pdf)
 345   // we have to subtract first the center of gravity of the plane which
 346   // is also defined in the structural frame:
 347   //
 348   //   FGColumnVector3 cgOff = r - vXYZcg;
 349   //
 350   // Next, we do a change of units:
 351   //
 352   //   cgOff *= inchtoft;
 353   //
 354   // And then a 180 degree rotation is done about the Y axis so that the:
 355   //
 356   // - X-axis is directed forward,
 357   // - Y-axis is directed towards the right,
 358   // - Z-axis is directed downward.
 359   //
 360   // This is needed because the structural and body frames are 180 degrees apart.
 361
 362   return FGColumnVector3(inchtoft*(vXYZcg(1)-r(1)),
 363                          inchtoft*(r(2)-vXYZcg(2)),
 364                          inchtoft*(vXYZcg(3)-r(3)));
 365 }
 366
 367 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 368
 369 void FGMassBalance::bind(void)
 370 {
 371   typedef double (FGMassBalance::*PMF)(int) const;
 372   PropertyManager->Tie("inertia/mass-slugs", this,
 373                        &FGMassBalance::GetMass);
 374   PropertyManager->Tie("inertia/weight-lbs", this,
 375                        &FGMassBalance::GetWeight);
 376   PropertyManager->Tie("inertia/empty-weight-lbs", this,
 377                        &FGMassBalance::GetEmptyWeight);
 378   PropertyManager->Tie("inertia/cg-x-in", this,1,
 379                        (PMF)&FGMassBalance::GetXYZcg);
 380   PropertyManager->Tie("inertia/cg-y-in", this,2,
 381                        (PMF)&FGMassBalance::GetXYZcg);
 382   PropertyManager->Tie("inertia/cg-z-in", this,3,
 383                        (PMF)&FGMassBalance::GetXYZcg);
 384 }
 385
 386 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 387 //
 388 // This function binds properties for each pointmass object created.
 389 //
 390 void FGMassBalance::PointMass::bind(FGPropertyManager* PropertyManager, int num) {
 391   string tmp = CreateIndexedPropertyName("inertia/pointmass-weight-lbs", num);
 392   PropertyManager->Tie( tmp.c_str(), this, &PointMass::GetPointMassWeight,
 393                                        &PointMass::SetPointMassWeight);
 394
 395   tmp = CreateIndexedPropertyName("inertia/pointmass-location-X-inches", num);
 396   PropertyManager->Tie( tmp.c_str(), this, eX, &PointMass::GetPointMassLocation,
 397                                            &PointMass::SetPointMassLocation);
 398   tmp = CreateIndexedPropertyName("inertia/pointmass-location-Y-inches", num);
 399   PropertyManager->Tie( tmp.c_str(), this, eY, &PointMass::GetPointMassLocation,
 400                                            &PointMass::SetPointMassLocation);
 401   tmp = CreateIndexedPropertyName("inertia/pointmass-location-Z-inches", num);
 402   PropertyManager->Tie( tmp.c_str(), this, eZ, &PointMass::GetPointMassLocation,
 403                                            &PointMass::SetPointMassLocation);
 404 }
 405
 406 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 407
 408 void FGMassBalance::GetMassPropertiesReport(void) const
 409 {
 410   cout << endl << fgblue << highint
 411        << "  Mass Properties Report (English units: lbf, in, slug-ft^2)"
 412        << reset << endl;
 413   cout << "                                  " << underon << "    Weight    CG-X    CG-Y"
 414        << "    CG-Z         Ixx         Iyy         Izz" << underoff << endl;
 415   cout.precision(1);
 416   cout << highint << setw(34) << left << "    Base Vehicle " << normint
 417        << right << setw(10) << EmptyWeight << setw(8) << vbaseXYZcg(eX) << setw(8)
 418        << vbaseXYZcg(eY) << setw(8) << vbaseXYZcg(eZ) << setw(12) << baseJ(1,1)
 419        << setw(12) << baseJ(2,2) << setw(12) << baseJ(3,3) << endl;
 420
 421   for (unsigned int i=0;i<PointMasses.size();i++) {
 422     PointMass* pm = PointMasses[i];
 423     double pmweight = pm->GetPointMassWeight();
 424     cout << highint << left << setw(4) << i << setw(30) << pm->GetName() << normint
 425          << right << setw(10) << pmweight << setw(8) << pm->GetLocation()(eX)
 426          << setw(8) << pm->GetLocation()(eY) << setw(8) << pm->GetLocation()(eZ)
 427          << setw(12) << pm->GetPointMassMoI(1,1) << setw(12) << pm->GetPointMassMoI(2,2)
 428          << setw(12) << pm->GetPointMassMoI(3,3) << endl;
 429   }
 430
 431   for (unsigned int i=0;i<Propulsion->GetNumTanks() ;i++) {
 432     FGTank* tank = Propulsion->GetTank(i);
 433     string tankname="";
 434     if (tank->GetType() == FGTank::ttFUEL && tank->GetGrainType() != FGTank::gtUNKNOWN) {
 435       tankname = "Solid Fuel";
 436     } else if (tank->GetType() == FGTank::ttFUEL) {
 437       tankname = "Fuel";
 438     } else if (tank->GetType() == FGTank::ttOXIDIZER) {
 439       tankname = "Oxidizer";
 440     } else {
 441       tankname = "(Unknown tank type)";
 442     }
 443     cout << highint << left << setw(4) << i << setw(30) << tankname << normint
 444       << right << setw(10) << tank->GetContents() << setw(8) << tank->GetXYZ(eX)
 445          << setw(8) << tank->GetXYZ(eY) << setw(8) << tank->GetXYZ(eZ)
 446          << setw(12) << "*" << setw(12) << "*"
 447          << setw(12) << "*" << endl;
 448   }
 449
 450   cout << underon << setw(104) << " " << underoff << endl;
 451   cout << highint << left << setw(30) << "    Total: " << right << setw(14) << Weight
 452        << setw(8) << vXYZcg(eX)
 453        << setw(8) << vXYZcg(eY)
 454        << setw(8) << vXYZcg(eZ)
 455        << setw(12) << mJ(1,1)
 456        << setw(12) << mJ(2,2)
 457        << setw(12) << mJ(3,3)
 458        << normint << endl;
 459
 460   cout.setf(ios_base::fixed);
 461 }
 462
 463 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 464 //    The bitmasked value choices are as follows:
 465 //    unset: In this case (the default) JSBSim would only print
 466 //       out the normally expected messages, essentially echoing
 467 //       the config files as they are read. If the environment
 468 //       variable is not set, debug_lvl is set to 1 internally
 469 //    0: This requests JSBSim not to output any messages
 470 //       whatsoever.
 471 //    1: This value explicity requests the normal JSBSim
 472 //       startup messages
 473 //    2: This value asks for a message to be printed out when
 474 //       a class is instantiated
 475 //    4: When this value is set, a message is displayed when a
 476 //       FGModel object executes its Run() method
 477 //    8: When this value is set, various runtime state variables
 478 //       are printed out periodically
 479 //    16: When set various parameters are sanity checked and
 480 //       a message is printed out when they go out of bounds
 481
 482 void FGMassBalance::Debug(int from)
 483 {
 484   if (debug_lvl <= 0) return;
 485
 486   if (debug_lvl & 1) { // Standard console startup message output
 487     if (from == 2) { // Loading
 488       cout << endl << "  Mass and Balance:" << endl;
 489       cout << "    baseIxx: " << baseJ(1,1) << " slug-ft2" << endl;
 490       cout << "    baseIyy: " << baseJ(2,2) << " slug-ft2" << endl;
 491       cout << "    baseIzz: " << baseJ(3,3) << " slug-ft2" << endl;
 492       cout << "    baseIxy: " << baseJ(1,2) << " slug-ft2" << endl;
 493       cout << "    baseIxz: " << baseJ(1,3) << " slug-ft2" << endl;
 494       cout << "    baseIyz: " << baseJ(2,3) << " slug-ft2" << endl;
 495       cout << "    Empty Weight: " << EmptyWeight << " lbm" << endl;
 496       cout << "    CG (x, y, z): " << vbaseXYZcg << endl;
 497       // ToDo: Need to add point mass outputs here
 498       for (unsigned int i=0; i<PointMasses.size(); i++) {
 499         cout << "    Point Mass Object: " << PointMasses[i]->Weight << " lbs. at "
 500                    << "X, Y, Z (in.): " << PointMasses[i]->Location(eX) << "  "
 501                    << PointMasses[i]->Location(eY) << "  "
 502                    << PointMasses[i]->Location(eZ) << endl;
 503       }
 504     }
 505   }
 506   if (debug_lvl & 2 ) { // Instantiation/Destruction notification
 507     if (from == 0) cout << "Instantiated: FGMassBalance" << endl;
 508     if (from == 1) cout << "Destroyed:    FGMassBalance" << endl;
 509   }
 510   if (debug_lvl & 4 ) { // Run() method entry print for FGModel-derived objects
 511   }
 512   if (debug_lvl & 8 ) { // Runtime state variables
 513   }
 514   if (debug_lvl & 16) { // Sanity checking
 515     if (from == 2) {
 516       if (EmptyWeight <= 0.0 || EmptyWeight > 1e9)
 517         cout << "MassBalance::EmptyWeight out of bounds: " << EmptyWeight << endl;
 518       if (Weight <= 0.0 || Weight > 1e9)
 519         cout << "MassBalance::Weight out of bounds: " << Weight << endl;
 520       if (Mass <= 0.0 || Mass > 1e9)
 521         cout << "MassBalance::Mass out of bounds: " << Mass << endl;
 522     }
 523   }
 524   if (debug_lvl & 64) {
 525     if (from == 0) { // Constructor
 526       cout << IdSrc << endl;
 527       cout << IdHdr << endl;
 528     }
 529   }
 530 }
 531 }